Facile fabrication of thermoplastic ternary copolymerized polyamide and maleated polyethylene shape memory blends

Novel thermoplastic shape memory blends of ternary copolymerized polyamide (PAM) and maleated polyethylene (PE-g-MAH) were prepared by a simple melt-blending method, which might provide a new way for the industrial production of thermoplastic shape memory materials. The new chemical bonds were generated between PAM and PE-g-MAH, which was essential for enhancement of properties. The mechanical, thermal and shape memory properties of the blends were investigated in detail. It was found that the microstructure and proportion of different constituents was vital for the shape memory properties of the blends. In PAM/PE-g-MAH blends, a crystalline region of PAM acted as a fixed domain, and the crystalline region in PE-g-MAH acted as a reversible domain. The synergistic effect of the fixed and reversible domains determined the shape memory behavior of the blends. When the blend ratio of PAM/PE-g-MAH was 30/70, the composites exhibited the best shape memory properties, with a shape fixity ratio of 95.5% and a shape recovery ratio of 79.8%.