Influence of composite preform fabrication on the integrity of poly-aryl-ether-ketone matrices

摘要

Poly-Aryl-Ether-Ketones (PAEK) matrices of different composite preforms were evaluated to assess the influence of the preform manufacturing on the matrix integrity. Yarns, films, and impregnation suspensions were characterized by gel permeation chromatography, Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and rheometry. As described in literature, changes in the matrix properties at molten state are observed for all materials. The degradation process is related to a crosslinking process that results in an increase of viscosity and a decrease of crystallization temperature. Differences in degradation behavior were observed depending on the type of preform. Film and yarn extrusion has a limited effect on PAEK behavior, apart from a slight shift in molecular weight, without significant effect on degradation kinetics. However, the organic products that are used for the preparation of semifinished composite products, that is, yarn sizing or suspension additives, have a detrimental effect on stability. The degradation of additives considerably increases the degradation kinetics of the PAEK matrices, and by modifying the thermo-oxidation mechanisms, the advantages of using complex preforms for consolidation can be annihilated.