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Silicone rubber vulcanization process is not completed at a time, but divided into two stages, rubber material under pressure (such as molding vulcanization, vulcanization tank direct steam vulcanization, etc.) or atmospheric pressure (such as hot air continuous vulcanization) for heating shaping, known as a vulcanization (or shaping vulcanization); In the oven high temperature curing, in order to further stabilize the physical properties of the vulcanized glue, known as two stage curing (or curing).

(1) A section of vulcanization

①vulcanization of model products. Plate vulcanization, transfer molding vulcanization and injection pressing vulcanization can be used. Silicone rubber products vulcanization, generally do not use release agent, should be quickly charged, mold, pressure, otherwise easy to burn, especially containing vulcanization agent BP and DCBP glue. Transfer molded vulcanization is a kind of processing silicone rubber rubber materials widely used technology, compared with each mold single hole flat vulcanization, its advantage is short processing cycle, and can vulcanize complex rubber parts, especially with inserts and pins. Compared with injection pressure vulcanization, the equipment cost is lower. Injection pressure vulcanized mold products, can improve labor productivity, reduce labor intensity, but also can reduce the amount of peroxide, improve the tear resistance of products, improve the compression of permanent deformation performance, but the product shrinkage rate is large.

② vulcanization of extruded products. The methods of pressure vulcanization by steam, continuous vulcanization by hot air, continuous vulcanization by liquid tank, drum vulcanization and radiation vulcanization can be adopted. The first three methods are more commonly used.

(2) Two-stage vulcanization
Silicone rubber products after a period of vulcanization, some low molecular substances exist in vulcanized rubber, affect the performance of products. For example, the use of general type curing agent (such as curing agent BP or DCBP) of the glue, after a period of curing, the curing agent decomposition of acid mass, will increase the porosity of the sponge hole, reduce the density; Increasing the amount of vulcanizing agent will reduce the porosity of the sponge hole, increase the density, and produce a thicker hole wall. In addition, the curing temperature also has a great influence on the pore formation of sponge.