JPS648664B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a vinyl chloride resin composition that has excellent heat deformation resistance and solder resistance properties and can be easily molded into thin walls without crosslinking. In recent years, various electric/electronic devices, automobiles, etc. have become smaller and lighter, and as a result, there has been a strong demand for thinner electric wires, tubes, films, etc. used. Conventionally, in order to compensate for the deterioration in heat deformation resistance and solder resistance due to thinning, products have been put on the market in which vinyl chloride resin compositions are chemically crosslinked by radiation crosslinking or by a crosslinking agent. However, cross-linking methods using radiation irradiation require large-scale equipment investment such as industrial electron beam irradiation equipment, and have the disadvantage of high irradiation costs, while chemical cross-linking methods using cross-linking agents requires careful temperature control during molding to prevent premature crosslinking inside the molding machine, and it is also necessary to heat or otherwise crosslink the molded product after molding, which slows down the manufacturing process. The disadvantage is that it becomes complicated. The inventors of the present invention conducted intensive studies to eliminate these drawbacks, and as a result, they decided to add a maleic acid polyester to a polyvinyl chloride resin consisting of a polyvinyl chloride gel component that is insoluble in tetrahydrofuran and a tetrahydrofuran soluble component. It was discovered that only by doing so could the intended purpose be achieved, leading to the present invention. The purpose of the present invention is to achieve heat deformation resistance equivalent to that of radiation crosslinking or chemical crosslinking using a crosslinking agent at low cost by simply performing ordinary molding processing without performing crosslinking treatment.
The object of the present invention is to provide a vinyl chloride resin composition that has solder resistance and can be processed into thin-walled molding. That is, a polyvinyl chloride resin consisting of 5 to 90% by weight of polyvinyl chloride gel insoluble in tetrahydrofuran and the remainder soluble in tetrahydrofuran.
For 100 parts by weight, a polyester composition in which part or all of the raw dibasic acid is maleic acid,
This is a vinyl chloride resin composition characterized in that it contains 0.1 to 20 parts by weight. As used herein, the term "gel fraction insoluble in tetrahydrofuran" refers to the extraction residue extracted with hot tetrahydrofuran for 22 hours using a Soxhlet extractor and separated using a 350 mesh filter. The vinyl chloride resin containing a polyvinyl chloride gel component that is insoluble in tetrahydrofuran used in the present invention is mainly composed of vinyl chloride or vinyl chloride, as described in JP-A-54-80354. A mixture with a polymerizable monomer is mixed with at least one copolymerizable polyfunctional monomer having two or more ethylenic double bonds in the molecule in an amount of 0.01 to 10% by weight based on the vinyl chloride monomer. Insoluble in tetrahydrofuran, obtained by carrying out the polymerization in the presence of polymers at temperatures ranging from 0 to 50 °C until at least 60% by weight of the total monomers in the system have been polymerized. It is characterized by having a gel content of 5 to 90% by weight and the remainder consisting of a tetrahydrofuran soluble component, and contains the following copolymers. That is, examples of monomers copolymerizable with vinyl chloride include fatty acid vinyl esters, vinylidene halides, acrylic acid alkyl esters, methacrylic acid alkyl esters, acrylonitrile, alkyl vinyl ethers, styrene, and derivatives thereof. Polyvinyl chloride resins outside the scope of the present invention, i.e., those that are insoluble in tetrahydrofuran and have a gel content of less than 5% by weight, or general polyvinyl chloride resins that do not contain a gel content, are used as long as they do not impair the gist of the present invention. Although it may be used in a blend with the polyvinyl chloride resin used in the present invention, when used alone, the heat deformation resistance and solder resistance properties were not satisfied. If the gel content exceeds 90% by weight and is insoluble in tetrahydrofuran, the heat deformation resistance will be improved, but the composition will not come together well when kneaded, and this will cause problems in processing, so it is not preferable. Next, one of the features of the present invention is that the appearance of the molded article is improved by adding a polyester in which part or all of the dibasic acid as a raw material is maleic acid. The raw dibasic acid is maleic acid alone or a combination of maleic acid and other dibasic acids, and specific examples include adipic acid, azelaic acid, sebacic acid, and phthalic acid. Examples of glycols that are one of the raw materials include ethylene glycol, 1,
2-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol TMPD (2,2,6-trimethyl-
1,3-pentanediol) and the like. The maleic acid-based polyester used in the present invention is obtained by appropriately combining the dibasic acid and glycol described above, and further reacting them with a medium or higher alcohol or fatty acid, which is generally called a chain stopper. The amount of maleic acid polyester added is preferably 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, per 100 parts by weight of the polyvinyl chloride resin used in the present invention. Increasing the amount of maleic polyester added increases the gelation promoting effect and contributes to improving the appearance of the molded product, but adding 20 parts by weight is sufficient, and adding more than that is meaningless. ,
If it is less than 0.1 part by weight, no gelation promoting effect can be expected. The resin composition of the present invention may contain stabilizers, fillers, lubricants, modifiers, colorants, etc., which are usually added to vinyl chloride resin compositions, as necessary, and the amount used may be Not particularly limited. Furthermore, as for the plasticizer used in combination with the maleic acid polyester, a plasticizer that is commonly added to vinyl chloride resin compositions can be used, and the amount used is not particularly limited, but from the purpose of the present invention, It is desirable that the total amount of plasticizer is 25 to 70% by weight. The present invention will be specifically explained below with reference to Examples and comparisons. In addition, the unit of the compounding agent was expressed as parts by weight. Examples 1 to 5 and Comparative Examples 1 to 3 The compositions of Examples 1 to 5 and Comparative Examples 1 to 3 shown in Table 1 were extruded onto a conductor (unplated copper single wire) with a diameter of 0.5 mm, and the coating thickness was 0.25 mm. electric wire was created.

[Table] *1 Manufactured by Dainippon Ink & Chemicals Co., Ltd. Composition whose main component is maleic acid polyester Its properties are shown in Table 2.

[Table] The degree of shape retention was visually observed.
Example 6 and Comparative Examples 4 and 5 The compositions of Example 6 and Comparative Examples 4 and 5 shown in Table 3 were extruded to form tubes with an outer diameter of 15 mm and a wall thickness of 0.3 mm.

【table】 Its characteristics are shown in Table 4.

[Table] Example 7 and Comparative Example 6 The compositions of Example 7 and Comparative Example 6 shown in Table 5 were extrusion molded to produce films with a thickness of 0.3 mm.

【table】

【table】 Its characteristics are shown in Table 6.

[Table] As described above, the vinyl chloride resin composition according to the present invention exhibits good molding processability, as well as excellent heat deformation resistance and solder resistance, and also has the advantage of not requiring crosslinking treatment. When considered together, the industrial value is extremely large.

Claims (1)

[Claims] 1 Polyester in which part or all of the dibasic acid as a raw material is maleic acid, based on 100 parts by weight of a polyvinyl chloride resin consisting of 5 to 90% by weight of polyvinyl chloride gel insoluble in tetrahydrofuran and the remainder soluble in tetrahydrofuran. A vinyl chloride resin composition characterized by adding 0.1 to 20 parts by weight of.