ANTIBACTERIAL EVALUATION OF SOME POLYURETHANE MEMBRANES MODIFIED BY ZINC OXIDE NANOPARTICLES

In this paper a series of polyurethane (PU) membranes modified by zinc oxide nanoparticles was prepared. The polymer utilized in this study was synthesized from 1,6-hexamethylene diisocyanate (HDI), a mixture of polyesters consisting of poly(1,4-butylene adipate) diol end capped (PBA, M 2000) and polycaprolactone diol (PCL, M 2000), dimethylolpropionic acid (DMPA) as anionic centre and 1,4-butane diol (BD) as chain extender. Different concentrations of nano-ZnO powder were incorporated into the PU matrix solution in dimethylformamide (DMF). The PU/nano-ZnO membranes were prepared by precipitation in worm water, washed with distilled water and then dried at room temperature for several days. These membranes were used for Dynamic Vapours Sorption (DVS), contact angle measurements and mechanical characterization. The structure of samples was confirmed by FT-IR analysis. The antibacterial evaluation was made on Escherichia coli, a Gram-negative bacterium. The results suggest that the polyurethane membranes modified by nano ZnO have important antibacterial properties and can be used as biocidal materials.