Poly[2-(methacryloyloxy)ethyl choline phosphate] functionalized polylactic acid film with improved degradation...

In this study, the surface-initiated atom transfer radical polymerization (SI-ATRP) of 2-(methacryloyloxy) ethyl choline phosphate (MCP) was successfully carried out via the ATRP initiator immobilized on the surfaces of polylactic acid (PLA) films. Different amounts of PMCP polymer brushes were constructed on the PLA surface to investigate the effects of the biological and degradation properties before and after modification. The results showed that the hydrophilicity of the surface of PLA were improved by MCP modification. In addition, there are no significant influence on the structure and crystallinity of the film before and after modification, except for the increased slightly thermal stability. Since the PMCP polymer brush forms a "protection" effect on the surface, the films showed an excellent property of resistant to hydrolysis even with obviously improved hydrophilicity. Furthermore, with the increase of the amount of introduced MCP monomer, the hydrophilicity and degradation resistance have been further improved. The in vivo animal experiment also verified this degradation resistance. Thereby, this strategy can be used to modulate the degradation rate of degradable polymers via surface modification.