Recycled rubber powder is a typical application of recycling of waste rubber resources. It is widely used in the rubber field and non-rubber field. It is a kind of blending of EPDM rubber as filler and chlorinated polyethylene rubber to produce foaming material. Important application. In theory, the main raw material of EPDM rubber powder is EPDM scrap or waste EPDM rubber, which is excellent in aging resistance, corrosion resistance and weather resistance. In the foamed material with chlorinated polyethylene rubber as the main raw material. Can be filled in a lot. Then, in actual production, what kind of place does the EPDM rubber powder need to pay attention to in the chlorinated polyethylene rubber foaming material, and what role can it play?
1. The role of EPDM rubber powder in CM foaming materials
In the chlorinated polyethylene rubber foaming material, the EPDM rubber powder does not foam as a filler itself, and does not cause shrinkage. Therefore, the foaming shrinkage ratio of the composite foaming material increases with the amount of EPDM rubber powder. Large and continuous reduction; a small amount of EPDM rubber powder dispersed in CM can be used as a foaming nucleation point to increase the release of foaming agent in the material and increase the expansion ratio; EPDM rubber powder has a certain chlorinated polyethylene rubber matrix. The reinforcing effect can appropriately increase the tensile strength of the foamed material; the EPDM rubber powder can withstand partial pressure and increase the compressive strength of the foamed material; the cross-linking bond of the surface of the modified EPDM rubber powder will occur during the reaction process. The fracture generates new free radicals. During the foaming and vulcanization process, the surface of the rubber powder and the CM matrix also crosslink, and the interfacial compatibility increases, which makes the foamed material uniform and the crosslinked network more uniform, and the cell structure is denser. ,more complete.
2. Adding skills of EPDM rubber powder in CM foaming materials
The molecular chain in the EPDM rubber powder is highly aggregated and entangled, resulting in a vacant volume with the chlorinated polyethylene rubber base member, which hinders the movement of the macromolecular chain. Therefore, the foamed material door with the EPDM rubber powder is added. The viscosity of the foam will be improved; the hardness of the foamed material will be determined according to the thickness of the pore wall of the foamed material, the amount of EPDM rubber powder will increase, the pore wall will become thinner and thinner, and the hardness will decrease; excessive waste ternary Ethylene-propylene rubber powder will reduce the wall thickness of the foamed material and damage the physical and mechanical properties of the material (including tensile strength, elongation at break, etc.).
Therefore, in order to ensure the performance and service life of chlorinated polyethylene rubber and EPDM blended foam materials, product manufacturers need to properly control the amount of EPDM rubber powder added; modified EPDM rubber powder to chlorinated polyethylene rubber foam material The negative impact of Mooney viscosity, vulcanization performance and physical and mechanical properties is even smaller. Foam material manufacturers can choose to blend modified EPDM rubber powder with chlorinated polyethylene rubber to produce better foam materials. The use of waste EPDM rubber powder in foaming materials can not only improve the comprehensive index of foaming materials, but also realize the recycling of waste resources.