Curing Characteristics and Mechanical and Morphological Properties of Styrene Butadiene Rubber/Virgin Acrylonitrile-Butadiene Rubber(SBR/vNBR)and Styrene Butadiene Rubber/Recycled Acrylonitrile-Butadiene Rubber(SBR/rNBR)Blends

摘要

Curing characteristics and mechanical and morphological properties of styrene butadiene rubber/virgin acrylonitrile-butadiene rubber(SBR/vNBR)and styrene butadiene rubber/recycled acrylonitrile-butadiene rubber(SBR/rNBR)were investigated.Results indicated that the curing characteristics,such as scorch time,t2,and cure time,t_(90),of SBR/vNBR and SBR/rNBR blends decreased with increasing vNBR and rNBR content.At similar blend ratios,particularly up to 15phr,SBR/rNBR blends exhibited higher t2 and t_(90)compared with SBR/vNBR blends.Minimum torque(ML)and maximum torque(MH)of SBR/vNBR blends significantly increased with increasing vNBR content.For SBR/rNBR blends,ML increased with increasing rNBR content,but MH exhibited the opposite trend.Tensile strength,elongation at break(Eb),resilience,and fatigue decreased with increasing virgin and recycled NBR content in both blends.Up to 15phr,the tensile strength,Eb and fatigue life(Kc)of SBR/rNBR blends were higher than in SBR/vNBR blends.The M100(stress at 100 elongation),hardness,and cross-linking density of both blends also showed an increasing trend with increasing vNBR and rNBR content.The scanning electron microscopy study indicates that rNBR exhibited a weak rNBR-SBR matrix interaction particularly when more than 15 phr of rNBR was used,thus decreasing the mechanical properties of SBR/rNBR blends.