| 摘要 |
<p>The present invention provides two methods for synthesizing novel titania-polyurethane (nTiO2-PU) nanocomposites for self-cleaning coatings, one a polymer functionalization method (“grafting to”) and the other, a monomer functionalization method (“grafting from”). Here, 2,2 bis(hydroxymethyl) propionic acid (HMPA) was used as the coordination agent, which was reacted with n-TiO2 (50:50 anatase/rutile) to form nTiO2-HMPA, then polymerized in the monomer functionalization method. In the polymer functionalization method, HMPA was reacted with a pre-polymer to form the PU, and then subsequently reacted with n-TiO2 to form the polymer nanocomposite. The photocatalytic cleanability of the nanocomposites was investigated when exposed to ultraviolet radiation using additional unreacted HMPA or stearic acid as the model“dirt”compounds. Nanocomposites prepared using both strategies showed similar self-cleaning behavior, although the monomer technique gave less substrate degradation.</p> |
