Thermodynamic modeling of the thermomechanical effects of polymer crystallization: a general theoretical structure

摘要

A general theoretical structure is developed based on continuum thermodynamics to model the thermomechanical effects of polymer crystallization. This phase transition, seen in many polymers, involves the gradual transformation of the polymer's microstructure from an unorganized amorphous structure to that of a much more rigid semi-crystalline structure. This smooth transition is captured by a set of integral models which obtain the response by averaging the apparent response of the amorphous portion and a continuum of different crystals. A commonly used empirical relation between the extent of crystallization and volume change is imposed as a restriction on the material, and the implication of the entropy production inequality in the presence of this constraint is evaluated. General representations are provided.