Polysiloxane-Based Composite Coatings with Bactericidal Additives

Abstract

This paper examines the effect of both natural and synthetic additives of different concentrations to a polysiloxane matrix in order to obtain bactericidal composites. Natural additives such as black cumin, cloves, and turmeric were compared with silver, a well-known antiseptic, and with graphene, which has potential bactericidal properties. The first stage of the research included the production of polysiloxane composites with the above-mentioned powders in the form of bulk solid samples, and then a series of tests were carried out on them to not only assess their bactericidal properties but also determine their effect on physicochemical properties such as chemical structure, surface wettability, roughness, hardness, and surface morphology. Based on the obtained results, the most promising composite recipes were selected, and coatings were produced from them on a super-smooth substrate, which had been previously cleaned using a plasma chemical method. The obtained results indicated that all obtained materials were characterized by high bactericidal activity. The conducted studies also showed a significant effect of the introduced additives on the mechanical properties of the polysiloxane matrix, including graphene, which improved the hardness of the composites. Plasma chemical modification of the substrates increased the adhesion of the tested coatings to them. In addition, the effect of the used additive was also visible in this area.