The Impurity Effect on the Growth Mode and Lateral Habit of Polymer Single Crystals

抄録

A model of growth of polymer single crystals is presented, taking account of the effect of impurity on secondary nucleation and growth process. The impurity on growth steps interrupts further crystallization of molecules on the steps. This effect gives rise to rounded lateral habits for single crystals of poly(ethylene oxide), branched polyethylene and linear polyethylene. A once folded chain stem on extended chain crystal surface as well as small branch and adsorbed solvent have the effect of impurity, respectively. The effect on the growth mode and lateral habit is analytically derived by kinetic equations. The results are applied to supercooling dependence of growth rate and lateral habit of polyethylene single crystals grown from poorer solvents.