Rubber composition, application to foam products and production method

Abstract

The invention discloses rubber composition, a processing method thereof, an application of the composition to foam product production and a method. The rubber composition is prepared from a rubber matrix and essential components, wherein the rubber matrix contains a parts of branched polyethylene and b parts of EPM rubber and EPDM rubber, a is larger than 0 and smaller than or equal to 100 parts,and b is larger than or equal to 0 and smaller than 100 parts; the essential components comprise 0.5-10 parts of a crosslinking agent and 1.5-25 parts of a foaming agent. The rubber composition applies to processing of sponge sealing strips, foam materials with high foaming ratio, damping foam rubber boards, light-color high-strength foam boards, foam solid compound sealing strips as well as solidtires filled with foam elastomers. The rubber composition has the beneficial effects as follows: branched polyethylene not only contains short branch chains of methyl, ethyl, propyl, butyl, amyl andthe like, but also contains long branch chains with carbon number larger than 6, by replacing ethylene propylene rubber in the foam rubber composition partially or completely with branched polyethylene, melt strength of the rubber composition can be improved, foamability, especially pre-foamability of the composition is improved, and the obtained rubber products have lower compression set.

Description

technical field [0001] The invention belongs to the field of rubber, and in particular relates to a rubber composition and a processing method thereof. The invention also relates to the application of the rubber composition in foamed products, and a method for producing foamed rubber products using the rubber composition , Foamed rubber products include but not limited to sponge sealing strips, high foaming ratio foam materials, shock-absorbing foam rubber sheets, light-colored high-strength foamed sheets, foamed solid composite sealing strips, solid tires filled with foamed elastomers . Background technique [0002] The vulcanization system of ethylene-propylene rubber foaming material is mainly sulfur and peroxide vulcanization system. When the sulfur vulcanization system is used, the foamed material forms a cross-linked structure mainly composed of polysulfide bonds, which has high tensile strength and high tear strength, but the heat resistance and aging resistance are ...

AI Technical Summary

Problems solved by technology

In the conventional rubber foaming process, the traditional method is to add an ultra-fast accelerator to the rubber to achieve rapid pre-crosslinking of the rubber, but this method is difficult to achieve the matching of vulcanization and foaming; One-step molding process, that is, the first molding at a lower temperature (120-140°C) for 20-50 minutes, so that the rubber has a certain degree of pre-crosslinking and begins to partially foam, and then the size is 20 times larger than the original. ~50% of the mold is heated for the second time to completely decompose the foaming agent and vulcanize and set it

In order to obtain good heat resistance, aging resistance and compression set resistance, some ethylene-propylene rubber foam materials will use a peroxide vulcanization system, and the foam material will form a single carbon-carbon crosslink bond, but compared to Sulfur vulcanization system, which also has the problem of decreased tensile strength and tear strength, and difficulty in pre-vulcanization at a lower temperature of 120-140°C

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