Surface nanostructuring of kevlar fibers by atmospheric pressure plasma-induced graft polymerization for multifunctional protective clothing

Atmospheric plasma-induced graft polymerization was employed successfully to generate free radical on the surface of Kevlar (R) (poly-(p-phenylene terephthalamide or PPTA), and to initiate and control graft polymerization of cationic antimicrobial precursors diallyldimethylammonium chloride (DADMAC) or 3-(trimethoxysilyl)propyl-dimethyloctadecyl ammonium chloride (TMS) onto the fabric surface, which eliminates the need for separate processes that may involve thermal energy or UV irradiation. It was demonstrated that when the radiofrequency of the plasma power was 400 W, the radical density generated on the surface was 1015 to 1016 radicals cm-2, which were enough to generate a poly-DADMAC or poly-TMS with surface charge of at least 2 x 1017 N+/cm2, which is the minimum threshold for an effective cationic biocidal surface. In both cases, the grafted polymers were characterized and confirmed using SEM, FTIR, and XPS. The antimicrobial activity was measured using the AATCC Test Method 100, which showed that at least 3-log reduction of bacteria colonies was achieved in the case of grafted poly-DADMAC or grafted poly-TMS on Kevlar (R). (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012