ZnO Deposited on Natural Rubber Films by Different Coating Methods

This study was focused on the incorporation of ZnO on natural rubber (NR) films using acrylic as a binder. Firstly, the dispersion of ZnO was prepared by dispersing ZnO into a mixture of acrylic emulsion and sodium cocoyl isethionate (SCI). The concentrations of acrylic emulsion were observed at 0.1 % and 0.5 %w/v while the ratio of ZnO:SCI was fixed at 1:0.25. The result shows higher concentration of acrylic emulsion could provide higher dispersion stability compared to the lower concentration. Subsequently, NR films were coated with ZnO through two-pot and one-pot methods. It was found that the surface of NR film from two-pot method (2P_film) presented uneven distribution of the ZnO while plate structure of ZnO and acrylic were observed on films surfaces one-pot method (1P0.1_film and 1P0.5_film). The Zn content on 2P_film surfaces observed by EDS was found at 14 % while 1P0.1_film and 1P0.5_film contain at 28 % and 19 %, respectively, due to higher concentration acrylic emulsion results a greater polymer network anchoring on the ZnO. The reductions of antibacterial of 2P_film, 1P0.1_film and 1P0.5_film are similar results at over 99%. It reveals that the low content of ZnO could sufficiently achieve an excellent antibacterial performance. Nevertheless, the lower concentration of ZnO/Acrylic will be conducted in further study.