Poly[Lactic Acid] Hemodialysis Membranes with Poly[Lactic Acid]-block-Poly[2-Hydroxyethyl Methacrylate] Copolymer As Additive: Preparation, Characterization, and Performance

Poly(lactic acid) (PLA) hemodialysis membraneswith enhanced antifouling capability and hemocompatibility weredeveloped using poly(lactic acid)-block-poly(2-hydroxyethylmethacrylate) (PLA?PHEMA) copolymers as the blendingadditive. PLA?PHEMA block copolymers were synthesized viareversible addition?fragmentation (RAFT) polymerization fromaminolyzed PLA. Gel permeation chromatography (GPC) and1H-nuclear magnetic resonance (1H NMR) were applied tocharacterize the synthesized products. By blending PLA with theamphiphilic block copolymer, PLA/PLA?PHEMA membraneswere prepared by nonsolvent induced phase separation (NIPS)method. Their chemistry and structure were characterized with X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and atomic force microscopy (AFM). The results revealed that PLA/PLA?PHEMA membranes with high PLA?PHEMA contents exhibited enhanced hydrophilicity, water permeability, antifouling and hemocompatibility. Especially, when the PLA?PHEMA concentration was 15 wt %, the water flux of the modified membrane was about 236 L m?2 h?1. Its urea and creatinine clearance was more than 0.70 mL/min, lysozyme clearance was about 0.50 mL/min, BSA clearance was as less as 0.31 mL/min. All the results suggest that PLA?PHEMA copolymers had served as effective agents for optimizing the property of PLA-based membrane for hemodialysis applications.