JPH0448819B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a highly slippery soft vinyl chloride resin composition, and more particularly to a vinyl chloride resin composition comprising a vinyl chloride resin, a polyolefin resin, a chlorinated polyethylene, and a plasticizer. In general, soft vinyl chloride resin compositions made by blending vinyl chloride resin with plasticizers and other ingredients are flexible, have rubber-like elasticity, have excellent moldability, and are inexpensive, so they are used in a wide range of applications. There is. Weather strips for automobile window glass, one of its uses, are parts that are attached to the window frame and come into contact with the window glass surface to prevent wind and rain from entering the room. Therefore, extrusion molded products of soft vinyl chloride resin or rubber are used. On the other hand, this weather strip member is required not only to have good adhesion but also to have as little frictional resistance as possible at the contact portion with the glass so that the window glass can be opened and closed easily. However, conventional soft vinyl chloride resin compositions or rubbers have high frictional resistance and cannot be used as they are. Therefore, methods such as flocking or applying a paint with low frictional resistance to the contact area with the glass surface are currently used, although this increases the number of manufacturing steps and costs. Therefore, it is strongly desired that a soft vinyl chloride resin composition itself with extremely low frictional resistance be developed. As a result of various studies regarding this problem, the present inventor discovered that a composition with extremely low frictional resistance can be obtained by adding a polyolefin resin, a specific chlorinated polyethylene, and a plasticizer to a vinyl chloride resin. , we have completed the present invention. That is, the present invention uses 10 to 300 parts by weight of polyolefin resin to 100 parts by weight of vinyl chloride resin,
Contains 0.1 to 5 parts by weight of chlorinated polyethylene with a crystallinity of 5% or more and a chlorination degree of 10 to 50% and a plasticizer, and has a JIS hardness (JISK-6301A type) of 50 to 50.
95. This is a highly slippery flexible vinyl chloride resin composition characterized by having a polyvinyl chloride resin composition of 95%. The vinyl chloride resin used in the present invention is not only a vinyl chloride homopolymer, but also a vinyl chloride-based copolymer obtained by copolymerizing vinyl chloride with ethylene, vinyl acetate, vinylidene chloride, vinyl ethers, etc. It refers to a graft copolymer such as vinyl chloride-ethylene-vinyl acetate or a mixture of two or more thereof. Furthermore, polyolefin resin refers to polyolefin resins such as low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, polybutene, polyisobutylene, poly-4-methylpentene-1, etc., and a mixture of two or more thereof. . If the amount of polyolefin resin added is less than 10 parts by weight per 100 parts by weight of vinyl chloride resin, a sufficient reduction in frictional resistance cannot be expected.
If the amount exceeds 300 parts by weight, the hardness increases so much that it is difficult to reduce it with a plasticizer alone, and the phenomenon of whitening upon bending cannot be sufficiently suppressed. The chlorinated polyethylene in the present invention has a crystallinity of 5% or more and a chlorination degree of 10 to 50%. Crystallinity less than 5% and chlorination degree 1
If it is less than 50% or more than 50%, the whitening phenomenon cannot be sufficiently suppressed. Furthermore, if the amount of chlorinated polyethylene added to 100 parts by weight of vinyl chloride resin is less than 0.1 part by weight, it will not be possible to sufficiently suppress the bending whitening phenomenon, and if it exceeds 5 parts by weight, the reduction in frictional resistance will be suppressed. This is undesirable. The plasticizer in the present invention refers to a plasticizer that is generally used for soft vinyl chloride resins, and includes phthalic acid esters such as dioctyl phthalate, diisodecyl phthalate, dibutyl phthalate, and diheptyl phthalate, dioctyl adipate, and dioctyl sebacate. linear dibasic acid esters such as trimellitic acid esters, polyester polymer plasticizers, epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil, phosphate ester plasticizers such as triphenyl phosphorite, etc. They may be used alone or in combination of two or more. JIS hardness (JISK-6301A type) is 50 by adding plasticizer.
The reason why the hardness is set at ~95 is that if it is less than 50, it is too soft to be practical and the frictional resistance cannot be reduced sufficiently, and if the hardness exceeds 95, it is too hard and cannot be used as a soft material. It is preferred that the composition of the present invention contain organopolysiloxane in an amount of 0.1 to 10 parts by weight per 100 parts by weight of vinyl chloride resin, since this further reduces the frictional resistance. Examples of organopolysiloxanes include dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrodienepolysiloxane, etc., and various modified polysiloxanes shown below (w, x, y, z are integers), etc. alone or in combination. A mixture of the above is used. In addition to the above-mentioned components, the composition of the present invention also includes stabilizers, fillers, antioxidants, ultraviolet absorbers, lubricants,
Processing aids, pigments, flame retardants, etc. can be contained as necessary. The highly slippery soft vinyl chloride composition of the present invention can be molded by conventional methods such as extrusion molding, injection molding, calendar molding, and blow molding. Although it has been known to add polyolefin resin to soft vinyl chloride resin (Japanese Patent Application Laid-Open No. 1986-5842), this composition has a lower tear strength and
Moreover, the phenomenon of whitening due to bending cannot be avoided. In addition, a resin composition in which chlorinated polyethylene and an inorganic filler are added to a mixture of vinyl chloride resin and polyolefin resin is also known (Japanese Patent Application Laid-Open No. 12855/1985), but this method can achieve uniform compatibility and prevent brittleness of the composition. Therefore, it is an essential requirement that chlorinated polyethylene be added in an amount of about 5.5 parts by weight or more per 100 parts by weight of vinyl chloride resin. In contrast, in the present invention, a plasticizer and a specific chlorinated polyethylene are used, so the amount of chlorinated polyethylene used is 0.1
Not only can a homogeneously compatible composition be obtained with a small amount of ~5 parts by weight, but a molded article with high lubricity cannot be obtained when a larger amount is used than this range. Furthermore, the known method is not intended to reduce frictional resistance. Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that the numbers shown in the examples are parts by weight unless otherwise specified. Example 1 The indicated parts of the resin, plasticizer and additives shown in Table 1 were blended and kneaded for 5 minutes with a hot roll at 155°C.
After taking out the sheet, it was hot pressed at 160℃ for 5 minutes on a press plate with a matte surface with a center line average roughness (Ra) (JISB-0601) of 2.3 μm, and the sheet was heated to a thickness of 2 mm. A disk with a diameter of 60 mm was punched out to prepare a test piece, and the test piece was tested according to the following method. The results are shown in Table 1. The coefficient of static friction was determined by placing the matte surface on a smooth glass surface so that it was in contact with the glass surface, placing a load such that the weight was 100 g, gradually tilting the glass surface, and determining the angle at which the test piece began to move. The bending whitening property was determined by visually observing whether or not whitening occurred on the bent surface when the test piece was bent 180 degrees. Hardness was measured using JISK-6301A model.

【table】

[Table] *1 ○ means no whitening, × means whitening Example 2 Example of polydimethylsiloxane addition system
Shown in the table. A resin, a plasticizer, and an additive were mixed in the indicated amounts, and a test piece was prepared in the same manner as in Example 1, and measurements were performed in the same manner. The results are shown in Table 2.

【table】

[Table] *1 Same as Table 1

Claims (1)

[Scope of Claims] 1. 10 to 300 parts by weight of polyolefin resin based on 100 parts by weight of vinyl chloride resin, crystallinity of 5% or more,
Chlorinated polyethylene with degree of chlorination 10-50% 0.1-5
1. A highly slippery soft vinyl chloride resin composition for a weather strip member, characterized in that it contains parts by weight and a plasticizer, and has a JIS hardness (JISK-6301A type) of 50 to 95. 2. For 100 parts by weight of vinyl chloride resin, 10 to 300 parts by weight of polyolefin resin, crystallinity of 5% or more,
Chlorinated polyethylene with degree of chlorination 10-50% 0.1-5
A highly lubricating soft material for weather strip members, which contains 0.1 to 10 parts by weight of organopolysiloxane and a plasticizer, and has a JIS hardness (JISK-6301A type) of 50 to 95. Vinyl chloride resin composition.