43. Effect of heat treatment on the parameters of crystal structure and degree of crystallinity of poly(aryl-ether-ether-ketone). Liu TX, et al. CHEM. J. CHIN. UNIV.-CHINESE 17 (7): 1142-1146, 1996.
The variations of unit cell parameters and crystallite size of nine PEEK samples treated at various temperatures have been studied by using Wide-Angle X-ray Diffraction (WAXD), The results indicate a decrease in unit cell parameter a,b and c but an increase in crystallite size L(hkl) With the increase beat treatment temperature. Based on X-ray scattering intensity theory and using the graphic multipeak resolution method, the formula of degree of crystallinity (W-c,W-X) for PEEK is derived. The results calculated are compatible with the density measurement and calorimetry.