Is crystallization from the melt controlled by melt viscosity and entanglement effects?

Abstract

An estimate is made of the time required to reel in a polymer molecule from the melt onto the growing crystal surface. Two models, one a reptation model involving transport within a worm-hole (tube-flow), one a more conventional model, both yield reeling-in times which are orders of magnitude faster than a recent estimate by Flory and Yoon. These times are shown to be consistent with crystal growth rate data. Experimental and theoretical evidence is adduced to show that polymer chains disentangle during crystallization.