Application of methylol urea/natural rubber copolymer composite for emulsion paint formulation

Abstract

This work is a follow up to our quest to develop emulsion paint from amino resin. Both pure urea methylol (MU) and methylol urea/Nature rubber (MU/NR) blend were prepared. Some physico-chemical properties such as viscosity, melting point, moisture uptake, refractive index, density, elongation at break and formaldehyde emission of both MU and MU/NR were evaluated. The result revealed that MU/NR blend possesses better water resistant, hardness, flexibility and low formaldehyde mission while the pure MU gave better refractive index. Emulsion paints were also formulated from both resins and some physico-chemical properties namely pH, viscosity, flexibility, hardness, tackiness, resistance to blistering, dry time, gloss and storage stability were investigated. Emulsion paint derived from MU/NR binder except for gloss passed the entire test conducted while the one from pure MU binder failed flexibility, adhesion, hardness, tackiness and dry time. This work presents MU/NR paint as a high quality one and hence, may introduce a novel emulsion paint derived from MU/NR binder into the coating industry.
 
Key words: Amino resin, methylol urea, natural rubber, binder, emulsion paint.