The beauty of injection moulding is the variation that’s possible – and the choice of thermoplastic materials available. But design freedom can come at a cost. Failures arising from incorrect material selection are not uncommon in the plastics sector, especially where designers have a complex specification to meet and little support from an experienced partner.

Considerations in polymer selection

Polymers for single or multi-shot injection moulding are typically chosen for their mechanical, thermal, environmental, electrical and chemical properties. However the demands of contemporary design also means that cosmetic finish can be as important as physical functionality – which can put more onus upon surface textures, polished features or specifically matched colours.

Polymer choice is often defined by the component’s use, so we would consider its response to a wide range of life cycle demands that the product may find itself under. This includes stresses such as impact, load, temperature, UV exposure, lifespan, and so on. The properties of the polymer when it comes to creep, stress relaxation, hygroscopicity and fatigue must also be clearly understood.

In our multi-shot applications we would also consider the strength of the bond and compatibility of the polymers used, which adds another dimension to the selection process.

Behind these decisions lies the crucial element of economic considerations. We will provide details of all of the relevant costs associated with materials, tooling and manufacture to give you clear sight of the financial commitment required to see your project take flight.


Your next steps

For advice on polymer selection and verification, get in touch and we’d be pleased to help you.

01803 615308