Structure And Properties Research Of Natural Rubber/Solution Polymerized Styrene-butadiene Rubber Composites

With the development of automobile industry and the improvement of eco-environmental protection awareness,people have higher requirements for the comprehensive performance of tires.Low rolling resistance,high wear resistance and good wet resistance become the key of preparation of tread compound with excellent comprehensive performance,and this is closely related to the tread compound material composition.Therefore,this dissertation mainly studied the effects of rubber matrix,filler system and silane coupling agent on the structure and properties of NR/SSBR composites,in order to provide guidance for the preparation and application of high performance truck tire tread compounds.(1)The compatibility of the natural rubber blended with emulsion polymerized styrene-butadiene rubber and solution polymerized styrene-butadiene rubber was compared.The results show that SSBR has better compatibility with NR than ESBR.The content of vinyl unit in SBR has a significant effect on the compatibility between NR and SBR.(2)The effects of blend ratio on the properties of NR/SSBR compounds were studied.The results showed that:SSBR reduced the vulcanization rate of the rubber compound,the tensile strength and tearing strength of the vulcanizate are all decreased.At the same time,the wear resistance of the rubber compound were improved and the dynamic compression temperature rise were reduced.The dispersion of filler was significantly improved,and NR/SSBR(60/40)compounds have better overall properties.(3)The properties of NR/SSBR composites filled with four different silicas were compared and the properties of carbon black/silica-filled NR/SSBR composites were also studied.The results showed that the silica(1165MP)filled compound has fastest curing rate,highest tear strength and modulus at 300%.The rolling resistance and dynamic compression heat rise of the rubber material are the lowest.Silica filled NR/SSBR composites has good correlation among filler dispersibility,modulus at 100%or 300%and dynamic compression heat rise.For the study of the properties of carbon black/silica-filled NR/SSBR composites,it revealed that the blend filled with 15phr silica has the highest mass fraction of bound rubber and the filler has the best dispersion.Meanwhile,the crosslink density of the vulcanizate and modulus at 300%increased,the rolling resistance and dynamic compression heat rise was the lowest.(4)The effects of silane coupling agents on properties of silica-filled NR/SSBR composites was studied.The results showed that the affinity between silica and SSBR was stronger than that of NR.The two different coupling agents increased the bound rubber content and improved the dispersion of fillers.The Si69 system has higher bound rubber content and more uniform filler dispersion.The rubber compound has a lower dynamic compression heat rise and better wet skid resistance.The wear resistance of the Si747 compound is better.