Antibacterial Coatings Based on Waterborne Polyurethanes: A Review on Synthesis Methods, Properties and Applications

Today, the prevalence of bacterial infections and their resulting human and financial losses has led scientists constantly to seek solutions to develop knowledge in controlling these pathogenic microorganisms. Bacterial adhesion and their growth on different surfaces cause the accumulation of these microorganisms and the formation of biofilms. These developed microcolonies can grow and detach from the surface and spread infections. Therefore, the best way to prevent spreading the infections and diseases is to prevent the formation of biofilms using antimicrobial surfaces. In this regard, one of the most important tools introduced is the use of antibacterial polymer coatings. Polyurethanes have received much attention due to their unique properties such as biocompatibility, the possibility of using various raw materials, and controllable properties. In recent years, waterborne polyurethanes have been extensively studied due to less frequent use of volatile organic compounds (VOCs) in their preparations, easy fabrication, low viscosity, the possibility of spraying, high adhesion to different surfaces, high abrasion resistance, ability to disperse a variety of additives, and rapid film formation in biomedical fields such as antibacterial coatings, wound dressings, and biological products. In this review article, first, the various methods of preparing antibacterial polymer coatings are described. These methods include the use of nanostructures, combined with antibacterial polymers, and the use of antibacterial monomers. As a result, polyurethanes and waterborne polyurethanes have been developed. The following is a review of studies on the preparation of antibacterial waterborne polyurethanes using different strategies such as the addition of nanostructures, blending with antibacterial polymers, drug loading, the use of antibacterial monomers, and polymer surface modification. The products developed during these studies have been proposed for a variety of applications such as medical equipment coating, wound dressings and packaging industry.