RTM goes thermoplastic
Researchers in Germany have come up with a method of applying the basis of resin transfer moulding – RTM - to make fibre reinforced thermoplastic composite parts to improve vehicle crash resistance, that are half the weight of equivalent aluminium parts.
The idea comes from the Fraunhofer Institute for Chemical Technology ICT in Pfinztal which has christened the process, thermoplastic RTM or T-RTM. In it, a pre-heated carbon or glass fibre structure is placed in a temperature controlled mould tool. This is followed by injecting an activated monomer melt into the moulding chamber, which contains a catalyst and activator system that causes polymerization within the mould.
According to Dipl. Ing. Dieter Grittel, project manager at ICT, "The cycle time to produce thermoplastic components is only around five minutes. Comparable thermoset components frequently require more than 20 minutes". Cost is said to be about half that of a thermoset equivalent, and furthermore, the thermoplastic part can be recycled, whereas the thermoset equivalent cannot.
A demonstration part that has been made is a trunk liner for a Porsche Carrera 4 that weighs up to 50% less than the original aluminium part.
