Nanocomposite acrylic paint with self-cleaning action

A nanodispersion of surface-functionalized fumed silica was incorporated into an acrylic paint formulation. SEM imaging indicated good dispersion of silica within the polymer matrix. This hybrid coating showed significantly lower dirt pick-up than the equivalent paint formulation without nanosilica additive, towards both organic and inorganic ashes. Washing with running water further decreases dirt retention. This self-cleaning performance remained unchanged after several dirt/washing cycles, during a 1-month period. Surface hardness measurements indicated no significant differences between the original and composite paint films. The lower dirt pick-up was attributed to nanoroughness created by the nanosilica particles present in the film.