Condensation of two-component RTV silicone rubber-...

Condensation of two-component RTV silicone rubber model Note durability, in addition to the mechanical strength of silicone rubber, and the degree of structure of the model surface, the variety and distribution of the injection molding material injection molding times a day. The impact of these physical and chemical mold release gradually disappear, and the final injection molding products and model surface damage can not continue to use. Note type of unsaturated polyester occasions, the olefin resin containing styrene in the cured silicone rubber model easy to penetrate the interface of the silicone rubber model, and occurred within the silicone rubber polymerization, the model formed on the surface of silicone rubber and the polystyrene used to each other network structure, and gradually decreased with the increase in the concentration of the model surface of polystyrene, mold release, and the formation of a layer of white hard shell, this damage is usually referred to as "burning mode". Very easy to burn the surface of the mold shaped resin injection pay, ejection model surface breakage lose value. Injection molding resin, polyurethane occasions, may also occur the chemical attack of the isocyanate component on the surface of the silicone rubber model Silastic excess crosslinker hydrolysis of the Si --- OH group and the isocyanate reaction the formation of copolymers with unsaturated polyester ester occurred, like burned mold, mold release gradually decreased, and finally lost the practicality. To suppress this phenomenon of the burning mode, there have been in the program add silicone rubber model of the surface coating release agent and base compound and the release agent. From the polymer / crosslinker - content, filler species and to meet the amount of catalyst types and meet the amount of silicone rubber formula for solutions, but have varying degrees of forming precision is not enough, and complex process, anti-burn model is not obvious such as lack. More effective method is to add anti-burn mode agent in the base material or curing agent.