Preparation and characterization of PLA/TPU/HA enhanced shape memory blends

Polylactic acid (PLA) is an excellent smart material with favorable mechanical properties and shape memory behavior, along with low cost and broad applicability. However, its relatively high deformation temperature and poor toughness limit its application in implantable medical devices. The PLA/TPU/HA blend was prepared via physical blending to reduce the glass transition temperature ( T g ) of PLA and to enhance its shape memory performance and mechanical properties. Experimental results revealed that the addition of thermoplastic polyurethane (TPU) and hydroxyapatite (HA) reduced the T g by 7.16 ℃, improved the tensile strength by 15   MPa, and achieved a shape recovery rate of 94.1%, representing an improvement of over 10% compared to neat PLA. Furthermore, by adjusting the mixing ratios, the blends exhibited controllable deformation behavior, thus expanding their potential for biomedical applications.