TWI700306B - Foamed particle, foam molded body, method for manufacturing them and resin composite - Google Patents

Abstract

The present invention relates to a foamed particle of a thermoplastic aromatic polyester resin composition, wherein the thermoplastic aromatic polyester resin composition comprises a crystalline aromatic polyester resin and an amorphous aromatic polyester resin, and the foamed particles have the following properties in the DSC curve obtained when heated from 30℃ to 290℃ at a heating rate of 10℃/min: (1) the DSC curve has one glass transition temperature and a crystallization peak, (2) the heat of crystallization determined from the area of the crystallization peak is at least 20 mJ/mg, and (3) the half-crystallization time at 120℃ is 180 to 1000 seconds.

Description

Expanded particles, expanded molded body, manufacturing method thereof, and resin composite

The present invention relates to a foamed particle, a foamed molded product, a manufacturing method thereof, and a resin composite. In more detail, the present invention relates to expanded particles used to produce foamed molded articles with beautiful appearance and excellent heat resistance and mechanical strength, and foamed molded articles with beautiful appearance and excellent heat resistance and mechanical strength. , These manufacturing methods and resin composites. Since the foamed molded product of the present invention has excellent light weight, heat resistance, cushioning properties and mechanical strength, it can be suitably used in parts of transportation equipment such as automobiles, aircraft, railway vehicles, ships, and industrial equipment such as windmill blades. . Moreover, the resin composite formed by integrating the fiber-reinforced resin layer on the surface area of the foamed molded body has more excellent heat resistance and mechanical strength, and can be suitably used as parts of the above-mentioned transportation equipment, including components that constitute automobiles, Structural members including structural members of the main body of transportation equipment such as aircraft, railway vehicles, ships, etc., as well as parts of the above-mentioned industrial equipment, and structural members including structural members constituting the main body of industrial equipment such as windmill blades.

Thermoplastic aromatic polyester resins such as polyethylene terephthalate (PET) are expected to provide foamed molded products with excellent rigidity and dimensional stability. Therefore, for foamed molded products using this resin, There are reports in various literatures that present research results. For example, Patent Document 1 (Japanese Patent Laid-Open No. 2014-70153) describes a composition containing 100 parts by mass of an amorphous thermoplastic polyester resin and 10 to 900 parts by mass of a crystalline thermoplastic polyester resin as a thermoplastic polyester resin的foamed particles. Amorphous thermoplastic polyester resins include at least those containing 1,4-cyclohexanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol or spiroglycol A resin with a diol component and a glass transition temperature Tg of 100 to 130°C. The crystalline thermoplastic polyester resin includes resins with an inherent viscosity of 0.8 to 1.1. In Patent Document 1, it is possible to provide expanded particles made of a thermoplastic polyester resin capable of producing a foamed molded article having excellent foamability and excellent heat resistance, cushioning properties, and mechanical strength.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2014-70153 A

In Patent Document 1, two types of polyester resins are used. Since these two resin systems are completely incompatible, two Tgs can be observed in the resin composition blended with these resins. When the resin composition is to be extruded and foamed to produce expanded particles, it is not only difficult to extrude and foam the amorphous thermoplastic polyester resin itself, but also because of the amorphous thermoplastic polyester resin. It is different from the suitable foaming temperature of the crystalline thermoplastic polyester resin, so even if it is adjusted to any suitable foaming temperature, expanded particles with a sufficiently low open cell ratio (less than 15%) may not be obtained. In addition, when the foamed particles with a high open cell ratio are used to produce foamed molded articles, the secondary foaming power of the expanded particles is low, so foamed molded articles with poor surface properties may be obtained. There is still room for improvement in the appearance of the body.

In order to solve the above-mentioned problems, the inventors of the present invention have further sincerely studied the results and found that by making amorphous aromatic polyester resins containing crystalline aromatic polyester resins and having high compatibility with the crystalline aromatic polyester resins The resin composition of the aromatic polyester resin is foamed, and the glass transition temperature Tg can be obtained as one and the foamed particles with a low open cell rate that can be controlled to the desired crystallization rate. The foamed particles are formed in a mold Sufficient foamability can be exerted in the medium, and by using the expanded particles, a foamed molded article with good appearance can be obtained, and the present invention has been completed.

Thus, according to the present invention, there can be provided expanded particles which are expanded particles of a thermoplastic aromatic polyester resin composition, wherein the thermoplastic aromatic polyester resin composition contains a crystalline aromatic polyester resin composition. Resins and non-crystalline aromatic polyester resins, the aforementioned expanded particle system, when heated from 30°C to 290°C at a heating rate of 10°C/min, shows the following properties in the DSC curve: (1) The aforementioned The DSC curve shows a glass transition temperature and a crystallization peak; (2) the heat of crystallization calculated from the area of the aforementioned crystallization peak is 20mJ/mg or more; and (3) the half crystallization time at 120°C From 180 to 1000 seconds.

Furthermore, according to the present invention, it is possible to provide a foamed molded article obtained by foaming and molding the above-mentioned expanded particles in a mold.

Furthermore, according to the present invention, it is possible to provide a resin composite having the above-mentioned foamed molded body and a fiber-reinforced resin layer laminated on the surface of the foamed molded body and integrated.

In addition, according to the present invention, there can be provided a method for producing expanded particles, which is the method for producing the above-mentioned expanded particles, and the production method includes the following steps: combining a crystalline aromatic polyester resin and an amorphous aromatic poly The thermoplastic aromatic polyester resin composition of the ester resin is supplied to the extruder, and the supplied material supplied to the aforementioned extruder is extruded and foamed while being melted and kneaded in the presence of a foaming agent to obtain the extrusion A step of melt extrusion of the foam; and a step of cutting the aforementioned extruded foam to obtain expanded particles.

Moreover, according to the present invention, there can be provided a method of manufacturing a foamed molded body, which includes the following steps: a filling step of filling the above-mentioned foamed particles into a cavity of a mold; and making the above-mentioned foamed particles two The step of foaming and integrating the obtained secondary foamed particles by heat fusion to obtain a foamed molded body.

According to the production method of the present invention, it is possible to provide expanded particles made of a thermoplastic aromatic polyester resin that can give a foamed molded article with a good appearance.

In any of the following cases, it is possible to provide expanded particles made of a thermoplastic aromatic polyester resin that can give a foamed molded article with a better appearance.

(1) The expanded particles show an open cell rate of less than 15%.

(2) Containing crystalline aromatic polyester in a ratio of 65 to 99% by mass and 35 to 1% by mass relative to 100% by mass of the total of crystalline aromatic polyester resin and amorphous aromatic polyester resin Based resins and amorphous aromatic polyester resins.

(3) Amorphous aromatic polyester resin shows a glass transition temperature of 60 to 90°C.

(4) The amorphous aromatic polyester-based resin exhibits an inherent viscosity (IV value) of 0.6 to 1.1.

(5) The difference in the glass transition temperature of each of the amorphous aromatic polyester resin and the crystalline aromatic polyester resin shows 15°C or less.

(6) The crystalline aromatic polyester resin is selected from polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polytrimethylene terephthalate, poly One or more of propylene naphthalate, a copolymer of amorphous aromatic polyester resin-based terephthalic acid, 1,4-cyclohexanedimethanol and/or neopentyl glycol.

1‧‧‧Nozzle mold

1a‧‧‧Front face

2‧‧‧Rotation axis

3‧‧‧Drive components

4‧‧‧Cooling components

5‧‧‧Rotating Blade

11‧‧‧Export Department

41‧‧‧Cooling drum

41a‧‧‧Front

41b‧‧‧ Zhoubi Department

41c‧‧‧Supply Port

41d‧‧‧Supply pipe

41e‧‧‧Exhaust outlet

41f‧‧‧Exhaust pipe

42‧‧‧Cooling fluid (cooling water)

A‧‧‧Imaginary circle

P‧‧‧Granular cut

X‧‧‧Flow direction of coolant

Figure 1 is a graph showing an example of a DSC curve.

Figure 2 is a graph showing an example of the DSC curve.

Fig. 3 is a schematic diagram showing an example of an apparatus for manufacturing expanded beads.

Fig. 4 is a schematic diagram showing an example of an apparatus for manufacturing expanded beads.

Fig. 5 is a schematic diagram showing an example of an apparatus for manufacturing expanded beads.

Hereinafter, the present invention will be explained in detail.

(Expanded particles)

(A) Physical properties

The expanded particles show the following properties in the DSC curve obtained when heated from 30°C to 290°C at a heating rate of 10°C/min: (1) The DSC curve shows a glass transition temperature and a crystallization peak, (2) The heat of crystallization obtained from the area of the crystallization peak is 20 mJ/mg or more, and (3) The half crystallization time at 120°C is 180 to 1000 seconds.

By exhibiting the aforementioned properties (1) to (3), the expanded particles can confirm that the crystalline aromatic polyester resin and the amorphous aromatic polyester resin are highly compatible. As a result, expanded particles with a low open cell ratio can be provided. In addition, such expanded particles can provide a molded foam having a beautiful appearance and excellent heat resistance and mechanical strength.

Regarding the crystalline components contained in the expanded particles, in terms of allowing the expanded particles to exhibit good secondary expandability, those that are not crystallized are advantageous. In addition, with regard to the crystalline component contained in the aforementioned expanded particles, it is advantageous that the expanded particles are not crystallized in terms of fusing the expanded particles.

Because of this situation, when the heat of crystallization obtained from the area of the crystallization peak is less than 20 mJ/mg, the foamed molded article may have less crystalline components and lower heat resistance. The heat of crystallization is preferably 22mJ/mg or more, preferably 25mJ/mg or more.

On the other hand, in terms of shortening the time of the crystallization promotion step (heat retention step) during the production of the foamed molded body and improving the productivity, the expanded particles should not excessively exist in the uncrystallized state of crystalline components. .

Because of this situation, the aforementioned heat of crystallization is preferably 32 mJ/mg or less, preferably 30 mJ/mg or less.

The heat of crystallization can be 20.0mJ/mg, 20.5mJ/mg, 21.0mJ/mg, 21.5mJ/mg, 22.0mJ/mg, 22.5mJ/mg, 23.0mJ/mg, 23.5mJ/mg, 24.0mJ/mg, 24.5mJ/mg, 25.0mJ/mg, 25.5mJ/mg, 26.0mJ/mg, 26.5mJ/mg, 27.0mJ/mg, 27.5mJ/mg, 28.0mJ/mg, 28.5mJ/mg, 29.0mJ/mg, 29.5mJ/mg, 30.0mJ/mg, 30.5mJ/mg, 31.0mJ/mg, 31.5mJ/mg, 32.0mJ/mg.

In addition, the half crystallization time of the expanded particles of the present invention at 120°C is 180 seconds or more and 1000 seconds or less.

When the half crystallization time at 120°C is less than 180 seconds, the crystallization speed of the expanded particles is fast, and the degree of crystallinity of the expanded particles increases before the expanded particles are fused with each other during the foaming and molding in the mold. For this reason, the fusion of the foamed molded product may decrease and the mechanical strength may decrease. When it is longer than 1000 seconds, in order to promote the crystallization of the foamed molded body and exhibit excellent heat resistance, the heat retention step time (heat retention time) during the production of the foamed molded body must be increased, so the productivity may deteriorate. . Because of this situation, the aforementioned semi-crystallization time is preferably 200 to 800 seconds, and more preferably 230 to 500 seconds.

The semi-crystallization time can be 180 seconds, 200 seconds, 220 seconds, 230 seconds, 240 seconds, 260 seconds, 280 seconds, 300 seconds, 320 seconds, 340 seconds, 360 seconds, 380 seconds, 400 seconds, 420 seconds, 440 seconds , 460 seconds, 480 seconds, 500 seconds, 525 seconds, 550 seconds, 600 seconds, 650 seconds, 700 seconds, 750 seconds, 800 seconds, 850 seconds, 900 seconds, 950 seconds, 1000 seconds.

In addition, the expanded particles of the present invention preferably exhibit an open cell ratio of less than 15%. When the open cell ratio is 15% or more, sufficient foamability cannot be exhibited during in-mold molding. As a result, the mechanical strength of the obtained foamed molded article may be reduced, or it may be difficult to obtain a foamed molded article with good appearance. situation. The continuous bubble rate is preferably 13% or less, and more preferably 10% or less. The lower limit of the continuous bubble rate is 0%.

Expanded particles can use 14.99%, 14.9%, 14.5%, 14.0%, 13.5%, 13.0%, 12.5%, 12.0%, 11.5%, 11.0%, 10.5%, 10.0%, 9.5%, 9.0%, 8.5%, 8.0%, 7.5%, 7.0%, 6.5%, 6.0%, 5.5%, 5.0%, 4.5%, 4.0%, 3.5%, 3.0%, 2.5%, 2.0%, 1.5%, 1.0%, 0.5%, 0.1% , 0.01%, 0.001%, 0% continuous bubble rate.

The shape of the expanded particles is not particularly limited. For example, a spherical shape, a cylindrical shape, etc. are mentioned. Among them, it is preferable to have a spherical shape as close as possible. That is, the ratio of the short diameter to the long diameter of the expanded particles is preferably as close to 1 as possible.

The expanded particles preferably have an average particle diameter of 1 to 20 mm. The average particle size can be measured by classification using a sieve with a predetermined sieve opening.

The expanded particles can be 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm, 10.0mm, 10.5mm, 11.0mm, 11.5mm, 12.0mm, 12.5mm, 13.0mm, 13.5mm, 14.0mm, 14.5mm, 15.0mm, 15.5mm, 16.0mm, 16.5mm , 17.0mm, 17.5mm, 18.0mm, 18.5mm, 19.0mm, 19.5mm, 20.0mm average particle size.

The bulk density of the expanded particles is preferably 0.05 to 0.7 g/cm ³ . When the bulk density is less than 0.05 g/cm ³ , the continuous cell ratio of the expanded particles may increase, and the necessary foaming force may not be provided to the expanded particles during the expansion of the foam molding in the mold. When it is more than 0.7 g/cm ³ , the bubbles of the obtained expanded particles may become non-uniform, and the expandability of the expanded particles may become insufficient during foam molding in the mold. The bulk density is preferably 0.07 to 0.6 g/cm ^{3 and particularly} preferably 0.08 to 0.5 g/cm ³ .

The bulk density of the expanded particles can be 0.05g/cm ³ , 0.07g/cm ³ , 0.08g/cm ³ , 0.10g/cm ³ , 0.15g/cm ³ , 0.20g/cm ³ , 0.25g/cm ³ , 0.30g/cm ³ , 0.35g/cm ³ , 0.40g/cm ³ , 0.45g/cm ³ , 0.50g/cm ³ , 0.55g/cm ³ , 0.60g/cm ³ , 0.65g/cm ³ , 0.70g /cm ³ .

(B) Thermoplastic aromatic polyester resin composition

The expanded particles are composed of a thermoplastic aromatic polyester-based resin composition (hereinafter also simply referred to as a resin composition). The resin composition system contains a crystalline aromatic polyester resin and an amorphous aromatic polyester resin. The content of the two types of polyester resins in the resin composition can be 80% by mass or more, 90% by mass or more, or 100% by mass.

The content of the two polyester resins in the resin composition can be 80% by mass, 81.0% by mass, 82.5% by mass, 85% by mass, 87.5% by mass, 90.0% by mass, 92.5% by mass, 95.0% by mass, 97.5 mass%, 99.0 mass%, 99.9 mass%, 100 mass%.

In this specification, whether the polyester resin is crystalline or amorphous is judged according to the following points. First, a sample of polyester resin is heated and melted from 30°C at a heating rate of 10°C/min in accordance with JIS K7121: 1987 and 2012 "Method for Measuring the Transition Temperature of Plastics" using a differential scanning calorimetry (DSC). Up to 290°C and keep at 290°C for 10 minutes. After keeping, the sample was taken out of the heating furnace and left to cool to 30°C in an air environment at 25°C. Subsequently, the sample was heated and melted from 30°C to 290°C at a temperature increase rate of 10°C/min. In the second heating step, the thing that did not show the melting peak was judged to be amorphous, and the thing that showed the melting spike was judged to be crystalline.

(B-1) Crystalline aromatic polyester resin

The crystalline aromatic polyester-based resin includes polyester obtained by subjecting an aromatic dicarboxylic acid and a diol to an esterification reaction. Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfonic acid, and diphenoxy dicarboxylic acid. Acid etc. The aromatic dicarboxylic acid is preferably terephthalic acid and isophthalic acid. The aromatic dicarboxylic acid may be used alone or in combination of two or more kinds.

Examples of diols include aliphatic diols and alicyclic diols. Examples of the aliphatic glycol include ethylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, and diethylene glycol. Aliphatic diols are preferably ethylene glycol and diethylene glycol. Examples of the alicyclic diol include cyclohexane dimethanol. The diol may be used alone or in combination of two or more kinds.

Specific crystalline aromatic polyester resins include, for example, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polytrimethylene terephthalate, and poly(ethylene terephthalate). Propylene naphthalate, etc. The crystalline aromatic polyester resin may be used alone or in combination of two or more kinds. The crystalline aromatic polyester resin is preferably polyethylene terephthalate.

The crystalline aromatic polyester resin can be synthesized using a well-known method.

The crystalline aromatic polyester resin system preferably has an inherent viscosity (IV value) of 0.6 to 1.1. When the IV value is less than 0.6, foam breakage occurs during the production of the expanded particles, the continuous cell ratio of the obtained expanded particles may increase, and the secondary expandability of the expanded particles may decrease. When the IV value is greater than 1.1, the load during extrusion and foaming becomes too large and the productivity of the expanded particles may decrease, or the expansion ratio of the obtained expanded particles may decrease. As a result, the light weight or cushioning properties of the foamed molded article obtained using the expanded particles may be reduced. The IV value is preferably 0.65 to 1.05, more preferably 0.7 to 1.

The IV value of the crystalline aromatic polyester resin can be 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.88, 0.90, 0.95, 1.00, 1.05, and 1.10.

The crystalline aromatic polyester resin system preferably has a melting point (Tm) of 220 to 270°C. When the melting point is less than 220°C, because the reactivity of the thermoplastic aromatic polyester resin composition with the crosslinking agent is reduced, the resin composition is not sufficiently modified during the production of expanded particles and the extrusion foamability cannot be improved. Situation where extrusion foaming becomes difficult. In addition, even if expanded particles can be obtained, the continuous cell ratio of the expanded particles increases, the secondary expandability of the expanded particles decreases, and the lightweight or mechanical strength of the expanded molded article obtained using the expanded particles Reduced situation. When the temperature is higher than 280°C, it is necessary to extrude at a high temperature when producing expanded particles. In this case, the thermoplastic aromatic polyester resin composition is likely to undergo hydrolysis. When the expanded particles are manufactured under such conditions, the modification of the resin composition is insufficient, the extrusion foamability cannot be improved, and the extrusion foaming may become difficult. In addition, even if expanded particles can be obtained, the continuous cell ratio of the expanded particles increases, the secondary expandability of the expanded particles decreases, and the lightweight or mechanical strength of the expanded molded article obtained using the expanded particles Reduced situation. The melting point is preferably 230 to 265°C, more preferably 235 to 260°C.

The melting point can be 220.0℃, 222.5℃, 225.0℃, 227.5℃, 230.0℃, 232.5℃, 235.0℃, 237.5℃, 240.0℃, 242.5℃, 245.0℃, 247.0℃, 247.5℃, 250.0℃, 252.5℃, 255.0℃ , 257.5℃, 260.0℃, 262.5℃, 265.0℃, 267.5℃, 270.0℃.

The crystalline aromatic polyester resin system preferably has a glass transition temperature (Tg) of 60 to 90°C. When the glass transition temperature is less than 60°C, the mechanical strength of the foamed molded product in a high-temperature environment may decrease. When the temperature is higher than 90°C, the fusion property of the foamed molded article during foam molding in the mold may decrease, and the mechanical strength of the foamed molded article may decrease. The glass transition temperature is preferably 65 to 85°C, more preferably 70 to 80°C.

The glass transition temperature can be 60.0℃, 62.5℃, 65.0℃, 67.5℃, 70.0℃, 72.5℃, 75.0℃, 77.5℃, 78.0℃, 80.0℃, 82.5℃, 85.0℃, 87.5℃, 90.0℃.

(B-2) Amorphous aromatic polyester resin

Examples of the non-crystalline aromatic polyester resin include polyesters obtained by esterification reaction between aromatic dicarboxylic acid and diol. Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfonic acid, and diphenoxy dicarboxylic acid. Acid etc. The aromatic dicarboxylic acid is preferably terephthalic acid and isophthalic acid. The aromatic dicarboxylic acid may be used alone or in combination of two or more kinds.

Examples of diols include aliphatic diols and alicyclic diols. Aliphatic glycols include, for example, ethylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, diethylene glycol, propane glycol, 1,4-butane two Alcohol, polytetramethylene glycol, etc. Examples of the alicyclic diol include cyclohexanedimethanol, tetramethylcyclobutanediol, and spiroglycerin. The diols are preferably 1,4-cyclohexanedimethanol and neopentyl glycol. The diol may be used alone or in combination of two or more kinds.

The specific amorphous aromatic polyester resin system is preferably a copolymer of terephthalic acid, 1,4-cyclohexanedimethanol and/or neopentyl glycol. The ratio of 1,4-cyclohexanedimethanol and/or neopentyl glycol-derived units in the amorphous aromatic polyester resin is preferably 10 mol% or more, and 15 mol% % Or more is preferable, and 20 mol% or more is particularly preferable.

The ratio of units derived from 1,4-cyclohexanedimethanol and/or neopentyl glycol in the amorphous aromatic polyester resin can be 10.0 mol%, 12.5 mol%, and 15.0 mol%. Ear%, 17.5 mol%, 20.0 mol%, 22.5 mol%, 25.0 mol%, 30.0 mol%, 35.0 mol%, 40.0 mol%, 45.0 mol%, 50.0 mol%, 55.0 mol% Ear%, 60.0 mol%, 65.0 mol%, 70.0 mol%, 75.0 mol%, 80.0 mol%, 85.0 mol%, 90.0 mol%, 95.0 mol%, 99.0 mol%, 100 mol% ear%.

Amorphous aromatic polyester resin can be synthesized using a well-known method.

The amorphous aromatic polyester resin system preferably exhibits a glass transition temperature of 60 to 90°C. When the glass transition temperature is less than 60°C, the mechanical strength of the foamed molded product in a high-temperature environment may decrease. When the temperature is higher than 90°C, the compatibility of the amorphous thermoplastic polyester resin and the crystalline thermoplastic polyester resin is reduced, so that the open cell ratio of the obtained expanded particles becomes higher, and the expanded particles become secondary When the foamability is reduced and the lightness or mechanical strength of the foamed molded article obtained by using the expanded particles is reduced. In addition, during the in-mold foam molding, the fusion of the foamed molded article may decrease and the mechanical strength of the foamed molded article may decrease. The glass transition temperature is preferably 65 to 85°C, more preferably 70 to 80°C.

The glass transition temperature can be 60.0℃, 62.5℃, 65.0℃, 67.5℃, 70.0℃, 72.5℃, 75.0℃, 77.5℃, 78.0℃, 79.0℃, 80.0℃, 82.5℃, 85.0℃, 87.5℃, 90.0℃.

The difference in the glass transition temperature between the amorphous aromatic polyester resin and the crystalline aromatic polyester resin is preferably 15°C or less, and more preferably 10°C or less.

The difference between the glass transition temperature of the amorphous aromatic polyester resin and the crystalline aromatic polyester resin can be 15.0℃, 14.5℃, 14.0℃, 13.5℃, 13.0℃, 12.5℃, 12.0℃, 11.5℃、11.0℃、10.5℃、10.0℃、9.5℃、9.0℃、8.5℃、8.0℃、7.5℃、7.0℃、6.5℃、6.0℃、5.5℃、5.0℃、4.5℃、4.0℃、3.5℃ , 3.0℃, 2.5℃, 2.0℃, 1.5℃, 1.0℃, 0.5℃, 0.25℃, 0.1℃, 0℃.

The amorphous aromatic polyester-based resin system preferably has an IV value of 0.6 to 1.1. When the IV value is less than 0.6, foam breakage occurs during the production of expanded particles, and the continuous cell ratio of the obtained expanded particles may increase and the secondary expandability of the expanded particles may decrease. When the IV value is greater than 1.1, the load during extrusion and foaming becomes too large and the productivity of the expanded particles may decrease, or the expansion ratio of the obtained expanded particles may decrease. As a result, the lightweight or cushioning properties of the foamed molded article obtained using the expanded particles may be reduced. The IV value is preferably 0.65 to 1.05, more preferably 0.7 to 1.

The IV value can be 0.600, 0.625, 0.640, 0.650, 0.670, 0.675, 0.700, 0.725, 0.750, 0.775, 0.790, 0.800, 0.825, 0.850, 0.875, 0.900, 0.925, 0.950, 0.975, 1.000, 1.025, 1.050, 1.075, 1.100.

In addition, regarding the presence of components derived from monomers constituting the thermoplastic aromatic polyester resin, for example, the thermoplastic aromatic polyester resin can be dissolved in 1,1,1,3,3,3-hexafluoro-2- Propanol (HFIP-d ₂ , deuterated solvent) was measured using ¹ H-NMR.

The device and measurement conditions can be those described below, for example.

<device>

Bruker Biospin, AVANCE ^III -600 with Cryo Probe

<Measurement conditions>

Observation frequency = 600MHz ( ¹ H)

Determination solvent: HFIP-d ₂

Measuring temperature: 300K

Chemical shift standard = determination solvent (HFIP-d ₂ , ¹ H; 4.41 ppm)

(B-3) The content ratio of crystalline aromatic polyester resin to amorphous aromatic polyester resin

Relative to 100% by mass of the total of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin, the resin composition preferably contains crystals at a ratio of 65 to 99% by mass and 35 to 1% by mass. Aromatic aromatic polyester resin and non-crystalline aromatic polyester resin. When the ratio of the crystalline aromatic polyester-based resin is less than 65% by mass, the resin composition may not be sufficiently modified during the production of expanded particles, the extrusion foamability cannot be improved, and extrusion foaming may become difficult. In addition, even if expanded particles can be obtained, the continuous cell ratio of the expanded particles increases, the secondary expandability of the expanded particles decreases, and the lightweight or mechanical strength of the expanded molded article obtained using the expanded particles Reduced situation. When it is more than 99% by mass, the cushioning properties or impact resistance of the foamed molded article obtained by using the expanded particles may decrease. In addition, during foam molding in the mold, the fusion of the foamed molded article may decrease and the mechanical strength of the foamed molded article may decrease. The crystalline aromatic polyester resin and the amorphous aromatic polyester resin are more preferably contained in the ratio of 70 to 95% by mass and 30 to 5% by mass, and still more preferably 80 to 90% by mass and 20 It is contained up to 10% by mass.

Relative to the total 100% by mass of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin, the crystalline aromatic polyester resin and the amorphous aromatic polyester resin can be 65.0% by mass and 35.0% by mass, 67.5% by mass and 32.5% by mass, 70.0% by mass and 30.0% by mass, 72.5% by mass and 27.5% by mass, 75.0% by mass and 25.0% by mass, 77.5% by mass, and The ratio of 22.5% by mass, the ratio of 80.0% by mass and 20.0% by mass, the ratio of 82.5% by mass and 17.5% by mass, the ratio of 85.0% by mass and 15.0% by mass, the ratio of 87.5% by mass and 12.5% by mass, 90.0% by mass, and 10.0% by mass, 92.5% by mass and 7.5% by mass, 95.0% by mass and 5.0% by mass, 97.5% by mass and 2.5% by mass, 98.0% by mass and 2.0% by mass, 99.0% by mass, and 1.0% by mass ratio.

(B-4) Crosslinking agent

唑啉化合物、

化合物等。其中，以具有酸酐基之化合物為佳。又，交聯劑可單獨使用亦可併用2種以上。 The resin composition may contain a crosslinking agent. By containing the crosslinking agent, the extrusion foamability of the resin composition can be improved and expanded particles can be easily produced. A well-known thing can be used as a crosslinking agent. For example, compounds having acid anhydride groups, polyfunctional epoxy compounds,

Oxazoline compounds,

Compound etc. Among them, compounds having an acid anhydride group are preferred. Moreover, a crosslinking agent may be used individually or may use 2 or more types together.

The compound system which has an acid anhydride group is not specifically limited, For example, it may be any one of aromatic, alicyclic, and aliphatic. For example, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, diphenyl tetracarboxylic dianhydride, etc. are mentioned.

The content of the crosslinking agent is preferably 0.01 to 5 parts by mass relative to 100 parts by mass of the total of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin. When the content of the crosslinking agent is less than 0.01 parts by mass, the melt viscosity when the resin composition is melted is low, and foam may be broken during extrusion and foaming of the resin composition. If it is more than 5 parts by mass, the melt viscosity when the thermoplastic polyester resin is melted may become too high, and extrusion and foaming of the thermoplastic polyester resin may become difficult. Moreover, the production of expanded particles with a high expansion ratio may become difficult.

The content of the crosslinking agent is preferably 0.05 to 1% by mass, and more preferably 0.1 to 0.4% by mass.

The content of the crosslinking agent can be 0.01% by mass, 0.025% by mass, 0.05% by mass, 0.075% by mass, 0.10% by mass, 0.125% by mass, 0.15% by mass, 0.175% by mass, 0.20% by mass, 0.225% by mass, 0.24% by mass. , 0.25 mass%, 0.275 mass%, 0.30 mass%, 0.325 mass%, 0.35 mass%, 0.375 mass%, 0.40 mass%, 0.425 mass%, 0.45 mass%, 0.475 mass%, 0.50 mass%, 0.55 mass%, 0.60 Mass%, 0.65 mass%, 0.70 mass%, 0.75 mass%, 0.80 mass%, 0.85 mass%, 0.90 mass%, 0.95 mass%, 1.00 mass%, 1.25 mass%, 1.50 mass%, 2.00 mass%, 2.50 mass% , 3.00% by mass, 3.50% by mass, 4.00% by mass, 4.50% by mass, and 5.00% by mass.

(B-5) Other resin components

The resin composition may optionally contain resins other than the aforementioned thermoplastic aromatic polyester resin composition.

The resin composition can contain other resins other than the thermoplastic aromatic polyester resin composition, for example, polyolefin resins, polyamide resins, acrylic resins, saturated polyester resins, ABS resins, and polyolefin resins. Styrenic resin and polyphenylene oxide resin, etc.

The ratio of the other resin in the total resin components of the thermoplastic aromatic polyester resin composition is usually greater than 0% by mass and 20% by mass or less.

The aforementioned ratio of other resins is preferably 10% by mass or less, and more preferably 5% by mass or less.

(B-6) Additive

The expanded particles may contain additives in addition to the resin composition as necessary. Additives include bubble regulators, plasticizers, flame retardants, flame retardant additives, antistatic agents, spreaders, fillers, colorants, weathering agents, anti-aging agents, slip agents, anti-fogging agents, fragrances Wait.

Examples of the bubble regulator include inorganic bubble nucleating agents, sodium bicarbonate citric acid, higher fatty amides, higher fatty acid diamides, higher fatty acid salts, and the like. These bubble regulators may also be a combination of plural kinds.

Examples of inorganic bubble nucleating agents include talc, calcium silicate, synthetic or naturally produced silica, and the like.

The higher fatty amides include stearylamine, 12-hydroxystearylamine, and the like.

The higher fatty acid bis-stearyl amines include ethylene bis-stearyl amide, ethylene bis-stearyl amide, and methylene bis-stearyl amide.

The higher fatty acid salt includes calcium stearate.

The content of the cell regulator in the expanded particles is preferably 0.01 to 5 parts by mass relative to 100 parts by mass of the resin composition. When the content is less than 0.01 parts by mass, the bubbles of the expanded particles may become coarse and the appearance of the obtained foamed molded article may deteriorate. When it is more than 5 parts by mass, foam breakage occurs when the thermoplastic polyester resin material is extruded and foamed, and the open cell ratio of the expanded particles may increase. The content is preferably 0.05 to 3 parts by mass, and more preferably 0.1 to 2 parts by mass.

Relative to 100 parts by mass of the resin composition, the content of the air bubble regulator in the expanded particles can be 0.01 parts by mass, 0.025 parts by mass, 0.05 parts by mass, 0.075 parts by mass, 0.10 parts by mass, 0.15 parts by mass, 0.20 parts by mass, 0.25 Parts by mass, 0.30 parts by mass, 0.35 parts by mass, 0.40 parts by mass, 0.45 parts by mass, 0.50 parts by mass, 0.75 parts by mass, 1.00 parts by mass, 1.25 parts by mass, 1.50 parts by mass, 1.75 parts by mass, 1.80 parts by mass, 2.00 parts by mass , 2.25 parts by mass, 2.50 parts by mass, 2.75 parts by mass, 3.00 parts by mass, 3.50 parts by mass, 4.00 parts by mass, 4.50 parts by mass, and 5.00 parts by mass.

(Method of manufacturing expanded particles)

The manufacturing method of expanded particles includes the following steps: a thermoplastic aromatic polyester resin composition containing a crystalline aromatic polyester resin and an amorphous aromatic polyester resin is supplied to an extruder, and the The supply supplied to the aforementioned extruder is extruded and foamed while being melt-kneaded in the presence of a foaming agent to obtain an extruded foam; and the aforementioned extruded foam is cut to produce The cutting step to obtain expanded particles.

(A) Melt extrusion step

First, an example of the manufacturing apparatus used for the manufacture of the extruded foam will be described using FIGS. 3 to 5. In Figure 3, a nozzle die 1 is installed at the front end of the extruder. The nozzle mold 1 is preferably capable of extruding and foaming the resin composition to form uniform and fine bubbles. Furthermore, as shown in Fig. 4, on the front end surface 1a of the nozzle mold 1, a plurality of nozzle outlet portions 11 are formed on the same virtual circle A at regular intervals. In addition, regarding the nozzle mold installed at the tip of the extruder, there is no particular limitation as long as the resin composition does not foam in the nozzle.

The number of nozzles of the nozzle mold 1 is preferably 2 to 80. When the number of nozzles is one, the production efficiency of expanded beads may decrease. When the number is greater than 80, the extruded foams extruded and foamed from adjacent nozzles may contact each other and stick together. Furthermore, there may be cases where expanded particles obtained by cutting the extruded foam are stuck together. The number of nozzles is preferably from 5 to 60, and particularly preferably from 8 to 50.

The diameter of the nozzle outlet 11 of the nozzle mold 1 is preferably 0.2 to 2 mm. When the diameter is less than 0.2mm, the extrusion pressure may become too high and the extrusion foaming may become difficult. When it is larger than 2 mm, the diameter of the expanded particles may increase and the fillability of the mold may decrease. The diameter is preferably 0.3 to 1.6 mm, particularly 0.4 to 1.2 mm.

The length of the land portion of the nozzle mold 1 is preferably 4 to 30 times the diameter of the outlet portion 11 of the nozzle of the nozzle mold 1. When the length is less than 4 times, fracture may occur and stable extrusion and foaming may not be possible. When it is more than 30 times, it may not be possible to extrude and foam because of the excessive pressure applied to the nozzle mold. The length is preferably 5 to 20 times.

In the front end surface 1a surrounded by the nozzle outlet 11, a rotating shaft 2 is arranged in a state protruding forward, and the rotating shaft 2 is the front part 41a of the cooling drum 41 constituting the cooling member 4 described later It penetrates and is connected to a driving member 3 such as a motor.

Furthermore, one or more rotating blades 5 are integrally provided on the outer peripheral surface of the rear end of the rotating shaft 2, and all the rotating blades 5 are in a state of constantly contacting the front end surface 1a when rotating. In addition, when a plurality of rotating blades 5 are integrally provided on the rotating shaft 2, the plurality of rotating blades 5 are arranged in the circumferential direction of the rotating shaft 2 at regular intervals. Furthermore, in Fig. 4, as an example, a case where four rotating blades 5 are integrally provided on the outer peripheral surface of the rotating shaft 2 is shown.

Rotating by the rotating shaft 2, the rotating blade 5 moves on the imaginary circle A where the nozzle outlet 11 is formed while constantly contacting the front end surface 1a, and can be sequentially squeezed from the nozzle outlet 11 The extruded foam is constructed in a way that is sequentially and continuously cut.

In addition, a cooling member 4 is arranged so as to surround at least the tip portion of the nozzle mold 1 and the rotating shaft 2. The cooling member 4 is provided with a bottomed cylindrical cooling drum 41 having a front circular front portion 41a having a diameter larger than that of the nozzle mold 1, and extending rearward from the outer periphery of the front portion 41a The cylindrical peripheral wall 41b.

In addition, a portion of the peripheral wall portion 41b corresponding to the outer side of the nozzle mold 1 is formed with a supply port 41c for supplying the cooling liquid 42 in a state of penetrating between the inner and outer peripheral surfaces. The outer opening of the supply port 41 c is connected to a supply pipe 41 d for supplying the cooling liquid 42 into the cooling drum 41.

The cooling liquid 42 is configured to be able to pass through the supply pipe 41d and be supplied obliquely forward along the inner peripheral surface of the peripheral wall portion 41b of the cooling drum 41. The cooling liquid 42 travels forward along the inner peripheral surface of the peripheral wall portion 41b in a spiral shape by the centrifugal force accompanying the flow velocity when it is supplied from the supply pipe 41d to the inner peripheral surface of the peripheral wall portion 41b. Furthermore, the coolant 42 is gradually spreading in a direction orthogonal to the traveling direction while traveling along the inner peripheral surface of the peripheral wall portion 41b. As a result, the inner peripheral surface of the peripheral wall portion 41b ahead of the supply port 41c is It is configured to be in a state where the entire surface is covered by the coolant 42.

In addition, the cooling liquid 42 is not particularly limited as long as it can cool the granular cut material. For example, water, alcohols, etc. can be mentioned, and water is preferred when considering the treatment after use.

A discharge port 41e is formed on the lower surface of the front end of the peripheral wall portion 41b so as to penetrate between the inner and outer peripheral surfaces. The outer opening of the discharge port 41e is connected to the discharge pipe 41f. It is configured to be able to continuously discharge the granular cut material and the cooling liquid 42 through the discharge port 41e.

As far as the extruder is concerned, it is not particularly limited as long as it is a widely used extruder. For example, a single-axis extruder, a two-axis extruder, and a plurality of extruders are connected. The tandem extruder.

The foaming agent can use what has been widely used in the past. Examples of foaming agents include chemical foaming agents such as azodimethamide, dinitrosopentamethylenetetramine, hydrazine dimethylamide, and sodium bicarbonate; propane, n-butane, isobutane , Saturated aliphatic hydrocarbons such as n-pentane, isopentane, hexane, ethers such as dimethyl ether, methyl chloride, 1,1,1,2-tetrafluoroethane, 1,1-difluoro Ethane, monofluorodifluoromethane and other chlorofluorocarbons, carbon dioxide, nitrogen and other physical blowing agents, etc., preferably dimethyl ether, propane, n-butane, isobutane, carbon dioxide, and propane, n-butane, Isobutane is preferred, and n-butane and isobutane are particularly preferred. Moreover, a foaming agent may be used individually or may use 2 or more types together.

The amount of foaming agent supplied to the extruder is preferably 0.1 to 5 parts by mass relative to 100 parts by mass of the thermoplastic polyester resin. When the amount of blowing agent is less than 0.1 part by mass, the expanded particles may not be expanded to a desired expansion ratio. When the amount of blowing agent is more than 5 parts by mass, because the blowing agent acts as a plasticizer, the viscoelasticity of the resin composition in the molten state is excessively reduced, and the foamability is reduced, and good foamed particles cannot be obtained. situation. The amount of foaming agent is preferably 0.2 to 4 parts by mass, particularly preferably 0.3 to 3 parts by mass.

The air bubble regulator can also be supplied to the extruder.

(B) Cutting step

The extruded foam formed by extruding and foaming from the nozzle die 1 is followed by a cutting step. The cutting of the extruded foam is performed by rotating the rotating shaft 2 to rotate the rotating blade 5 arranged on the front end surface 1a. The number of revolutions of the rotating blade 5 is preferably 2000 to 10000 rpm. When the number of revolutions is less than 2000 rpm, the resin foam cannot be reliably cut by the rotating blade 5, and the expanded particles stick to each other, or the shape of the expanded particles may become uneven. When the number of revolutions exceeds 10,000 rpm, the following two problems are likely to occur. The first problem is that the cutting stress obtained by rotating the blade becomes larger, and when the expanded particles are scattered from the outlet of the nozzle toward the cooling member, the initial velocity of the expanded particles becomes faster. As a result, the time until the expanded particles collide with the cooling member after being cut is shortened, the expansion of the expanded particles is insufficient, and the expansion ratio may become low. The second problem is that the wear of the rotating blade and the rotating shaft becomes larger and the life of the rotating blade and the rotating shaft becomes shorter. It is better to rotate the blade with a certain number of revolutions. The number of revolutions is preferably from 2000 to 9000 rpm, and particularly preferably from 2000 to 8000 rpm.

All the rotating blades 5 are rotated while constantly contacting the front end surface 1a. The extruded foaming system formed by extruding and foaming from the nozzle die 1 is formed between the rotating blade 5 and the edge of the nozzle outlet 11 The shear stress generated is cut at regular intervals in the atmosphere and becomes a granular cut material. At this time, the water can be sprayed on the extruded foam in a range where the extruded foam is not excessively cooled.

In the nozzle of the nozzle mold 1, the resin composition is not foamed. In addition, the resin composition has not been foamed immediately after being discharged from the outlet portion 11 of the nozzle, and it starts to foam after a short time has passed after being discharged. Therefore, the extruded foaming system consists of the unfoamed part just after being ejected from the outlet 11 of the nozzle, and the foaming part in the foaming process that is extruded before the unfoamed part after the unfoamed part. Constituted.

During the period after the outlet portion 11 of the nozzle is discharged to the start of foaming, the unfoamed portion maintains its state. The time during which the unfoamed portion is maintained can be adjusted by the resin pressure at the outlet portion 11 of the nozzle, the amount of foaming, and the like. When the resin pressure at the outlet 11 of the nozzle is high, after the resin composition is extruded from the nozzle die 1, it does not immediately foam but maintains an unfoamed state. The adjustment of the resin pressure at the outlet 11 of the nozzle can be adjusted by the nozzle diameter, the extrusion amount, the melt viscosity and melt tension of the resin composition. By adjusting the amount of foaming agent to an appropriate amount, it is possible to prevent the resin composition from foaming inside the mold and to reliably form an unfoamed portion.

Since all the rotating blades 5 cut the extruded foam while constantly contacting the front end surface 1a, the extruded foaming system is cut at the unfoamed part just after being discharged from the outlet 11 of the nozzle. Then, granular cut products (expanded particles) are produced.

The granular cut material obtained as described above is cooled by the cutting stress obtained by the rotating blade 5 while being scattered toward the cooling drum 41 and immediately colliding with the inner peripheral surface of the covering peripheral wall portion 41b.液42. The granular cut material continues to foam until it collides with the cooling liquid 42, and the granular cut material grows into a roughly spherical shape by foaming. Therefore, the obtained expanded particles are roughly spherical. When the expanded particles are filled in the mold and the in-mold foaming is performed, the expanded particle system has excellent filling properties in the mold, and the expanded particles can be uniformly filled in the mold and a homogeneous expanded molded product can be obtained.

The entire inner peripheral surface of the peripheral wall portion 41b is covered with the coolant 42. This cooling liquid 42 is supplied obliquely forward along the inner peripheral surface of the peripheral wall portion 41b through the supply pipe 41d. The centrifugal force accompanied by the flow velocity when supplied from the supply pipe 41d to the inner peripheral surface of the peripheral wall portion 41b, And along the inner peripheral surface of the peripheral wall portion 41b, it travels forward in a spiral manner. The cooling liquid 42 gradually spreads in a direction orthogonal to the traveling direction while traveling along the inner peripheral surface of the peripheral wall portion 41b. As a result, the inner peripheral surface of the peripheral wall portion 41b ahead of the supply port 41c is in a state where the entire surface is covered by the coolant 42.

After cutting the extruded foam with the rotating blade 5, the granular cut material is immediately cooled with the cooling liquid 42, thereby preventing the expanded particles from being excessively foamed.

In addition, the granular cut product obtained by cutting the extruded foam using the rotating blade 5 is scattered toward the cooling liquid 42. As described above, the coolant 42 flowing along the inner peripheral surface of the peripheral wall portion 41b flows while rotating in a spiral shape. Therefore, it is preferable to make the granular cut material P obliquely cross the surface of the coolant 42 and from the upstream side to the downstream side of the flow of the coolant 42 to collide with the coolant 42 and enter the coolant 42 ( (Refer to Figure 5). In addition, in Fig. 5, the flow direction of the coolant is displayed as "X".

In this way, when the granular cut material enters the cooling liquid 42, the granular cut material is caused to enter the cooling liquid 42 from the direction following the flow of the cooling liquid 42, so the granular cut material is not exposed to the surface of the cooling liquid 42. It bounces, and the granular cut material system smoothly and surely enters the cooling liquid 42 and is cooled by the cooling liquid 42 to produce expanded particles.

Therefore, the expanded particles have a substantially spherical form without cooling unevenness and shrinkage, and exhibit excellent foamability during in-mold foam molding. In addition, the granular cut product is cooled immediately after the extruded foam is cut, but the crystalline aromatic polyester resin has a small increase in the degree of crystallinity and contains the amorphous aromatic polyester resin. Therefore, as a whole, the expanded particles have a low degree of crystallinity, so they have excellent heat fusibility and the resulting foamed molding system has excellent mechanical strength. In addition, the degree of crystallinity of the crystalline aromatic polyester resin is increased during the foam molding in the mold to improve heat resistance, and the resulting foam molding system has excellent heat resistance.

The temperature of the cooling liquid 42 is preferably 10 to 40°C. When the temperature is less than 10°C, the nozzle mold system located near the cooling drum 41 is excessively cooled, which may adversely affect the extrusion foaming of the resin composition. When the temperature is higher than 40°C, the cooling of the granular cut material may be insufficient.

The bulk density of the expanded particles can be adjusted by the resin pressure at the outlet 11 of the nozzle, the amount of foaming agent, or the like. The adjustment of the resin pressure at the outlet 11 of the nozzle can be adjusted by the nozzle diameter, the extrusion amount, and the melt viscosity of the resin composition.

The expanded particles are formed by cutting the extruded foam at the unexpanded part. On the surface of the part after cutting the extruded foam, the cross-section of the cell is not present at all or even if it exists, it is slightly. As a result, regarding the entire surface of the expanded particles, the cell cross-section system does not exist at all or only slightly exists. Therefore, the expanded particle system has no foaming gas detachment and has excellent foamability, has a low open cell ratio, and also has excellent surface thermal fusion properties.

(C) Other manufacturing methods

In the above, the case where the manufacturing apparatus shown in Figs. 3 to 5 is used as a method of manufacturing expanded particles is described, but it is not limited by the above manufacturing method. For example, the following manufacturing method may be used: (1) Resin composition It is supplied to the extruder and melt-kneaded in the presence of the foaming agent, and at the same time, the strand-like extruded hair is produced by extruding and foaming from the nozzle die installed at the tip of the extruder For foam, after cooling the strand-shaped extruded foam, it is cut into pellets using a pelletizer or the like to produce expanded particles (for the resin composition, in order to modify the resin contained, A crosslinking agent may be included as needed; the following (2) and (3) are also the same); (2) The resin composition is supplied to the extruder and melted and kneaded in the presence of the foaming agent, by A method of manufacturing foamed sheets as extruded foams from the extrusion and foaming of a T-die installed at the front end of the extruder, and then cutting the foamed sheets into pellets to manufacture foamed particles; And (3) The resin composition is supplied to the extruder and melted and kneaded in the presence of the blowing agent, and foamed by extrusion from a circular die installed at the front end of the extruder An annular extruded foam is produced, the annular extruded foam is continuously cut between the inner and outer peripheral surfaces in the extrusion direction to produce a foamed sheet, and the foamed sheet is cut into A method for producing expanded particles in granular form, etc.

(Foam molding)

The foamed molded article can be obtained by foaming and molding the above-mentioned expanded particles in a mold.

Various densities can be adopted for the foamed molded article. For example, a density of 0.05 to 0.7 g/cm ³ can be used. The density is preferably 0.07 to 0.6 g/cm ^{3, and particularly} preferably 0.08 to 0.5 g/cm ³ .

Because the foam molding system has excellent light weight, heat resistance, cushioning properties and mechanical strength, especially excellent load resistance and dimensional stability in a high temperature environment, it can be suitably used in, for example, automobiles, aircraft, railway vehicles and Parts of transportation machinery such as ships. Automobile parts can be suitably used, for example, parts used near the engine, exterior trim materials, heat insulating materials, and the like.

Examples of skin materials include fiber reinforced materials, metal sheets, and synthetic resin films. When a fiber reinforced material is used as a skin material, it is referred to as a resin composite in this specification and will be described separately in the following items.

The metal sheet system is not particularly limited, and examples thereof include aluminum sheets, stainless steel sheets, iron sheets, steel sheets, and titanium sheets. Among them, since both lightness and mechanical strength are excellent, an aluminum sheet is preferred. In addition, aluminum sheets also include aluminum alloy sheets containing 50% by mass or more of aluminum. When the thickness of the metal sheet is too thin, the mechanical strength may decrease, and when the thickness is too thick, the lightness decreases, so 0.1 to 0.5 mm is preferred, and 0.2 to 0.5 mm is preferred.

The synthetic resin film system is not particularly limited, and examples include polyolefin resin films such as polyethylene resin films and polypropylene resin films, polyester resin films such as polyethylene terephthalate films, and acrylic resin films. Wait.

The foam molding system is not particularly limited, and various shapes can be adopted according to the application.

(Manufacturing method of foam molding)

The foamed molded product can be manufactured using a method including the following steps: a filling step of filling the foamed particles in the cavity of the mold; and the secondary foaming of the foamed particles so that the obtained secondary foamed particles are mutually borrowed The foaming step of integrating by heat fusion to obtain a foamed molded body.

(A) Filling step

The method of filling the expanded particles in the cavity of the molding die of the expansion molding machine is not particularly limited. The foam molding machine can be used when manufacturing foamed molded articles from expanded particles made of polystyrene resin, and used when manufacturing foamed molded articles from expanded particles made of polypropylene resin. The high-pressure molding machine, etc.

The expanded particles can be further impregnated with inert gas to increase the foaming power. By increasing the foaming force, the thermal fusion of the foamed particles during foaming in the mold is improved, and the resulting foamed molding system has better mechanical strength. In addition, examples of the above-mentioned inert gas include carbon dioxide, nitrogen, helium, argon, etc., and carbon dioxide is preferred.

The method of impregnating the expanded particles with an inert gas includes, for example, a method of placing the expanded particles in an inert gas environment with a pressure higher than normal pressure. In this case, the expanded particles can be impregnated with inert gas before filling the mold, or after the expanded particles are filled into the mold, they can be placed in an inert gas environment together with the mold to foam The particles are impregnated with inert gas.

The temperature when the expanded particles are impregnated with the inert gas is preferably 5 to 40°C. When the temperature is lower than 5°C, the expanded particles are excessively cooled, and the expanded particles cannot be sufficiently heated during the foaming and molding in the mold, and the thermal fusion between the expanded particles is reduced, and the resulting expanded molded product may become A situation where the mechanical strength is reduced. When the temperature is higher than 40°C, the amount of inert gas impregnated in the expanded particles may be low, and sufficient expandability may not be imparted to the expanded particles, and the crystallization of the expanded particles may be promoted and the expanded particles may be thermally fused When the properties are reduced, the mechanical strength of the resulting foamed molded product is reduced. The temperature is preferably 10 to 30°C.

In addition, the pressure when impregnating the expanded particles with the inert gas is preferably 0.2 to 2.0 MPa. When the pressure is less than 0.2 MPa, the amount of inert gas impregnated in the expanded particles may decrease, and sufficient expandability may not be imparted to the expanded particles, and the mechanical strength of the resulting expanded molded article may decrease. When it exceeds 2.0 MPa, the degree of crystallinity of the expanded particles may increase, the thermal fusion properties of the expanded particles may decrease, and the mechanical strength of the resulting foamed molded article may decrease. The pressure is preferably 0.25 to 1.5 MPa. When the inert gas is carbon dioxide, it is preferably 0.2 to 1.5 MPa, preferably 0.25 to 1.2 MPa.

Moreover, the time for impregnating the expanded particles with inert gas is preferably 10 minutes to 72 hours. When the time is less than 10 minutes, the expanded particles may not be sufficiently impregnated with inert gas. If it is longer than 72 hours, the production efficiency of the foamed molded product may decrease. The time is preferably 15 minutes to 64 hours, and particularly preferably 20 minutes to 48 hours. When the inert gas is carbon dioxide, 20 minutes to 24 hours is preferred.

In this way, by impregnating the expanded particles with an inert gas at a pressure of 5 to 40°C and a pressure of 0.2 to 2.0 MPa, the increase in the crystallinity of the expanded particles can be suppressed and the foamability can be improved. Therefore, the foam is expanded in the mold During molding, the expanded particles can be thermally fused and integrated with each other strongly with sufficient foaming force, and a foamed molded product having excellent mechanical strength can be obtained.

After the expanded particles are impregnated with an inert gas according to the above-mentioned method, the expanded particles can be pre-expanded to become pre-expanded particles. The pre-expanded particles are filled into the cavity of the mold and heated to make the pre-expanded particles. The expanded particles are expanded, and the expanded molded body is formed. In addition, it is also possible to further impregnate the pre-expanded particles with an inert gas in accordance with the same procedure as that for impregnating the expanded particles with an inert gas.

The method of pre-expanding expanded particles to obtain pre-expanded particles includes, for example, a method of foaming expanded particles impregnated with an inert gas to 55 to 90°C. Since expanded particles may shrink or have poor fusion when the heating time is longer, it is desirable to use a medium that can impart high energy in a short time for heating. This medium is preferably water vapor. The pressure of water vapor is preferably 0.1 to 0.8 MPa gauge pressure. In addition, the heating time is preferably 5 to 600 seconds.

(B) Foaming step

The heating medium system of the expanded particles for secondary foaming is not particularly limited, and other than water vapor, hot air, warm water, etc. may be mentioned.

When the heating medium for the secondary foaming is water vapor, it is better to perform it under the conditions of a gauge pressure of 0.1 to 0.8 MPa and a heating time of 5 to 600 seconds.

From the viewpoint of promoting the crystallization of the foamed molded body and improving the heat resistance of the foamed molded body, it is preferable to provide a step of keeping the foamed molded body heat in the molding die after the foaming step. For example, when molding a foamed molded product with a size of 300 mm in the longitudinal direction × 400 mm in the transverse direction × 30 mm in height, the heat retention time is preferably 10 to 1000 seconds.

(Resin composite)

The resin composite has the above-mentioned foamed molded body and a fiber reinforced resin layer (skin material) laminated on the surface of the foamed molded body and integrated.

The resin composite system has more excellent heat resistance and mechanical strength, and can be used in a wide range of parts for transportation equipment and components for transportation equipment including structural components that constitute the main body of transportation equipment such as automobiles, aircraft, railway vehicles, and ships. , Can also be suitably used as construction materials, windmill blades, robot arms, cushioning materials for helmets, agricultural production boxes, thermal and cold storage containers and other transport containers, rotor blades of industrial helicopters, and parts packaging materials. The structural members constituting the car body include, for example, door panels, door inner panels, bumpers, fenders, fender supports, engine covers, roof panels, trunk lids, floor panels, Center tunnel, crash box, cowl, etc. For example, when a resin composite is used for a door panel made of steel plate in the past, a door panel having roughly the same rigidity as a steel plate door panel can be significantly reduced in weight, so that a high effect of reducing the weight of an automobile can be obtained.

The fiber system constituting the fiber-reinforced resin layer is not particularly limited, and examples thereof include carbon fiber, glass fiber, aramid fiber, boron fiber, and metal fiber. Among them, carbon fiber, glass fiber, and aramid fiber are preferred because of their excellent mechanical strength and heat resistance, and carbon fiber is preferred.

The form of the fiber is not particularly limited. Examples include woven fabrics, knitted fabrics, non-woven fabrics, and fiber bundles (strands) made by doubling the fibers in one direction. Synthetic resin yarns such as polyamide resins and polyester resins or Face materials, etc. made by bundling (stitching) stitched yarns such as glass fiber yarns. The weaving method of the woven fabric may include plain weave, twilled weave, and satin weave.

The fiber can be (1) a multi-layered material formed by laminating multiple sheets of woven fabric, knitted fabric or non-woven fabric with each other or these in any combination; and (2) fiber bundles (strands) made by doubling the fibers in one direction ) Use synthetic resin yarns such as polyamide resin and polyester resin or stitch yarns such as glass fiber yarns to bind (sew) to form a plurality of face materials, and the plurality of face materials are directed in mutually different directions with the fiber direction of the fiber bundle In this way, the laminated surface materials are integrated (sewn) by using synthetic resin yarns such as polyamide resin and polyester resin or sewing yarns such as glass fiber yarns.

Examples of the resin contained in the fiber-reinforced resin layer include uncured thermosetting resins and thermoplastic resins. The thermosetting resin is not particularly limited, and examples include epoxy resins, unsaturated polyester resins, phenol resins, melamine resins, polyurethane resins, silicone resins, maleimide resins, and vinyl esters. Resins, cyanate ester resins, resins formed by prepolymerizing maleimide resin and cyanate ester resin, etc. Because of its excellent heat resistance, elastic modulus and chemical resistance, epoxy resin and vinyl ester resin are preferred. The thermosetting resin may contain additives such as a curing agent and a curing accelerator. In addition, the thermosetting resin may be used alone or in combination of two or more kinds.

The thermoplastic resin is not particularly limited, and examples thereof include polyolefin resins such as polyethylene resins and polypropylene resins, acrylic resins, and the like.

The resin content in the fiber-reinforced resin layer is preferably 20 to 70% by mass. When the content is less than 20% by mass, the bonding between fibers may become weak and the mechanical strength of the resulting resin composite may decrease. When it is more than 70% by mass, the amount of resin existing between the fibers becomes too much, and on the contrary, the mechanical strength of the fiber-reinforced resin layer may decrease and the mechanical strength of the resulting resin composite may decrease. The content is preferably 30 to 60% by mass.

The method of impregnating the fiber with resin is not particularly limited. For example, (1) the method of impregnating the fiber in the resin; and (2) the method of applying the resin to the fiber.

The method of laminating and integrating the fiber-reinforced resin layer on the surface of the foamed molded body is not particularly limited. For example, the following methods can be mentioned: (1) The fiber-reinforced resin layer is laminated on the surface of the foamed molded body via an adhesive. Method of integration; (2) Laminating the fiber-reinforced resin impregnated with thermoplastic resin on the surface of the foamed molded body, and using the thermoplastic resin as a binder to laminate and integrate the surface of the foamed molded body and the fiber-reinforced resin layer Method; (3) Laminating a fiber-reinforced resin impregnated with an unhardened thermosetting resin on the surface of the foamed molded product, and the cured product of the thermosetting resin is used as a binder to strengthen the surface of the foamed molded product and the fiber A method of laminating and integrating the resin layer; and (4) Laminating the fiber-reinforced resin that has been heated to a softened state on the surface of the foamed molded body, and the fiber-reinforced resin layer is pressed against the surface of the foamed molded body. The surface of the foamed molded product and the fiber reinforced resin layer are laminated and integrated. In the method (4), the fiber-reinforced resin layer can also be deformed along the surface of the foamed molded article. Here, since the foamed molded article of the present invention has excellent load resistance in a high-temperature environment, the method (4) can also be suitably used.

The method used for forming the fiber-reinforced resin layer includes, for example, the autoclave method, the hand lay-up method, the spray up method, and the PCM (Prepreg Compression). Molding) method, RTM (Resin Transfer Molding) method, VaRTM (Vacuum assisted Resin Transfer Molding) method, etc.

[Example]

Next, examples are given to explain the present invention in more detail, but the present invention is not limited by these examples.

[Intrinsic viscosity (IV value)]

The intrinsic viscosity (IV value) of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin is a value measured in accordance with JIS K7367-5:2000. Specifically, the resin was dried for 15 hours at a vacuum degree of 133 Pa and 40°C.

0.1000 g was taken out of the resin as a sample and added to a 20 mL measuring flask, and about 15 mL of a mixed solvent (50% by mass of phenol and 50% by mass of 1,1,2,2-tetrachloroethane) was added to the measuring flask. The sample in the measuring flask was placed on a hot plate and heated to about 130°C to melt it. After melting the sample, it was cooled to room temperature and prepared so that the volume became 20 mL to produce a sample solution (sample concentration: 0.500 g/100 mL).

After supplying 8 mL of the sample solution to the viscometer using a whole pipette, and stabilizing the temperature of the sample using a water tank filled with 25°C water, the flow time of the sample was measured. Regarding the concentration change of the sample solution, 8 mL of the mixed solvent was sequentially added to the viscometer, mixed and diluted to produce a diluted sample solution. Furthermore, the running time of the diluted sample solution is measured. In addition to the sample solution, the flow time of the above-mentioned mixed solvent was also measured.

The inherent viscosity of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin was calculated according to the following calculation formula. The following are calculated from the flow time (t ₀ ) of the mixed solvent and the flow time (t) of the sample solution.

Relative viscosity (η _r )=t/t ₀

Specific viscosity (η _sp )=(tt ₀ )/t ₀ =η _r-1

Reduction viscosity = η _sp /C

From the measurement results of the diluted sample solution in which the concentration C (g/100mL) of the sample solution was variously changed, the vertical axis was used as the reduced viscosity and the horizontal axis was used as the concentration C of the sample solution to create a graph. From the linear relationship obtained Extrapolate to the longitudinal intercept of C=0 to obtain the intrinsic viscosity [η].

[Melting point and glass transition temperature of crystalline aromatic polyester resin and amorphous aromatic polyester resin]

The melting points of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin are measured using the method described in JIS K7121:1987 and JIS K7121:2012 "Measuring Method for Transition Temperature of Plastics". However, the sampling method/temperature conditions are as follows. Fill the sample with 5.5±0.5 mg so that there is no gap at the bottom of the aluminum measuring container, and then close the aluminum lid. Next, using the differential scanning calorimetry instrument "DSC7000X, AS-3" manufactured by SII Nano Technology, the temperature was raised from 30°C to 290°C under the conditions of a nitrogen flow rate of 20 mL/min (the first heating step). After the temperature was maintained for 10 minutes, the sample was taken out from the heating furnace and left to cool to 30°C in an air environment at 25°C. After this heat treatment, the DSC curve when the temperature was raised from 30°C to 290°C (the second heating step) was obtained. In addition, all the temperature rises were performed at a rate of 10°C/min, and alumina was used as the reference material.

In the present invention, the melting temperature (melting point) is set as the temperature at the top of the melting peak that can be observed in the second heating step using the analysis software attached to the device.

In addition, in the present invention, regarding the glass transition temperature, the stepwise changes in the glass transition that can be observed in the second heating step are calculated using the analysis software attached to the device to calculate the intermediate point glass transition temperature and use it as glass Transfer temperature. In addition, the intermediate point glass transition temperature is calculated in accordance with the specifications (9.3 "Method for Obtaining Glass Transition Temperature").

[Bulk density of expanded particles]

Measure the bulk density of expanded particles according to JIS K6911: 1995 "General Test Methods for Thermosetting Plastics". The measurement is carried out using an apparent density measuring device conforming to JIS K6911: 1995, and the bulk density of the expanded particles is obtained according to the following formula.

The volume density of the expanded particles (g/cm ³ )=[the mass of the measuring cylinder with the expanded particles (g)-the mass of the measuring cylinder (g)]/[the capacity of the measuring cylinder (cm ³ )]

[Continuous cell rate of expanded particles]

The open cell ratio of the expanded particles was measured according to the following method. First, a sample cup of a volume-measuring air-comparative hydrometer is prepared, and the total mass A (g) of the expanded particles that fills about 80% of the sample cup is measured. Next, the volume B (cm ³ ) of the entire expanded particles was measured in accordance with the 1-1/2-1 atmospheric pressure method using a hydrometer. In addition, the measurement system used Tokyo Science Corporation's "Volume Measurement Air Comparator 1000".

Next, a metal mesh container is prepared, this metal mesh container is immersed in water, and the mass C (g) of the metal mesh container in the state immersed in water is measured. Next, after adding the total amount of expanded particles to the metal mesh container, the metal mesh container is immersed in water, and the metal mesh container in the state of being immersed in water and the metal mesh container added to the metal mesh container are measured. The total mass of the expanded particles in the container is D (g). In addition, the quality of the expanded particles and the metal mesh container was measured using "Electronic Balance HB3000" (minimum scale 0.01g) manufactured by Yamato Controls & Balance Co., Ltd.

Furthermore, the apparent volume E (cm ³ ) of the expanded particles is calculated according to the following formula, and the apparent volume E and the volume B (cm ³ ) of the entire expanded particles are calculated according to the following formula. Continuous bubble rate. In addition, the volume of 1 g of water is 1 cm ³ . In addition, in this measurement, the expanded particles were stored in a JIS K7100-1999 code 23/50, class 2 environment for 16 hours, and then the measurement was performed in the same environment.

E=A+(C-D)

Continuous bubble rate (%)=100×(E-B)/E

[Melting temperature Tm, crystallization temperature Tc, glass transition temperature Tg and heat of crystallization of expanded particles]

The melting temperature Tm, the crystallization temperature Tc, and the glass transition temperature Tg of the expanded particles are measured using the methods described in JIS K7121:1987 and JIS K7121:2012 "Plastic Transition Temperature Measurement Method". The heat of crystallization of the expanded particles was measured using the method described in JIS K7121: 1987 and JIS K7122: 2012 "Measuring Method of Heat of Transfer of Plastics". However, the sampling method/temperature conditions are as follows.

Fill the sample with 5.5±0.5 mg so that there is no gap at the bottom of the aluminum measuring container, and then close the aluminum lid. Next, using a differential scanning calorimetry instrument "DSC7000X, AS-3" manufactured by Hitachi High-Tech Science Co., Ltd., a DSC curve when the temperature was raised from 30°C to 290°C under the conditions of a nitrogen flow rate of 20 mL/min was obtained. In addition, the temperature increase was performed at a rate of 10°C/min, and alumina was used as a reference material.

The melting temperature Tm (melting point) and crystallization temperature Tc are set as follows: use the analysis software attached to the device and read the melting peaks and the melting peaks that can be observed in the DSC curve obtained from the first heating step shown in Figure 1 The value of the peak top temperature of the crystallization spike.

Regarding the glass transition temperature Tg, it can be calculated from the specifications (9.3 "Method for determining the glass transition temperature"). The stepwise change in the glass transition of the DSC curve obtained in the first heating step shown in Figure 1, is Calculated in the form of the intermediate point glass transition temperature. In addition, in the stepwise change portion of the glass transition of the DSC curve, when the difference Δ(mW) between the baseline on the low temperature side and the baseline on the high temperature side in the vertical axis direction is 0.02 mW or less, it is not regarded as a stepwise change in glass transition .

The heat of crystallization is calculated from the area of the crystallization peak in the DSC curve obtained in the first heating step shown in Figure 1. Specifically, as shown in Figure 1, in the obtained DSC curve, "the straight line connecting the point where the DSC curve departs from the baseline on the low temperature side and the point where the DSC curve returns to the high temperature side again" and the "DSC curve" Calculate the area of the enclosed part.

[Semi-crystallization time of expanded particles]

The semi-crystallization time at 120°C of the expanded particles measured by DSC is the time measured according to the following procedure.

Specifically, the measuring device used a differential scanning calorimetry device ("DSC7000X, AS-3" manufactured by Hitachi High-Tech Science Co., Ltd.). Fill the aluminum measuring container with approximately 5.5±0.5 mg of expanded particles so that there is no gap at the bottom. After filling, under the condition of a nitrogen flow rate of 20 mL/min, the half crystallization time was measured using alumina as a reference substance. Regarding the heat treatment conditions, the expanded particles were heated from 30°C to 290°C at a temperature increase rate of 10°C/min. After the expanded particles were held at 290°C for 10 minutes, the expanded particles were taken out from the heating furnace and Let it cool to 30°C in an air environment of 25°C. After this heat treatment, the expanded particles are heated from 30°C to 110°C at the maximum heating rate of the heating furnace (approximately 35°C/min), and further heated from 110°C to 120°C at 10°C/min, Subsequently, the heat generated by the crystallization of the resin when the expanded particles were kept at 120±1°C for 30 minutes was measured. A DSC curve with the horizontal axis as time can be obtained as shown in Figure 2. In the DSC curve, the point a at which fever starts, the point b at which the fever ends (the fastest point where the DSC curve returns to the baseline after the peak apex c), and the peak apex c of the DSC curve are specified. In addition, the point a is set as the intersection of the extension line of the baseline (the straight portion immediately after the heating peak) and the DSC curve in a state where the temperature of the measurement sample becomes 120±1°C. Here, the elapsed time T from the point a to the point c is referred to as the "semi-crystallization time of the expanded particles (thermoplastic polyester resin)". The semi-crystallization time of the expanded particles is set as follows: prepare three samples of the expanded particles, measure the semi-crystallization time of the expanded particles from each sample, and obtain the arithmetic average of the half-crystallization time of each sample value.

[Density of foamed molded product]

The density of the foamed molded article is measured using the method described in JIS K7222: 1999 "Foamed Plastics and Rubber-Measurement of Apparent Density". The foamed molded article of 50 cm ³ or more (100 cm ³ or more in the case of semi-hard and soft materials) is cut without changing the original unit structure of the material, and its mass is measured. Calculate the density according to the following formula.

Density (g/cm ³ ) = Mass of foamed molding (g) / Volume of foamed molding (cm ³ )

[The heating dimensional change rate of the foamed molded product]

The heating dimensional change rate of the foamed molded article is measured using the method B described in JIS K6767: 1999 "Foam Plastic-Polyethylene-Test Method".

A test piece whose planar shape is a square 150 mm on each side and the thickness of the foamed molded body is cut out from the molded foam. At the center of the test piece, mark three lines of 100 mm parallel to each other and spaced 50 mm apart in the vertical and horizontal directions. The lengths of three straight lines are measured for each of the vertical and horizontal directions, and the arithmetic average L0 of the same length is set as the initial size. Subsequently, the test piece was placed in a hot air circulating dryer at 130°C for 168 hours to conduct a heating test. After the heating test, the test piece was taken out and placed at 25°C for 1 hour. Next, the length of each of the three straight lines in the vertical and horizontal directions marked on the surface of the test piece is measured, and the arithmetic mean value L1 of the same length is used as the dimension after heating. The heating dimensional change rate was calculated according to the following equation.

Heating size change rate (%)=100×(L1-L0)/L0

[Mechanical properties of foam molding: maximum point load, maximum point stress, maximum point energy and elastic modulus]

Five rectangular parallelepiped test pieces measuring 20 mm in length x 25 mm in width x 130 mm in height were cut out from the molded foam. For each test piece, a bending test was performed in accordance with JIS K7221-1. The measurement system used a Tensilon universal testing machine ("UCT-10T" manufactured by ORIENTEC). The maximum point load, maximum point stress, maximum point displacement, and maximum point energy are calculated using the universal testing machine data processing system ("UTPS-237S Ver, 1.00" manufactured by Softbrain). The arithmetic average of the maximum point load, maximum point stress, maximum point energy, and elastic modulus of each test piece is regarded as the maximum point load, maximum point stress, maximum point energy, and elastic modulus, respectively.

[Judgment criteria for heat resistance evaluation of molded foam]

From the measurement result of the heating dimensional change rate of 130°C of the above-mentioned foamed molded article, the evaluation was performed based on the following criteria.

◎: The heating dimensional change rate is greater than -0.5% and less than +0.5%

○: The heating dimensional change rate is greater than -1.0% and less than -0.5% and is greater than +0.5% and less than +1.0%

×: Heating dimensional change rate -1.0% or less or +1.0% or more

[Judgment criteria for evaluation of mechanical properties of foamed molded products]

From the mechanical properties of the above-mentioned foam, it was evaluated based on the following criteria.

◎: The maximum point stress is 1.2MPa or more

○: The maximum point stress is 1.0MPa or more and less than 1.2MPa

×: None of the above "◎" and "○" criteria are met.

[Appearance Evaluation of Foam Molded Products]

The unevenness of the boundary portion where the expanded particles on the surface of the obtained foamed molded article are joined was visually confirmed, and evaluated based on the following criteria.

⊚: The boundary portion where the expanded particles on the surface of the foamed molded article are joined is smooth.

○: The boundary portion where the expanded particles on the surface of the foamed molded article are joined to each other has slight irregularities and poor smoothness.

×: Most of the boundary portion where the expanded particles on the surface of the foamed molded article are joined to each other has unevenness and the smoothness is remarkably poor.

[Comprehensive Evaluation of Foam Molded Products]

Based on the three evaluation results of heat resistance evaluation, mechanical property evaluation, and appearance evaluation of the above-mentioned molded foam, the comprehensive evaluation of the molded foam was determined based on the following criteria.

◎: Among the three evaluation results, “◎” is 2 or more.

○: Among the three evaluation results, "◎" means less than two.

×: At least one of the three types of evaluation results is "×".

[Assessment of the compounding of resin composites]

Regarding the feasibility of compounding in the resin composite, the surface of the resin composite was visually observed and evaluated based on the following criteria. The so-called concavities and convexities on the surface of the fiber-reinforced resin layer of the resin composite are defined as the portion where the fiber-reinforced resin layer protrudes or dents by 1.0 mm or more due to uneven expansion and contraction of the foamed molded body.

○: The surface of the fiber-reinforced resin layer of the resin composite has no irregularities and has a beautiful appearance.

×: Concave and convex parts are confirmed on the surface of the fiber-reinforced resin layer of the resin composite.

[Evaluation of mechanical properties of resin composite]

When compared with the foamed molded product with poorer evaluation results of the mechanical properties of the above foamed molded product, when the foamed molded product with excellent mechanical properties of the above foamed molded product is used, confirm the mechanical properties of the composite foam Physical properties become higher. Therefore, the mechanical physical properties of the composite foam are determined based on the evaluation results of the mechanical physical properties of the above-mentioned foamed molded article and based on the following criteria.

○: The evaluation result of the mechanical properties of the above foamed molded product is "◎" or "○"

×: The evaluation result of the mechanical properties of the foamed molded article is "×"

[Comprehensive Evaluation of Resin Complex]

From two of the above-mentioned evaluation results of the feasibility of compounding in the resin composite and the evaluation results of the mechanical properties of the above-mentioned resin composite, the comprehensive evaluation of the resin composite is determined based on the following criteria.

○: Both evaluation results are "○"

×: At least one evaluation result is "×"

In the Examples, Comparative Examples, and Reference Examples, the following crystalline aromatic polyester resins, amorphous aromatic polyester resins, bubble modifiers, and crosslinking agents were used.

(A) Crystalline aromatic polyester resin: resin a

(a) Polyethylene terephthalate (PET)

Product name "Mitsui PET SA-135" manufactured by Mitsui Chemicals

IV value=0.88, melting point Tm=247℃, glass transition temperature Tg=78℃

(b) Polyethylene naphthalate (PEN): resin b

Teijin Corporation product name "Teonex TN8050SC"

IV value=0.51, melting point Tm=265℃, glass transition temperature Tg=120℃

(B) Amorphous aromatic polyester resin

(c) CHDM copolymerized PET (PETG): resin c

Product name "Eastar copolyester GN001" made by EASTMAN CHEMICAL

IV value=0.75, glass transition temperature Tg=78℃

Contains 33mol% 1,4-cyclohexanedimethanol as the diol component

(d) CHDM copolymerized PET (PETG): resin d

Product name "Eastar copolyester GN401" made by EASTMAN CHEMICAL

IV value=0.67, glass transition temperature Tg=79℃

Containing 16mol% 1,4-cyclohexanedimethanol as the diol component

(e) CHDM copolymerized PET (PETG): resin e

Product name "Eastar copolyester 5011" manufactured by EASTMAN CHEMICAL

IV value=0.59, glass transition temperature Tg=80℃

Contains 15mol% 1,4-cyclohexanedimethanol as the diol component

(f) NPG copolymerized PET: resin f

Product name "Bell PET E-02" manufactured by Bell Polyester Products

IV value=0.79, glass transition temperature Tg=75℃

Contains 16mol% neopentyl glycol as the glycol component

(g) CHDM and TMCD copolymerization PET (PCT): resin g

Product name "Tritan FX-200" manufactured by EASTMAN CHEMICAL

IV value=0.64, glass transition temperature Tg=118℃

Containing 65mol% of 1,4-cyclohexanedimethanol and 35mol% of 2,2,4,4-tetramethyl-1,3-cyclobutanediol as the diol component

(C) Air bubble regulator

Product name "PET-F40-1" manufactured by Terabo

Masterbatch made of polyethylene terephthalate containing talc

(Polyethylene terephthalate content: 60% by mass, talc content: 40% by mass)

(D) Crosslinking agent

Made by Daicel Company, Pyromellitic Anhydride

(Example 1)

(1) Manufacturing of expanded particles

The production equipment shown in FIGS. 3 to 5 was used to produce expanded particles according to the following procedures.

First, the predetermined amounts of resin a, resin c, air bubble regulator, and crosslinking agent shown in Table 1 are supplied to a uniaxial extruder with a diameter of 65 mm and an L/D ratio of 35, and melt-kneaded at 290°C .

Next, from the middle of the extruder, the butane composed of 35% by mass of isobutane and 65% by mass of n-butane was made 0.5 parts by mass relative to 100 parts by mass of the total amount of resin a and resin c The resin composition is pressed into a molten state and uniformly dispersed in the resin composition.

After that, the molten resin composition is cooled to 250° C. at the tip of the extruder, and then the resin composition is extruded and foamed from each nozzle of the multi-nozzle mold 1 installed at the tip of the extruder. The extrusion amount of the resin composition was 30 Kg/hour.

In addition, the nozzle mold 1 is a nozzle with 20 outlets 11 with a diameter of 1 mm. The outlets 11 of the nozzle are all arranged at regular intervals on the front end surface 1a of the nozzle mold 1. The assumed diameter is 139.5 mm. On the imaginary circle A. Moreover, on the outer peripheral surface of the rear end of the rotating shaft 2, two rotating blades 5 are integrally arranged in the circumferential direction of the rotating shaft 2 with a phase difference of 180°, and each rotating blade 5 is designed to contact the nozzle mold 1 frequently. The state of the front end surface 1a is configured to move on the virtual circle A.

Furthermore, the cooling member 4 is provided with a cooling drum 41 formed from a front part 41a having a front circular shape; and a cylindrical peripheral wall part extending from the outer periphery of the front part 41a toward the rear and having an inner diameter of 320mm 41b. The cooling water 42 at 20° C. is supplied into the cooling drum 41 through the supply pipe 41 d and the supply port 41 c of the cooling drum 41. The volume in the cooling drum 41 is 17684 cm ³ .

The cooling water 42 is drawn spirally along the inner peripheral surface of the peripheral wall portion 41b of the cooling drum 41 by centrifugal force accompanied by the flow velocity when it is supplied from the supply pipe 41d to the inner peripheral surface of the peripheral wall portion 41b of the cooling drum 41 The cooling liquid 42 travels along the inner peripheral surface of the peripheral wall portion 41b, and gradually expands in a direction orthogonal to the direction of travel. As a result, the cooling drum 41 is further forward than the supply port 41c. The inner peripheral surface of the peripheral wall portion 41b is in a state where the entire surface is covered by the coolant 42.

The rotating blade 5 arranged on the front end surface 1a is rotated at a speed of 2500 rpm, and the resin extruded product extruded and foamed from the outlet 11 of each nozzle of the nozzle mold 1 is cut by the rotating blade 5 to produce a rough ball Shaped granular cuts. The resin extruded product is composed of an unfoamed part immediately after being extruded from the nozzle of the nozzle die 1 and a foamed part in the middle of foaming following the unfoamed part. In addition, the resin extruded product is cut at the opening end of the outlet portion 11 of the nozzle, and the resin extruded product is cut at the unfoamed portion.

In the production of the aforementioned expanded beads, first, the rotating shaft 2 is not attached to the nozzle mold 1 and the cooling member 4 is retracted from the nozzle mold 1 in advance. In this state, the resin extruded product is extruded and foamed from the extruder, and it is confirmed that the resin extruded product is formed from the unfoamed part just after being extruded from the nozzle of the nozzle die 1 and the subsequent unfoamed part. The foaming part is formed during the foaming process. Next, after mounting the rotating shaft 2 on the nozzle mold 1 and arranging the cooling member 4 at a predetermined position, the rotating shaft 2 is rotated and a rotating blade 5 is used to cut the resin extruded product at the opening end of the nozzle outlet 11 Produce granular cuts.

The granular cut material is scattered toward the outside or front by the cutting stress generated by the rotating blade 5, and the cooling water 42 flowing along the inner surface of the cooling drum 41 of the cooling member 4 is removed from the cooling water 42 The upstream side of the flow of 42 follows the cooling water 42 toward the downstream side and collides from the direction oblique to the surface of the cooling water 42, and the granular cut material enters the cooling water 42 and is immediately cooled to produce a hair Bubble particles.

The obtained expanded particles are discharged together with the cooling water 42 through the discharge port 41e of the cooling drum 41, and are separated from the cooling water 42 by a dehydrator.

(2) Manufacturing of foam molding

Prepare an in-mold foam molding machine with molds (male mold and female mold). In a state where the male mold and the female mold are closed, a rectangular parallelepiped cavity with an internal dimension of 300 mm in the longitudinal direction × 400 mm in the transverse direction × 30 mm in height is formed between the male and the male molds.

Furthermore, in a state where the mold was cracked to 3 mm, the expanded particles were filled in the mold, and then steam was introduced from the female mold to 0.05 MPa (gauge pressure) in the cavity for 30 seconds. Next, the steam was The male mold is introduced for 30 seconds so that the mold cavity becomes 0.05 MPa (gauge pressure). Secondly, water vapor is supplied from the male and female molds so that the mold cavity becomes 0.1 MPa (gauge pressure) for 30 seconds to foam The particles are heated to secondarily expand them, and the secondary expanded particles are thermally fused and integrated. Then, after stopping the introduction of steam into the mold cavity and holding it for 300 seconds (heat retention step), finally cooling water is supplied into the mold cavity to cool the foamed molded body in the mold, and then the mold cavity is opened. Take out the foamed molded body.

At this time, from the step of filling the expanded particles in the mold, the time (molding cycle time) required to obtain the expanded molded body was 600 seconds.

(3) Manufacturing of resin composite

Prepare a fiber-reinforced base material formed from a woven fabric of a twill weave made of carbon fibers containing 40% by mass of uncured epoxy resin as a thermosetting resin. A fiber-reinforced resin layer forming material (CFRP, "PYROFIL PREPREG TR3523 381GMP" manufactured by Mitsubishi Rayon Corporation, unit area weight: 200g/m ² ). The fiber-reinforced resin layer forming material was laminated on the surface of the foamed molded body and integrated with the fiber-reinforced resin layer forming material using the autoclave method. Specifically, a pressure of 0.3 MPa gauge pressure is applied to the laminate while heating the laminate at 130°C for 60 minutes to harden the thermosetting resin in the fiber-reinforced resin layer forming material while strengthening the fibers The resin layer forming material is laminated and integrated on both areas of the foamed molded body by the cured thermosetting resin.

(Examples 2 to 8)

Except that the ratio of the crystalline aromatic polyester resin and the amorphous aromatic polyester resin and the type of the amorphous aromatic polyester resin are set as shown in Table 1, the same as in Example 1 It proceeds to obtain expanded particles and expanded molded articles.

(Comparative example 1)

Except that the crystalline aromatic polyester resin a was set to 60% by mass and the amorphous aromatic polyester resin c was set to 40% by mass, the same procedure as in Example 1 was carried out to obtain expanded particles and Foam molding.

When measuring the half crystallization time of the obtained expanded particles at 120°C, the half crystallization time could not be calculated because the crystallization was not completed within the measurement time (the exothermic peak in the DSC curve did not return to the baseline).

(Comparative example 2)

Except that only the crystalline aromatic polyester-based resin a was used and the amorphous aromatic polyester-based resin was not used, the same procedure as in Example 1 was carried out to obtain expanded particles and expanded molded articles.

(Comparative example 3)

Except for using resin g as the amorphous aromatic polyester-based resin, the same procedure as in Example 1 was carried out to obtain expanded particles and expanded molded articles.

When the obtained expanded beads were measured by DSC, two glass transition temperatures Tg were observed in the DSC curve.

(Comparative Example 4)

Except for using only the crystalline aromatic polyester-based resins a and b, the same procedure as in Example 1 was carried out to obtain expanded particles and expanded molded articles.

When the obtained expanded particles were measured by DSC, the crystallization peak and the melting peak in the DSC curve were close to each other and a baseline could not be drawn, so the heat of crystallization could not be calculated.

When measuring the half crystallization time of the obtained expanded particles at 120°C, the half crystallization time could not be calculated because the crystallization was not completed within the measurement time (the exothermic peak in the DSC curve did not return to the baseline).

The heating dimensional change rate of the obtained foamed molded body cannot be calculated because the heated foamed molded body is greatly deformed.

(Reference example 1)

Except that the expanded particles obtained in Comparative Example 4 were used, the heat retention step during the production of the expanded molded product was set to 900 seconds, and the molding cycle time was set to 1200 seconds. The same procedure was followed as in Example 1. Thus, a foamed molded body is obtained.

The blending ratio, the evaluation results of the expanded particles, the molding conditions of the molded foam, the evaluation results of the molded foam, and the evaluation results of the resin composite are shown in Tables 1 and 2 below.

From Examples 1 to 8 in Table 1 and Table 2, it is known that the expanded particles exhibit the following properties: (1) the aforementioned DSC curve shows a glass transition temperature and a crystallization peak, (2) from The heat of crystallization obtained from the area of the aforementioned crystallization peak is 20mJ/mg or more, and (3) the semi-crystallization time at 120°C is 180 to 1000 seconds, and the beautiful appearance and excellent heat resistance and mechanical strength can be obtained.的foaming molded body.

Claims (11)

An expanded particle, which is an expanded particle of a thermoplastic aromatic polyester resin composition, wherein the thermoplastic aromatic polyester resin composition contains a crystalline aromatic polyester resin and exhibits an inherent viscosity of 0.6 to 1.1 (IV value) Amorphous aromatic polyester resin, the aforementioned expanded particle system shows the following properties in the DSC curve obtained when heated from 30°C to 290°C at a heating rate of 10°C/min: ( 1) The aforementioned DSC curve shows a glass transition temperature and a crystallization peak; (2) The heat of crystallization calculated from the area of the aforementioned crystallization peak is 20mJ/mg or more; and (3) Half of 120°C The crystallization time is 180 to 1000 seconds. The expanded particles described in item 1 of the scope of patent application, wherein the aforementioned expanded particles show an open cell ratio of less than 15%. The expanded particles described in the first item of the scope of patent application, wherein, relative to the total of 100% by mass of the aforementioned crystalline aromatic polyester resin and amorphous aromatic polyester resin, 65 to 99% by mass and The ratio of 35 to 1% by mass contains the aforementioned crystalline aromatic polyester resin and amorphous aromatic polyester resin. The expanded particle according to the first item of the scope of patent application, wherein the aforementioned amorphous aromatic polyester resin system exhibits a glass transition temperature of 60 to 90°C. The expanded particle according to the first item of the patent application, wherein the difference between the glass transition temperature of each of the amorphous aromatic polyester resin and the crystalline aromatic polyester resin is 15°C or less. The expanded particle according to the first item of the patent application, wherein the aforementioned crystalline aromatic polyester resin is selected from polyethylene terephthalate, polyethylene naphthalate, and polyethylene terephthalate Ding One or more of diester, polytrimethylene terephthalate, and polytrimethylene naphthalate, the aforementioned amorphous aromatic polyester resin is terephthalic acid and 1,4-cyclohexanedimethanol and / Or a copolymer of neopentyl glycol. A foamed molded product obtained by foaming and molding the expanded particles described in item 1 of the scope of patent application in a mold. A resin composite is provided with the foamed molded body described in claim 7 and a fiber-reinforced resin layer laminated on the surface of the foamed molded body and integrated. A method for producing expanded particles, which is the method for producing expanded particles described in item 1 of the scope of the patent application. The method includes the following steps: containing a crystalline aromatic polyester resin and exhibiting a characteristic of 0.6 to 1.1 The thermoplastic aromatic polyester resin composition of the amorphous aromatic polyester resin of viscosity (IV value) is supplied to the extruder, and the supply supplied to the aforementioned extruder is carried out in the presence of a blowing agent The melt extrusion step of extruding and foaming while melt kneading to obtain an extruded foam; and the cutting step of cutting the aforementioned extruded foam to obtain expanded particles. The method for producing expanded particles as described in the scope of patent application, wherein the ratio is 65 to 99% with respect to the total of 100% by mass of the aforementioned crystalline aromatic polyester resin and amorphous aromatic polyester resin. The content ratio of mass% and 35 to 1 mass% contains the aforementioned crystalline aromatic polyester resin and amorphous aromatic polyester resin. A method for manufacturing a foamed molded body includes the following steps: a filling step of filling the foamed particles described in item 1 of the scope of the patent application into the cavity of a mold; and the second foaming of the foamed particles and the The obtained secondary expanded particles are integrated by heat fusion to obtain a foaming step of a foamed molded body.

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