Blends of semicrystalline and amorphous polymeric matrices for high performance composites

The compatibility and crystallization behavior of blends of semicrystalline and amorphous polymers, traditionally used as matrices of high performance composites, has been studied. The analysis has been focused on blends of semicrystalline poly(etheretherketone) (PEEK) with amorphous poly(etherimide) (PEI) prepared by melt mixing. Differential scanning calorimetry and thermogravimetric analysis have been used to analyze the influence of blend constituents and processing conditions on the compatibility, on the crystallization kinetics and on the final crystalline content. An Avrami model has been applied to the crystallization of PEEK in a PEEK/PEI 50/50 blend and the results have been compared with the behavior of the neat PEEK resin. The results of the characterization can be applied to predict the behavior of such blends when processed as matrix of composites or when used in the “amorphous bonding” procedure.