The unusual thermal expansion behaviour of PTFE/GF composites incorporating PTFE/GF recyclate

This study examines the thermal expansion behaviour of virgin and recyclate polytetrafluoroethylene (PTFE)/glass fibre (GF) composites using two new sintering approaches - with and without pressure. In the case of composites sintered without pressure, the thermal expansion behaviour showed an unusual trace for both virgin and recycled samples. The introduction of a small amount glass fibre (<15 vol%) will increases the overall thermal expansion in the compression direction. This unusual behaviour could relate to pores entrapped and the alignment of the glass fibre in the structure. (c) 2012 Elsevier Ltd. All rights reserved.