Investigation On The Construction And Performance Of MPU/ESBR Composites For High-performance Engineering Tires

With the rapid development of automobile industry,there is an urgent need to develop a high-performance rubber material for engineering tires.Emulsion polystyrene butadiene rubber(ESBR)has been one of the tire rubber materials with potential application prospects,because of good tensile,tearing and flexing properties.However,a single ESBR cannot meet the needs of high strength,high wear resistance and other properties of engineering tires.It is a practical tec hnical route that prepare a modified emulsion polystyrene butadiene rubber with high strength,high wear resistance and puncture resistance b y the compound modification of ESBR.This paper made full use of the performance advantages of mixed polyurethane(MPU),through the compound modification of ESBR,prepared a new type of composite rubber material with high-performance engineering tires,and studied its performances.The main research contents and results are summarized as follows:(1)First of all,using maleic anhydride(MAH)grafting technology to prepare a compatibilizer to achieve uniform distribution of MUP in ESBR.When compare with the compatibilizer coumarone resin,we studied the effect of improvement of MPU and ESBR compatibility with maleic anhydride grafted styrene butadiene rubber(ESBR-g-MAH)as self-made compatibilizer,Discussed the influences of grafting rate and grafting efficiency on the properties of MPU/ESBR composites,and proposed the optimal grafting process.Results shows that the a ddition of the compatibilizer ESBR-g-MAH could improve the processing safety performance of MPU/ESBR composites,the vulcanization efficiency,and the mechanical properties significantly.ESBR-g-MAH is a compatibilizer that meets the needs of the paper.Th e optimal amount of compatibilizer ESBR-g-MAH is 8%.(2)After solving the technical problems of two-phase compatibility,the MPU was introduced into the emulsion polystyrene butadiene rubber system through emulsion blending,mixing and co-vulcanization processing,etc.,improving the wear resistance and comprehensive properties of ESBR by physical blending and chemical copolymerization.The MPU/ESBR composites were prepared by two different processes: mechanical blending and emulsion blending.The structure and performance characteristics of the composites that prepared by different processes were studied by testing and analyzing the prop erties of the composites,such as vulcanization characteristics,crosslinking characteristics,thermal weight loss as well as Akron abrasion.Results shows that the performance of MPU/ESBR composites prepared by the emulsion blending process is better tha n that of the mechanical blending process.Under different MPU content,with the increase of MPU content,the torque difference of product becomes larger,and the cross-linking points in the cross-linking network with rubber compound increase,the cross-linking density increased,and the cross-linking network is more perfect;Compared with pure ESBR and MPU,the MPU/ESBR composites need less time to reach the maximum of the curing and crosslinking exothermic peak;the loss rate of the composite material's breaking strength is about under the mechanical blending process 11% and about 9%under the emulsion blending process,respectively.The performance loss rate under mixing is smaller;the elongation at break decreases between 39%-55%;the hardness of the vulcanized rubber after aging is slightly higher than that before the aging,the sample becomes harder,and the 300% tensile strength is slightly improved than the sample before aging,but the increase is not large;MPU can significantly improve the wear resistance of MPU/ESBR composites,and the wear volume can be reduced by up to 62.07%.(3)Introducing different types of carbon black and white carbon black to conduct in-depth research on the reinforcement system of MPU/ESBR composites.Us ing carbon black N220,N330,N550,N660,N774 and white carbon black 7000 GR,Z125,Z195 as different reinforcing systems to study the impact of performance,such as vulcanization characteristics,mechanical properties,crosslinking structure and dynamic properties of MPU/ESBR composites by carbon black and white carbon black.Research shown that: N220,N330,N550,N660 and N774 and other five different grades of carbon black have different reinforcing effects on MPU/ESBR composites,and N330 has the best reinforcing effect o n MPU/ESBR composites;and comparing the reinforcement effects of 7000 GR,Z125 and Z195 on MPU/ESBR composites,the composite material reinforced by 7000 GR has better comprehensive performance;When carbon black/silica multiphase reinforcement was used for MPU/ESBR reinforcement,the comprehensive performance of the reinforced composite material is better when the ratio of N330/7000 GR was 60/20.