Tunable shape memory property polyurethane with high glass transition temperature composed of polycarbonate diols
Hsu‐I Mao, Chin‐Wen Chen, Li‐Yin Guo, Syang‐Peng Rwei
Abstract
Abstract A series of polyurethane (PU) copolymers was synthesized by 4,4‐Methylene diphenyl diisocyanate (MDI) with different polyols of polyether, polyether carbonate (PEC), and polycarbonate with the same molecular weight via a one‐step copolymerization process. The synthesized PU containing the ether carbonate groups exhibited a relatively higher glass transition temperature ( T g ) above 45°C; in comparison, a value of 12.4°C for the polycarbonate sample and −22°C for the polyether sample was observed. The film made of PEC samples produced by solvent indicated an increment of T g from 14.6 to 59.6°C after annealing for 6 h, which might be due to the rearrangement of chain structure, which led to an assembling of carbonate groups and resulted in a hindrance of chain mobility. For shape memory examination of the PU copolymers, all samples showed remarkable ability as recovery rate above 91% after 3 cycles test. PEC‐type PU polymers reveal potential high‐temperature micro shape memory material applications.