OA10662A - Transparent amorphous plate of a crystallizable thermoplastic having a high standard viscosity - Google Patents

Abstract

The invention relates to a transparent, amorphous plate with a thickness in the 1 to 20 mm range, having as its main component a crystallisable thermoplast and in which the crystallisable thermoplast has a standard viscosity SV (DCE) in the 1800 to 6000 range, a process for its production and its use.

Description

The invention relates to an amorphous transparent sheet of a crystallizable thermoplastic having a high standard viscosity, the thickness of which is in the range of 1 to 20 mm. The plate is characterized by very good optical and mechanical characteristics. The invention further relates to a method of preparing this plate and its use.

Amorphous, transparent plates having a thickness of between 1 and 20 mm are well known. These two-dimensional products consist of amorphous, non-crystallizable thermoplastics. Typical examples of such thermoplastics which can be formed into plates are, for example, polyvinyl chloride (PVC), polycarbonate (PC) and poly (methyl methacrylate) (PMMA). These semi-finished products are prepared on so-called extrusion units (see Polymer Werkstoffe, Vol II, Technology 1, page 136, Georg Thieme Verlag, Stuttgart, 1984). The melting of the pulverulent or granulated raw material is carried out in an extruder. The amorphous thermoplastics can be converted afterextrusion because of the viscosity which increases continuously as a function of the decrease in temperature, by using calenders or other finishing tools. Amorphous thermoplastics then have after the transformation a sufficient indishability, that is to say, a high viscosity, to "stand up alone" in the calibration tool. But they are flexible enough to be profiled by the tool. The melting viscosity and the inherent rigidity of the thermoplastic amorphs are so high in the calibration tool that the semi-product does not collapse before cooling in the calibration tool. In the case of easily decomposable materials, such as PVC for example, in the extrusion step 010662 particular processing aids, such as, for example, anti-decomposing stabilizers and lubricants against internal rubbing are required. strong and therefore against an uncontrollable heating. External lubricants are necessary to prevent clinging to walls and cylinders.

In the implementation of PMMA, for example, to eliminate moisture, a degassing extruder is used.

In the preparation of amorphous thermoplastic transparent plates, additives are needed, some of which are expensive, which can migrate in part and cause production problems due to evaporation and superficial deposits on the semi-finished product. The PVC sheets can only be recycled with difficulty or only by means of special processes of neutralization or electrolysis respectively. On the other hand, PC and PMMA plates can only be recycled with difficulty and only at the cost of extreme loss or degradation of the mechanical characteristics. In addition to these disadvantages, the PMMA plates also have extremely low toughness toughness and burst upon breaking or mechanical stressing. In addition, the PMMA plates are easily flammable, so that they can not be used for example for the coating of interior walls and in the construction of exposure halls.

In addition, it is not possible to cold profile PMMA and PC plates. In cold forming, PMMA plates break into dangerous chips. In cold profiling, filiform cracks and white fracture are formed in the PC slabs.

EP-A-0 471 528 discloses a process for forming an object from a poly (ethylene terephthalate) (PET) plate. The intrinsic viscosity of the PET used is in the range of 0.5 to 1.2. Both sides of the PET plate are heat-treated in a tipping tool in a temperature range between the glass transition temperature and the melting temperature. The shaped PET plate is extracted from the mold when the degree of crystallization of the PET profiled plate is within a range of 25% to 50%. The PET plates disclosed by EP-A-0 471 528 have a thickness of 1 to 10 mm. Since the stamped profile, prepared from this plate is partially crystalline, so it is no longer transparent and the surface characteristics of the profile are determined by the stamping process, the temperatures and the molds given in this process, the optical properties ( for example, brightness, lightness and light transmission) of the PET plates used are not essential. In general, the optical properties of these plates are poor and require optimization.

US-A-3,496,143 discloses the deep-vacuum deep drawing of a 3 mm thick PET plate, whose decristallization range must be 5% to 25%. The crystallinity of the pressed profile is greater than 25%. These PET plates also do not fulfill any requirement regarding the optical properties. Since the crystallinity of the plates used is already between 5% and 25%, these plates are cloudy and opaque.

The object of the present invention is to prepare an amorphous plate, transparent, having a thickness of 1 to 20 mm, which has satisfactory mechanical and optical properties.

Good optical properties include, for example, high light transmittance, high surface brightness, extremely low turbidity, and high image clarity.

Good mechanical properties include, among others, high resilience and high tensile strength.

Moreover, the plate according to the invention must be recyclable, more particularly without loss of mechanical characteristics, as well as difficult to ignite, so that it can be used for example for the coating of interior walls and in the construction of exhibition halls.

This problem is solved by means of a transparent, amorphous plate having a thickness in the range of 1 to 20 mm, comprising a crystallizable thermoplastic as a main component, characterized in that the crystallizable thermoplastic has a standard viscosity VS (DCE) of 1 800 to 6000, measured in dichloroacetic acid according to DIN 53728.

The standard viscosity VS (DCE) of the crystallizable thermoplastic, measured in dichloroacetic acid according to DIN 53728, is preferably between 2,000 and 5,000 and particularly preferably between 2,500 and 4,000.

The intrinsic viscosity (IV) (DCE) is calculated from the standard viscosity VS (DCE) as follows: VI (DCE) = 6.67 · 10-4 VS (DCE) + 0.118

The brightness of the surface measured according to DIN 67530 (angle of incidence 20 °) is greater than 120, preferably greater than 130, the light transmission, measured according to ASTM-D 1003, is greater than 84%, preferably greater than 86% and the turbidity of the plate, measured according to ASTM-D 1003, is less than 15%, preferably less than 11%.

The amorphous transparent plate contains a crystallizable thermoplastic as the main component. Crystallizable or partially crystalline thermoplastics are, for example, polyethylene terephthalate, polybutylene terephthalate, cycloolefin polymers and cycloolefin copolymers, preferably polyethylene terephthalate.

Crystallizable thermoplastic is understood to mean, according to the invention, crystallizable homopolymers, crystallizable copolymers, crystallizable compounds, crystallizable recyclables and other crystallizable thermoplastics.

For the purposes of the present invention, amorphous plates are understood to mean such plates which, although the crystallizable thermoplastic used has a crystallinity of between 5% and 65%, are not crystalline. Non-crystalline, i.e. substantially amorphous, means that the degree of crystallinity is generally less than 5%, preferably less than 2% and more particularly 0%. Such an amorphous plate is essentially non-oriented.

Processes for preparing the crystallizable thermoplastics are known to those skilled in the art.

Thus, the poly (ethylene terephthalates) are generally prepared by diffusion polycondensation or by a two-stage polycondensation, the first step up to an average molar mass-corresponding to an IV intrinsic viscosity averaging from about 0.5 to about 0. 7 - being carried out in fusion and the subsequent condensation is implemented by a solid state second condensation. The polycondensation is generally carried out in the presence of known catalysts or catalytic condensation systems. In the solid state condensation, the PET chips are heated under reduced pressure and under an inert degassing atmosphere to a temperature in the range of 180 to 320 ° C, until the desired molar mass is obtained.

The preparation of polyethylene terephthalate is described in detail in a large number of patents, for example JP-A-60-139717, DE-C-2 429 087, DE-A-27 07 491, DE -A-23 19 089, DE-A-16 94 461, JP-63-41 528, JP-62-39 621, DE-A-41 17 825, DE-A-42 26 737, JP-60-141 715, DE-A-27 21 501 and US-A-5 296 586.

Poly (ethylene terephthalates) with particularly high molar masses can be prepared by polycondensation of the acidedicarboxylic-diol precondensates (oligomers) at elevated temperature in a liquid coolant in the presence of customary polycondensation catalysts and optionally co-condensable modifying agents. when the liquid coolant is inert and free of aromatic structural groups and having a boiling point in the range of 200 to 320 ° C, the weight ratio of precondensate dicarboxylic acid-diol (oligomer) to the liquid carrier is in the range of 20:80 at 80:20 and the polycondensation is carried out in the boiling reaction mixture in the presence of a dispersion stabilizer.

In the case of poly (ethylene terephthalate), when measuring the Charpy resilience (measured according to DIN 179 / 1D), there is no breakage of the plate. On the other hand, the akIzod notch resilience (measured according to ISO 180 / 1A) is preferably in the range 2.0 to 8.0 kJ / m2, particularly preferably in the range of 4.0 to 6.0 kJ / m2.

The image sharpness, also referred to as "Clarity" and which is determined at an angle of less than 2.5 ° (ASTM-D 1003), is preferably 96% and particularly preferred, greater than 97%. %. 7 010662

Poly (ethylene terephthalates) with a melting point of crystallites Tm, measured by DSC (Differential Scanning Calorimetry) with a heating rate of 10 ° C / min, 220 ° C to 280 ° C, in particular 220 ° C C at 260 ° C, preferably from 230 ° C to 250 ° C, with a decrystallization temperature range Tc between 75 ° C and 280 ° C, preferably between 75 ° C and 260 ° C, a glass transition temperature Tg between 65 ° C and 90 ° C and a density measured according to DIN 53479 of 1.30 to 1.45 and a crystallinity of between 5% and 65%, represent preferred polymers as starting materials for the preparation of the plate.

The apparent density, measured according to DIN 53466, is preferably between 0.75 kg / dm3 and 1.0 kg / dm3 and particularly preferably between 0.80 kg / dm3 and 0.90 kg / dm3.

The polydispersivity Mw / Mn of the poly (terephthalateethylene) measured by gas chromatography is preferably between 1.5 and 6.0 and particularly preferably between 3.0 and 5.0.

In a preferred embodiment, the plate according to the invention is provided with a UV stabilizeras a photoprotective agent.

The concentration of photoprotective agent is preferably in the range of 0.01 to 5% by weight, based on the weight of the crystallizable thermoplastic.

The light, in particular the ultraviolet component of the sun rays, that is to say in the wavelength range of 280 to 400 nm, induces in the thermoplastics degradation processes, which only cause visual changes in appearance. changes in color, respectively after yellowing, but negatively influence physical and mechanical properties as well. Inhibition of these photochemical degradation processes is of considerable technical and economic importance because otherwise the applicability of many thermoplastics will be extremely limited.

The polyethylene terephthalates begin to absorb UV light, for example already below 360 nm, their absorption increases considerably below 320 nm and is already very pronounced below 300 nm. The maximum absorption is between 280 and 300 nm.

In the presence of oxygen, chain dissociations are mainly observed, but not de-crosslinking. Carbon monoxide, carbon dioxide and carboxylic acids represent photooxidation products whose quantity is preponderant. In addition to the direct photolysis of the ester groups, oxidation reactions which also cause the formation of carbon dioxide via the radical-peroxide have to be taken into account.

Photooxidation of the poly (ethylene terephthalates) can lead to hydroperoxides also by dissociation of hydrogen at the α-position of the ester groups and their degradation products, as well as the chain dissociations associated with this process (H.Day, DM Wiles: J. Appl., Polym., Sci., 16, 1972, page 203).

UV stabilizers, or UV absorbers as photoprotectants, are chemical compounds that can be involved in the physical and chemical processes of light-induced degradation. Carbon black and other pigments may partially act as photoprotective agents. However, these substances are not suitable for the plates because they cause a change in color. For amorphous, transparent plates, only organic and organometallic compounds are suitable which do not cause a change of color or only to a very small extent in the thermoplastic to be stabilized.

Suitable photoprotective agents or UV stabilizers are, for example, 2-hydroxybenzophenones, 2-hydrobenzotriazoles, denickel organic compounds, salicylic acid esters, decinnamate derivatives, resorcinol monobenzoates, desoxanilides, hydroxybenzoates, triazines and desamines. sterically hindered, with 2-hydroxybenzo-triazoles and triazines being preferred.

In a particularly preferred embodiment, the amorphous, transparent plate according to the invention contains as its main component a crystalline poly (ethylene terephthalate) and from 0.01% by weight to 5.0% by weight of 2- (4,6- diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) oxyphenol (structure of Figure la) or from 0.01% by weight to 5.0% by weight of 2,2'-methylenebis (6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol (structure in Figure 1b). In a preferred embodiment, it is also possible to use mixtures of these two UV stabilizers or mixtures of at least one of these two UV stabilizers with other UV stabilizers, the total concentration of photoprotective agents being preferably between 0.01% by weight and 5.0% by weight relative to the weight of poly ( ethylene terephthalate) crystallizable.

Weather tests have shown that even after 5 to 7 years of outdoor use, UV stabilized plates do not show weakening, embrittlement, loss of surface gloss, surface cracking and degradation of mechanical properties.

In addition, against all odds, there is a good aptitude for cold forming without breaking, filiform and / or without white breakage, so that the plates according to the invention can be profiled and folded without the effect of heat. 010662

In addition, the measurements have demonstrated that the PET plate according to the invention ignites only with difficulty and that it is not very combustible, so that it is suitable, for example, for interior wall coatings and in the construction of exposure halls.

In addition, one can recycle without problem the plate conforms to the invention without polluting the environment and without loss of mechanical properties, which makes itparticulièrementappropriate for the uses of courtedurée as billboards or other articles advertisitaires.

In a UV stabilized embodiment, the plate has improved weather resistance and increased UV stability. This means that the plates are not or extremely weakened by weather and sunlight or other UV radiation, so that the panels are suitable for exterior uses and / or critical interior upholstery.

Plates according to the invention, transparent, amorphous, for example, can be prepared by an extrusion process on an extrusion assembly.

Such an extrusion assembly is shown schematically in Figure 2. It essentially comprises a extruder (1) laminator, a flat die (2) as a profiling tool, a finisher / calender (3) as a calibration tool, a cooling bed (4). ) and / or roll conveyor (5) for cooling, a roll draft (6), a cut-off saw (7), a diagonal cutter (9), and possibly a stacking device (8). 11 010662

The process is characterized in that the poly (ethylene terephthalate) is optionally dried, then melted in the extruder, together with the colorant and optionally with the stabilizer W, the melt isprofiled in a die and then caliber in a calender-finisher, it smoothes and cool before sizing the plate.

The method of preparing the plate according to the invention is described in detail on the example of poly (ethylene terephthalate) as thermoplastic.

The poly (ethylene terephthalate) is dried before extrusion, preferably for 4 to 6 days at a temperature of 160 to 180 ° C.

Then, the poly (ethylene terephthalate) is melted in the extruder. Preferably, the temperature of the melt is in the range of 250 to 320 ° C, being able to establish the temperature of the melt substantially by both the temperature of the extruder and the residence time of the material melt in the extruder.

If a photoprotective agent is used, it can be incorporated into the producer of the raw materials or during the preparation of the plate in the extruder.

It is more particularly preferred to add the photoprotective agent using master-mixing technology. To do this, the photoprotective agent is completely dispersed in a solid support material. Some of the resins, such as poly (ethylene terephthalate) or other polymers, which are sufficiently compatible with the crystallizable thermoplastic, are available as a support material.

It is important that the particle size and bulk density of the masterbatch be similar to the particle size and bulk density of the crystallizable thermoplastic, so that a homogeneous distribution and thus even stabilization against UV can occur.

The melt leaves the extruder through a die. This die is preferably a flat die.

The PET melted in the extruder and profiled in the flat thread is calibrated by the rollers of the finisher, i.e., intensely cooled and smoothed. The rolls of the calender can be arranged, for example, in the form of I, F, L or S (Fig. 3).

Then, the material, PET, can be cooled on a roller conveyor, cut on the sides to the dimensions, cut lengthwise and finally stacked. The thickness of the PET plate essentially depends on the drawing device installed at the end of the cooling zone, the cooler cylinders (straighteners) coupled to this device according to the speed and the speed of transport of the extruder both on the one hand and on the other. difference of cylinders on the other hand.

As an extruder, it is possible to use twin or double screw extruders.

The flat die preferably consists of the body of the decomposable tool, the lips and the device for regulating the flow over the width. To do this, the device for the regulation of the flow over the width can be warped by means of clamping screw and pressure. The adjustment of the thickness is done by adjusting the lips. It is important to ensure that the temperature of the PET and the lip is uniform, otherwise the PET melt flows outwardly with a different thickness through the different flow paths. The calibration tool, that is to say, the calender

Finisher, gives the shape and dimensions to the melted PET 13 019662. This is done by freezing below the glass transition temperature by cooling and smoothing. We should no longer be profiled in this state because it would form superficial defects in this cooled state. For this reason, it is preferable to drive the cylinders of the calandria together. The temperature of the lacalander rolls must be lower than the crystalline temperature in order to avoid the adhesion of the molten PET. The melted PET leaves the flat die with a temperature of 240 to 300 ° C.

The temperature of the first cooling cylinder of the calender, in each case according to the production and the thickness of the plate, is between 50 and 80.degree. The second cylinder, a little colder, cools the second or other surface.

In order to obtain a uniform, uniform plate with excellent surface characteristics, it is essential that the temperature of the first cylinder cooler be in the range of 50 to 80 ° C.

While the calibration tool freezes the PET surfaces as directly as possible and cools the profile to such an extent that it becomes undeformable, the cooling system reduces the temperature of the PET plate to substantially room temperature. Cooling can be carried out on a roller conveyor. The speed must be adjusted exactly in relation to the speed of the calender rolls, in order to avoid defects and variations in thickness.

As auxiliary equipment, the extrusion assembly may comprise a cut-off saw for preparing the plates in lengthwise cut, the side cut, the stacking installation and a control station. Lateral cutting or edges is advantageous because the thickness in the edge portion 14 may be sometimes irregular. The control station measures the thickness and optics of the plate.

Thanks to the surprisingly large number of excellent properties, the amorphous and transparent sheet, according to the invention, is perfectly suitable for a large number of different applications, for example for the coating of interior walls, in the construction of exhibition halls and for exhibition articles , for billboards, as screens, in the lighting sector, in the installation of stores and shelves, as advertising articles, as a card holder, as basketball hut panels, as partitions, for desaquariums, as signboards information and materials for prospectuses and newspapers.

In the embodiment stabilized against the UV, the plate according to the invention is also suitable for outdoor applications, such as for example, interiors, roof covers, exterior cladding, covers, applications in the building sector, advertising profiles bright, the cladding of balconies and roof climbs. The invention is explained below with the help of exemplary embodiments without being limited to these examples.

The measurement of the different properties is carried out according to the following standards or methods. Measurement methods

brightness

The gloss of the surface is determined under an angle of 20 ° according to DIN 67530. The lerflet is measured as the optical characteristic of the surface of a plate. Based on ASTM-D 523-78 and ISO2813, the angle of incidence is 20 °. The light ray touches the controlled surface at the angle of incidence established and is reflected or scattered. The light rays are picked up by the photoelectronic receiver and indicated as proportional electrical magnitudes. The measured value is dimensionless and must be indicated in conjunction with the angle of incidence.

Transmission of light:

By transmission of light, we must understand the ratio of the totality of the transmitted light to the quantity of incident light.

The light transmission is measured with a measuring device "Hazegrad plus" according to ASTM-D 1003.

Turbidity and sharpness of image (clarity)

Turbidity is the percentage of light transmitted which deviates by more than 2.5 ° from the incident light beam. Image density is determined at an angle smaller than 2.5 °.

Turbidity and image sharpness are measured using the "Hazegard plus" hiding apparatus according to the ASTM-D 1003 standard.

The surface defects are visually evaluated. Resilience an Charpy:

This quantity is determined according to ISO179 / 1D. Resilience ak Izod:

Notch resilience is measured respectively Izod notch resistance according to ISO 180 / 1A. 16 010662

Density:

The density is determined according to DIN 53479. VS (DCE), VI (DCE):

The standard viscosity SV (DCE) is measured on the basis of DIN 53728 in dichloroacetic acid (DCE).

Intrinsic viscosity is calculated from the standard viscosity as follows VI. (DCE) = 6.67 × 10 -4 VS (DCE) + 0.118

Thermal properties:

The thermal properties, such as the melting point of crystallites Tm, the temperature range of crystallization Tc, the settt-crystallization temperature (of cold crystallization) TCN and the glass transition temperature Tg, differential scanning calorimetry (DSC) are measured. ") with a heating rate of 10 ° C / min.

Molar mass, polydispersivites

The molar masses Mw and Mn and the resulting Mw / Mn polydispersivity are measured by gel permeation chromatography.

Exposure to weather (both sides), UV stability:

The UV stability is checked according to the ISO 4892 test specification as follows:

Test Apparatus: Atlas Ci 65 Weather

Orneter

Test conditions: ISO 4892, artificial weathering data 17 010662: 1000 hours (per side)

: 0.5 W / m2, 340 nm: 63 ° C: 50%: internal and external borosilicate filter: 102 minutes UV light,

Irradiation timeIradiationTemperature

Humidity of airrelativeXenon lamp

Irradiation cycles then 18 minutes UV rays, samples in a water mist and then again 102 minutes UV breaks, etc.

Color change :

The color change of the samples after exposure to artificial weather was measured by a spectrophotometer according to DIN 5033.

It applies: AL: Difference in brightness + AL: the sample is lighter than the standard-AL: the sample is darker than the standard AA: Difference in the field of red-green AA: l sample is more red than standard AA: the sample is less red than standard AB: Difference in the field of blue-yellow + ΔΒ: the sample is yellower than the standard-AB: the sample is more blue than standard ΔΕ: Total color change: ΔΕ = V AL2 + ΔΑ2 + AB2

The larger the standard deviation of the standard, the greater the difference in color. 18 010662

Color difference

The numerical values of <0.3 can be neglected because they do not represent significant color changes.

Yellow index: The yellow index G is the difference from the absence of color towards the "yellow" and is measured according to DIN 6167. Values <5 of the yellow index G are not visible.

In the following examples and comparative examples, each of these is a monolayer plate, transparent, of a different thickness that is after the extrusion assembly described.

Example 1

A transparent poly (ethylene terephthalate) plate having a VS standard viscosity (DCE) of 3490 is prepared which corresponds to an intrinsic viscosity VI (DCE) of 2.45 dl / g. Moisture retardant is <0.2% and the density (DIN5.479) is 1.35 g / cm3. The crystallinity is 19%, the melting point of the crystallites, as measured by DSC being 243 ° C. The decristallization temperature range Tc is between 82 ° C and 243 ° C. The Mw / Mn poly (ethylene terephthalate) dispersivity was 4.3, Mw being 225,070 g / mole and Mn 52,400 g / mole.

The glass transition temperature is 82 ° C.

Before the extrusion, the poly (ethylene terephthalate) is dried for 5 hours at 170 ° C. in a drier and then extruded in a single-screw extruder at an extrusion temperature of 292 ° C. in a flat die on a calender-finisher, of which the cylinders are S-shaped, extruded and smooth to obtain a 3 mm thick plate. The temperature of the first shell of the calender is 73 ° C. and that of each of the other cylinders 67 ° C. The drawing speed and calender rolls are 6.5 m / min. After cooling, the edges of the 3 mm thick transparent PET plate were sawed with the chainsaw, cut in length and stacked.

The prepared transparent PET plate has the following feature profile:

Thickness: 3 mm

Brightness of the surface, face 1: 215 (angle of incidence 20 °), face 2: 214

Transmission of light: 94%

Image clarity: 100%

Turbidity: 0.8% Superficial defects per m2; none (speckles, orange peel, bubbles, etc.): no break: 4.6 kJ / m 2: good, no defects: 0%: 1.33 g / cm 3 in Example 1, use of a Poly (terephthalateles following properties:

Resilience an Charpy Resilience with notchIzod Cold Deformability

CrystallinityMass volume

Example 2

In a similar manner, transparent plate, endethylene, which has VS (DCE) VI (DCE)

DensityCrystallinity: 2717: 1.93 dl / g: 1.38 g / cm3: 44% 010662 - Melting point: 245 ° C crystallites Tm - Mw: 175 640 g / mole - Mn: 49 580 g / mole - Temperature range: from 82 ° t 2 to 245 5C crystallization Tc - Polydispersivity Mw / Mn: 3.54 - Transition temperature: 82 ° C glassy Tg The extrusion temperature is 280 ° C. The temperature of the first cylinder of the calender is 66 ° C and that of the other cylinders 60 ° C. The draft speed and the calender rolls are 2.9 m / min. - Thickness: 6 mm - Surface brightness, face 1: 192 - (angle of incidence 20 °), face 2: 190 - Light transmission: 92.1% - Image clarity: 99, 8% - Turbidity: 2.0% - Superficial defects per m2: none (speckles, orange peel, bubbles, etc.) - Resilience an Charpy: no breakage - Resilience with notch a ^: 4.8 kj / m2 Izod Cold deformability: good, no defects - Crystallinity: 0% - Density: 1.33 g / cm3

Example 3: In a similar manner to Example 2, a transparent plate is prepared. The extrusion temperature is 5 ° C. The temperature of the first cylinder of the lake is 57.degree. C. and that of the other cylinders is 21.degree. C. The extraction speed and that of the cylinders of the lake are 1.7 m / min.

The prepared PET plate has the following characteristics profile:

- Thickness: 10 mm - Surface brightness, face 1: 173 - (angle of incidence 20 °), face 2 171 - Light transmission: 88.5% - Image clarity: 99.4 % - Turbidity: 3.2% Superficial defects per m2: (flecks, orange peel, bubbles, etc.) none - Charpy year-round resilience no breakage - Notch Iz Iz impact strength 5.0 kJ / m2 - Cold deformability : good, no defects of - Crystallinity: 0% Density: Example 4 1.33 g / cm3 In a similar manner to Example 3, a transparent plate is prepared, using a poly (ethylene terephthalate) which has the properties the following: - VS (DCE): 3173 - VI (DCE) 2.23 dl / g - Density: 1.34 g / cm3 - Crystallinity: 12% - Melting point: crystallites Tm 240 ° C - Temperature range of: crystallization Tc from 82 ° C to 240 ° C - polydispersity Mw / Mn: 3.66 - transition temperature: glassy 82 ° C Μ.

Mr 22 010662 204 660 g / mole55 952 g / mole

The temperature of the extruder is 274 ° C. The temperature of the first cylinder of the calender is 50 ° C. and the other cylinders have a temperature of 45 ° C. The speed of the draft and the cylinders of the lake is 1.2 m / min.

Thickness: 15 mm

Surface brightness, face 1: 162 (angle of incidence 20 °), side 2: 159

Light transmission Image clarity Turbidity Superficial defects per m2 (speckles, orange peel, bubbles, etc.) Resilience an Charpy Resilience with notch akIzod Deformability when cold

crystallinity

Density: 89.3%: 98.9%: 5.8%: none: no break: 5.1 kJ / m2: good, no defects: 0%: 1.33 g / cm3

Example 5: In a similar manner to Example 2, a transparent plate is prepared. 70% poly (ethylene terephthalate) of Example 2 is mixed with 30% recycled product of this poly (ethylene terephthalate).

Thickness: 6 mm Surface brightness, face 1: 188 (angle of incidence 20 °), face 2: 186 Light transmission: 92.2 Image clarity: 99.6 23 010662

Turbidity Superficial defects per m2 (speckles, orange peel, bubbles,> etc.): 2.2%: none Resilience an Charpy Resilience with notch akIzod Cold deformability: no rupture: 4.7 kJ / m2: good, no defects

CrystallinityMass volume: 0%: 1.33 g / cm3

Example 6

In a similar manner to Example 1, an amorphous, transparent plate having a thickness of 3 mm was prepared which contained poly (ethylene terephthalate) as the main component according to Example 1 and 1.0% by weight. UV stabilizer, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) oxyphenol (®Tinuvin 1577 from Ciba Geigy Company). Tinuvin 1577 has a melting point of 149 ° C and is heat resistant to about 330 ° C.

Polyethylene terephthalate 0.1% by weight of the UV stabilizer is incorporated directly into the raw material producer. The drying, extrusion and process parameters are selected as in Example 1.

The transparent prepared PET sheet has the following characteristics profile:

Thickness

Surface gloss, face 1 (20 ° angle of incidence), face 2Transmission of light Image clarity (clarity) Turbidity 3 mm 1.0% 208 205 92% 100% 24 010662 - Surface defects per m2 (speckles, orange peel, bubbles, etc.) Resilience an Charpy Resilience with notch akIzod Cold deformability Crystallinity Density: none: no break: 4.6 kJ / m2: good, no defects: 0%: 1.33 g / cm3 After every 1,000 hours of weathering per face in an Atlas Ci 65 Weather Ometer, the PET plate has the following characteristics: - Thickness * 3 mm - Surface gloss, face 1: 202 - (angle of incidence 20 °), side 2: 200 - Light transmission: 91.7% - Image clarity: 100% - Turbidity: 1.2% - Total color change ΔΕ; 0.22 - Dark color change Δε: -0.18 - Red-green color change Δα: -0.08 - Blue-yellow color change Δβ • 0.10 - Superficial defects (cracks, embrittlement): none - Yellow index G: 4 - Resilience Charpy no break - Resilience with notch akIzod: 4, lkJ / m2 Cold deformability good 25 010662

Example 7

In a similar manner to Example 6, an amorphous, transparent plate having a thickness of 3 mm is prepared. The UV stabilizer, 2- (4,6-diphenyl-1,3,5-triazin), is added progressively. 2-yl) -5- (hexyl) oxyphenol (®Tinuvin 1577) as a masterbatch. The masterbatch is composed of 5% by weight of Tinuvin 1577 as the active ingredient component and 95% by weight of the poly (ethylene terephthalate) of Example 1. Before extrusion, 80% by weight of the poly ( ethylene terephthalate) of Example 1 with 20% by weight of the masterbatch, for 5 hours at 170.degree. C. Extrusion and preparation of the analogous plate as in Example 1 were carried out. amorphous, transparent prepared has the following characteristics profile:

Thickness: 3 mm

Brightness of the surface, face 1: 204 (angle of incidence 20 °), face 2: 201

Light transmission Image clarity Turbidity Superficial defects per m2 (speckles, orange peel, bubbles, etc.) Resilience an Charpy Resilience with notch akIzod Deformability when cold

crystallinity

Density: 91.8%: 100%: 0.9%: none: no break: 4.0 kJ / m2: good, no defects: 0%: 1.33 g / cm3

After each 1,000 hours of weather exposure per face in an Atlas Ci '65 Weather Ometer, the following PET plate is present: Characteristics - Thickness 3 mm Surface gloss, face 1: 200 - (angle d 20 ° incidence), side 2: 198 - Light transmission 91.7% - Image clarity (clarity) 100% - Turbidity 1.0% - Total color change ΔΕ: 0.24 - Dark color change Al: -0,19 - Red-green color change Δα: -0,08 - Blue-yellow color change ΔΒ: 0,12 - Superficial defects (cracks, embrittlement): none - Yellow index G: 5 - Resilience year Charpy: no break - Resilience with notch akIzod · '4.0 kJ / m2 Cold deformability. good 5 Example 8:

In a similar manner to Example 2, an amorphous plate, transparent, of a thickness of 6 mm, which comprises as main component, poly (ethylene terephthalate) described in Example 2 and 0.6% 10% by weight of the UV stabilizer, 2,2'-methylene-bis (6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethyl-butyl) phenol (®Tinuvin 360 Ciba-Geigy Company), relative to the weight of the polymer.

Tinuvin 360 has a melting point of 195 ° C and is heat resistant up to about 250 ° C.

As in Example 6, 0.6% by weight of the UV stabilizer in the poly (ethylene terephthalate) is incorporated directly into the producer of the raw materials. 27 010662

The extrusion temperature is 280 ° C. The temperature of the first cylinder of the calender is 66 ° C and that of the other cylinders 60 ° C. The draft range and the calender rolls are 2.9 m / min.

The prepared PET plate, colored transparent, has the following characteristics:

Thickness: 6 mm

Brightness of the surface, face 1: 187 (angle of incidence 20 °), face 2: 185

Light transmission Image clarity Turbidity Superficial defects per m2 (speckles, orange peel, bubbles, etc.) Resilience an Charpy Resilience with notch akIzod Deformability when cold

crystallinity

Density: 91.8%: 99.6%: 2.5%: none: no break: 4.8 kJ / m2: good, no defects: 0%: 1.33 g / cm3 10 After each time 1000 hours of weathering per face in an Atlas Ci 65 Weather Ometer, the PET plate has the following characteristics:

Thickness

Surface brightness, face 1 (20 ° angle of incidence), face 2Transmission of light Image clarity Turbidity

Total color change Δε 6 mm182179 90.9% 99.5% 2.7% 0.56 28 010662

Change of dark color Changevert ΔΑ of color red- Change of color blue-yellow ΔΒ Superficial defects (cracks, embrittlement)

Yellow index G Resilience an Charpy Resilience with notch akIzod Cold deformability AL; -0,21: -0,11: +0,51: none: 6: no break: 4,6 kJ / m2: good, no defects

Example 9: in a similar manner to Example 8, an amorphous, transparent plate is prepared. The extrusion temperature is 275 ° C. The temperature of the first lake cylinder is 57 ° C and the other cylinder 50 ° C. The speed of the draw and that of the cylinders of the lake is 1.7 m / min. The plate is stabilized as described in Example 3. The prepared PET plate has the following characteristic profile:

Thickness 10 mm Surface brightness, face 1 168 (angle of incidence 20 °), face 2 167 Light transmission 88.5% Image clarity (clarity) 99.2% Turbidity 3.95% Surface defects per m2 (speckles, orange peel, bubbles, etc.) none Resilience an year Charpy no break Resilience with notch ak Izod 5.1 kJ / m2 29 010662 Cold deformability

CrystallinityMass volume: good, no defects: 0%: 1,33 g / cm3

After each 1000 hours of weather exposure per face in an Atlas Ci 65 Weather Ometer, the PET plate has the following characteristics:

Thickness: 10 mm Surface brightness, face 1: 164 (20 ° angle of incidence), face 2: 162 Light transmission: 88.2% Image clarity: 99.1% Turbidity: 5, 0% Total color change ΔΕ: 0,47 Dark color change AL: -0,18 Color change red-: -0,09 green ΔΑ Color change blue-: +0,42 yellow ΔΒ Superficial defects per m2: none (cracks, embrittlement) Yellow index G: 5 Resilience an Charpy: no rupture Resilience with notch ak: 4.5 kJ / m2 Izod Cold deformability: good, not defective

Comparative Example 1

In a similar manner to Example 1, a transparent plate is prepared. The poly (ethylene terephthalate) used has a standard viscosity VS (DCE) of 760, which corresponds to an intrinsic viscosity VI (DCE) of 0.62 dl / g. The other characteristics are identical, in the context of the measurement accuracy, to the characteristics of the poly (ethylene terephthalate) of Example 1; The process and temperature parameters are selected as in Example 1. As a result of the low viscosity, a plate can not be prepared. The melt stability is insufficient, so that the melt collapses on the rolls of the shell before cooling.

Comparative Example 2

In a similar manner to Example 2, a transparent plate is prepared, also using the poly (ethylene terephthalate) of Example 2. The temperature of the first cylinder of the calender is 8 ° C. and that of each of the other cylinders is of92 ° C.

The prepared plate is extremely disturbed, light transmittance, image sharpness and brightness are significantly reduced. The plate presents defects and superficial structures. Optical properties are not acceptable for uses requiring transparency.

The prepared plate has the following characteristics profile:

Thickness: 6 mm Surface brightness, face 1: 95 (20 ° angle of incidence), face 2: 93 Light transmission: 74% Image clarity: 90% Turbidity: 52% Superficial defects by m2 (speckles, orange peel, bubbles, etc.): bubbles, orange peel Resilience an Charpy: no break Resilience with notch Izod: 5.0 k J / m2 31 010662 Cold deformability

CrystallinityMass volume: good about 8% 1.34 g / cm3

Claims (26)

32 010662 CLAIMS An amorphous, transparent plate having a thickness in the range of 1 to 20 mm, containing as its main component a crystallizable thermoplastic, characterized in that the crystallizable thermoplastic has a standard viscosity VS (DCE) in the range of 1800 to 6000, measured in acichloroacetic acid according to DIN 53728, with the exception of a plate which contains as a main component a crystallizable thermoplastic having a VS (DCE) standard viscosity of 1800 and a UV stabilizer. 2. Plate according to 1, what the viscosity2,000 to 5,000. 3. Plate according to claim 1, the standard viscosity of 2500 to 4000 is in accordance with claim 1. Plate according to claim 1 to 3, characterized in that the brightness of the surface, measured according to DIN 67530 (angle of incidence 20 ° C) is greater than 120. 5. Plate according to one of the preceding claims, characterized in that the transmission of the lumièrmesurée according to ASTM-D 1003 is greater than 84%. 6. Plate according to at least one of the preceding claims, characterized in that the turbidity, measured according to ASTM-D 1003, is less than 15%. 010662 7. Plate according to one of the preceding claims, characterized in that the crystallizable thermoplastic is taken from poly (ethylene terephthalate) lepoly (butylene terephthalate), a cyclo-olefinic polymer and a cycloolefin copolymer. Plate according to claim 7, characterized in that poly (ethylene terephthalate) is used as the crystallizable thermoplastic. 9. Plate according to claim 8, characterized in that the poly (ethylene terephthalate) contains recycled poly (ethylene terephthalate). 10. Plate according to claim 8 or 9, characterized in that in the measurements of the Charpy resilience, measured according to ISO 179 / 1D, there is no breakage. 11. Plate according to one of claims 8 to 10, characterized in that the impact resilience akIzod, measured according to ISO 180 / 1A, is in the range of 2.0 to 8.0 kJ / m2. 12. Plate according to one of claims 8 to 11, characterized in that the image sharpness, measured according to ASTM-D 1003 at an angle less than 2.5 °, is greater than 96%. 13. Plated according to one of claims 8 to 12, characterized in that the poly (ethylene terephthalate) has a melting point of the crystallites in the range of 220 ° C to 280 ° C, measured by DSC with a speed of reheating of 10 ° C / min. 14. Plate according to one of claims 8 to 13, characterized in that the poly (ethylene terephthalate) has a crystallization temperature in the range of 75 ° C to 280 ° C, measured by DSC with a speed reheating of 10 ° C / min. 15. Plate according to one of claims 8 to 14, characterized in that the poly (ethylene terephthalate) used has a crystallinity in the range of 5 to 65%. 16. Plate according to one of the preceding claims, characterized in that it contains at least one UV stabilizer as a photoprotective agent. 17. Plate according to claim 16, characterized in that the concentration of UV stabilizer is in the range of 0.01 to 5% by weight based on the weight of the crystallizable thermoplastic. 18. Plate according to claim 16 or 17, characterized in that the UV stabilizer is taken from 2-hydroxybenzotriazoles and triazines. 19. Process for the preparation of an amorphous, transparent plate according to one of Claims 1 to 18, characterized in that the crystallizable thermoplastic is melted in the extruder, the melt material is profiled in a die and then calibrated in a stirrer. Finisher with at least two cylinders, slid and cooled, before the plate is sized, the temperature of the first roll of the calender-finisher being in the range of 50 to 80 ° C. 20. The method of claim 19, wherein the crystallizable thermoplastic is melted together with the UV stabilizer in the extruder. 55 010662 21. Plate according to one of claims 19 or 20, characterized in that the crystallasis thermoplastic is dried before melting in the extruder. 22. Method according to one of claims 19 to 21, characterized in that the crystallizable thermoplastic is poly (ethylene terephthalate) (PET). 23. The method of claim 22, wherein the polyethylene terephthalate is dried prior to extrusion for 4 to 6 hours at a temperature of 160 to 180 ° C. 24. The method of claim 22 or 23, characterized in that the temperature of the molten PET is in the range of 250 to 320 ° C. 25. Method according to one of claims 20 to 24, characterized in that the addition of the UV stabilizer is effected by masterbatch technology. 26. Use of the transparent amorphous plate according to one of claims 1 to 18 in the exterior and interior applications.