Crosslinking process, mechanical and antibacterial properties of UV-curable acrylate/Fe3O4-Ag nanocomposite coating

In this paper, an antibacterial nanocomposite coating has been prepared by a green method based on photo-croslinking with the addition of new synthesized Fe3O4-Ag nanohybrids. Fe3O4-Ag hybrid nanoparticles (0.1 wt. %) were dispersed in UV-curable acrylate resin stystem (BGDM and HDDA). The kinetic of UV-curing reaction of the nanocomposite was studited by measuring the coversion of acrylate double bonds, the variation of relative hardness, gel fraction and swelling degree of the coating. The structural morphology, mechanical and antibacterial properties of the nanocomposite were characterized. The analysis data demonstrated that the addition of 0.1 wt.% of Fe3O4-Ag hybrid nanoparticles into the coating affected insignificantly to its crosslinking process; the UV-exposure time to achieve a full crosslinking coating was about 4.8 s; the hybrid nanoparticles were homogeneously dispersed in network polymer matrix. The addition of the nanohybrids into the UV curing coating improved its its abrasion resistance from 98.24 to 126.54 lite/mil. The antibacterial testing indicated that the antimicrobial activity of the nanocomposite against E. coli was inversely proportional to its crosslinking density. Adding the nanocomposite in the culture, the growth rate of culture reduced about 3-5 % compared to that of the pure culture, after 5 h of cultivation while no antibacterial activity was observed for the neat coating.