JPH0239043B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a matte vinyl electric wire with excellent heat deformation resistance. (A) Electric wires coated with a soft vinyl chloride resin composition, which is generally made by adding a plasticizer to a vinyl chloride resin and has a soft rubber-like feel, are widely used in place of rubber. Electric wires coated with conventional vinyl chloride resin compositions are easier to manufacture than rubber wires, can be colored freely, and have self-extinguishing properties, but because they use vinyl chloride resin, which is a thermoplastic resin. It is inferior in terms of heat deformation resistance, solder heat resistance, heat deformation rate (JIS K 6723, the following measurements also follow), compression set rate (JIS K 6723, the following measurements also follow),
K.6301 (the following measurements also follow) were worse than rubber-coated wires. Furthermore, depending on the application, there are many fields in which the unique luster of vinyl chloride resin is disliked. Regarding these problems,
A fully satisfactory solution could not be obtained with electric wires using conventional vinyl chloride resin compositions. That is, in order to improve the heat deformation resistance using the conventional method, after coating the electric wire with a vinyl chloride resin composition, the heat deformation resistance can be improved by crosslinking treatment such as electron beam irradiation or peroxide crosslinking. was once. However, these methods have drawbacks such as expensive equipment and expensive formulations. Furthermore, in order to eliminate the gloss of vinyl chloride resin, it is necessary to lower the extrusion temperature, which tends to result in poor productivity and generally poor physical properties. In addition, regarding improvements in creep resistance, shape retention at high temperatures, permanent elongation, rebound resilience, etc. of vinyl chloride resin compositions,
The resin composition in No. 80354, i.e. polyvinyl chloride gel insoluble in tetrahydrofuran 5
With a composition consisting of 100 parts by weight of a vinyl chloride resin with ~90 parts by weight and the remainder soluble in tetrahydrofuran, and 25 to 200 parts by weight of a plasticizer,
It was found that better creep resistance and shape retention at high temperatures can be obtained compared to general vinyl chloride resin compositions. However, the compression set (JIS K-6301, 70℃×
22hrs, 25% compression, below this condition) is about 45~50
% and that of general soft vinyl chloride resin compositions
Although the creep resistance was good compared to 55% to 80%, the creep resistance was poor compared to 20% to 40% of general vulcanized rubber. In view of these circumstances, the present inventors conducted intensive studies and found that a nitrile with a gel content that is insoluble in methyl ethyl ketone (hereinafter abbreviated as MEK) is based on the resin composition disclosed in JP-A No. 54-80354. By mixing an appropriate amount of rubber (hereinafter abbreviated as NBR), it has excellent creep resistance, soldering heat resistance, shape retention at high temperatures, permanent elongation, heat deformation resistance such as heat deformation rate, excellent matting effect, and workability. They discovered the surprising fact that a high-quality vinyl electric wire could be produced and completed the present invention. An object of the present invention is to provide an electric wire coated with a vinyl chloride resin composition that has excellent heat deformation resistance such as solder heat resistance, heat deformation rate, and compression set, and has good processability and an excellent matting effect. be. That is, the present invention comprises 100 parts by weight of a vinyl chloride resin consisting of 5 to 90% by weight of polyvinyl chloride gel insoluble in tetrahydrofuran and the remainder soluble in tetrahydrofuran, and NBR insoluble in MEK.
10-400 parts by weight of NBR, consisting of 20-95% gel content and the balance soluble in MEK, and 25-300 parts plasticizer.
It is characterized by being coated with a vinyl chloride resin composition that has excellent heat deformation resistance such as solder heat resistance, heat deformation rate, and compression set rate, and has good workability and a good matte effect, mainly consisting of parts by weight. The present invention provides a heat-resistant and deformable matte vinyl electric wire. 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. Moreover, "gel fraction insoluble in MEK" means the extraction residue extracted with MEK at a temperature of 25° C. for 16 hours and separated using a 100 mesh filter. The characteristics of the present invention are as follows: 100 parts by weight of a vinyl chloride resin consisting of 5-90% by weight of polyvinyl chloride gel insoluble in tetrahydrofuran and the remainder soluble in tetrahydrofuran; 20-95% by weight of NBR gel insoluble in MEK; It is a vinyl electric wire coated with a vinyl chloride resin composition whose main components are 10 to 400 parts by weight of NBR made of MEK soluble material and 25 to 300 parts by weight of a plasticizer, and cannot be vulcanized or crosslinked like ordinary rubber. It has become possible to obtain creep resistance, that is, compression set, of about 25 to 40%, which is almost the same value as rubber. In other words, without vulcanization or crosslinking, the thermoplastic resin composition has a compression set of approximately
It is remarkable that it can achieve a value of 25 to 40%, which is almost the same as that of rubber. Despite the excellent properties mentioned above, unlike vulcanized rubber, it is a thermoplastic resin composition.
Recycling during molding is possible. In order to reduce the compression set, 100 parts by weight of a vinyl chloride resin consisting of 5 to 90% by weight of polyvinyl chloride gel insoluble in tetrahydrofuran and the remainder soluble in tetrahydrofuran as shown in the present invention and insoluble in MEK are used. NBR gel min 20~
95% by weight and the remainder consists of MEK solubles
It is characterized by being composed of at least three components: 10 to 400 parts by weight of NBR and 25 to 300 parts by weight of a plasticizer, and even if any one of these components is not satisfied, the compression set is as small as about 25 to 40%. There was nothing I could do. If a polyvinyl chloride resin outside the scope of the present invention is used, that is, a gel content of less than 5% by weight that is insoluble in tetrahydrofuran, or a general polyvinyl chloride resin that does not contain a gel content, the compression set will be reduced to 40%. It was difficult to do the following. Next, regarding NBR, when NBR with a gel content insoluble in MEK of less than 20% by weight was used, it was not possible to reduce the compression set at all. In order to reduce compression set, as claimed in the patent, NBR with a gel content insoluble in MEK of 20% by weight or more and 95% by weight or less was effective, but a particularly good range is found in MEK. Insoluble gel content is 40% to 90% by weight
This was the case when NBR was used. Regarding the amount of NBR added, if it is less than 10 parts by weight, there is no effect at all, and if it exceeds 400 parts by weight,
The characteristics as a polyvinyl chloride resin composition were lost, and problems such as moldability and aging properties occurred, making it undesirable. A particularly desirable range is 50 parts by weight or more and 200 parts by weight or less, which shows good compression set and workability. Furthermore, there was no significant difference in the amount of acrylonitrile added in NBR or the viscosity. Regarding plasticizers, if the amount is less than 25 parts by weight, the compression set will increase, and if it exceeds 300 parts by weight,
Productivity and workability became poor. A particularly desirable range is 40 parts by weight or more and 200 parts by weight or less, which provides good compression set and workability. Examples of such plasticizers include alkyl esters of aromatic polybasic acids such as dibutyl phthalate, dioctyl phthalate, and butylbenzyl phthalate, and alkyl esters of aliphatic polybasic acids such as dioctyl adipate, dioctyl azelate, and dioctyl sebacate. , alkyl esters of phosphoric acid such as tricresyl phosphate, etc., but there was almost no difference in compression set and processability among all the plasticizers. Regarding the polyvinyl chloride resin used in the present invention, the polyvinyl chloride resin used in JP-A-54-80354 is used, so the details are omitted, but the gel content insoluble in tetrahydrofuran is 5 to 5.
It is characterized in that the remaining 90% by weight consists of tetrahydrofuran-soluble components, and contains the following copolymers. That is, monomers copolymerizable with vinyl chloride include fatty acid vinyl ester, vinylidene halide, acrylic acid alkyl ester, methacrylic acid alkyl ester, acrylonitrile,
Examples include alkyl vinyl ale, styrene and derivatives thereof. The vinyl chloride resin composition used in the present invention can be used as it is, but if necessary, it can be blended with other thermoplastic resins, rubber, heat stabilizers, fillers, pigments, processing aids, etc. . Examples of other thermoplastic resins include general vinyl chloride resin, ethylene-vinyl acetate copolymer, chlorinated polyethylene, ABS resin, AS resin, urethane, and acrylic resin. (outside the range), CR, etc. are used. Examples of heat stabilizers include lead-based heat stabilizers such as tribasic lead sulfate, tin-based stabilizers such as dibutyltin malate, and metal soaps such as zinc stearate and calcium stearate. It is generally used in an amount of 20 parts by weight or less, and can be used as required. Fillers include carbon black, calcium carbonate, titanium oxide, talc, asbestos,
Examples include aluminum hydroxide and magnesium hydroxide, which can be used as needed, and the amount used is not limited. Examples of the pigment include color carbon black, chrome yellow, titanium oxide, and phthalocyanine green, which can be used depending on the purpose. As a processing aid, low molecular weight polyethylene,
Those commonly used for vinyl chloride resins, such as higher fatty acid esters, are used. The vinyl chloride resin composition used in the present invention can be granulated and molded by the same process as conventional vinyl chloride resins. That is, it is mixed with a plasticizer, a stabilizer, etc. using a mixer such as a super mixer or a blender, and then kneaded and granulated using a Banbury mixer, mixing roll, extruder, etc. Granulated pellets can be injection molded, extrusion molded, press molded, blow molded, calendar molded, etc. in the same way as general soft vinyl chloride resins, and the processability is as good as that of soft vinyl chloride resins. It was hot. Also, by adding NBR, it goes without saying that the oil resistance unique to NBR can be imparted.
It is coated with a vinyl chloride thermoplastic resin that satisfies the creep resistance, soldering heat resistance, shape retention at high temperatures, oil resistance, and heat aging resistance that is unique to polyvinyl chloride resin. It can be said that it is a vinyl electric wire. The technical content of the present invention will be explained using examples. Example 1 100% by weight of a vinyl chloride resin with a gel content insoluble in tetrahydrofuran of 50% by weight and an average degree of polymerization of soluble content of 1700, prepared based on the manufacturing method shown in JP-A No. 54-80354. In a composition consisting of 100 parts by weight of 2-ethylhexyl phthalate, 5 parts by weight of tribasic lead sulfate, and 1 part by weight of stearic acid,
A gel content of 70% by weight which is insoluble in MEK, and the balance being NBR soluble in MEK (acrylonitrile content: 35% by weight) were added, and the mixture was kneaded with rolls to form pellets.
This pellet was used to extrude an electric wire with an outer diameter of 2.5 mm and an inner thickness of 0.7 mm, and the workability of the wire was investigated. Further, a press sheet was prepared from this pellet, and the compression set rate and heat deformation rate were measured to evaluate the heat deformation resistance as well as the solder heat resistance of the electric wire obtained by extrusion molding of the above composition. The results are shown in Table 1. In addition, in order to compare the effect of the present invention, the gel content insoluble in MEK was 0.2% by weight, and the remainder was soluble in MEK.
NBR (acrylonitrile content: 35% by weight) was added, and electric wires were made in the same manner and evaluated.

[Table] As is clear from the results, the electric wire using NBR, which contains only 0.2% by weight of gel that is insoluble in MEK, showed no improvement in compression set or heat deformation resistance, but was insoluble in MEK. Electric wires using 10 to 400 parts by weight of NBR containing 70% by weight of gel content had good compression set, workability, and heat deformation resistance, and were particularly good in the range of 50 to 200 parts by weight. . Example 2 In Example 1, Experiment No. 5, evaluation was performed in the same manner as in Example 1, except that the type of plasticizer was changed as shown in Table 2. The amount of plasticizer added was 100 parts by weight. As is clear from Table 2, it can be seen that the compression set, workability, and heat deformation resistance are good even when the type of plasticizer is changed.

【table】

Claims (1)

[Claims] 1 100 parts by weight of a vinyl chloride resin consisting of 5 to 90% by weight polyvinyl chloride gel insoluble in tetrahydrofuran and the remainder soluble in tetrahydrofuran, and a nitrile rubber gel insoluble in methyl ethyl ketone.
Heat deformable matte vinyl coated with a vinyl chloride resin composition whose main components are 10 to 400 parts by weight of nitrile rubber, with the remainder being 20 to 95 parts by weight and the remainder being soluble in methyl ethyl ketone, and 25 to 300 parts by weight of a plasticizer. Electrical wire.