Radiation grafting of 4-vinylpyridine and 2-hydroxyethyl methacrylate onto silicone rubber films, quaternization and antimicrobial properties

Abstract

A novel antibacterial system was synthesized by surface modification of silicone rubber films SR with an antimicrobial quaternized 4-vinylpyridine (4VP) and one antibiofouling 2-hydroxyethylmethacrylate (HEMA) by radiation grafting in two steps. The modification was carried out by preirradiation oxidative grafting of HEMA, then direct 4VP radiation grafting and further quaternization. The optimum grafting conditions were obtained and quaternization with alkyl bromide of the pyridine groups of the synthesized systems were realized to study the antimicrobial properties. The modified films were characterized by FTIR spectroscopy, swelling behavior, TGA, SEM and AFM.Studies on antibacterial activity with Gram-positive S. aureus and Gram-negative E. coli were determined; systems with quaternized 4VP presented more than 90% of inhibition for gram positive bacteria, and only one sample (SR-g-4VP) reached 45% of inhibition for gram negative.