Different rubber compounds need to be combined with raw rubber and different additives through different formulations and production processes. For silicone rubber, the skill depends on the compounding of the compound.
At present, China's raw rubber production technology is relatively mature, the competitiveness of the silicone rubber market depends on the quality of silicone rubber compound, production process performance and finished product performance. The gap in rubber levels in various regions is also mainly reflected in the compounding of rubber compounds.
Silicon rubber ingredient additives are mainly white carbon black. The finely dispersed white carbon black has a high reinforcing coefficient for the silicone rubber raw rubber, the raw rubber is 40, and the index for styrene butadiene and nitrile rubber is about 10. In addition to silica and inert fillers, the compounding ratio of silicone rubber includes structure control agents, vulcanizing agents or catalysts, and additives. The function of the structure control agent is to block the structuring tendency of the rubber compound. For additives, such as high-temperature rubber additive ferric oxide. Additives for high temperature thermal conductivity, metal oxides, calcium fluoride, etc.
The mixing process of high temperature vulcanized silicon HTV rubber compound is: first mix the raw rubber, filler, structure control agent and other additives into a dough shape in a closed kneader, and then knead the mixed wool material on an open mixer , After filtering by the filter glue machine, packaging. Room temperature vulcanized silicone rubber RTV compounds generally contain more inert fillers to improve their fluidity. Two-component RTV silicone rubber needs to be refined on the mixer, and the rubber compound is packaged after heat treatment and filtration.