Synthesis and Characterization of Antibacterial Polyurethanes Coatings from Novel Quaternary Ammonium Functionalized Soybean Oil-Based Polyols

In the present work quaternary ammonium containing polyols were prepared by reacting epoxydized soybean oil (ESBO) with diethylamine and further quaternization with either benzyl chloride or methyl iodide. These new renewable resource based functional polyols were used for the preparation of polyurethane coatings via reaction with proper diisocyanate monomers. The biocompatibility and antibacterial properties as well as some mechanical and physical properties were evaluated for these new materials. All of the cured films showed complete curing with gel content more than 95%. DMTA thermograms showed two phase structure with soft and hard segment glass transitions in the range of 0-15 °C and 140-170 °C respectively. According to stress-strain curves, the prepared films showed tensile strength and elongation at break of 5-9 MPa and of 16-87% correspondingly. Depends on the quaternizing group and diisocyanate structure the surface hydrophilicity of films were altered. Samples made from aliphatic diisocyanates and methyl iodide as quaternizing group showed higher surface hydrophilicity. The solvent resistant of coatings based on MEK rub test was excellent. Cell culture test and MTT assay based on mouse L929 fibroblast cells indicated of noncytotoxcicity and cytocompatibility of prepared polyurethanes. Films prepared from benzyl chloride based quaternized polyol had no bactericidal function, however, the samples made from polyol quaternized with methyl iodide showed significant bacterial reduction in the range of 79-88%.

Keywords:

Soybean Oil-Based Polyol , Polyurethane , Antibacterial Coating