THERMAL-ANALYSIS OF POLY(VINYL FLUORIDE)

A sub-T(m) transition at approximately 50-degrees-C in poly(vinyl fluoride) has been attributed to a number of physical factors. We have studied this effect using differential scanning calorimetry. The rate dependence of the endothermic peak at approximately 50-degrees-C indicates that it is a second order transition. However, the recovery behavior is time dependent. It is observed in perfect head-to-tail, perfectly linear polymer and thus is not a consequence of head-to-head or tail-to-tail defects or branch points. The transition appears to be a time dependent rearrangement of the polymer chains. (C) 1993 John Wiley & Sons, Inc.