Effect of modified carbon black on properties of natural rubber/ polybutadiene rubber blends

Abstract

Surface modification of traditional carbon black (CB) was adopted by three methods, and the changes about the surface morphology and structure of CB before and after modification were investigated, and the modified CB was used to fill natural rubber (NR)/polybutadiene rubber (BR) blend. The effects of modified CB on the mechanical properties, curing characteristics, and dynamic mechanical properties of composites were investigated. The results showed that compared with the unmodified CB, the surface roughness of CB increased after refining particle size, raising the pH value and lignin modification. The refined CB had the higher specific area, and much more loose secondary structures for the CB with high pH value, as well as the increased particle size in lignin system slightly. For the CB filled NR/BR blend, refining particle aize and raising pH value could promote its mechanical properties, wear resistance and wet skid resistance significantly, but make an obvious vulcanization delay effect. After modification by lignin, the vulcanized blend filled with CB presented a lower mechanical properties and wear resistance varyingly.

Keywords

• modified carbon black
• natural rubber
• polybutadiene rubber
• modified method
• mecha-nical property
• curing characteristics
• dynamic mechanical property