Abstract

Copolymerization of urea formaldehyde (UF) and urea proparaldehyde (UP) was successfully carried out. Physical properties which include gel time, viscosity, density, melting point, moisture uptake, refractive index and formaldehyde emission level were evaluated. The infrared analysis of the pure amino resins and their copolymer (UF + UP) showed chemical interaction between UF and UP resins. Resin from the copolymer showed better results on optical property, flexibility, softness, density, water resistance and lower formaldehyde emission than the conventional UF resin. Physical properties of the copolymer such as viscosity, refractive index, moisture uptake, melting point and density are in agreement with values obtained in literature for other types of binders used in paint formulation. However, the gel time is relatively too high and hence the need for inclusion of a curing agent to increase the rate of cure of the copolymer resin. UF and UP copolymer resin present itself as a potential binder for emulsion paint formulation.

Key words: Paint binder, amino resins, urea formaldehyde, urea proparaldehyde, copolymerization.