Thermoplastic Elastomer Molding Guidelines

Overmolding Design Considerations

Obtaining rubber like performance with the processing ease of injection molding is the primary benefit of TPEs. Improved cycle times and reduced scrap rates result and allow for improved part economics.

Typically, TPEs can be molded using standard processing equipment. General purpose screws are acceptable and press tonnage should ideally be 2.0 to 3.0 tons of clamp force per square in. projected over the total surface area.

TPEs are shear responsive and exhibit low viscosity when processed at high shear rates. This is an especially important factor when filling thinner walls, longer flow lengths, and overmolding situations. The one exception to this rule is with urethane-based TPEs.