摘要 |
<p>A prepolymer composition for forming a scratch-resistant coating, comprising an acidic, aqueous solution of a polysiloxane prepolymer having non-coreactive side groups and co-reactive side groups other than hydrolysable groups, the composition being curable by evaporation of solvent and a decrease in acidity causing the co-reactive groups to react together to cross-link the polymer. Suitable co-reactive side groups are amino, epoxy and thiol. Suitable non-coreactive side groups are alkyl and gamma methacryloxy propyl. Acidity is suitably achieved by using a volatilisable organic acid such as acetic acid, so that it evaporates with the solvents to decrease the acidity.</p> |