Preparation and properties of gelatin hydrolysate modified with polysiloxane quaternary ammonium salts

PSiQAEp-GH polymers were synthesized by the reaction of gelatin hydrolysate (GH) and polysiloxane quaternary ammonium salts containing epoxy group (PSiQAEp) with different molecular weight from 3147 to 12996. The results of FTIR, H-1 NMR and C-13 NMR showed that the reaction occurred between primary amino group of arginine in GH and epoxy of PSiQAEp. The XRD and DSC studies showed that the degree of short-range order of PSiQAEp-GH reduced and its glass transition temperature (Tg) lowered more than 10 degrees C compared with GH. The determinations of moisture absorption and contact angle (CA) indicated that the hydrophobility of PSiQAEp-GH was better than GH. The tests of inhibitory zone and minimum bactericidal concentration (MBC) illustrated that the PSiQAEp-GHs exhibited excellent antibacterial activity, and the antibacterial activity depended on both the chemical structure of PSiQAEp-GHs and the biological structure of the bacteria.