Abstract: Aqueous polyurethane emulsions were made by prepolymer dispersing process. Then fumed silica was added to emulsions to get silica modified aqueous polyurethane coating agent. Performance of SiO2/PU coating agent containing various dosage of fumed silica was researched. The result showed that performance indicators of emulsions were improved after appropriate dosage of fumed silica was added.

Key words: aqueous polyurethane; fumed silica; coating; moisture penetration; hydrostatic pressure resistance