Why Bond Silicone Rubber

In many applications, moulded parts, soft and hard, soft and soft or hard and hard are put together in order to perform a specific task which a part made of one single material could never perform. Very often it happens that at least one of the parts consists of silicone rubber. 

Before assembly both parts are produced separately, and then combined in a separate production step, without any bond to each other. They are fixed mechanically. 

a soft elastic part is used, for example, as a gasket, valve, damper, etc. In order to attach it somewhere, a hard component is required to act as a mechanical support. 

The bonding is achieved by different methods. The hard component can contain undercuts where the rubber is anchored during its vulcanisation, a primer on the hard component or even using self-adhesive silicone rubber will give sufficient anchorage. 

The formulation of the latter contains certain adhesion promoters which allow for enhanced affinity between rubber and the other substrate. The chemical nature of self-adhesive materials in most cases is proprietary information which cannot be disclosed. But, several models for bonding are described in the literature [10]. 

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