Melt Memory Effects in Poly(butylene succinate) Studied by Differential Fast Scanning Calorimetry

Abstract

It is widely accepted that melt memory effect on polymer crystallization depends on thermal history of the material, however a systematic study of the different parameters involved in the process has been neglected, so far. In this work, poly(butylene succinate) has been selected to analyze the effect of short times and high cooling/heating rates that are relevant from an industrial point of view by taking advantage of fast scanning calorimetry (FSC). The FSC experiments reveal that the width of melt memory temperature range is reduced with the time spent at the self-nucleation temperature (Ts), since annealing of crystals occurs at higher temperatures. The effectiveness of self-nuclei to crystallize the sample is addressed by increasing the cooling rate from Ts temperature. The effect of previous standard state on melt memory is analyzed by (a) changing the cooling/heating rate and (b) applying successive self-nucleation and annealing (SSA) technique, observing a strong correlation between melting enthalpy or crystallinity degree and the extent of melt memory. The acquired knowledge can be extended to other semicrystalline polymers to control accurately the melt memory effect and therefore, the time needed to process the material and its final performance.