Surface Functionalization of Polypropylene Film via UV‐Induced Photografting of N‐Vinylpyrrolidone/Maleic Anhydride Binary Monomers

Abstract

AbstractSummary: A polymeric surface with desirable wettability and versatile reactivity was facilely fabricated by UV‐induced surface photografting of N‐vinylpyrrolidone (NVP)/maleic anhydride (MAn) binary monomers, with polypropylene (PP) film as a model substrate. It was found that the photografting process of NVP/MAn is much faster than that of individual NVP or MAn; both the grafting efficiency (Eg) and grafting yield (Yg) reach a maximum at around 1:1 molar feed ratio of NVP to MAn. These results indicate that the electron donor‐acceptor monomers can synergistically promote surface photografting by a known charge‐transfer‐complex (CTC) mechanism. Moreover, the grafted NVP and MAn units cooperatively enhance the surface hydrophilicity; the water contact angle of the modified surface drastically decreases from the original 99.4° to less than 36° within 30 s of irradiation time. Subsequently, we demonstrated that the surface‐grafted succinic anhydride groups could readily perform a variety of organic reactions such as acidic/alkaline hydrolysis and esterification, which is expected to facilitate further surface functionalizations. Besides, the complexing reaction of surface pyrrolidone groups with iodine was investigated, which was followed by UV‐vis spectroscopy. The antimicrobial activity against Escherichia coli, Staphylococcus aureus and Candida albicans show that this unique iodine‐complexated surface has desirable antimicrobial property.Surface photografting of NVP/MAn and post reactions of surface‐grafted anhydride groups and pyrrolidone groups.imageSurface photografting of NVP/MAn and post reactions of surface‐grafted anhydride groups and pyrrolidone groups.