γ-transcrystallization in isotactic polypropylene-based composites promoted by aramid fibers

γ-Crystallinity is the rarest form of isotactic polypropylene (iPP). Crystallization on fiber surfaces - transcrystallization - is a well known phenomena, generated by the relatively high nucleus concentration at the fiber surface which induces laterally restricted crystal growth. iPP β-oriented crystallinity can be induced either under shear stresses produced by pulling on the fiber or by using a specific nucleating agent. An experimental technique which produces γ-transcrystallinity of significant thickness and to confirm its characterization by X-ray diffraction was examined.