Noncovalent Cross‐Linked Network‐Reinforced High‐Toughness Polyvinyl Alcohol/Hyperbranched Polyester Films Obtained Through Solution Blending

ABSTRACT Polyvinyl alcohol (PVA) exhibits good water solubility, biocompatibility, and gas barrier properties. It is an important renewable and biodegradable polymeric material and is widely used in drug delivery, food packaging, tissue engineering, etc. However, its application is limited by insufficient mechanical performance. Hyperbranched polymers are a class of highly branched, structured macromolecular polymers with multiple branching sites and rich end functional groups. In this work, blend films were prepared by mixing PVA with water‐soluble hyperbranched polyester (HBPE) using the solution casting method. The results showed that the hydroxyl groups of HBPE could form a hydrogen‐bond‐based cross‐linking network with the hydroxyl groups of PVA. This, in turn, will effectively improve the mechanical properties, water absorption, thermal stability, etc. of the blend film. When the mass ratio of HBPE to PVA is 1:4, the elongation at break of the blend film was 404.23% with a tensile strength of 39.97 MPa. The prepared PVA/HBPE blend material is expected to be more widely applied in fields such as tissue engineering, packaging materials, etc.