UV Curable Coatings Based on Urethane Acrylates Containing Eugenol and Evaluation of Their Antimicrobial Activity

Abstract

This work presents studies on the obtaining of UV-curable coatings with antimicrobial activity. Urethane acrylates (UAs) have excellent physicochemical properties including high reactivity in systems with radical photoinitiators in the presence of UV radiation and good balance between hardness and flexibility in the formed coatings. At the same time, eugenol is well known as the compound hindering the growth of various microorganisms. Hence, the materials obtained by the modification of UA resins with eugenol can be used to protect various surfaces, especially against microorganisms. This study aimed to examine the influence of the amount of eugenol on the chemical, physical, thermal, and mechanical properties of the obtained UA coatings and find the conditions at which the optimal properties for industrial applications such coatings can be achieved. These materials were successfully obtained. Taking into account that eugenol is a very cheap reactant, and it can be obtained from natural sources by the simple distillation method, the proposed method combined the good points of obtaining protective coatings by UV curing with the utilization of vegetable, renewable reactants (biomass), such as components giving special properties to these materials, in this case, antimicrobial properties. In this study, photoreactive coatings with antimicrobial properties for the following microorganisms: fungi (C. albicans), Gram-positive bacteria (S. epidermidis) as well as Gram-negative bacteria (E. coli), were obtained. The obtained coatings were cured over a short time. They were colorless and characterized by a wide range of properties and applications.