Laterally crosslinked polyurethane copolymers with polycarbonate as a soft segment

The polyurethane (PU) copolymer was laterally crosslinked with an extra MDI, in which a more rigid polycarbonatediol replaced the conventional poly(tetramethyleneglycol) as a soft segment. What is the impact of the possible molecular interaction between polycarbonate soft segments and lateral crosslinking. The structural change after crosslinking and the impact of new soft segment were followed by infrared spectra, crosslink density, UV-VIS spectra, and relative viscosity. The tensile stress could improve as much as 554 % by selecting the polycarbonate soft segment and the lateral crosslinking. Shape recovery was over 90 % for the entire series and reproducible for four test cycles. The adoption of polycarbonate soft segment and lateral crosslinking significantly could improve the tensile strength and shape recovery compared to PU with polyetherdiol or polyesterdiol soft segment.