Hydrophilic and Antibacterial Modification of Poly(lactic acid) Films by γ-ray Irradiation

[Image: see text] To improve the hydrophilicity and imparting antibacterial properties to poly(lactic acid), poly(acrylic acid) (PAA) and silver particles (AgNPs) were simultaneously introduced onto the surface of poly(lactic acid) (PLA) films by γ-ray irradiation. The morphology and structure of the modified films were characterized by scanning electron microscopy (SEM)/energy-dispersive X-ray (EDX) spectrometry and Fourier transform infrared (FTIR) spectroscopy. The interaction between PAA and AgNPs was investigated by X-ray photoelectron spectroscopy (XPS), confirming the coordination between AgNPs and the oxygen atom on the carboxylic group of PAA. The contact-angle (CA) measurements and antibacterial tests showed that the modified PLA films with a low silver content (PLA-g-PAA-Ag) exhibited excellent hydrophilicity as well as antibacterial activity compared with the neat PLA film.