Opacity and Washability Properties of Emulsion Paint with Natural Rubber Latex/Polyvinyl Acetate Blend Binder

Abstract

Polyvinyl acetate (PVAc) has long been known as a binder material to improve the washability, opacity (hiding power), and viscosity of commercial emulsion paints. This study aims to study the properties of opacity (hiding power), washability resistance, and viscosity of emulsion paint added with a binder from a mixture of natural rubber latex (NRL) and PVAc. Emulsion paint samples were made with a binder content of 4, 6, and 8% w/w. The binder was made from a mixture of NRL and PVAc with various NRL levels of 0%, 15%, 25%, 35%, 50%, and 100% w/w. Testing of paint samples includes washability using a digital BGD 526 Wet Abrasion Scrub Tester and viscosity testing using a HAAKE 6R digital viscometer. At the same time, the opacity test uses the Indonesian Standard (SNI 3564:2009). The results showed that the opacity met the standard emulsion paint for all binder levels, except for the composition of NRL 100% w/w at all binder levels. The higher the NRL content in the binder causes the washability resistance and paint viscosity to decrease and become unstable. The best washability resistance and viscosity properties were obtained at NRL in a binder of 15% w/w and a binder content of 8% w/w, with washability resistance properties of 50 times and a viscosity of 3300 cp.