Study on Shape Memory Effects of LC Epoxy Resins with Lateral Substituents
A series of shape memorized liquid crystalline epoxides with different length of lateral substituents were prepared with several kinds of hardener. The dynamic mechanical analysis and the sharp memory properties of the resulted LC epoxy resins were studied by POM, WAXD, DSC and DMA. The results showed that the modulus in the rubbery region (ER) of the LC epoxides decreases as the length of lateral alkyl groups increases. And the shape memory properties were strongly impacted not only by the length of lateral substituents, but also by the kinds of hardener. The recovering speeds of the shape-memory liquid crystalline epoxides decrease as the increasing length of lateral alkyl groups. And recovering speeds of LC epoxides cured with aromatic amine (DDM) are faster than that of LC epoxides cured with anhydride (THHPA). The local ordered structures and the lateral substituents played an important role in shape memory effects.
Yuan Ming Huang
L. Y. Liang et al., "Study on Shape Memory Effects of LC Epoxy Resins with Lateral Substituents", Key Engineering Materials, Vols. 428-429, pp. 391-393, 2010