JPH0813525B2 - Laminated sheet - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention comprises a novel laminated sheet, more particularly a high molecular weight polycarbonate sheet laminated to a polymer sheet containing a large amount of plasticizer, and laminated. The present invention relates to a high-quality laminated sheet that does not cause whitening or craze on a polycarbonate sheet.

BACKGROUND ART Aromatic polycarbonate is widely used in various fields as an engineering plastic excellent in impact resistance, transparency, dimensional stability, etc.
As one of them, a polycarbonate sheet is mainly used in the field of glazing.

However, this aromatic polycarbonate is generally inferior in solvent resistance, and if it has a normal molecular weight range, its use is inevitably restricted even if it is molded into a sheet.

On the other hand, the polycarbonate sheet is used as a laminated seal or the like, which is laminated not only by itself but also with other plastic sheets, or laminated on glass, plywood, metal plate, etc. through an intermediate film for adhesion. The use has increased in recent years. However, since the conventional polycarbonate sheet is poor in solvent resistance, when the resin to be laminated contains a large amount of plasticizer, the plasticizer causes deterioration such as cracking or whitening. Has the drawback that it cannot be used.

Conventionally, a polycarbonate sheet usually has a molecular weight of 3
Although a general polycarbonate of about 0,000 is used ["Plastics", Vol. 35, No. 3, p. 14], such a polycarbonate sheet has insufficient solvent resistance as described above, Therefore, for example, as a method for improving the stress cracking of a styrene solution of unsaturated polyester, a high-molecular weight polycarbonate having a weight average molecular weight of 70,000 to 12,000 that cannot be processed by an extruder and a normal weight average molecular weight of 29,000 to 39,000 polycarbonate. As a method of mixing and molding with an extruder (Japanese Patent Publication No. 61-57860) or a method of improving the resistance of a casting resin composed of an unsaturated polyester to a styrene solution in the same manner as described above, polycarbonate is used as a branched chain resin. A method of denaturation by introduction (Japanese Patent Publication No. 53-28193) is proposed.

However, in the former method, if the blending ratio of the high-molecular weight polycarbonate is high, the moldability decreases,
If the compounding ratio is small, the effect of improving the solvent resistance becomes insufficient, and it is difficult to obtain a product having an excellent balance between solvent resistance and moldability. On the other hand, the latter method of introducing a branched chain has a drawback that impact resistance is lowered although solvent resistance is improved.

Furthermore, conventionally, the high-molecular-weight aromatic polycarbonate having a weight-average molecular weight in the range of 40,000 to 100,000 has a remarkably high melt viscosity as compared with an aromatic polycarbonate having a weight-average molecular weight of about 30,000 which is usually used for extrusion. In the melt extrusion, it was necessary to raise the temperature higher than usual.

In addition, the polycarbonate usually contains chlorine atoms, and these chlorine atoms deteriorate the polymer, significantly reduce the molecular weight, or cause coloring during the melt extrusion at the high temperature as described above. And bring
It causes an unfavorable situation such as corroding the extruder.

Therefore, a laminated sheet using a polycarbonate sheet which has resistance to a plasticizer contained in a polymer sheet to be laminated and does not cause whitening or craze when laminated has not been obtained so far. Is the reality.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention Under the circumstances, the present invention comprises a polymer sheet containing a plasticizer and a polycarbonate sheet laminated, and the laminated polycarbonate sheet has whitening and crazes. The purpose of the invention is to provide a laminated sheet that does not occur.

Means for Solving the Problems As a result of intensive studies to develop a laminated sheet having the above-mentioned preferable properties, the present inventors have found that a high molecular weight aroma having a specific molecular weight and containing substantially no chlorine atom. The group polycarbonate has almost no deterioration or coloring of the polymer during melt extrusion, and the sheet obtained from this polycarbonate has excellent resistance to a plasticizer, and by laminating this sheet on a desired plastic sheet,
It has been found that the object can be achieved, and the present invention has been completed based on this finding.

That is, the present invention provides that (A) the weight average molecular weight is 40,000.
~ 100,000 and a thickness of 0.01 to 15 consisting of a high molecular weight aromatic polycarbonate which is substantially chlorine-free.
The present invention provides a laminated sheet of a high molecular weight polycarbonate sheet having a thickness of mm and a sheet selected from (B) polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl formal, and fiber plastic.

 Hereinafter, the present invention will be described in detail.

The polycarbonate sheet used as the (A) layer in the laminated sheet of the present invention has a weight average molecular weight of 40,000 to 100,
000, and consisting of a high molecular weight aromatic polycarbonate substantially chlorine-free,
The high molecular weight aromatic polycarbonate has the general formula It has a structure represented by. Y in the general formula (I)
Is Or -ArOH, Z is -OH or R is a hydrogen atom or an alkyl group, Ar is an aromatic residue, and n is an integer such that the weight average molecular weight of the polymer is 40,000 to 100,000.

When R is an alkyl group, the alkyl group includes
For example And so on. As Ar, for example, Among these, among these, Is preferred, and particularly in the general formula (I), It is preferable that the content of the repeating unit represented by is 85 mol% or more.

The polycarbonate has a weight average molecular weight (w) of 4
It is necessary to be in the range of 0,000 to 100,000. If this w is less than 40,000, the solvent resistance is poor, and if it exceeds 100,000, melt extrusion becomes difficult. Especially w50,000 ~ 80,000
Those within the range are preferable.

Furthermore, it is necessary that the polycarbonate be substantially free of chlorine atoms. The fact that it contains substantially no chlorine atom means that the chlorine content is below the measurement limit value. That is, the chlorine atom content is 0.002% by weight or less when measured by the combustion method, and C when measured by the silver nitrate titration method.
l ^- content of at most 0.00002% by weight.

Such a high molecular weight polycarbonate can be produced by a known method such as a phosgene method or a melting method. In the case of the phosgene method, when the polymer has a high molecular weight, the solution viscosity of the polymerization reaction solution increases, It is difficult to take it out of the polymerization solution and to purify it. On the other hand, in the case of the melting method, since the melt viscosity increases when the polymer becomes a high molecular weight, strong stirring is required, and w is about 30,000 industrially. It is not suitable because you can only obtain

A preferred method is, for example, the solid-phase polymerization method previously found by the present inventors. According to this method, a high-purity high-molecular-weight polycarbonate containing substantially no chlorine atom and containing no catalyst residue. Can be easily manufactured.

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

The polyvinyl chloride may be a homopolymer obtained by suspension polymerization, emulsion polymerization, solution polymerization or the like of a vinyl chloride monomer, or a copolymer obtained by copolymerization with vinyl acetate or the like. However, those having a polymerization degree in the range of 150 to 3,000 are preferable.

As the polyvinyl acetate, one obtained by polymerizing vinyl acetate by emulsion polymerization or solution polymerization using a polymerization catalyst such as peroxide is used. Polyvinyl alcohol is obtained by saponifying the polyvinyl acetate, and specifically, the polyvinyl acetate is dissolved in a solvent such as alcohol, an alkali catalyst is added thereto, and the obtained solid is treated with methanol or the like. It is obtained by washing and drying. Not only completely saponified polyvinyl alcohol but also those having a saponification degree of 30% or more can be used.

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

In addition, polyvinyl formal is obtained by condensation of polyvinyl alcohol and formaldehyde, and can be manufactured by the same method as the above polyvinyl butyral.

On the other hand, fibrin plastics are those obtained by esterifying or etherifying alcoholic hydroxyl groups of plant fibrin, and examples thereof include acetic acid fibrin plastics, acetyl butyric acid fibrin plastics, and propionic acid fibrinous materials. Examples include plastics, ethyl fiber plastics, nitrate fiber plastics, and the like.

The cellulose acetate plastic is acetylated with a mixture of acetic acid and acetic anhydride using pulp and linter as a catalyst with sulfuric acid to obtain triacetic acid fibrin, which is then partially hydrolyzed into diacetic acid fibrin and purified. It is obtained by
Those having an acetyl group content of 38 to 40% are preferable for use in plastics.

Acrylobutyric acid fibrin plastic is esterified with butyric acid and acetic anhydride, and is preferably used for plastics having a butyroylation degree of 26 to 39% and an acetylation degree of 12 to 15%.

Propionate fibrin plastic is a fiber treated with a mixture of propionic acid, propionic anhydride, and acetic anhydride.
Those having a content of 39 to 47% and an acetyl group content of 2 to 9% are preferable.

Ethyl fibrin plastics are obtained, for example, by treating fibrin with concentrated sodium hydroxide to give alkali fibrin, which is then etherified with ethyl chloride or diethyl sulphate. Ethylation degree of 44.5-48 for plastics
% Is preferable.

Fibrous nitrate plastic is also obtained by direct nitration of refined pulp or linter. These plastics usually contain a plasticizer. Examples of the plasticizer include phthalic acid-based compounds such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, diisodecyl phthalate, butyl lauryl phthalate, ditridecyl phthalate, butyl benzyl phthalate, butyl phthalyl butyl glycolate, tributyl citrate, dioctyl adipate. , Fatty acid-based compounds such as dioctyl azelate, dioctyl sebacate, and methylacetyl ricinoleate, and phosphoric acid-based compounds such as tricresyl phosphate and trioctyl phosphate.

The high-molecular-weight polycarbonate sheet used in the present invention has excellent resistance to these plasticizers, so that whitening or craze does not occur even when laminated.

The method for producing the laminated sheet of the present invention is not particularly limited, and a method conventionally used for producing a laminated sheet, for example, a high molecular weight polycarbonate sheet and polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl formal. Alternatively, it is possible to use a method in which sheets made of fibrin plastic are separately prepared and heated and laminated with a press or roll, or a method in which a laminated sheet is simultaneously obtained by using a multilayer die is used.

Next, the production of the polycarbonate sheet in the former method will be described. As the high molecular weight aromatic polycarbonate having a w of 40,000 to 100,000 used for the polycarbonate sheet, one extruded and granulated may be used, but the heat history In order to reduce the amount, it is advantageous to directly extrude the polymerized product to form a sheet. According to the solid-phase polymerization method that the present inventors have previously found,
Pellets of polycarbonate are directly obtained, which is preferable because it is extremely easy to handle when directly extruding a sheet as it is.

Upon 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'-methylenebis (4-ethyl-
6-tert-butylphenol), 4,4'-methylenebis (6-tert-butyl-o-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-
Hydroxyphenyl) 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-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] and other phenolic antioxidants, tris (2, 4-
Di-tert-butylphenyl) phosphite, trisnonylphenylphosphite, trisdinonylphenylphosphite, triphenylphosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,
4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, diphenicresyl phosphite, diphenylisooctyl phosphite , Diphenyldecylphosphite, diphenylhydrogenphosphite, bis (nonylphenyl) hydrogenphosphite, bis (2,4-di-tert-butylphenyl) hydrogenphosphite, 4,4'-
1 of the phosphorus-based antioxidants such as biphenylenediphosphinic acid tetrakis (2,4-di-tert-butylphenyl)
It is desirable to perform melt extrusion by selecting and adding one or more kinds, and it is particularly advantageous to add a phenol-based antioxidant and a phosphorus-based antioxidant in combination.

It is important to mix these stabilizers homogeneously,
For example, it is desirable to mix using a Henschel mixer, a Nalter mixer, a tumbler, or the like. Further, although these stabilizers may be added directly, they may be diluted with a solvent such as acetone and added to the polycarbonate, and then the solvent may be dried and removed. 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 0.015 to 30 mm, and the (A) layer high molecular weight polycarbonate sheet has a thickness in the range of 0.01 to 15 mm. Can be selected appropriately. This polycarbonate sheet has not only excellent resistance to a plasticizer, but also excellent impact resistance and a small degree of coloring.

Furthermore, the polycarbonate sheet has very little decrease in the molecular weight during melt extrusion, and therefore, by controlling the molecular weight of the high molecular weight aromatic polycarbonate,
A sheet having a desired molecular weight can be easily obtained. Also, this sheet is less colored during extrusion, and a 3 mm thick sheet is
The b ^* value measured by the LAB method is usually 5 or less. As described above, the reason why the decrease in the molecular weight is small and the coloring is small is considered to be that chlorine atoms are not substantially contained.

EFFECT OF THE INVENTION The laminated sheet of the present invention comprises a polymer sheet containing a plasticizer and a specific high molecular weight polycarbonate sheet having resistance to the plasticizer, and the polycarbonate sheet is subject to whitening and crazes. It is a high-quality laminated sheet that never gets used and has an extremely high commercial value.

The laminated sheet of the present invention can be laminated with another plastic sheet, plywood, metal plate, glass plate, or the like.

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

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

The extruder used was a uniaxial 30 mmφ, L / D = 24, T-die type (manufactured by Tanabe Plastic Co., Ltd.).

Example 1 (1) Production of Polycarbonate Sheet Number average molecular weight of 3,900 produced from bisphenol A and diphenyl carbonate, 46 mol% of terminal hydroxyl groups,
240 kg of amorphous polycarbonate prepolymer containing no chlorine compounds with terminal phenyl carbonate groups of 52 mol%
500 rp with a nice blade through a 1 mm diameter die at ℃
1 in 12 kg of acetone at 40 ° C, which is stirred rapidly at m
It was extruded in the form of fine strands over time, and crystallization and pulverization were performed simultaneously.

The obtained crystalline polycarbonate prepolymer slurry was dried until the acetone content became 35% by weight, and the wet powder was mixed with a small extruder (Fuji Paudal Co., Ltd., EX
The pellets were molded with a KF-1 type pelleter) to prepare pellets having a diameter of 2 mm and an average length of 3 mm, and the pellets were dried at 120 ° 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 1.2 kg / piece.

Next, the pellets were placed in a heating hopper provided with a nitrogen gas dispersion plate at the bottom and heated to 220 ° C., and nitrogen gas was mixed with
Solid state polymerization was carried out for 12 hours while flowing at a rate of 0 Nm ³ / hr.

The polycarbonate thus obtained has a w
It is in the form of pellets of 57,000, the chlorine atom content is 0.002% by weight or less below the measurement limit value by the combustion method, and the Cl ^- content by AgNO ₃ titration method is 0.0000% below the measurement limit value.
It was 2% by weight or less.

Next, to 9 kg of this polycarbonate, 90 mg of bis (nonylphenyl) hydrogen phosphite and tris (2,
1.98 g of 4-di-tert-butylphenyl) phosphite was dissolved in acetone and added, and the mixture was stirred with a Henschel mixer. The mixture was kept in a pellet shape even after stirring with a Henschel mixer. This mixture was melt-extruded using an extruder at a cylinder temperature of 320 ° C. to prepare a sheet having a thickness of 500 μm. The w of this sheet was 56,000, the decrease in molecular weight upon extrusion was small, no T-die corrosion was observed, and the b ^* value of the 3 mm thick sheet was 4.1.

(2) Preparation of laminated sheet (a) The sheet obtained in (1) above and a polyvinyl butyral film [S-REC Film HI, thickness 0.76 mm, manufactured by Sekisui Chemical Co., Ltd.] are pressed and pressed at 120 ° C. A laminated film was obtained. The obtained film was transparent and neither whitening nor craze was observed.

(A) The sheet obtained in (1) above and the cellulose acetate film "ACETI" (trade name, manufactured by Daicel Chemical Industries, Ltd.) were pressed under pressure at 100 ° C to obtain a laminated film.
The obtained film was transparent and neither whitening nor craze was observed.

Example 2 (1) Production of Polycarbonate Sheet The procedure of Example 1 (1) was repeated except that the solid phase polymerization time was changed to 15 hours in Example 1 (1).
79,000 high molecular weight polycarbonate was obtained. The chlorine atom content of this product was 0.002% by weight or less, which was below the measurement limit value by the combustion method, and the Cl ^- content by AgNO ₃ titration method was 0.00002% by weight or less, which is below the measurement limit value.

Next, to 9 kg of this polycarbonate, 60 mg of diphenyl hydrogen phosphite and stearyl-β- (3,5
1.8 g of -di-tert-butyl-4-hydroxyphenyl) propionate (Irganox 1076, manufactured by Ciba Geigy) was dissolved in acetone and added, and the mixture was stirred and mixed with a Hensche mixer, and this mixture was treated as in Example 1 (1). Melt extrusion was performed using an extruder to prepare a sheet having a thickness of 300 μm. The w of this sheet was 77,500 and the b ^* value of the 3 mm thick sheet was 4.4.

(2) Preparation of Laminated Sheet The sheet obtained in (1) above and a commercially available polyvinyl chloride sheet were press-pressed at 100 ° C. to obtain a laminated film. The obtained film was transparent and neither whitening nor craze was observed.

Example 3 (1) Production of Polycarbonate Sheet w44,000 polycarbonate was obtained in the same manner as in Example 1 (1) except that the solid phase polymerization time was changed to 10 hours in Example 1 (1). This product contained substantially no chlorine atom.

Next, to 9 kg of this polycarbonate, 135 mg of bis (nonylphenyl) hydrogenphosphite and 0.9 g of tetrakis (2,4-di-tert-butylphenyl) 4,4'-biphenylenediphosphinic acid dissolved in acetone were added, and the mixture was added to a Henschel mixer. After the mixture was agitated and mixed, the mixture was melt-extruded by using an extruder in the same manner as in Example 1 (1) to prepare a sheet having a thickness of 1 mm. The w of this sheet is 43,500, and the b ^* value of a 3 mm thick sheet is 4.3.
Met.

(2) Production of Laminated Sheet The sheet obtained in (1) above and the polyvinyl alcohol sheet were press-pressed at 70 ° C. to obtain a laminated sheet.
No whitening or craze was observed on this sheet.

Comparative Example 1 When a commercially available w sheet having a w of 32,000 and a thickness of 1 mm and a polyvinyl butyral film [S-REC Film HI, thickness 0.76 mm, manufactured by Sekisui Chemical Co., Ltd.] were pressed at 120 ° C., the sheet was remarkably whitened. did.

Comparative Example 2 (1) Production of Polycarbonate Sheet According to Japanese Patent Laid-Open No. 61-238823, a polycarbonate having w of 47,000, a chlorine atom content of 0.035% by weight by a combustion method, and a Cl ^- content of 0.0015% by weight by an AgNO ₃ titration method was used. Obtained.

Next, 1.8 g of tris (nonylphenyl) phosphite was added to 9 kg of this polycarbonate, and melt extrusion was performed at 320 ° C. to prepare a sheet having a thickness of 3 mm. The w of this sheet was 39,000, the decrease in molecular weight was large, and b ^*
The 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-pressed at 100 ° C. to obtain a laminated film. The obtained sheet was whitened.

Comparative Example 3 (1) Manufacture of Polycarbonate Sheet Using diphenyl carbonate and bisphenol A as monomers, a disodium salt of bisphenol A was used, and w was 29,800 and chlorine atom content by the combustion method was 0.002% by weight or less by transesterification reaction. , A polycarbonate with a Cl ^- content of 0.00002% by weight or less was obtained by AgNO ₃ titration method.

Next, 9 kg of this polycarbonate was melt extruded in the same manner as in Comparative Example 2 to obtain a sheet having a thickness of 3 mm. The w of this sheet was 27,300 and the b ^* value was 5.5.

(2) Production of Laminated Sheet A sheet was produced in the same manner as in Comparative Example 1 using the sheet obtained in (1) and the polyvinyl butyral sheet. The obtained sheet was significantly whitened.

Claims (1)

[Claims] 1. A weight average molecular weight of (A) 40,000 to 100,000
And a high molecular weight polycarbonate sheet having a thickness of 0.01 to 15 mm, which is made of a high molecular weight aromatic polycarbonate having substantially no chlorine content, and (B) polyvinyl chloride,
A laminated sheet with a sheet selected from polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl formal, and fiber plastic.