Enhancement of Surface Properties on Films of Waterborne-Polyurethane Hybridized by Highly Dispersed and Aluminate-Modified Silica Sol

Abstract

The reinforced clear coat on glass substrate was prepared by coating waterborne-polyurethane hybridized by silica sol or aluminate modified silica sol. To enhance the physicochemical property of the film, aluminate modified silica particle was prepared by the interaction between sodium aluminate and cation-exchanged silica. The hybrid thin films were developed in the range of the modified silica content varying from 0 to 20 wt%. The film, containing the modified silica content of 16 wt%, exhibits markedly improved properties as compared to the neat polyurethane and the polyurethane containing silica particle; e.g., an improved hardness, chemical and abrasion resistance, with maintaining the transparence. However, the film transparence was decreased with modified silica content above 18 wt%, and its hardness was not improved with its content below 14 wt%.