Cooling and crystallisation behaviour during vacuum-consolidation of commingled thermoplastic composites

This paper describes the experimental and modelling results of a study on the vacuum consolidation of commingled thermoplastic composites. Samples of Twintex® glass/polypropylene (GFPP) fabric were melted, consolidated and cooled to room temperature by different cooling routes. The temperature field and the occurrence of a plateau in the through-thickness cooling profiles were modelled by coupling a non-isothermal crystallisation kinetics model with the energy equation, solved numerically using temperature-independent thermal properties for the resin. The model correctly predicted the onset of crystallisation and the degree of undercooling over a range of cooling rates. Predictions for the crystallisation rate, half-time, and temperature range agreed well with the literature data available.