3.add molding room temperature vulcanized silicone rubber

The two component RTV silicone rubber can be divided into elastic silicone gel and silicone rubber, the former has lower strength, the latter has higher strength. Their vulcanization mechanism is based on the vinyl group (or propylene group) on the organic silicone rubber end group and the silohydrogen group on the crosslinking agent molecule addition reaction (hydrosilication reaction) to complete.

In this reaction, the hydrogenated functional polysiloxane is used as a crosslinking agent (vulcanizing agent) chloroplatinic acid or other soluble platinum compounds are used as catalysts. The vulcanization reaction takes place at room temperature. No by-products are released. Because the low molecular matter is not released in the process of crosslinking, the molding RTV silicone rubber does not shrink in the process of vulcanization. This kind of vulcanized rubber has the advantages of non-toxic, high mechanical strength, excellent hydrolysis resistance stability (even under high pressure steam), good low compression deformation, low combustion, deep vulcanization, and vulcanization speed can be controlled by temperature, etc., so it is a kind of silicone rubber developed strongly at home and abroad. The packing method of RTV silicone rubber is generally divided into M and N components: the catalyst and organic silicon polymer containing vinyl energy group as a component; Hydrogen - containing polysiloxane crosslinking agent as another component.

High strength molding RTV silicone rubber is an excellent material for molding because of its low linear shrinkage and low molecular release when curing. It has been widely used in the mechanical industry to mold casting epoxy resin, polyester resin, polyurethane, polystyrene, vinyl plastics, paraffin wax, low melting point alloy, coagulation and so on. Taking advantage of the characteristics of high simulation, no corrosion, simple molding process and easy demoulding, it is suitable for the replication of cultural relics and arts and crafts.