AFM IMAGING OF INTERFACIAL MORPHOLOGIES IN CARBON-FIBER-REINFORCED ISOTACTIC POLYPROPYLENE

The morphology of high-modulus carbon-fiber (HM-CF) reinforced isotact ic polypropylene (IPP) was investigated for the first time by atomic f orce microscopy (AFM) using chemically etched specimens. The images ex hibited alpha-transcrystalline morphology for samples crystallized fro m quiescent melts, nucleated by HM-CF. In melts sheared by fiber pulli ng, alpha beta-cylindritic columnar morphology was observed in agreeme nt with earlier thermooptical studies. AFM images in the interfacial r egion of the beta-cylindrites unveiled fine morphological details of a lpha-row nuclei. Based on the observations, we concluded that in beta- cylindrites, the lamellar growth in alpha-row nuclei occurs during epi taxial crystallization on bundles of extended IPP chains which form du ring shearing of the polymer matrix by fiber pull.