JPH0948876A - Thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic resin composition, containing a thermoplastic resin, a specific cyclic inulooligosaccharide and an inorganic filler in a specified proportion, excellent in mechanical characteristics, heat and chemical resistances, moldability and mechanical properties in recycling use and useful as automotive parts, etc. SOLUTION: This thermoplastic resin composition contains (A) 100 pts.wt. thermoplastic resin such as a polyamide, a saturated polyester or an α,β-unsaturated carboxylic acid-modified polyolefin, (B) 0.01-5 pts.wt. cyclic inulooligosaccharide of the formula [(n) is 6-8] [e.g. a substance prepared by reacting inulin or vegetable plant extract, obtained from a rhizome of Helianthus tuberosus L. or Cichorium intybus L. and containing the inulin with an enzyme capable of producing a cyclofructan (a cycloinulooligosaccharide fructanotransferase)] and (C) 0-160 pts.wt. inorganic filler such as a glass fiber, aluminum hydroxide or mica.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has good mechanical properties, heat resistance, and chemical resistance, and is easy to perform general molding such as blow molding, extrusion molding, and injection molding even when used for recycling, and is also recycled molding. The present invention relates to a thermoplastic resin composition having good mechanical properties and the like.

[0002]

2. Description of the Related Art Since thermoplastic resins have excellent mechanical properties and molding processing properties, their range of use is widely expanded in many industrial fields at present. For example, in the parts of automobiles, general machines, precision machines, optical machines, home appliances, etc., metal and light alloy castings have hitherto been the mainstream, but recently, due to market needs, weight reduction, economic efficiency, mass productivity, function It tends to be replaced by a plastic material having excellent properties. Moreover, in such a current situation, the heat resistance is high,
Many thermoplastic composite resins with excellent physical properties such as mechanical strength, chemical resistance, and slidability have been developed according to the required performance in various fields of application.Even though these thermoplastic composite resins are used, In order to respond to more sophisticated needs, a thermoplastic composite resin that improves various physical properties, has little deterioration in various physical properties during recycling, and has good molding stability during recycling. Development is needed.

Specifically, in large-sized hollow molded parts, particularly in automobile fuel tanks, oil tanks, etc., thermoplastic resin is important because chemical resistance, rigidity, impact resistance and molding processability are important performances. Among them, based on polyamide, the performance is improved by adding various fiber-based reinforcing fillers, powder-type inorganic fillers and various additives. However, since polyamide has a low melt tension, parison drawdown during blow molding is severe, and it is difficult to obtain a large blow molded product by itself. As a method for improving such a problem, a composition in which a polyphenylene ether and an α, β-unsaturated carboxylic acid-modified polyolefin are mixed with polyamide has been proposed.
However, these techniques improve the mechanical properties and moldability by the structure in which the polyphenylene ether and the α, β-unsaturated carboxylic acid-modified polyolefin are dispersed as microdomains in the matrix of polyamide, and therefore, In general thermoplastic resin compositions by these techniques, when recycled molding is performed, the polyamide of the base polymer is decomposed due to heat history, and physical properties are significantly reduced as compared with virgin products, and the moldability also tends to be greatly deteriorated. However, the present situation is that these improvements are desired.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and has good mechanical properties, heat resistance and chemical resistance, and at the same time, it is hollow molding, extrusion molding and injection molding even at the time of recycling molding. An object of the present invention is to provide a resin composition that can be easily molded by a molding machine for general polyolefins such as molding and that has good mechanical properties of the molded product.

[0005]

[Means for Solving the Problems] As a result of intensive studies, the inventors of the present invention have found that when a specific amount of a specific cyclic inulooligosaccharide is blended with a thermoplastic resin, a good balance between impact resistance and rigidity is obtained, and molding is performed. It was found that a thermoplastic resin composition having excellent properties and recycling properties can be obtained, and the present invention has been accomplished. That is, the present invention provides the following components (A) and (B)
And (C) in the following compounding ratios. (A) 100 parts by weight of thermoplastic resin (B) 0.01 to 5 parts by weight of cyclic inulooligosaccharide represented by the following general formula (I)

Embedded image (In the formula, n represents an integer of 6 to 8) (C) Inorganic filler 0 to 160 parts by weight

As a result, automobile parts such as automobiles, fuel tanks, oil tanks, radiator duct hoses, housings for computers, printers, copiers, injection molded parts for gears, hollow products such as chemical bottles and food bottles, and It is preferably used for coating of telecommunications cables and the like, protection tubes, and extrusion / hollow molded products such as industrial / food sheets.

The present invention will be described in detail below.

(1) Thermoplastic Resin (A) The thermoplastic resin (A) used in the present invention preferably has a polar group in its molecule. Specific examples of the thermoplastic resin (A) include polyacetal, polyamide, polycarbonate, saturated polyester, styrene-acrylonitrile copolymer, polyphenylene oxide, acrylonitrile-butadiene-styrene copolymer, polyphenylene sulfide, polysulfone, polyether sulfone, Polyetherketone, polyarylate, polyoxybenzylene, polyetherimide, olefin-vinyl alcohol copolymer, methylpentene resin, α, β-unsaturated carboxylic acid or their derivatives (for example, acrylic acid,
Methacrylic acid, ethacrylic acid, maleic acid, fumaric acid, or anhydrides or esters of these acids) are graft-polymerized polyolefins. Preferred are polyamides having amide groups in the main chain, saturated polyesters having ester groups, styrene-acrylonitrile copolymers having nitrile groups, α, β-unsaturated carboxylic acid modified polyolefins, vinylsilane modified polyolefins and the like. The main thermoplastic resin (A) among these will be described below.

(1-1) Polyamide The polyamide used as the thermoplastic resin (A) in the present invention has a —CONH— bond in the polymer main chain and can be heated and melted. Typical examples are nylon 4, nylon 6, nylon 6,6, nylon 4,
6, Nylon 12, Nylon 6, 10 and the like, and other well-known aromatic diamines, aromatic dicarboxylic acids, and other low crystalline or amorphous polyamides composed of monomer components can also be used. Preferred polyamides are nylon 6 or nylon 6,6, among which nylon 6,
6 is particularly preferred. The polyamide used in the present invention preferably has a relative viscosity of 2.0 to 8.0 (measured in 98% concentrated sulfuric acid at 25 ° C.).

(1-2) Saturated polyester As a saturated polyester which is a preferred example of the thermoplastic resin (A), for example, a dicarboxylic acid or a lower alkyl ester thereof, an acid halide or an acid anhydride derivative can be prepared by a conventional method. A saturated polyester produced by condensing a glycol or a dihydric phenol may be mentioned. Specific examples of the aromatic or aliphatic dicarboxylic acid suitable for producing the saturated polyester include oxalic acid,
Malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, p, p'-dicarboxydiphenyl sulfone, p-carboxyphenoxyacetic acid, p-carboxyphenoxypropionic acid, Examples thereof include p-carboxyphenoxybutyric acid, p-carboxyphenoxyvaleric acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid and the like, or a mixture of these carboxylic acids.

As the aliphatic glycol suitable for producing the saturated polyester, a straight chain alkylene glycol having 2 to 12 carbon atoms such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6
Examples include-hexanediol and 1,12-dodecanediol. Further, as the aromatic glycol compound,
P-xylylene glycol is exemplified, and examples of the dihydric phenol include pyrocatechol, resorcinol, hydroquinone, and alkyl-substituted derivatives of these compounds. Other suitable glycols also include 1,4-cyclohexanedimethanol.

Among the saturated polyesters listed above,
Polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), poly (1,4-cyclohexanedimethylene terephthalate) (PCT), liquid crystalline polyester and the like are suitable for the thermoplastic resin composition of the present invention. It is a saturated polyester. The viscosity of the saturated polyester used here is
Phenol / 1,1,2,2-tetrachloroethane = 6
The intrinsic viscosity measured at 20 ° C. in a 0/40% by weight mixed solution is preferably in the range of 0.5 to 5.0 dl / g. More preferably 1.0 to 4.0 dl / g, and particularly preferably 2.0 to 3.
It is 5 dl / g. If the intrinsic viscosity is less than 0.5 dl / g, the impact resistance will be insufficient, and if it exceeds 5.0 dl / g, the moldability will be poor.

(1-3) α, β-Unsaturated Carboxylic Acid-Modified Polyolefin The modified polyolefin used in the present invention is a polyolefin modified by introducing an α, β-unsaturated carboxylic acid or a derivative thereof. The polyolefin serving as the base of the modified polyolefin used in the present invention includes an α-olefin homopolymer such as ethylene, propylene, butene or hexene, or a copolymer of these α-olefins. Specific examples thereof include ethylene resins such as low density polyethylene, medium density polyethylene, high density polyethylene, and ethylene-vinyl acetate copolymers; propylene resins; butene-1 resins; 4
-Methylpentene-1 type resin; ethylene-propylene copolymer and the like. Further, as these copolymerization components, dialkenylbenzene compounds such as divinylbenzene, methyl octadiene, methyl hexadiene, 1,9
-Decadiene, 1,13-tetradecadiene and other non-conjugated diene compounds, norbornene, tetracyclo [4.4.
0.1 ^2,5 . 1 ^7,10 ] -3-Dodecene and other polyolefins containing a polyunsaturated compound such as a cyclic olefin as a copolymerization component.

Α, β-used for modifying polyolefins
Specific examples of unsaturated carboxylic acids or derivatives thereof include acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, fumaric acid, hymic acid, crotonic acid, mesaconic acid, sorbic acid or their esters, and acid anhydrides. Of these, acrylic acid, methacrylic acid, and maleic anhydride are preferable, and these can be used in combination of two or more.
The amount of the α, β-unsaturated carboxylic acid or its derivative used is 0.1 to 30 parts by weight based on 100 parts by weight of the polyolefin.
It is 0 part by weight, preferably 1 to 200 parts by weight. α, β
-Unsaturated carboxylic acid or its derivative is less than 0.1 part by weight, there is almost no effect of improving the compatibility of the resin composition, and when it exceeds 300 parts by weight, the mechanical properties of the resin composition are difficult to be exhibited.

The modified polyolefin used in the present invention is
It is produced by radical graft polymerization of an α, β-unsaturated carboxylic acid or its derivative onto a polyolefin by a conventionally known method. For example, in the presence of the polyolefin and the monomer, a method of irradiating with radiation such as γ-ray and electron beam, a method of irradiating the polyolefin with radiation and then allowing the monomer to coexist, in a solution state, a molten state or a dispersed state. Any method such as coexistence of polyolefin and the monomer and graft polymerization in the presence or absence of a radical polymerization catalyst can be adopted in the present invention. Examples of radical polymerization catalysts include benzoyl peroxide, t-butyl peroxybenzoate, dicumyl peroxide, t-butyl hydroperoxide, t-butyl peroxyacetate, diisopropyl peroxydicarbonate, 2,2-bis ( Organic peroxides such as t-butylperoxy) octane and methyl ethyl ketone peroxide; inorganic peroxides such as potassium persulfide; azo compounds such as α, α′-azobisisobutyronitrile; or hydrogen peroxide Examples thereof include redox catalysts such as ferrous salts. These radical polymerization catalysts are appropriately selected in relation to the polymerization method,
One kind or two or more kinds may be used in combination. The temperature of the radical graft polymerization reaction is usually 30 to 350 ° C., preferably 50 to 300 ° C., and the polymerization time is 30 seconds to
It is in the range of 50 hours, preferably 1 minute to 24 hours. The radical polymerization catalyst is used in an amount of 0 to 10 with respect to 100 parts by weight of α, β-unsaturated carboxylic acid or its derivative.
It is appropriately selected from the range of 0 parts by weight, preferably 0 to 30 parts by weight.

(2) Cyclic inulooligosaccharide (B) The cyclic inulooligosaccharide (B) used in the present invention is an oligosaccharide in which 6 to 8 fructose are cyclically linked, and is 1989.
Discovered by Uchiyama et al. [Carbohydrate Research,
192 , 83-90 (1989), JP-A-2-252701 and JP-A-2-255085]. The cyclic inulooligosaccharide has a property of being extremely well soluble in water, unlike cyclodextrin in which 6 to 8 glucose are cyclically bonded. Cyclic inulo-oligosaccharides can be obtained by adding cyclofructan-producing enzyme (cycloinulooligosaccharide fructanotransferase: CFTase) or the same to inulin or an inulin-containing plant extract which is a main component of carbohydrates obtained from rhizomes of Jerusalem artichoke, chicory, dahlia and the like. It can be obtained by reacting a microorganism that produces an enzyme (JP-A-2-
No. 252701, No. 2-255085 and No. 4-23
No. 7496). Specifically, Bacillus circulans MZ No. 31 (National Institute for Biological Research No. 9943), Bacillus circulans MCI
-2544 (Life Science Research Institute No. 11940) or the like, or the culture supernatant is allowed to act on the inulin-containing material.
At this time, when the culture supernatant is used, it may be used as it is or after being purified. The obtained reaction liquid contains a mixture of cyclic inulooligosaccharides in which 6 to 8 fructose are cyclically linked. The cyclic inulooligosaccharide thus obtained is represented by the following general formula (I).

[0017]

Embedded image

(In the formula, n represents an integer of 6 to 8) The cyclic inulooligosaccharide used in the present invention is the cyclic inulooligosaccharide solution produced by the above-mentioned method as it is, or is separated and purified by a conventional method. Both are available.

When the cyclic inulooligosaccharide (B) is blended with, for example, a polyolefin modified with vinylsilane, α, β-unsaturated carboxylic acid or the like, it interacts with the hydroxyl group of the cyclic inulooligosaccharide (B), so that To improve physical properties such as dynamic strength and heat resistance. In addition, when a cyclic inulooligosaccharide (B) is mixed with an ordinary polyamide (for example, nylon 66), an interaction between the amide group of the polyamide and the hydroxyl group of the cyclic inulooligosaccharide (B) works, and the polyamide has a high viscosity and a melt viscosity. The temperature dependence of is reduced. Further, the retention rate of mechanical strength during recycle molding is also high, and the thermal stability of the polymer is improved.

Therefore, since usual polyamides have a sharp decrease in melt viscosity at a temperature equal to or higher than the melting point, the temperature control range of the molding conditions is narrow during extrusion molding, blow molding and injection molding, and severe molding conditions are required. However, the addition of a small amount of cyclic inulooligosaccharide (B) changes the polymer into a polymer suitable for extrusion molding, blow molding, and injection molding, resulting in a composition with improved moldability and excellent mechanical properties. .

(3) Inorganic Filler (C) As the inorganic filler (C) used in the present invention, various types such as fibrous or fine powder can be used. Specific examples of the fibrous inorganic filler include glass fiber, carbon fiber, potassium titanate fiber, aluminum fiber, stainless steel fiber, brass fiber, aluminum borate fiber and the like. The diameter thereof is in the range of 1 to 20 μm, and the length thereof is in the range of 0.01 to 60 mm, and examples thereof include chopped strands, rovings, milled fibers and powders. Specific examples of the case where the inorganic filler is in the form of fine powder include aluminum hydroxide, magnesium hydroxide, barium sulfate, alumina, zinc oxide, titanium oxide,
Graphite, molybdenum disulfide, carbon black, glass beads, glass powder, milled fiber, hollow glass, zeolite, wollastonite, diatomaceous earth, mica,
Examples thereof include silica, talc, bentonite, montmorillonite, and asbestos. A diameter of 200 μm or less is suitable.

(4) Additional components In the thermoplastic resin composition of the present invention, the physical property balance and surface characteristics of the molded product (surface scratch resistance, gloss, weld appearance, silver streak, flow mark, etc.), molding processability and Various additional components may be added to improve weather resistance and the like. For example, polypropylene, polyethylene (high density, medium density, low density and linear low density) propylene-ethylene block or random copolymers, rubber or latex components such as ethylene copolymer rubber, styrene-butadiene rubber, styrene- Butadiene-styrene block copolymer or hydrogenated product thereof, polybutadiene, polyisobutylene, etc .; thermosetting resin such as epoxy resin, melamine resin, phenol resin, unsaturated polyester resin, etc .; antioxidants (phenolic, sulfur, etc.) ), Lubricants, various organic or inorganic pigments, ultraviolet absorbers, antistatic agents, dispersants, neutralizing agents, foaming agents, plasticizers, copper damage inhibitors, flame retardants, crosslinking agents, flow improvers, etc. is there.

(5) Mixing Ratio of Constituent Components The mixing ratio of each component in the resin composition of the present invention is as follows. The cyclic inulooligosaccharide as the component (B) is 0.01 to 5 parts by weight, preferably 0.02 to 3 parts by weight, and more preferably 0.05 to 2 parts by weight with respect to 100 parts by weight of the thermoplastic resin (A). is there. When the amount of the component (B) is less than 0.01 part by weight, the mechanical strength of the thermoplastic resin (A), particularly when it is recycled, is not sufficiently improved, and when it exceeds 5 parts by weight, the fluidity of the composition decreases. Molding becomes difficult.
Inorganic filler of component (C) is thermoplastic resin (A) 100
0 to 160 parts by weight, preferably 0 to 12 parts by weight
7 parts by weight, more preferably 0 to 108 parts by weight. When the amount of the component (C) exceeds 160 parts by weight, the fluidity of the composition decreases, the moldability deteriorates, and the appearance of the molded product deteriorates. In this case, when the inorganic filler is fibrous, the dispersibility is reduced and the impact strength is significantly reduced. When the inorganic filler is in the form of fine powder, the kneading state in the extruder becomes extremely unstable,
The composition becomes non-uniform.

(6) Manufacturing Method and Molding Method of Composition As a method for obtaining the resin composition of the present invention, various known methods can be used, but the melt kneading method is the most general method. As the melt-kneader, a kneader generally used for thermoplastic resins can be applied. For example, a single-screw or multi-screw kneading extruder can be applied, rolls,
It may be a Banbury mixer or the like. The kneading method is generally a method in which all the components are melt-kneaded at the same time for production, but a mixture of the thermoplastic resin (A) and the inorganic filler (C) is melt-kneaded and pelletized in advance. It is also possible to dry-blend the product with the cyclic inulooligosaccharide (B) and easily mold them by a commonly used molding method, that is, an injection molding method, an extrusion molding method, a hollow molding method, or the like.

[0025]

The present invention will be described below in detail with reference to examples.

The components used in Examples 1 to 11 and Comparative Examples 1 to 11 are as follows. (A) Thermoplastic resin 1) Polyamide 66: Amylan CM300 manufactured by Toray Industries, Inc.
1N 2) Polybutylene terephthalate: manufactured by BASF, Ultradur B4500 3) Styrene-acrylonitrile copolymer: manufactured by Mitsubishi Chemical Co., collimate CLM-GST38 4) Maleic anhydride modified polyolefin: manufactured by Mitsubishi Chemical, modic H100F 5) Vinylsilane-modified polyethylene: Mitsubishi Chemical Co., Ltd., Linkron HF700N (B) Cyclic inulo-oligosaccharide: Mitsubishi Chemical Co., cyclofractane (CFR) (C) Inorganic filler 1) Talc: Fuji Talc Co., MT72) Glass fiber: Asahi Fiber Glass, TMF20
0 (D) Aminosilane: γ-aminopropyltriethoxysilane manufactured by Shin-Etsu Chemical Co., Ltd. Each component shown in Tables 1 to 3 was blended in a compounding composition shown in each table, and a twin-screw kneading extruder (Ikegai Iron Works Co., Ltd. Manufactured by PCM30) under the temperature conditions shown in Table 4 and pelletized.

From the obtained pellets, a screw in-line injection molding machine (manufactured by Arburg, mold clamping pressure: 75 Ton
) Was used to prepare test pieces at the molding temperature shown in Table 4,
The physical properties were evaluated based on the following test methods. The evaluation results are shown in Table 1, Table 2 and Table 3. In addition, Tables 2 and 3 also show the evaluation results of the recycled compositions obtained by re-grinding virgin test pieces. 1) MFR (melt flow rate): JIS K676
0, 2.16kg load. The measurement temperatures are shown in Tables 1 to 3, respectively. 2) Izod impact strength: JIS K7110 (with notch). 3) Flexural strength and flexural modulus: JIS K7203.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

[Table 3]

[0031]

[Table 4]

[0032]

INDUSTRIAL APPLICABILITY The thermoplastic resin composition of the present invention has good mechanical properties, heat resistance and chemical resistance and, at the same time, can be easily subjected to general molding such as blow molding, extrusion molding and injection molding even when it is recycled. In addition, the mechanical properties of the recycled molded product are good.

Claims (1)

[Claims] 1. A thermoplastic resin composition comprising the following components (A), (B) and (C) in the following compounding ratio. (A) 100 parts by weight of thermoplastic resin (B) 0.01 to 5 parts by weight of cyclic inulooligosaccharide represented by the following general formula (I): (In the formula, n represents an integer of 6 to 8) (C) Inorganic filler 0 to 160 parts by weight