Development of urea formaldehyde and polystyrene waste as copolymer binder for emulsion paint formulation

Abstract

Urea formaldehyde, that is, trimethylol urea (TMU) resin was synthesized and blended with polystyrene waste (PS) to develop TMU/PS copolymer binder for emulsion paint formulation. The resulting copolymer was analysed for formaldehyde emission and other physical properties such as viscosity, gel time, density, turbidity, refractive index, melting point and moisture uptake, elongation at break and solubility in water. Infrared (IR) analysis of TMU, PS and TMU/PS showed chemical interaction between TMU and PS resins. The level of formaldehyde emission and moisture uptake were found to decrease with increase in PS concentration while, that of elongation at break on the other hand increase with increase in PS concentration. The three problems (hardness, low water resistant and formaldehyde emission) traditionally associated with TMU resin can be addressed with TMU/PS copolymer. Some physical properties of the copolymer are in agreement with the literature values of other type of binders use in paints with values within the acceptable level in the coating industry. Thus this study provides urea formaldehyde and polystyrene as a potential binder for the coating industry. Polystyrene which leads to polymer wastes is recycled and utilised for coating application.