Improved antifouling and drug delivery properties of polyvinyl alcohol hydrogel by grafting with N‐isopropylacrylamide via organic dye photocatalyzed PET‐RAFT polymerization

Polyvinyl alcohol (PVA) hydrogel was modified with NIPAAm via a green, efficient, and industrially applicable photo induced electron transfer‐reversible addition‐fragmentation chain transfer (PET‐RAFT) polymerization catalyzed by organic dye. The hydrophilicity of PVA‐g‐pNIPAAm became temperature sensitive due to the introduction of pNIPAAm polymer brushes. It was surprising that PVA‐g‐pNIPAAm became superhydrophilic (WCA = 4.3°) at 25°C while the grafting yield was 39.3%. In addition, no cytotoxic for primary human eyelid fibroblast cells was observed according to ISO 10993.5:2009. Antifouling properties of PVA‐g‐pNIPAAm were significantly improved due to the increase of surface steric repulsion effect. Drug release property of PVA‐g‐pNIPAAm was more controllable than PVA hydrogel. Thus, organic dye catalyzed PET‐RAFT polymerization could be applied to construct functional surface on biomaterials, and PVA‐g‐pNIPAAm hydrogel with lower cytotoxic, higher antifouling, and drug release properties had great potential in drug delivery. NIPAAm was grafted on PVA via FL catalyzed PET‐RAFT polymerization.