Fabrication and properties of high performance PEEK/Si 3 N 4 nanocomposites

The crystallization, morphology, microhardness, scratch hardness, dynamic modulus, and wear behavior of high performance poly(ether‐ether‐ketone) (PEEK) matrix nanocomposites reinforced with 0 to 30 wt % silicon nitride (Si 3 N 4 ) nanoparticles were reported. The crystallinity of PEEK nanocomposites increases at 2.5 wt % Si 3 N 4 but, thereafter it decreases with increasing Si 3 N 4 content due to the hindrance to the ordering of PEEK chains. The crystallization peak temperature and crystallization onset temperature increases by 14°C for 10 wt % nanocomposite. The melting temperature does not vary significantly with Si 3 N 4 content. SEM shows almost uniform distribution of Si 3 N 4 in the PEEK matrix. The Vickers microhardness and scratch hardness increases significantly up to 10 wt % Si 3 N 4 content.The dynamic modulus of nanocomposites increases below and above T g of PEEK. The specific wear rate of nanocomposites with 2.5 wt % Si 3 N 4 is reduced significantly and it is lowest at 10 wt % Si 3 N 4 . However, the coefficient of friction of nanocomposites is more than that of pure PEEK. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011