JPS6129874B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention applies vinylidene fluoride resin (hereinafter abbreviated as PVDF) and other thermoplastic resins, particularly vinyl chloride resin (hereinafter abbreviated as PVC), polycarbonate resin (hereinafter abbreviated as PC), acrylonitrile-butadiene- It relates to a laminate with styrene resin (hereinafter abbreviated as ABS) or polyester resin (hereinafter abbreviated as PEs). Although PVDF has excellent physical properties, it has poor adhesion with other thermoplastic resins. However, it is known that it adheres well to polymethyl methacrylate as an exception. However, a laminate having polymethyl methacrylate as an adhesive layer has a drawback of extremely low impact strength. However, in Patent Application No. 161895 filed in 1971, the present applicant used 100 parts by weight of methyl methacrylate polymer (hereinafter abbreviated as PMMA) as a backbone polymer and vinylidene fluoride polymer or fluoride as an adhesive between PVDF and PVC. A graft polymer is proposed in which the graft component is 30 to 500 parts by weight of a copolymer mainly composed of vinylidene chloride. A laminate of PVDF and other thermoplastic resin via this adhesive has better impact strength than the above-mentioned laminate with polymethyl methacrylate as an adhesive layer, but the manufacturing cost is high for industrial use. It has the disadvantage of being expensive. In view of the above-mentioned state of the prior art, the present invention aims to bond PVDF and other thermoplastic resins using an inexpensive adhesive that is practical in terms of cost, and to provide a laminate with excellent impact strength. . The present inventors believe that although PVDF and PMMA are not necessarily compatible with each other depending on their blend ratio, the above-mentioned graft copolymer and PMMA are compatible, and such a composition We focused on the fact that when PVDF and other thermoplastic resins are laminated using an adhesive consisting of The gist of the present invention is as shown in the claims. The present invention will be explained in detail below. In the laminate of the present invention, the adhesive between PVDF and other thermoplastic resin is a composition consisting of a graft copolymer and PMMA. First, for the sake of explanation, the method for producing the graft copolymer will be briefly described. Any known method such as bulk polymerization, emulsion polymerization, suspension polymerization, or electron beam irradiation polymerization may be used. However, from the point of view of graft efficiency,
A suspension polymerization method in which PMMA is suspended in an aqueous medium, a graft component containing an oil-soluble catalyst is added thereto, and graft polymerization is carried out under pressure is desirable, and has excellent impact resistance. Constituting the backbone polymer of such a graft copolymer
PMMA is a methyl methacrylate homopolymer, or a copolymer containing at least 60% by weight of methyl methacrylate and an acrylic ester or methacrylic ester containing an alkyl group having 2 to 5 carbon atoms that can be copolymerized with this. It is a polyblend mainly composed of at least one of these. As this polymer, for example, a slurry obtained by ordinary suspension polymerization may be used as it is, or a coagulated product of an emulsion polymer may be used. The grafting component to be grafted onto PMMA, which is the backbone polymer, is vinylidene fluoride alone, a comonomer containing at least 70% by weight of vinylidene fluoride, or a mixture thereof, and the partner of the comonomer is preferably vinylidene fluoride. One or more of vinyl, propylene hexafluoride, ethylene tetrafluoride, or ethylene trifluorochloride is used. PMMA is the trunk polymer and PVDF is the branch polymer.
The ratio is 30 to 500 parts by weight of PVDF to 100 parts by weight of PMMV.
Parts by weight range. If the amount of PVDF is less than this, it is because the impact strength is low even if the amount of the graft copolymer itself is within the range of the present invention in the adhesive composition.On the other hand, if it is too much, the thermoplastic resin laminated with PVDF This is because they lose compatibility with. In the adhesive for the laminate of the present invention, the graft copolymer is contained in an amount of 5 to 99% by weight, preferably 10 to 60% by weight.
By adjusting PMMA to 1 to 95% by weight, preferably 40 to 90% by weight, a laminate with extremely good adhesion between PVDF and other thermoplastic resins can be obtained.
It exhibits superior impact resistance compared to laminates using only PMMA as an adhesive. In particular, when the branch polymer is present in the adhesive resin composition in an amount of 2 to 60% by weight, more preferably 5 to 50% by weight, even better impact resistance can be obtained. On the other hand, the adhesive is constituted with a graft copolymer.
PMMA is used in the same range as the backbone polymer of the graft copolymer, and may also contain small amounts of additives such as ultraviolet absorbers, pigments, inorganic substances, heat stabilizers, etc. The PVDF to be bonded with the above adhesive resin composition is a vinylidene fluoride homopolymer, a copolymer containing vinylidene fluoride at 50% by mole or more, or a composition containing at least 50% by weight of at least one of these. . Examples of copolymers include vinyl fluoride, 4
A copolymer with ethylene fluoride, propylene hexafluoride, ethylene trifluorochloride, or the like is preferably used. On the other hand, a thermoplastic resin other than PVDF is used as the resin laminated with PVDF through the adhesive composition, and particularly good adhesion can be obtained to PVC, PC, ABS, and PEs. Here, PVC refers to a vinyl chloride homopolymer, a copolymer containing 50 mol% or more of vinyl chloride and a comonomer that can be copolymerized with this, or a composition mainly consisting of at least one of these, and is an impact-strengthening agent. , processing aids, other aids, fillers, and the like. Also
PC is not limited to the known so-called polycarbonate, but also copolycarbonate, a heterobond copolymer having carbonate bonds and other bonds in the main chain,
It also includes modified polycarbonates such as blends mainly composed of these polycarbonates.
In addition, ABS here refers to polybutadiene, a copolymer containing 50 mol% or more of butadiene and a comonomer copolymerizable with it, or a composition mainly composed of at least one of these, and is limited to acrylonitrile. Instead, it is obtained by graft polymerizing a mixture of an olefinic nitrile and a vinyl aromatic hydrocarbon such as styrene or α-methylstyrene. Furthermore, PEs include known thermoplastic polyesters such as polyethylene terephthalate, polybutylene terephthalate, aromatic polyesters, copolymers thereof, and blends containing these homopolymers and copolymers as main components. However, it may also contain processing aids, fillers, pigments, impact strength enhancers, and other additives. The method for manufacturing the laminate of the present invention includes known coextrusion methods such as in-die lamination and outside-die lamination, or a method in which each layer sheet is manufactured separately and laminated in a bonding process. Among these, a preferred method is to extrude each layer of resin separately from an extruder, merge them in a multilayer composite die to create composite flow, extrude from the die lip, and obtain a laminate through a cooling and take-off process. Therefore, the adhesive resin composition is used in the form of a thin film by melting or melting, but when used in the melted state, it is extruded from a nozzle with a diameter of 1 mm and a length of 10 mm under a load of 100 kg/cm ² in a Koka type flow tester.
It is desirable that the melt viscosity at 220° C. is in the range of 1×10 ² to 1×10 ⁶ poise. Among them, 1×10 ³ ~1
It is more desirable that it be within the range of ×10 ⁵ poise.
It is particularly desirable to use a resin having a melt viscosity intermediate between that of PVDF and other thermoplastic resins constituting the adhesive layer. The laminate of the present invention is not limited to a three-layer laminate in which one layer is PVDF, the other layer is a thermoplastic resin layer other than PVDF, and the adhesive composition described above is used as an intermediate layer between these layers; It also includes products in which one or more layers of thermoplastic resin are further laminated on at least one surface layer of the product. Examples and comparative examples will be shown below, but it goes without saying that the present invention is not limited to these examples. The impact strength shown in these examples was measured by the following method. Method for Measuring Impact Strength: The sample is left in dry air at 80°C for 75 hours, and then in ice water at 0°C for 1 hour. Next, the illustrated sample 2 is cut into a 50 mm x 50 mm square and fixed between the upper plate 1 and the lower plate 1' of the sample fixing table of the drop tester shown in longitudinal section in the accompanying drawing. The lower plate 1 is fixed with compressed air from compressor 3.
and fixed upper plate 1 by compression. The pressure of compressed air at this time was 3Kg/cm ² . Next, a heavy peg 4 having a weight of 1 kg and a hemispherical tip with a diameter of 10 mm as shown in the figure is passed through a pulley 6, and a string 5 is pulled up to a height H, and the string 5 is released and allowed to fall. The height H was changed every 10 cm, the test was carried out 10 times for each height, the destruction rate (%) was determined at each height, the destruction rate was blotted on normal probability paper, and from that plot, the failure rate was 50%. The height of the falling plow was determined. Examples 1 to 11 and Comparative Examples 1 to 2 Three extruders were used to extrude under the following conditions, the sheets were introduced into a multi-manifold type T-die, and the three-layer composite sheet was extruded at a die temperature of 200°C. . Conditions of the first extruder: KBO-730A (trade name indicating a grade of vinyl chloride resin manufactured by Kureha Chemical Industry Co., Ltd.)
Extruded at 180℃ using a 90mmφ extruder. Extrusion conditions of the second extruder: KF#1000 (trade name indicating a grade of polyvinylidene fluoride manufactured by Kureha Chemical Industry Co., Ltd.)
A composition in which 100 parts by weight and 15 parts by weight of Tinuvin 328 (trade name indicating a grade of benzotrisol type of ultraviolet absorber manufactured by Ciba Geigy) was added was extruded at 250°C using a 32 mmφ extruder. Extrusion conditions of the third extruder: A graft copolymer containing 57.9 parts by weight of polymethyl methacrylate as a trunk polymer and 42.1 parts by weight of polyvinylidene fluoride as a branch polymer, and polymethyl methacrylate are mixed as shown in Table 1. The pellets were extruded using a 32 mmφ extruder at an extrusion temperature of 245°C, and the pellets were extruded at 200°C using a 25 mmφ extruder. Has a surface temperature of 40℃ after extrusion under the above conditions
Cool it by contacting it with a 300mmφ roll, take it through the roll surface with a surface temperature of 85℃, and roll it to a thickness of 1.
A three-layer composite sheet of mm was obtained. The thickness structure was a vinylidene fluoride layer of 20μ, an adhesive layer of 20μ, and a vinyl chloride resin layer of 960μ. Table 1 shows the results.

【table】

[Table] Example 12 The first extrusion conditions of Example 3 were changed to Panlite F125.
(Product name of polycarbonate manufactured by Teijin)
was extruded at 260°C with a 90mmφ extruder and the die temperature was 250°C, but under the same conditions as Example 3. After heat treatment at 80°C for 75 hours, there was no delamination at all, and the fracture rate was 50%. The height of the plow was 150cm. Comparative Example 3 The test was carried out under the same conditions as in Example 12 except that polymethyl methacrylate was used as the adhesive in Example 12. There was no delamination at all after heat treatment at 80°C for 75 hours, and the fracture rate was reduced by 50%. The height of the peg was 20 cm. Example 13 The first extrusion conditions of Example 6 were JSR-ABS-82 (trade name of acrylonitrile-butadiene-styrene manufactured by Japan Synthetic Rubber Co., Ltd.) was extruded with a 90 mmφ extruder at 220°C, and the second extrusion conditions were Tinuvin. 15 of 328
When the test was carried out under the same conditions as in Example 6 except that the weight part was changed to 10 parts by weight, there was no delamination at all after heat treatment at 80°C for 75 hours, and the drop height at 50% failure rate was
It was 125cm. Comparative Example 4 A test was carried out under the same conditions as in Example 13 except that polymethyl methacrylate was used as the adhesive in Example 13. There was no delamination at all after heat treatment at 80°C for 75 hours, and a 50% reduction in the fracture rate was observed. The height of the peg was 5 cm.

[Brief explanation of the drawing]

The attached figure is a longitudinal cross-sectional view of the drop test machine used for evaluation in the examples of the present invention. 1...Sample fixing table top plate, 2...Sample, 3...
Compressor, 4...heavy plow, 5...string, 6...pulley.

Claims (1)

[Claims] 1. 100 parts by weight of methyl methacrylate polymer as the backbone polymer, 30 to 500 parts by weight of vinylidene fluoride polymer
Graft copolymer containing branch polymer in parts by weight 5 to 99
1. A laminate characterized in that a vinylidene fluoride resin and another thermoplastic resin are bonded together using a resin composition comprising 1 to 95% by weight of a methyl methacrylate polymer as an adhesive. 2. The laminate according to claim 1, wherein the other thermoplastic resin is selected from vinyl chloride resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, or polyester resin. .