Effect of Zinc Oxide Level on Tensile Properties of a NR/SBR Composite

Abstract

The aim of this work is studying the effect of zinc oxide level on tensile properties of the compounds. Since the compounds consist of natural rubber (NR) and styrene-butadiene rubber (SBR) with ratio (50:50).This work included studying the replacing of conventional zinc oxide by nano-zinc oxide as an activator has small particle size and large surface area in comparison with conventional zinc oxide so as to improve tensile properties and reduce the amount of zinc oxide inside the compounds. In this work, two groups of compounds are prepared:
 Six compounds have conventional zinc oxide as an activator with concentrations (0,2,4,5,6,8 phr (part per handred)).
 Nine compounds have nano-zinc oxide as an activator with concentrations (0,0.2,0.4,0.6,0.8,1,1.2,1.4,1.6 phr).
 The compounds were prepared by two-roll mill and laboratory press. Dumbbells (test samples) of tensile test are prepared by Wallace. Test Specimens Cutting Press. Tensile test carried out by Monsanto T10 Tensometer. Crosslink density tested by swelling the samples of the compounds by toluene and using Flory- Rehner equation. The results refer to the maximum values of tensile properties of a NR/SBR blend with conventional zinc oxide at (5 phr) of zinc oxide level. The maximum values of tensile properties with nano-zinc oxide at (1.2 phr) of zinc oxide level. The replacing conventional zinc oxide by nano-zinc oxide reduces the cost of the compounds by reducing the amount of zinc oxide inside the compounds and improves the tensile properties.