Long-range effects of carbon fiber on crystallization of semicrystalline thermoplastics

Non-isothermal crystallization of carbon fiber reinforced polyetheretherket one composites was studied with differential scanning calorimetry and Fouri er transform infrared spectroscopy. Composite prepregs prepared by a soluti on pre-impregnation method with the matrix of different molecular weights w ere employed in the present work as the main model materials. Analyses of t he different dependencies of non-isothermal crystallization on melt residua l time in these systems revealed that carbon fibers had long-range effects on bulk crystallization of matrix polymer, which is rooted in the fact that the fibers tend to promote strain-induced nucleation in polymer. Compariso n of the crystallization behavior of prepregs with that of the composite la minates indicated the importance of wetting and absorption to the effects o f fiber on matrix crystallization, coinciding with the mechanism that short -range interaction formed the boundary to the flow under thermal stress. (C ) 1999 Elsevier Science Ltd. All rights reserved.