Method for preparing closed-pore structure rubber foam material by mold pressing physical foaming

Abstract

The invention provides a method for preparing a closed-pore structure rubber foam material by mold pressing physical foaming. The method comprises the following steps of (1) uniformly mixing the raw rubber and the vulcanization agent, or uniformly mixing the raw rubber, the resin and the vulcanization agent; (2) carrying out hot-press molding on the obtained mixed rubber, carrying out pre-vulcanization in the hot-press molding process to obtain a rubber blank, or after the mixed rubber is formed, radiation crosslinking equipment is used for radiation so as to realize pre-vulcanization, so thatthe rubber blank is obtained; (3) putting the rubber blank into a foaming mold in mold pressing foaming equipment, inputting gas input into the foaming mold to serve as the foaming agent after the mold closing, controlling the temperature in the foaming mold to be within the range from room temperature to 80 DEG C, swelling the rubber blank body when the pressure ranges from 0.5-30 Mpa , and thenreleasing the pressure to enable the swelled rubber embryo body to be foamed; and (4) carrying out post-vulcanization on the pre-vulcanization rubber foaming material obtained in the step (1). According to the method, the quality of the rubber foaming material can be improved, and the industrial production of the high-quality rubber foaming material can be promoted.

Description

technical field [0001] The invention belongs to the field of rubber foam materials, and relates to a method for preparing rubber foam materials with closed-cell structure through molding and physical foaming. Background technique [0002] Rubber foam material, also known as sponge rubber, foam rubber or microporous rubber, is a special type of rubber material with a porous structure prepared from rubber. Compared with solid rubber, the porous structure endows foam rubber with many special properties, such as: low apparent density, soft and comfortable; good sealing performance, dustproof and waterproof; good damping performance, heat insulation, sound absorption and shock absorption, etc. Therefore, foamed rubber is widely used in sports equipment, automotive interior, aerospace, household appliances and other fields, and can be processed into various shapes and specifications according to actual needs. The original rubber foam products mostly used natural rubber or reclaim...

AI Technical Summary

Problems solved by technology

Although this method can solve the problem of warping, it still has the following deficiencies: (1) The chemical blowing agent will produce toxic gases such as ammonia and carbon monoxide during the decomposition process, and produce a pungent smell, which not only has a bad production environment, but also endangers personal health. , and pollute the environment, which is not conducive to sustainable development; after the chemical foaming agent is decomposed, small molecular chemical substances will remain in the matrix, making the product impure, having certain chemical toxicity, and affecting the performance and life of the product

(2) The decomposition of the blowing agent is a process. There are differences in the nucleation and growth of each cell (there is a sequence), which will lead to poor uniformity of the cells and a wide size distribution, and it is easy to open cells and cells. merger phenomenon

(3) This method introduces a pre-vulcanization process before foaming. The pre-vulcanization temperature is 100-130°C. At this temperature, it is almost impossible to completely avoid the decomposition of the foaming agent, so it is very easy to produce secondary foaming. It will lead to poor cell uniformity, perforation and cell merging, which will affect product performance

(4) Although the starting point of vulcanization is controlled by the pre-vulcanization process, the foaming process is still carried out simultaneously with foaming and vulcanization. The chemical foaming agent and its decomposition products will affect the vulcanizing agent, and there is still a matching of foaming and vulcanization question

[0007] Therefore, if the advantages of molding foaming and physical foaming can be combined, a method for preparing rubber foam materials, especially rubber foam thick plates, by molding physical foaming can be developed to overcome the easy warping of foam materials that exist in reactor foaming , uneven product performance and difficulty in industrial scale-up production, as well as problems such as poor cell uniformity, foaming agent and its degradation product residues, environmental protection and foaming-vulcanization matching in the use of chemical molded foaming. The quality and the realization of industrial production of high-quality rubber foam materials will have important significance and a positive role in promoting

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