Cure characteristics, swelling behaviour and tensile properties of carbon black-filled Natural Rubber (NR)/Chloroprene Rubber (CR) blends in the presence of alkanolamide

The cure characteristics, swelling behaviour and tensile properties of carbon black (CB)-filled natural rubber (NR)/chloroprene rubber (CR) blends in the presence of alkanolamide (ALK) were investigated. The NR/CR blends were prepared at 50/50 blend ratio. The ALK was prepared from Refined Bleached Deodorized Palm Stearin (RBDPS) and diethanolamine and added into the CB-filled NR/CR blends as a rubber additive. The ALK loadings were 0.0, 1.0, 3.0, 5.0 and 7.0 phr. It was found that the ALK exhibited shorter scorch and cure times and higher elongation at break of the CB-filled NR/CR blends. The ALK also exhibited higher torque differences, tensile modulus and tensile strength up to 5.0 phr of ALK and then decreased with further increases in the ALK loading. The swelling test proved that the 5.0 phr loading of ALK caused the highest degree in crosslink density of the CB-filled NR/CR blends.