The objective of this study is to investigate the influence of the filler dispersion of nano-TiO2 in polymeric coatings on the surface morphology evolution of the coatings under UV exposure. Two types of nano-TiO2 with different surface treatments were chosen to mix into a water-borne butyl - acrylic styrene latex to generate different dispersion states. Two accelerated weathering conditions: wet (30 °C and 75 % relative humidity (RH)) and dry (30 °C and 0 % RH), were selected to investigate the effect of humidity on morphological development of polymeric coatings. Laser scanning confocal microscopy (LSCM) was used to characterize filler dispersion and monitor the surface morphological changes in the latex coatings during the UV exposure. Surface roughness of larger areas and localized degradation of polymer matrix around large nanoparticle clusters were investigated. It was found that morphology evolution patterns were strongly affected by nanofiller dispersion, and that severe degradation was observed around large particle clusters. Photodegradation was much faster under wet condition than under dry condition.
Proceedings Title: Proceedings of the ACS Division of Polymeric Materials: Science & Engineering
Conference Dates: August 28-September 1, 2011
Conference Location: Denver, CO
Conference Title: American Chemistry Society Fall 2011 National Meeting
Pub Type: Conferences
Accelerated weathering, morphology, nanoparticle dispersion, surface roughness, UV degradation