Polycarbonate (PC) glycol synthesized from 1,6-hexanediol and 2-butyl-2-ethyl-1,3-propanediol (BEPD) 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-butanediol by a one-shot method. The degree of microphase separation became weaker with an increase in the BEPD 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 BEPD content, respectively.
This result clearly suggests that butyl and ethyl groups of the BEPD part suppressed the packing of the soft segment under elongation.