Preparation and properties of waterborne polyurethane: application for coating 560 on natural rubber gloves

Abstract

Waterborne polyurethane (WPU) was prepared by prepolymer mixing process at room temperature from the reaction of toluene diisocyanate, polyether polyol and 2,2 bis (hydroxymethyl) propionic acid (DMPA). Upon the neutralization of carboxyl group in DMPA with triethylamine, the NCO-terminated polyurethane ionomer was selfemulsified during adding water with vigorous stirring. The resulting ionomer was then chain extended by diethanolamine in aqueous phase. The study showed that increasing the dosage of DMPA, viscosity and pH value of WPU were increased. On the contrary, the average particle size and surface tension of WPU were decreased. The study was also found that tensile strength and friction coefficient of WPU film was increased but elongation at break of WPU film was decreased. Moreover, WPU 5% coated natural latex film showed inferior tensile strength and elongation at break than uncoated natural latex film. However the PU coated natural latex film showed significantly decreasing of friction coefficient value than uncoated natural latex film.