Sequence Distributions and Crystallinity in Random and Semi-Blocky Polysiloxane Copolymers

摘要

According to the very early work of Flory1 and Wunderlich,2 crystallization In semi-crystallizable copolymers can be thought of as the lateral growth of a group of matching sequences of the tfystallizable component across a number of neighboring chains. Such sequences must obviously be of a minimum length, which depends on the nature of the chains, in order to thus participate in Information of a crystallite. The Flory model assumes an equilibrium between the crystalline and amorphous regions, and provides a method for calculating various physical quantities useful for predicting depressed melting points and Young's moduli ol the copolymers. Wunderltch's model, on the other hand, Is based on the statistical probability that a certain unit of the copolymer is a crystallizable unit, and Is more concerned with "cold" crystallization such as occurs in quenched materials.