Choosing the most suitable elastomer is a critical issue in many automotive thermoplastic molding projects.
Here are some ideas for guidance:
Thermoplastic elastomers or thermoplastic rubbers (TPEs) are becoming increasingly popular in the automotive and transportation industries. They are used, for example, as a replacement for traditional tires, compared with which they are more cost-effective.
Applications in this area are generally very complex, as they often require the combination of mechanical performance and aging resistance. Those related to the engine compartment, for example, require high thermal resistance and good resistance to hydrolysis and chemicals. Most exterior components, on the other hand, require good chemical and weathering resistance.
A diverse family
TPEs are a broad and diverse class of materials. Polymers suitable for thermoplastic molding in the automotive industry include:
- thermoplastic styrenic elastomers (TPS)
- olefin thermoplastic elastomers (TPO)
- olefin block copolymers (OBCs).
- vulcanized thermoplastic elastomers (TPV)
- thermoplastic polyurethanes (TPUs)
- the thermoplastic elastomers ether-to-ester (TPC)
- thermoplastic polyamides (TPA)
All of these materials offer not only unique mechanical and thermal property profiles, but also exhibit different aging when exposed to heat, chemicals, water and weathering. As a result, choosing the most suitable TPE is not a simple process.
The Ansa Composites Group has the know-how to indicate the most suitable type of material for thermoplastic and thermoset molding.
Car exterior applications
Many automotive exterior applications are exposed to long-term environmental stresses, high temperatures and the action of water, so they impose high resistance to hydrolysis and weathering.
Among all TPEs, those most suitable for thermoplastic or thermoset molding of these components are in general:
- TPS
- TPV
They offer resistance to hydrolysis and do not change their properties significantly.
Other types such as TPC ether-ester and TPU ester can be stabilized against hydrolysis by adding specific additives.
Undercounter applications
Thermoplastic elastomers are used for thermoplastic and thermoset molding of numerous under-hood applications, processes that impose very different requirements on the polymer. Most components installed near the motor require:
- resistance to hydrolysis
- very high mechanical properties
- flexibility at low temperatures
- wear and abrasion resistance
- resistance to oils, greases
- lubricants and saturated hydrocarbons
The right choice for thermoplastic molding
As we have seen, not all TPEs are suitable for the production of auto parts and underbody. Material selection is a critical issue in the development of a new part or in situations where you want to replace the polymer in use. Ansa Composites Group’s technical service department can provide valuable support not only in material selection, but also in thermoplastic and thermoset design and molding.
