Surface Grafting of a Quaternary Ammonium Salt on Macroporous Polyvinyl Alcohol-Formaldehyde Sponges and Their Highly Efficient Antibacterial Performance

A quaternary ammonium salt (QA), epoxypropyl-N,N-dimethyldodecylammonium chloride (EDAC), is grafted on macroporous polyvinyl alcohol-formaldehyde (PVF) sponges via facile reaction conditions. The grafting percentage (GP) of QA is influenced by the reaction temperature, time, and catalyst concentration, and the optimal GP can reach up to 43.3%. As-prepared PVF-g-QA sponges show average pore size in the range of 60-90 mu m and high porosity above 80%. Meanwhile, the resultant PVF-g-QA samples also display a high water absorption capacity approximately 12.4-14.2 g/g and reach dynamic absorption equilibrium quickly within only 1 min in both saline solution and deionized water. Notably, the antibacterial performance of these sponges for both E. coli and S. aureus are excellent with a reduction of four orders of magnitude compared with a high initial concentration of bacteria (10(8) CFU/mL). Moreover, the as-prepared samples with different grafting percentages almost have no cytotoxicity for cells. The PVF-g-QA sponges can serve as a candidate for wound dressings for medical and sanitary applications.