Properties of Natural Rubber/Styrene Butadiene Rubber/Recycled Nitrile Glove (NR/SBR/rNBRg) Blends: The Effects of Recycled Nitrile Glove (rNBRg) Particle Sizes

Abstract

The effects of different particle sizes of recycled nitrile glove (rNBRg) on curing characteristics and physical properties of natural rubber/styrene butadiene rubber/recycled nitrile glove (NR/SBR/rNBRg) blends were investigated. The particle sizes of rNBRg were differentiated by the method of sizing. S1 was obtained by cutting the rNBRg into smaller sheets; S2 was obtained by passing rNBRg through 2 rolls mill for 10 times; and S3 was obtained by passing rNBRg through 2 rolls mill for 10 times and then mechanically grinded. NR/SBR/rNBRg blends were prepared at 50/30/20 composition using two roll mill at room temperature, with different particle sizes, rNBRg (S1), rNBRg (S2) and rNBRg (S3). Curing characteristics (scorch time, cure time, minimum torque and maximum torque), tensile properties and physical properties (crosslink density, resilience and hardness) of the blends were investigated. Results indicated that scorch time, cure time and minimum torque decreased as the rNBRg particle size decreased, while maximum torque and crosslink density increased. Tensile strength of the blends decreased as the rNBRg particle size reduced, which explained the formation of holes on the surfaces of tensile fracture, observed by scanning electron microscope. The rigidity of NR/SBR/rNBRg blends increased when smaller rNBRg particles were used, which explained the increased in hardness and decreased in resilience of the blends.