JPH0526816B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a soft vinyl chloride resin composition, and more particularly, the present invention relates to a soft vinyl chloride resin composition, and more specifically, it is made by blending a plasticizer with a copolymer of vinyl chloride and a monovalent or divalent metal salt of an α,β-unsaturated dicarboxylic acid monoester. The present invention relates to a soft vinyl chloride resin composition. Vinyl chloride resin is a typical plastic that is inexpensive among synthetic resins, has well-balanced physical properties, and has a wide range of uses, from hard to soft. In particular, soft vinyl chloride resin molded products with a rubber-like feel, which are obtained by adding a large amount of plasticizer to vinyl chloride resin, have lower cost, moldability, and lower moldability than vulcanized rubber.
It has excellent weather resistance, colorability, etc., and is widely used. However, since it is inferior to vulcanized rubber in terms of creep properties at high temperatures, attempts have been made to improve the creep properties by using vinyl chloride resins with a high degree of polymerization or those containing gel. However, even with these methods, 100
Because there is a limit to the ability to improve creep characteristics at temperatures above 100°C, its use in fields that may be exposed to temperatures above 100°C is currently restricted. In view of the current situation, the present inventor has conducted various studies to improve the high-temperature creep properties by modifying vinyl chloride resin, adding new functions, etc. , 0.2 to 30% by weight of monovalent or divalent metal salts of β-unsaturated dicarboxylic acid monoesters and 0 to 20% of other vinyl compounds.
100 parts by weight of copolymer consisting of 20 parts by weight of plasticizer
By using a soft vinyl chloride resin composition characterized by containing ~300 parts by weight, the inventors have found that the creep characteristics at high temperatures are significantly improved, and have completed the present invention. The copolymer in the present invention is obtained according to a normal vinyl chloride resin manufacturing method such as suspension polymerization or emulsion polymerization, and its constituent components α, β-
Examples of monovalent or divalent metal salts of unsaturated dicarboxylic acid monoesters include alkyl monoesters such as methyl, ethyl, propyl, butyl, and octyl esters such as maleic acid, fumaric acid, itaconic acid, and citraconic acid; epoxy; Monoesters of the above acids containing hydroxy, halogen, ether, vinyl groups, etc. and Li ⁺ , Na ⁺ , Cs ⁺ , Mg ⁺⁺ ,
Examples include salts of monovalent or divalent metals such as Ca ⁺⁺ , Ba ⁺⁺ , Zn ⁺⁺ , and Cd ⁺⁺ . These metal salts of α,β-unsaturated dicarboxylic acid monoesters may be used alone or in combination of two or more. If a metal salt of an α,β-unsaturated dicarboxylic acid is used instead of this metal salt, not only will it be difficult to form a copolymer with vinyl chloride, but the resulting copolymer will also be difficult to form. However, the high temperature creep characteristics cannot be sufficiently improved. Furthermore, other vinyl compounds include ethylene,
Common examples include propylene, vinyl acetate, vinylidene chloride, vinyl ether, acrylic ester, and methacrylic ester. As the plasticizer, plasticizers commonly used for soft vinyl chloride resins can be used, such as di-2-ethylhexyl phthalate, di-n-
Octyl phthalate, diisodecyl phthalate,
Phthalic acid esters such as dibutyl phthalate and dihexyl phthalate; Linear dibasic acid esters such as dioctyl adipate and dioctyl sebacate; Trimellitic acid esters and polyester polymer plasticizers; Epoxidized soybean oil, epoxidized linseed oil, etc. Plasticizer: Phosphate ester plasticizers such as triphenyl phosphate and tricresyl phosphate can be used alone or in combination of two or more. The proportion of the monovalent or divalent metal salt of the α,β-unsaturated dicarboxylic acid monoester in the copolymer of the present invention is 0.2 to 30% by weight, preferably 0.5 to 15% by weight. If the proportion of this metal salt is less than 0.2% by weight, sufficient effect on high-temperature creep properties will not be exhibited, and if it exceeds 30% by weight, not only will the properties of the vinyl chloride resin be impaired, but such copolymer Combining has many manufacturing restrictions. The amount of plasticizer used in the present invention is appropriately selected depending on the hardness of the target product, but when considering soft rubber-like products, the amount of plasticizer used in the present invention is 20 to 300 parts by weight per 100 parts by weight of the vinyl chloride copolymer in the present invention. parts by weight, preferably 30 to 200 parts by weight. If it is less than 20 parts by weight, a soft and rubber-like product cannot be obtained, and if it exceeds 300 parts by weight, it is difficult to sufficiently improve creep characteristics at high temperatures. The vinyl chloride resin composition of the present invention is similar to general vinyl chloride resins, including stabilizers, lubricants, fillers, antioxidants, ultraviolet absorbers, processing aids, blowing agents, pigments,
Various additives such as flame retardants and impact resistance aids can be contained as necessary. It may also contain other polymers. An ionically crosslinked molded article can be obtained by molding this composition by a conventional vinyl chloride resin processing method such as extrusion molding, compression molding, calendar molding, blow molding, or injection molding. This product has extremely excellent heat resistance and elasticity, so it can be used in automobile window sealing materials, electric wire sheathing materials, etc. that require these characteristics.
It can be suitably used in fields such as packing. Hereinafter, the present invention will be explained in more detail with reference to Examples. In addition, the parts shown in the examples are parts by weight unless otherwise specified. Example 1 10 In an autoclave, 250 parts of deionized water and partially saponified polyvinyl alcohol (degree of saponification 70%,
Average degree of polymerization 500) 0.2 parts, di-2-ethylhexyl peroxydicarbonate 0.17 parts, and the comonomers shown in Table 1 were charged and degassed, then vinyl chloride was charged and the temperature was raised to 40°C with stirring. , the polymerization reaction was carried out for 20 hours. After the polymerization was completed, the contents were taken out and dehydrated and dried to obtain a vinyl chloride copolymer having the composition shown in Table 1. Next, using the obtained vinyl chloride copolymer, roll kneading was performed at 150°C for 5 minutes with the composition shown in Table 2.
Got a sheet. This sheet was heated and pressed at 160° C. for 10 minutes to produce a pressed sheet of a predetermined thickness. Using this press sheet, high-temperature creep characteristics at temperatures of 100°C or higher were evaluated by heating deformation tests and rebound resilience. The heat deformation test was conducted according to JIS K-6723, and the deformation rate (%) was expressed after 1 hour after the load was applied at a load of 1 kgf and a measurement temperature of 120°C. In addition, the impact resilience was expressed as impact resilience modulus (%) at 140°C using a Danlopt tripsomer in accordance with BS903, Part A8: 1963. The results are shown in Table 1.

【table】

[Table] Example 2 Same as Example 1 except that a composition consisting of 100 parts of vinyl chloride/magnesium monomethyl maleate (90/10) copolymer resin, the plasticizer shown in Table 3, and 4 parts of dibutyltin maleate was used. A similar experiment was conducted. The results are shown in Table 3.

【table】

【table】

Claims (1)

[Claims] 1 100% by weight of a copolymer consisting of 70 to 99.8% by weight of vinyl chloride, 0.2 to 30% by weight of a monovalent or divalent metal salt of an α,β-unsaturated dicarboxylic acid monoester, and 0 to 20% by weight of another vinyl compound per part, plasticizer
A soft vinyl chloride resin composition comprising 20 to 300 parts by weight.