Moulding of Cast Elastomers

The liquid casting system can be adapted to a variety of moulding techniques. The simplest is, of course, gravity casting into open moulds, but 

In some cases, however, it is desirable to handle these materials in a manner similar to more conventional rubbers and for this reason a compression-moulding technique is used. In this process the prepolymer and chain extender are mixed to allow the chain-extension reaction to begin, and the temperature is then reduced to slow down the final chain extension and crosslinking. In practice the hot liquid mixture is poured 

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