Designing polymeric coating with low coefficient of friction for natural rubber glove application

Abstract

A layer of polymeric coating with low coefficient of friction (COF) on rubber glove surface is necessary for quick and easy donning. The current study elucidates the effect of varying the composition of soft and hard monomers in novel styrene-butyl acrylate-isoprene (St-BA-Iso) terpolymer on the properties of emulsion and its coating performance on rubber glove substrate. Styrene contributed to the terpolymer’s overall strength and smooth surface. Butyl acrylate, as a soft monomer, imparted flexibility and lower the glass transition temperatures of the coating. Isoprene, another soft monomer, further contributed to the coating’s flexibility and, when combined with butyl acrylate, played a role in maintaining coating adhesiveness. Terpolymers with higher loading of BA and Iso was found to produce films of relatively low glass transition temperature, Tg and higher COF. Meanwhile, high loading of St in the terpolymer resulted with smooth coating surface but exhibited severe delamination from the substrate when stretched due to the high rigidity and poor coating adhesion. St-40 terpolymer with 4 St: 3 BA: 3 Iso composition was able to produce a coating with well-balanced properties, producing smooth film (COF < 0.1) with moderately high Tg (24 °C), while retaining good coating adhesion on the rubber substrate.