JPH0429844A - Laminated sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention comprises a novel laminated sheet, more specifically, a novel laminated sheet consisting of a high molecular weight polycarbonate sheet laminated to a polymer sheet containing a large amount of plasticizer; The present invention relates to a high-quality laminated sheet that does not cause whitening or craze on the polycarbonate sheet.

Conventional technology Aromatic polycarbonate is an engineering plastic with excellent impact resistance, transparency, and dimensional stability.
Polycarbonate sheets are widely used in various fields, and one of their uses is mainly in the glazing field.

However, this aromatic polycarbonate generally has poor solvent resistance, and if it has a molecular weight within a normal range, its use is inevitably limited even when it is formed into a sheet.

On the other hand, in addition to being used alone, polycarbonate sheets can be laminated with other plastic sheets, glass,
In recent years, its use as a laminated sheet made by laminating plywood, metal plates, etc. with an adhesive intermediate film interposed therebetween has been increasing. However, conventional polycarbonate sheets have poor solvent resistance, so if the resin to which they are laminated contains a large amount of plasticizer, the plasticizer may cause deterioration such as cracking or whitening. This has the disadvantage that it cannot be used.

Traditionally, polycarbonate sheets usually have a molecular weight of 30
,000 polycarbonate is used [``Plastics'' Vol. 35, No. 3, No. 14]
Page], such polycarbonate sheets do not have sufficient solvent resistance as described above, and therefore, as a method for improving the stress cracking of unsaturated polyesters caused by styrene solutions, for example, weight average sheets that cannot be processed using an extruder are used. Molecular weight is 70,000-120,000
High molecular weight polycarbonate and normal weight average molecular weight 2
9,000 to 39,000 polycarbonate and molded using an extruder (Japanese Patent Publication No. 61-5786)
Similar to the above, as a method of improving the resistance of casting resins made of unsaturated polyester to styrene solutions, there is a method of modifying polycarbonate by introducing branched chains (Japanese Patent Publication No. 53-28193). Proposed.

However, in the former method, if the blending ratio of high molecular weight polycarbonate is high, the moldability will decrease, and if the blending ratio is low, the effect of improving solvent resistance will be insufficient.
It is difficult to obtain a product with an excellent balance between solvent resistance and moldability. On the other hand, although the latter method of introducing branched chains improves solvent resistance, it has the disadvantage of decreasing impact resistance.

Furthermore, conventionally, the weight average molecular weight is 40.000 to 100.
．． The high molecular weight aromatic polycarbonate having a weight average molecular weight in the range of 30.000 is usually used for extrusion.
Since the melt viscosity is significantly higher than that of aromatic polycarbonate of around 0.000, it was necessary to raise the temperature higher than usual during melt extrusion.

In addition, polycarbonate usually contains chlorine atoms, and these chlorine atoms can degrade the polymer, significantly reduce the molecular weight, or cause discoloration during melt extrusion at high temperatures as described above. This may lead to undesirable situations such as corrosion of the extruder and corrosion of the extruder.

For these reasons, a laminated sheet using polybonate sheets that is resistant to the plasticity contained in the other polymer sheets to be laminated and does not cause whitening or craze when laminated has not been obtained so far. That is the reality.

Problems to be Solved by the Invention Under these circumstances, the present invention consists of a polycarbonate sheet laminated to a polymer sheet containing a plasticizer, and the laminated polycarbonate sheet does not cause whitening or craze. This was done with the aim of providing a laminated sheet that does not cause this problem.

Means for Solving the Problems As a result of intensive research to develop a laminated sheet having the above-mentioned preferable properties, the present inventors have developed a high-molecular-weight aromatic material having a specific molecular weight and containing substantially no chlorine atoms. Group polycarbonate exhibits almost no polymer deterioration or coloring during melt extrusion, and sheets obtained from this polycarbonate have excellent resistance to plasticizers. By laminating this sheet onto a desired plastic sheet, We have found a way to achieve the objective, and based on this knowledge, we have completed the present invention.

That is, in the present invention, (A) the weight average molecular weight is 40.0.
A high molecular weight polycarbonate sheet having a thickness of 0.01 to 15111111 and made of a high molecular weight aromatic polycarbonate which is in the range of 0.00 to 100.000 and does not contain chlorine, (B) polyvinyl chloride, polyvinyl acetate, The present invention provides a laminated sheet with a sheet selected from polyvinyl alcohol, polyvinyl butyral, polyvinyl formal, and cellulose plastic.

The present invention will be explained in detail below.

The polycarbonate sheet used as layer (A) in the laminated sheet of the present invention has a weight average molecular weight of 40.000 to 40.000.
100.000 and is substantially free of chlorine atoms, the high molecular weight aromatic polycarbonate has a structure represented by the general formula % (). ing. In general formula (I), Y is +R or -ArOH, Z is -OH or an aromatic residue, and n is a weight average molecular weight of the polymer of 40,000 to 100.
,000.

When R is an alkyl group, examples of the alkyl group include CH3 CH3Cl(3).

Also, as Ar, example For example CH3 CH3 CH.

Examples include, but Among these, CH.

In the above, those containing 85 mol% or more of the repeating unit represented by the following are preferable.

The weight average molecular weight (Mw) of the polybonate must be in the range of 40,000 to 100,000; if W is less than 40,000, the solvent resistance will be poor, and if it exceeds 100,000, it will melt. It becomes difficult to extrude.Particularly suitable is a material with a value in the range of 50,000 to 80,000.

Furthermore, the polycarbonate must be substantially free of chlorine atoms. Here, "containing substantially no chlorine atoms" means that the chlorine content is below the measurement limit. That is, the chlorine atom content is 0.002% by weight or less as measured by the combustion method, and the Off- content is 0.00002% by weight or less as measured by the silver nitrate titration method.

Such high molecular weight polycarbonate can be prepared by known methods,
For example, it can be produced by the phosgene method or the melting method, but
In the case of the phosgene method, when the polymer has a high molecular weight, the solution viscosity of the polymerization reaction solution increases, making it difficult to remove the polymer from the polymerization solution and purify it.On the other hand, in the case of the melt method, when the polymer has a high molecular weight When the melt viscosity increases, strong stirring is required, and industrially, only those with Mw of about 30,000 can be obtained, which is not suitable.

A preferred method is, for example, the same-phase polymerization method previously discovered by the present inventors; this method produces high-purity, high-molecular-weight polycarbonate that contains virtually no chlorine atoms and no catalyst residue. can be easily manufactured.

On the other hand, as the mating sheet for the layer (B) on which the sheets made of polycarbonate are laminated, a sheet made of polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl formal, or cellulose plastic is used.

The polyvinyl chloride may be a homopolymer obtained by suspension polymerization, emulsion polymerization, solution polymerization, etc. of vinyl chloride monomer, or a copolymer obtained by copolymerizing vinyl chloride monomer with vinyl acetate. It may be present, but the degree of polymerization is 150 to 3,00
A range of 0 is preferred.

As the polyvinyl acetate, those obtained by polymerizing vinyl acetate by emulsion polymerization, solution polymerization, etc. using a polymerization catalyst such as peroxide are used. Polyvinyl alcohol is
It is obtained by saponifying the polyvinyl acetate. Specifically, the polyvinyl acetate is dissolved in a solvent such as alcohol, an alkali catalyst is added thereto, the obtained solid is washed with methanol, etc., and dried. It can be obtained by

This polyvinyl alcohol can be used not only as a completely saponified product but also as one having a degree of saponification of 30% or more.

Polyvinyl butyral is obtained by condensing polyvinyl alcohol and butyraldehyde. Specifically, polyvinyl alcohol and butyraldehyde are condensed using an inorganic acid such as hydrochloric acid or sulfuric acid in an aqueous medium such as water or methanol. Alternatively, it can be produced by simultaneously saponifying polyvinyl acetate and condensing it with an aldehyde.

Further, polyvinyl formal is obtained by condensation of polyvinyl alcohol and formaldehyde, and can be produced in the same manner as the above-mentioned polyvinyl butyral.

On the other hand, cellulose plastics are those obtained by esterifying or etherifying the =11-alcoholic hydroxyl group of plant cellulose, such as cellulose acetate plastic, cellulose acetate butyrate plastic, propionic cellulose plastic, etc. acid cellulose plastic, ethyl cellulose plastic,
Examples include nitrate cellulose plastic.

The cellulose acetate plastic is produced by, for example, acetylating pulp or linter with a mixture of acetic acid and acetic anhydride using sulfuric acid as a catalyst to obtain cellulose triacetate, which is then partially hydrolyzed to form cellulose diacetate for purification. It can be obtained by Those having an acetyl group content of 38 to 40% are preferable for use in plastics.

Acetic butyrate cellulose plastic is esterified using butyric acid and acetic anhydride, and for plastic applications, it is preferable to have a degree of butyroylation of 26 to 39% and a degree of acetylation of 12 to 15%.

Propionate cellulose plastic is made by treating cellulose with a mixture of propionic acid, propionic anhydride, and acetic anhydride.For plastics, the propionyl group content is 3.
Preferably, the acetyl group content is 9 to 47%, and the acetyl group content is 2 to 9%.

Ethyl cellulose plastics are obtained, for example, by treating cellulose with concentrated sodium hydroxide to give an alkaline cellulose, followed by etherification with ethyl chloride or diethyl sulfate. For plastics, the degree of ethylation is 44.5~
48% is preferred.

Nitrate cellulose plastics can also be obtained by direct nitration of purified pulp or linters.

These plastics usually contain plasticizers.

Examples of the plasticizer include heptathalic acids such as dibutyl phthalate, dioctyl phthalate, dioctyl phthalate, diisodecyl phthalate, butyl lauryl phthalate, ditridecyl heptathalate, butylbenzyl hepthaleate, butyl phthalyl butyl glycolate, tributyl citrate, dioctyl Examples include fatty acid types such as adipate, dioctyl azelate, dioctyl sebacate, and methyl acetyl lysyllate, and phosphoric acid types such as tricresyl phosphate and trioctyl phosphate.

Since the high molecular weight polycarbonate sheet used in the present invention exhibits excellent resistance to these plasticizers, whitening and craze do not occur even when laminated.

There are no particular restrictions on the method for producing the laminated sheet of the present invention, and methods commonly used for producing laminated sheets can be used, for example, using a high molecular weight polycarbonate sheet, polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, or polyvinyl formal. Alternatively, a method can be used in which sheets made of cellulose plastic are individually prepared and laminated by heating using a press or roll, or a method in which laminated sheets are simultaneously obtained using a multilayer die.

Next, to explain the production of a polycarbonate sheet by the former method, the high molecular weight aromatic polycarbonate having a My of 40.000 to 100.000 used for the polycarbonate sheet may be one that has been extruded and granulated. However, in order to reduce the thermal history, it is advantageous to directly melt-extrude the polymerization product to form a sheet. According to the solid phase polymerization method previously discovered by the present inventors, polycarbonate in the form of pellets can be directly obtained, and this product is extremely easy to handle when directly sheet extruded, which is preferable.

During extrusion, known stabilizers such as 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-anisole, 2,6-di-tert-butyl-4-ethylphenol, 2.2'-methylenebis(6-tert-butyl-p-cresol'), 2.2'-methylenehis(
4-ethyl-〇-tert-butylphenol), 414'-
Methylenebis(6-tert-butyl-0-cresol), 4
．． 4'-butylidenebis(6-tert-butyl-m-cresol), tetrakis-[methylene-3-(3',5'-
di-tert-butyl-4'-hydroxyphenyl) propionate] methane, 4,4'-thiobis(6-tert-butyl-m-cresol), stearyl-β-(3,5-di-tert-butyl-4-hydroxy phenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3
5-di-tert-butyl-4-hydroxybenzyl)benzene, 1.1.3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, triethylene glycol-bis(3-(3- Tertiary butyl 5-methyl-4
-hydroxyphenyl)propionate], tris(2,4-di-tert-butylphenyl)phosphite, trisnonylphenylphosphite, trisdinonylphenylphosphite, triphenylphosphite, bis(nonyl phenyl) pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite,
Bis(2,6-cy-tert-butyl-4-methylphenyl)
Pentaerythritol diphosphite, diphenicresyl phosphite, diphenylisooctyl phosphite, diphenyldecyl phosphite, diphenyl hydrogen phosphite, bis(nonylphenyl)hydrogen phosphite, bis(2,4-c-tert-butylphenyl) One or two phosphorus antioxidants such as hydrogen phosphite and tetrakis 4,4'-biphenylenediphosphinic acid (2,4-di-tert-butylphenyl).
It is desirable to select and add more than one species and perform melt extrusion.
It is particularly advantageous to add a combination of a phenolic antioxidant and a phosphorus antioxidant.

It is important to mix these stabilizers homogeneously, and it is desirable to mix them using, for example, a Henschel mixer, a Nalter mixer, a tumbler, or the like. Further, these stabilizers may be added directly, or may be diluted with a solvent such as acetone, added to the polycarbonate, and then the solvent may be removed by drying. A high molecular weight polycarbonate sheet is obtained by melt-extruding this mixture using an extruder.

The laminated sheet of the present invention usually has a thickness in the range of 0.15 to 30 mm, and the high molecular weight polycarbonate sheet of layer (A) has a thickness in the range of 0.01 to 15 mm. You can choose the thickness within the range. This polycarbonate sheet not only has excellent resistance to plasticizers, but also has excellent impact resistance and a low degree of coloration.

Furthermore, the molecular weight of the polycarbonate sheet is extremely low during melt extrusion, and therefore, by controlling the molecular weight of the high molecular weight aromatic polycarbonate, a sheet with a desired molecular weight can be easily obtained. In addition, this sheet has less coloration during extrusion, and CI
The b* value measured by the ELAB method is usually 5 or less. The reason why there is little decrease in molecular weight and little coloring is considered to be because chlorine atoms are not substantially destroyed.

Effects of the Invention The laminated sheet of the present invention is a polymer sheet containing a plasticizer laminated with a specific high molecular weight polycarbonate sheet that is resistant to plasticizers, and the polycarbonate sheet does not suffer from whitening or craze. It is a high-quality laminated sheet that does not stain, and has extremely high commercial value.

The laminated sheet of the present invention can be applied to other plastic sheets, plywood,
It is also possible to laminate metal plates, glass plates, etc.

Examples Next, the present invention will be explained in more detail with reference to examples.
The present invention is not limited in any way by these examples.

The molecular weight was measured using gel permeation chromatography (GPC), and the b* value was measured using a color difference meter CR-
200-B (manufactured by Minolta).

Moreover, as an extruder, -shaft 30mm1. L/D=2
4. A T-die type (manufactured by Tanabe Plastics Co., Ltd.) was used.

Example 1 (1) Production of polycarbonate sheet A non-grade polycarbonate sheet containing no chlorine compounds and having a number average molecular weight of 3,900, 46 mol% of terminal hydroxyl groups, and 52 mol% of terminal phenyl carbonate groups was produced from bisphenol A and diphenyl carbonate. Polymer 1
0 kg is passed through a 1 mm diameter die at 240°C and stirred at a high speed of 500 rpm by a knife blade.
It was extruded in a thin strand shape into acetone 12729 at 0°C for 1 hour to effect crystallization and pulverization at the same time.

The resulting slurry of crystalline polycarbonate prepolymer was dried until the acetone content was 35% by weight, and the wet powder was passed through a small extruder (manufactured by Fuji Baudal Co., Ltd., E
XKF-I m pelleter) to produce pellets with a diameter of 2 mm and an average length of 3 mm.
It was dried at 20°C for 2 hours.

The obtained pellets had a number average molecular weight of 3,900, a terminal hydroxyl group of 46 mol %, and a strength of 1.2729/piece.

Next, the pellets were placed in a heated hopper equipped with a nitrogen gas dispersion plate at the bottom, heated to 220°C, and solid phase polymerization was carried out for 12 hours while flowing nitrogen gas at a rate of 3ONm3/hr. went.

The polycarbonate thus obtained has -57
,000 pellets, the chlorine atom content is 0.002% by weight or less, which is below the measurement limit by the combustion method, and the Cl1l- content by AgNO3 titration method is 0.00002% by weight, which is below the measurement limit. It was below.

Next, 90 mg of bis(nonylphenyl)hypyrogen phosphite and 1.0 mg of tris(2,4-di-tert-butylphenyl) phosphite were added to 9 kg of this polycarbonate.
9h was dissolved in acetone and added, followed by stirring and mixing using a Henschel mixer. Note that the mixture almost maintained its pellet shape even after stirring with a Henschel mixer. This mixture was extruded using an extruder at a cylinder temperature of 320°C.
Melt extrusion was performed to create a sheet with a thickness of 500 μm. The Uw of this sheet was 56,000, the molecular weight drop during extrusion was small, no corrosion of the T-die was observed, and the 5-piece value of the 3-thickness sheet was 4.1.

(2) Preparation of laminated sheet (a) Sheet obtained in (1) above and polyvinyl butyral film [S-LEC Film H1, thickness 0.76
mm1 manufactured by Sekisui Chemical Co., Ltd.] were press-bonded at 120° C. to obtain a laminated film. The obtained film was transparent, and no whitening or craze was observed.

(a) The sheet obtained in the above (1) was press-bonded with cellulose acetate film "Acety" (trade name, manufactured by Daicel Chemical Co., Ltd.) at 100°C to obtain a laminated film. The resulting film is transparent, whitening,
No craze was observed.

Example 2 (1) Production of polycarbonate sheet The same procedure as in Example 1 (1) was repeated except that the in-phase polymerization time was changed to 15 hours. A molecular weight polycarbonate was obtained.

The chlorine atom content of this product is less than 2% by weight, which is less than the limit value measured by the combustion method, and CQ- by AgNO3 titration method.
The content was 0.00002% by weight or less, which is below the measurement limit.

Next, 50 mg of diphenyl hydrogen phosphite and stearyl-β-(
3,5-C-11-tributyl-4-hydroxyphenyl)
1.89% of propionate (Irganox 1076, manufactured by Ciba Geigy) was dissolved in acetone and mixed. After stirring and mixing with a Henschel mixer, this mixture was melt-extruded using an extruder in the same manner as in Example 1 (1). A sheet with a thickness of 300 μm was prepared. h of this sheet
is 77.500, and b of the 31II thick sheet
The terminal chain was 4.4.

(2) Preparation of Laminated Sheet The sheet obtained in (1) above and a commercially available polyvinyl chloride sheet were press-bonded at 100°C to obtain a laminated film. The obtained film was transparent, and no whitening or craze was observed.

Example 3 (1) Production of polycarbonate sheet πW44.0 in the same manner as in Example 1 (1) except that the solid phase polymerization time was changed to 10 hours.
00 polycarbonate was obtained. This material contained virtually no chlorine atoms.

Next, to this polycarbonate 9, 135 mg of bis(nonylphenyl) hydrogen phosphite and 4.4
'-biphenylene diphosphinic acid tetrakis (2,4-
Di-tert-butylphenyl) O,h was dissolved in acetone and added, stirred and mixed with a Henschel mixer, and then this mixture was melt-extruded using an extruder in the same manner as in Example 1 (1) to obtain a thick A sheet with a diameter of 1 mm was prepared. The Mw of this sheet is 43,500 and 3mm
The bχ value of the thick sheet was 4.3.

(2) Preparation of laminated sheet The sheet obtained in (1) above and a polyvinyl alcohol sheet were press-bonded at 70°C to obtain a laminated sheet.

No whitening or craze was observed in this sheet.

Comparative Example 1 A commercially available polycarbonate sheet with an Mw of 32,000 and a thickness of 1 mm was press-bonded with a polyvinyl butyral film (formerly S-LEC Film, thickness 76 mm, manufactured by Sekisui Chemical Co., Ltd.) at 120°C. was noticeably whitened.

Comparative Example 2 (1) Manufacture of polycarbonate sheet According to Japanese Patent Application Laid-Open No. 61-238823,
000, the chlorine atom content by combustion method is 0.035% by weight
, CQ'-content by AgNO3 titration method is 0.0015
% by weight of polycarbonate was obtained.

Next, 1.8 g of tris()nylphenyl)phosphite was processed into 972 g of this polycarbonate, and melt extrusion was performed at 320° C. to create a sheet with a thickness of 3 mm. The "W" of this sheet was 39.000, the molecular weight was greatly reduced, and the b* value was 5.1.

(2) Preparation of laminated sheet (a) The sheet obtained in (1) above and a commercially available polyvinyl chloride sheet were press-bonded at 100°C to obtain a laminated film. The obtained sheet showed whitening.

Comparative Example 3 (1) Production of polycarbonate sheet Diphenyl carbonate and bisphenol A were used as a 7mer, and disodium salt of bisphenol A was used to transesterify the sheet. is 0.002% by weight or less, Ag
A polycarbonate having a cp content of 00002% by weight or less as determined by NO3 titration was obtained.

Next, 912 g of this polycarbonate was melt-extruded in the same manner as in Comparative Example 2 to obtain a sheet with a thickness of 3 mm. The h of this sheet is 27,300, and the 5-line value is 5.5
Met.

(2) Preparation of Laminated Sheet A sheet was prepared in the same manner as in Comparative Example 1 using the sheet obtained in (1) above and a polyvinyl butyral sheet. The resulting sheet was significantly whitened.

Claims (1)

[Claims] 1(A) Weight average molecular weight is 40,000 to 100,00
0.01 to 15 m thick made of high molecular weight aromatic polycarbonate that is in the range 0.0 and substantially free of chlorine.
A laminated sheet of a high molecular weight polycarbonate sheet of m and (B) a sheet selected from polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl formal and cellulose plastic.