Polymer crystallization processes as seen from the growth front's perspective

Abstract

A critical analysis is presented regarding the possible processes that determine polymer crystal growth, based mostly on the analysis of the structure and morphology of polymer single crystals. This "forensic" analysis suggests that the interaction of the depositing stem with the growth front is the determining factor in the whole crystallization process, irrespective of any previous (pre)organization process, be it spinodal decomposition, formation of "smectic pearls" or precursor phases followed by local reorganization. This conclusion stems from the analysis of the structure and morphology of polymer single crystals, from the recognition that bulk crystallization leads to similar structures of the lamellae that build up the spherulites, and from the distinctly different structures and morphologies of polymers for which a precursor phase (with either smectic or nematic order) has been recognized. The latter situation, with an intermediate loose pre-order, prevails for polymers with inherent chain rigidity. © 2008 The Society of Polymer Science.