JP2002086635A - Method for manufacturing styrenic resin laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing a styrenic resin laminate enhanced in toughness while holding various properties of an SPS/ GPPS laminate. SOLUTION: The styrenic resin laminate is manufactured by co-extruding a styrenic polymer with a mol. weight of 150,000-350,000 having a syndiotactic structure or a composition (A) containing this polymer and a styrenic polymer with a mol.wt. of 220,000 or more having an atactic structure, or a composition (B) containing this polymer, in a molten state at 250-300 deg.C. The co-extrudate is heat treated at 160 deg.C or less to manufacture the styrene resin laminate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a styrenic resin laminate, and
The present invention relates to a method for producing a styrene-based resin laminate useful as various industrial films, bags and containers, such as stationery, packaging films and containers for daily necessities, release films, adhesive tapes, capacitors, and dielectrics.

[0002]

2. Description of the Related Art Stretched films of a styrene-based polymer having a syndiotactic structure (hereinafter sometimes abbreviated as "SPS") have been known for their heat resistance, chemical resistance, rigidity, transparency, easy cut, Because of its excellent properties such as foldability, moisture resistance, and mold release properties, various proposals have been made on its production method, film properties, and uses. In addition, styrene polymers having an atactic structure (hereinafter referred to as GP)
It may be abbreviated as PS. ) Films are excellent in rigidity, thermoformability and heat seal adhesion, and are used for various applications. Moreover, the stretched film is excellent in transparency. Further, a laminated film in which another styrene-based polymer is laminated has been proposed for the purpose of improving thermoformability and heat sealability and reducing costs while maintaining the characteristics of the SPS stretched film. Further, in the case of an SPS single layer stretched film, the heat treatment was conventionally performed at a temperature (200 ° C.) as close to the melting point as possible in order to improve heat resistance.
Moreover, the stretched film of the GPPS single layer is 100 to 120.
After stretching at 0 ° C, no heat treatment is performed. On the other hand, SPS / GP
In the case of a multilayer stretched film such as a PS / SPS configuration, S
When heat-treated at the same temperature as the PS monolayer stretched film, G
There is a problem that the mechanical properties are deteriorated because the orientation relaxation of the PPS layer is large.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and provides a method for producing a styrene-based resin laminate having improved toughness while maintaining various properties of the SPS / GPPS laminate. The purpose is to do.

[0004]

Means for Solving the Problems As a result of extensive studies, the present inventors have found that SPS having a specific molecular weight range or a composition containing SPS and GPPS or GPP having a specific molecular weight range.
The composition containing S is melt co-extruded, and after co-stretching,
It has been found that the above-mentioned object can be achieved by performing a heat treatment at a temperature of not more than ° C, and the present invention has been completed. That is, the present invention relates to a styrene polymer having a syndiotactic structure having a molecular weight of 150,000 to 350,000 or a composition (A) containing the polymer, and a molecular weight of 220,000.
The styrene-based polymer having the atactic structure or the composition (B) containing the polymer is melt co-extruded at 250 to 300 ° C., co-stretched, and then heat-treated at a temperature of 160 ° C. or less. It is intended to provide a method for producing a styrene-based resin laminate.

[0005]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a styrene polymer having a syndiotactic structure (SPS) or an SPS-containing composition (A) is used. The syndiotactic structure in SPS refers to a syndiotactic structure, in which a phenyl group which is a side chain to a main chain formed from carbon-carbon bonds is alternately located in the opposite direction. And its tacticity is quantified by nuclear magnetic resonance ( ^13C -NMR) using isotope carbon. ^The tacticity measured by the ¹³ C-NMR method is determined by the ratio of the presence of a plurality of continuous structural units, for example, 2
Can be indicated by a diad, three can be indicated by a triad, and five can be indicated by a pentad. The SPS referred to in the present invention is usually 75% by racemic diad.
Polystyrene, poly (alkylstyrene), poly (halogenated styrene), poly (halogenated alkylstyrene) having a syndiotacticity of 85% or more, preferably 30% or more, preferably 50% or more in racemic pentad ), Poly (alkoxystyrene), poly (vinyl benzoate), hydrogenated polymers thereof, mixtures thereof, or copolymers containing these as main components. Here, poly (alkylstyrene) includes poly (methylstyrene), poly (ethylstyrene), poly (isopropyl styrene), poly (tertiary butylstyrene), poly (phenylstyrene), poly (vinylnaphthalene) , Poly (vinylstyrene) and the like, and poly (halogenated styrene) includes poly (chlorostyrene), poly (bromostyrene), poly (fluorostyrene) and the like. Examples of poly (halogenated alkylstyrene) include poly (chloromethylstyrene), and examples of poly (alkoxystyrene) include poly (methoxystyrene) and poly (ethoxystyrene).

[0006] Of these, particularly preferred styrene-based polymers include polystyrene, poly (p-methylstyrene), poly (m-methylstyrene), poly (ethylstyrene), poly (divinylbenzene), and poly (p-methylstyrene). Tertiary butyl styrene), poly (p-chlorostyrene), poly (m-chlorostyrene), poly (p-fluorostyrene), hydrogenated polystyrene and copolymers containing these structural units.

Such SPS is prepared, for example, using a titanium compound and a condensation product of water and a trialkylaluminum as a catalyst in an inert hydrocarbon solvent or in the absence of a solvent. (A monomer corresponding to the union) can be produced (JP-A-62-187708). For poly (halogenated alkylstyrene), see JP-A-1-46.
No. 912, these hydrogenated polymers are disclosed in
It can be obtained by the method described in JP-A-8505.

The comonomer in the styrenic copolymer includes, in addition to the above-mentioned styrenic polymer monomers, olefin monomers such as ethylene, propylene, butene, hexene and octene; diene monomers such as butadiene and isoprene; Examples include diene monomers and polar vinyl monomers such as methyl methacrylate, maleic anhydride, and acrylonitrile. In particular, a styrene polymer having a styrene repeating unit content of 80 to 100 mol% and a p-methylstyrene repeating unit content of 0 to 20 mol% is preferably used.

In the present invention, it is necessary that the weight average molecular weight of SPS is not less than 150,000 and not more than 300,000. Here, the weight average molecular weight is 150,000.
If it is less than 3, the mechanical properties decrease, and if it exceeds 300,000, uneven layer ratio distribution occurs in the width direction. Further, regarding the molecular weight distribution, the width is not limited, and various types can be applied. The SPS used in the present invention is:
The degree of crystallinity needs to be 20% or more, preferably 25% or more, and more preferably 30% or more. Here, if the crystallinity is less than 20%, heat resistance and oil resistance may not be sufficient.

In the present invention, the composition (A) containing SPS is preferably a composition in which GPPS is added to SPS at a ratio of 2 to 50% by weight. GP added to SPS
PS means industrially bulk polymerization, solution polymerization, suspension polymerization,
It is a styrenic polymer obtained by radical polymerization by a method such as emulsion polymerization. The polystyrene obtained by such radical polymerization usually has an atactic structure and does not have stereoregularity. In addition, polystyrene having an atactic structure referred to herein is a polymer composed of one or more aromatic vinyl compounds or a copolymer of one or more other vinyl monomers copolymerizable with one or more aromatic vinyl compounds. It may be a polymer, a hydrogenated polymer of these polymers, or a mixture thereof.

Here, the aromatic vinyl compound includes styrene, α-methylstyrene, methylstyrene, ethylstyrene, isopropylstyrene, tertiary butylstyrene, phenylstyrene, vinylstyrene, chlorostyrene, bromostyrene, fluorostyrene, chloromethyl. There are styrene, methoxystyrene, ethoxystyrene and the like, and these are used alone or in combination of two or more. Among them, preferred aromatic vinyl compounds include styrene, p-methylstyrene, m-methylstyrene, ethylstyrene and p-tert-butylstyrene.

Other copolymerizable vinyl monomers include:
Vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, methyl acrylate, ethyl acrylate,
Alkyl acrylates such as propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, benzyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, Amyl methacrylate, hexyl methacrylate,
Methacrylic acid alkyl esters such as octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate and benzyl methacrylate, maleimide, N-methylmaleimide, N-ethylmaleimide, N-butylmaleimide, N
Maleimide compounds such as -laurylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide and N- (p-bromophenyl) maleimide.

As the GPPS, those having a weight average molecular weight of 220,000 or more are used. Here, when the weight average molecular weight is less than 220,000, uneven layer ratio distribution occurs in the width direction during coextrusion.

The SPS or the SPS-containing composition (A) used in the present invention contains the SPS within a range not to impair the object of the present invention.
A thermoplastic resin other than S and GPPS, a thermoplastic elastomer, a compatibilizer, and the like can be blended. These compounds are contained in the A layer in an amount of 0 to 30% by weight, and more preferably 0 to 20% by weight.
% By weight, particularly in the range of 0 to 10% by weight.
Further, various additives may be blended as necessary. Hereinafter, these compounding agents and additives will be described.

(1-1) Thermoplastic resins other than SPS and GPPS The thermoplastic resins other than SPS and GPPS which may be used in the present invention include linear high-density polyethylene, linear low-density polyethylene, and high-pressure method. Low density polyethylene, isotactic polypropylene, syndiotactic polypropylene, block polypropylene, random polypropylene, polybutene, 1,2-polybutadiene, poly4
-Methylpentene, cyclic polyolefin and polyolefin resins represented by copolymers thereof, isotactic polystyrene, HIPS, ABS, AS, styrene-methacrylic acid copolymer, styrene-methacrylic acid alkyl ester copolymer, styrene -Glycidyl methacrylate copolymer, styrene-acrylic acid copolymer, styrene-alkyl acrylate copolymer,
Polystyrene resin represented by styrene-maleic acid copolymer, styrene-fumaric acid copolymer, polyester resin such as polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyamide 6, polyamide 6,6 Any known material such as polyamide resin, polyphenylene ether, and PPS can be arbitrarily selected and used. These thermoplastic resins can be used alone or in combination of two or more.

(1-2) Thermoplastic Elastomer Specific examples of the thermoplastic elastomer that may be used in the present invention include, for example, natural rubber, polybutadiene, polyisoprene, polyisobutylene, neoprene (registered trademark),
Polysulfide rubber, thiocol rubber, acrylic rubber,
Urethane rubber, silicone rubber, epichlorohydrin rubber, styrene-butadiene block copolymer (SB
R), hydrogenated styrene-butadiene block copolymer (SEB), styrene-butadiene-styrene block copolymer (SBS), hydrogenated styrene-butadiene-
Styrene block copolymer (SEBS), styrene-isoprene block copolymer (SIR), hydrogenated styrene-isoprene block copolymer (SEP), styrene-isoprene-styrene block copolymer (SIS),
Styrene rubber such as hydrogenated styrene-isoprene-styrene block copolymer (SEPS), and olefin rubber such as ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), and linear low density polyethylene elastomer Or butadiene-acrylonitrile-styrene-core-shell rubber (AB
S), methyl methacrylate-butadiene-styrene-
Core shell rubber (MBS), methyl methacrylate-butyl acrylate-styrene-core shell rubber (MA
S), octyl acrylate-butadiene-styrene-
Core shell rubber (MABS), alkyl acrylate-
Core-shell type particle-like elastic materials such as butadiene-acrylonitrile-styrene-core-shell rubber (ABS), butadiene-styrene-core-shell rubber (SBR), and siloxane-containing core-shell rubber such as methyl methacrylate-butyl acrylate-siloxane; Modified rubber and the like can be mentioned. These can be used alone or in combination of two or more.

(1-3) Compatibilizer The compatibilizer that may be used in the present invention is, for example, a copolymer having a styrene structure, and the styrene structure in the molecule is 40 mol% or more, preferably 50 mol% or more. A polymer containing at least mol% is exemplified. Specific examples of such a compatibilizer include, for example, a styrene-butadiene block copolymer (S
BR), hydrogenated styrene-butadiene block copolymer (SEB), styrene-butadiene-styrene block copolymer (SBS), hydrogenated styrene-butadiene-styrene block copolymer (SEBS), styrene
Isoprene block copolymer (SIR), hydrogenated styrene-isoprene block copolymer (SEP), styrene-isoprene-styrene block copolymer (SI
S), hydrogenated styrene-isoprene-styrene block copolymer (SEPS). These are all polymers containing a styrene structure in an amount of 50 mol% or more.

(1-4) Various additives Anti-blocking agent (AB agent) Examples of the anti-blocking agent include the following inorganic particles or organic particles. As the inorganic particles, IA
, IIA, IVA, VIA, VIIA, VI
Oxides, hydroxides, sulfides, nitrides, halides, carbonates, sulfates, acetates, phosphates, phosphites, organic carboxyls of Group II, IB, IIB, IIIB and IVB elements Acid salts, silicates, titanates, borates and their hydrated compounds, composite compounds centered on them, and natural mineral particles.

Specifically, Group IA element compounds such as lithium fluoride, borax (sodium borate hydrate), magnesium carbonate, magnesium phosphate, magnesium oxide (magnesia), magnesium chloride, magnesium acetate, magnesium fluoride, titanium Magnesium silicate, magnesium silicate, magnesium silicate hydrate (talc), calcium carbonate, calcium phosphate, calcium phosphite, calcium sulfate (gypsum), calcium acetate, calcium terephthalate, calcium hydroxide, calcium silicate, calcium fluoride, titanate Group IIA element compounds such as calcium, strontium titanate, barium carbonate, barium phosphate, barium sulfate, barium sulfite, titanium dioxide (titania), titanium monoxide, titanium nitride, zirconium dioxide (zirconia), monoxide Group IVA element compounds such as ruconium, group VIA element compounds such as molybdenum dioxide, molybdenum trioxide, and molybdenum sulfide; group VIA element compounds such as manganese chloride and manganese acetate; group VIII element compounds such as cobalt chloride and cobalt acetate; Group IB element compounds such as cuprous copper; Group IIB element compounds such as zinc oxide and zinc acetate; IIIB such as aluminum oxide (alumina), aluminum hydroxide, aluminum fluoride, and aluminosilicate (alumina silicate, kaolin, kaolinite) Group compound, silicon oxide (silica, silica gel), graphite,
Examples include IVB group element compounds such as carbon, graphite, and glass, and particles of natural minerals such as kernalite, kainite, mica (mica, kinunmo), and virose ore.
Here, the average particle size of the inorganic particles used is 0.1 to 10 μm
Are preferred.

Examples of the organic particles include Teflon (registered trademark), a melamine resin, a styrene-divinylbenzene copolymer, an acrylic resin, a silicone resin, and a crosslinked product thereof. The above-mentioned inorganic or organic AB agent can be used alone or in combination of two or more.

Antioxidant The antioxidant can be arbitrarily selected from phosphorus, phenol, sulfur, and other known agents. In addition, these antioxidants may be used alone, or
Two or more can be used in combination. Further, 2- [1-hydroxy-3,5-di-t-pentylphenyl) ethyl] -4,6-di-t-pentylphenyl acrylate, pentaerythrityl-tetrakis [3
-(3,5-di-t-butyl-4-hydroxyphenyl) propionate] and the like are also preferably used.

Nucleating Agents As nucleating agents, metal salts of carboxylic acids such as aluminum di (pt-butylbenzoate) and phosphorus such as sodium methylenebis (2,4-di-t-butylphenol) acid phosphate Metal salts of acids,
Any known compounds such as talc and phthalocyanine derivatives can be arbitrarily used. In addition, these nucleating agents can be used alone or in combination of two or more.

Plasticizer Any known plasticizer such as polyethylene glycol, polyamide oligomer, ethylene bisstearamide, phthalic ester, polystyrene oligomer, polyethylene wax, or silicone oil can be used as the plasticizer. These plasticizers can be used alone or in combination of two or more. Release Agent The release agent can be arbitrarily selected from known materials such as polyethylene wax, silicone oil, long-chain carboxylic acid, and long-chain carboxylic acid metal salt. These release agents may be used alone or in combination of two or more.

Process Oil In the present invention, in order to improve the elongation, the oil is further added at 40 ° C.
It is preferable to blend a process oil having a kinematic viscosity of 15 to 600 mm ² / s. Process oils are roughly classified into paraffinic oils, naphthenic oils, and aroma oils depending on the type of oil. Among them, all carbons related to paraffins (straight chains) calculated by the ndM method are included. Paraffinic oils with a percentage to number of 60% Cp or more are preferred. The viscosity of the process oil is 40
The kinematic viscosity at 15 ° C. is preferably from 15 to 600 mm ² / s.
5~500mm ² / s is more preferable. If the kinematic viscosity of the process oil is less than 15 mm ² / s, it has an effect of improving elongation, but it has a low boiling point and may cause melt-kneading with SPS and white smoke, gas burning, and roll adhesion during molding. If the kinematic viscosity exceeds 600 mm ² / s, burning of white smoke gas and the like is suppressed, but the effect of improving elongation is poor. These process oils can be used alone or in combination of two or more.

The amounts of the various additives mentioned above may be added to the SPS-containing composition as required, preferably in the range of 0 to 3% by weight, more preferably in the range of 0 to 1.5% by weight. In addition, the above various additives can be added by preparing a master batch using the polymer to be used.

In the present invention, GPPS or G
The PPS-containing composition (B) is used. GPP used here
S may be the same as that used in the composition (A). However, it is preferred that the ratio of SPS weight average molecular weight / GPPS weight average molecular weight be in the range of 0.3 to 0.9. Outside this range, the dispersion of SPS becomes poor. Further, as the GPPS-containing composition (B), GP
A composition in which SPS is added to PS at a ratio of 5 to 50% by weight is preferable. If the SPS is less than 5% by weight, the effect of the addition is hardly obtained. That is, if it exceeds 50% by weight,
Regardless of whether the heat treatment temperature is 160 ° C. or lower or 160 ° C. or higher, there is no difference in mechanical properties, and the effects of the present invention cannot be obtained.

In the present invention, the GPPS or the GPPS-containing composition (B) may contain other thermoplastic resins, thermoplastic elastomers, compatibilizing agents, and other additives as long as the object of the present invention is not impaired. Various additives may be blended accordingly. For these specific examples, those described for the SPS-containing composition can be used. The same applies to the mixing ratio. In addition, GPPS or GPP
The S-containing composition (B) contains 70% of the styrene-based polymer component.
Or more, preferably 80% or more, more preferably 90%
It is preferable to include the above.

In the present invention, the styrene resin laminate is prepared by mixing the above-mentioned SPS or the SPS-containing composition (A) and GPPS or the GPPS-containing composition (B) with 250 to 3 parts.
It is manufactured by melt co-extrusion at 00 ° C., co-stretching, and heat-treating at a temperature of 160 ° C. or less. The co-extrusion method is
Although there is no particular limitation, any of a feed block method and a multi-manifold method may be used, and a die such as a coat hanger die, a T-die, and a ring die can be used. After the melt co-extrusion, by cooling and co-stretching, the crystallinity of the SPS can be improved and transparency can be exhibited. As a method of co-stretching, for example, uniaxial stretching,
Simultaneous biaxial stretching, sequential biaxial stretching, and a multi-stage stretching method combining these can be used. Among them, in the present invention, it is preferable to use a simultaneous or sequential biaxial stretching method. In this case, the area stretching ratio is preferably 3 to 20 times, more preferably 5 to 10 times. This co-stretching temperature is
90-200 ° C is preferable, and 90-150 ° C is more preferable.

Further, in the method of the present invention, after co-stretching, heat treatment is performed at a temperature of 160 ° C. or less. This heat treatment is preferably performed at 150 ° C. or lower, particularly preferably 100 to 100 ° C.
It may be performed in a temperature range of 130 ° C., preferably for 1 to 300 seconds, more preferably for 1 to 60 seconds. According to the above method, a multilayer film having excellent interlayer adhesion and higher transparency can be produced without using an adhesive. In addition, as a method other than the above-mentioned method, a single film may be prepared and laminated using an adhesive.

In the styrene resin laminate produced by the method of the present invention, the layer composed of SPS or the SPS-containing composition (A) is a layer A, the GPPS or the GPPS-containing composition (B).
When the layer consisting of is represented as layer B, it is composed of layer A and layer B, and the number and arrangement of the layers are not particularly limited, but are composed of three layers of layer A / layer B / layer A. Are preferred. In this case, the two A layers present on both sides of the B layer may have the same composition and properties, but may have different compositions and properties within the above range. The ratio of the layer thickness of the layer A / layer B / layer A is 1/18/1 to 1/18/1.
The ratio is preferably 2/1/2, more preferably 1/18/1 to 3/2/3, particularly preferably 1/18/1 to 1/1/1. Here, if the layer A is too thin, a problem tends to occur in the mechanical strength of the laminate, and if the layer A is too thick, a problem tends to occur in the heat workability of the laminate. The thickness of the A layer is 1 to 50.
0 μm, further 1 to 400 μm, especially 1 to 300 μm
Is preferred. If the A layer is less than 1 μm, a problem is likely to occur in the mechanical strength of the laminate, and if it is 500 μm or more, a problem is likely to occur in the thermal workability of the laminate.

The total haze of the laminated film comprising layer A / layer B / layer A of the present invention is 10% or less, preferably 8% or less, more preferably 6% or less. All haze is 10
%, The transparency and transparency of the film are not sufficient, and the object of the present invention cannot be achieved. The total haze of the laminated film can be reduced to 10% or less by appropriately adjusting the composition of each layer, the thickness ratio of each layer, and the laminating conditions, stretching conditions, heat treatment conditions, and the like.

[0032]

EXAMPLES Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. The SP used in the examples and comparative examples
S and GPPS are as follows.

SPS SPS1: Syndiotactic polystyrene copolymer (manufactured by Idemitsu Petrochemical Co.) Comonomer: paramethylstyrene, copolymerization ratio: 12 mol%, weight average molecular weight: 230,000 SPS2: syndiotactic polystyrene polymer (Idemitsu Petroleum) Weight average molecular weight 220,000 GPPS GPPS1: atactic polystyrene (trade name: HH32, manufactured by Idemitsu Petrochemical Co., Ltd.), weight average molecular weight 340,000

Additives (Masterbatch for adding antioxidant and antiblocking agent) For copolymers, antiblocking agent aluminosilicate (Shilton AMT08, manufactured by Mizusawa Chemical) is added to SPS1
Was mixed with 10,000 ppm powder, melt-extruded at 300 ° C., and then pelletized. For homo SPS, the same amount of aluminosilicate as for the above copolymer is used for SPS2, and the antioxidant pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (Product name: IRGANOX, manufactured by Ciba Specialty Chemical Co., Ltd.)
1010) was mixed with 10,000 ppm powder, and after melt extrusion, pelletized. -For the middle layer GPPS, an antioxidant IR is added to GPPS1.
GANOX1010 and Sumilizer GS (Sumitomo Chemical)
Were each mixed with 10,000 ppm powder and pelletized.

Example 1 SPS1 and GP prepared by dry blending a masterbatch
PS1 was heated at 270 ° C. with each 50 mmφ single screw extruder.
And a feed block set at 270 ° C., 50
Co-extrusion through a 0 mm wide coat hanger die, 85
It cooled with the cooling roll of ° C, and obtained the 250-micrometer multilayer unstretched sheet of SPS / GPPS / SPS. This sheet has a layer ratio of SPS / GPPS / by setting the discharge ratio of each extruder.
SPS: 2/6/2. This unstretched sheet is continuously stretched 3.3 times at 105 ° C. in the machine direction, then 3.8 times at 115 ° C. in the transverse direction, and then stretched 1 time in the width direction at 120 ° C.
Heat treatment for 10 seconds while relaxing 0%, about 10μm
Was obtained.

Example 2 A three-layer stretched film was obtained in the same manner as in Example 1 except that the heat treatment temperature was changed to 140 ° C. Example 3 A three-layer stretched film was obtained in the same manner as in Example 1, except that the heat treatment temperature was changed to 160 ° C.

Example 4 A three-layer stretched film was obtained in the same manner as in Example 3, except that the intermediate layer was composed of a dry blend of SPS1 / GPPS 1: 20/80% by weight. Example 5 A three-layer stretched film having a layer ratio of 1/8/1 was obtained in the same manner as in Example 3. Example 6 A three-layer stretched film was obtained in the same manner as in Example 3, except that the SPS layer was composed of SPS2.

Comparative Example 1 A three-layer stretched film was obtained in the same manner as in Example 1 except that the heat treatment temperature was changed to 200 ° C. Comparative Example 2 A three-layer stretched film was obtained in the same manner as in Comparative Example 1, except that the intermediate layer was composed of a dry blend of SPS1 / GPPS1: 80/20% by weight. Comparative Example 3 A three-layer stretched film was obtained in the same manner as in Comparative Example 1, except that the SPS was changed to SPS2 and the heat treatment temperature was set to 220 ° C.

Comparative Example 4 SPS1 and GP prepared by dry blending a masterbatch
PS1 dry blended at 20/80% by weight, 50m
Extruded at 270 ° C. using a mφ single screw extruder, extruded through a feed block set at 270 ° C., a coat hanger die having a width of 500 mm, cooled with a cooling roll at 85 ° C.
A 0 μm monolayer unstretched sheet was obtained. This unstretched sheet is continuously stretched 2.7 times at 105 ° C. in the longitudinal direction, then stretched 3.0 times at 115 ° C. in the transverse direction, and then relaxed 10% in the width direction at 120 ° C. for 10 seconds. Heat treatment, about 20
A μm stretched film was obtained.

The film impact strength of each of the films produced in the above Examples and Comparative Examples was measured by the following method. The results are shown in Table 1. Evaluation of Film Impact Strength A film was punched out from below with a pendulum having a head diameter of 1 inch, and a film impact tester (a pendulum type) manufactured by Toyo Seiki Seisaku-sho, Ltd. was used to measure the impact head at 1 inch.

[0041]

[Table 1]

[0042]

According to the present invention, various films such as heat resistance, chemical resistance, rigidity, transparency, easy cut, dead fold, moisture resistance, mold release, thermoformability, heat seal adhesion, etc. In addition to its excellent properties, it can efficiently produce a styrene-based resin laminate with excellent toughness, and can be used for packaging films and containers for foods, drugs, stationery, daily necessities, release films, adhesive tapes, capacitors, and dielectrics. Thus, a styrene resin laminate useful as various industrial films, bags and containers can be provided at low cost.

Continued on front page F-term (reference) 4F100 AK12A AK12B AL05A AL05B BA02 BA16 DA01 EH202 EJ372 EJ422 GB15 GB16 GB23 GB66 JA07A JA07B JA11A JA11B JA12A JA12B JB01 JJ03 JK01 JK20 JL01 JL12 JN01 YY00XX03 BC03 BC03 BC06X BC07W BC07X BC08W BC08X BC11W BC11X BC12W BC12X FD020 FD070 FD200 GF00 GG01 GG02 GQ00

Claims (4)

[Claims] 1. A styrene polymer having a molecular weight of 150,000 to 350,000 having a syndiotactic structure or a composition (A) containing this polymer, and a molecular weight of 220,000.
The styrene-based polymer having the atactic structure or the composition (B) containing the polymer is melt co-extruded at 250 to 300 ° C., co-stretched, and then heat-treated at a temperature of 160 ° C. or less. A method for producing a styrene resin laminate. 2. The styrene according to claim 1, wherein the composition (A) is obtained by adding a styrene polymer having an atactic structure to a styrene polymer having a syndiotactic structure in a proportion of 2 to 50% by weight. A method for producing a base resin laminate. 3. The styrene according to claim 1, wherein the composition (B) is obtained by adding a syndiotactic styrene polymer to an atactic styrene polymer in a proportion of 5 to 50% by weight. A method for producing a base resin laminate. 4. A composition comprising a syndiotactic styrene polymer and an atactic styrene polymer in a proportion of 2 to 50% by weight as the composition (A).
As the composition (B), a syndiotactic styrene polymer was added to an atactic styrene polymer.
The method for producing a styrenic resin laminate according to claim 1, wherein the styrenic resin laminate is used in an amount of from 50 to 50% by weight.