Aggregation Structures and Mechanical Properties of Polyurethane Based on Polycarbonate-Glycol with Various Side Group Contents

摘要

Polycarbonate(PC)-glycol synthesized from 1,6-hexanediol and 2-butyl-2-ethyl-1,3-propanediol (BEPG) with various ratios were employed to control the mechanical property of PC-glycol-based polyurethane elastomers (PUEs). The PUEs were synthesized from PC-glycol, 4,4’-diphenylmethane diisocyanate and 1,4-butandiol by a one-shot method. The degree of microphase separation became weaker with an increase in the BEPG content. This trend results in a decrease in Young’s modulus due to the lack of the formation of crystallized hard segment domains in the PUEs. Tensile strength and strain at break decreased and increased with increasing BEPG content, respectively. This result clearly suggests that butyl and ethyl groups of the BEPG molecule suppressed the packing of the soft segment under elongation.