Improvements of antimicrobial and barrier properties of waterborne polyurethane containing hydroxyapatite-silver nanoparticles

Abstract

Three series of waterborne polyurethane (WBPU)/hydroxyapatite (HA) nanocomposite dispersions were prepared with varying HA and 2,2-dimethylol propionic acid (DMPA) content. It was found that the homogeneous distributed HA was highly dependent on the HA and DMPA content, with homogeneous HA found with up to 0.56, 0.95, and 1.33 mol% HA content with respect to 17.03, 22.05, and 24.02 mol% DMPA content, respectively. The hydrogen bonding increased with increased HA content in each series. The tensile strength, Young’s modulus, glass transition temperature, and water vapor permeability (WVP) resistance all increased up to the optimum HA content. The maximum tensile strength, Young’s modulus, glass transition temperature, and WVP resistance were found with 1.33 mol% HA and 24.02 mol% DMPA content, the concentrations at which the maximum homogeneous dispersed HA was observed in the WBPU/HA nanocomposites. A strong antibacterial property was also recorded when 1.33 mol% HA and 24.02 mol% DMPA content in hydroxyapatite-silver polyurethane (WBPU-C/HA3-Ag) coatings were tested against Escherichia coli and Staphylococcus aureus.