| With the continuous development of the rubber industry,the requirements for processing technology and comprehensive performance of rubber products are getting higher and higher.Rubber processing additive is an important rubber additive which can reduce the energy consumption of rubber processing,improve processing performance and quality of product.However,traditional processing additives have shortcomings in performance or cost,and the problem of easy migration and volatilization of small molecule processing additives has not been completely solved,which will reduce the use efficiency of additives and cause environmental pollution.On the other hand,various application of rubber products are indispensable to suitable modified fillers.As a widely used reinforcing filler,silica has the problem that it is difficult to be uniformly dispersed and easy to agglomerate due to its surface characteristics.Therefore,suitable surface modification technology to improve the reinforcing effect of silica is also an important issue in the rubber industry.Based on the development of“green tires”,this paper prepared new environmental friendly reactive filler-supported processing additives for the development of high performance composite materials and the surface modification of silica.Here,three kinds of fatty acid:stearic acid（SA）,oleic acid（OA）and linoleic acid（LA）were used to prepare a reactive supported processing additive SiO2-s-SA,SiO2-s-OA,SiO2-s-LA,and the improvement on the processing properties of the rubber compound,filler-rubber interaction were fully discussed,Meanwhile,the effect of reactive silica-supported processing additive on the structure and properties of styrene-butadiene rubber composites had been investigated systematically.The main contents are as follows:（1）Firstly,six typical processing aids were studied to compare the effects of different types of processing additives on the structure and properties of styrene-butadiene rubber/silica composites.The results showed that processing aids can effectively reduce the storage modulus and compound torque,and improve the processing properties of the rubber compound.In addition,the rubber compound with linoleic acid has better processing performance and filler dispersion status.However,the crosslink density of the vulcanizate was slight decreased,which will impair the physical and mechanical properties of rubber products.（2）In order to overcome the deficiencies of reinforcement and the migration problem of traditional processing additives,and modify the surface characteristics of silica,the environmentally-friendly processing additive SiO2-s-OA was firstly prepared by using filler-support method.The structure and composition of the modified filler were characterized,and structure and properties of the styrene-butadiene rubber composites were also systematically analyzed.The results show that SiO2-s-OA can effectively improve the processing performance of the rubber compound,and also overcome the shortcomings of the traditional processing additive.Compared with the coupling agent modified silica（m-SiO2）,SiO2-s-OA has a better dispersion state in SBR,stronger binding to rubber molecular chains,higher crosslinking density of composite materials,and stronger mechanical properties.Dynamic mechanical properties analysis shows that SBR/SiO2-s-OA can reduce the rolling resistance of styrene-butadiene rubber composites and effectively improve the wet skid resistance.（3）In order to further study the influence of the reactivity of processing additives on the properties of rubber composites,three different reactive fatty acid processing additives,stearic acid（SA）,oleic acid（OA）,and linoleic acid（LA）were used to prepare environmentally-friendly supported rubber processing additives:SiO2-s-SA,SiO2-s-OA,SiO2-s-LA.Compared with saturated SiO2-s-SA,unsaturated SiO2-s-OA and SiO2-s-LA can effectively improve the dispersion state of the filler,reduce the payne effect of the rubber compound,and improve the processing performance.Since both of them can participate in the vulcanization crosslinking reaction of styrene-butadiene rubber,the filler-rubber interface can be further enhanced to improve the physical and mechanical properties of the composite.Compared with SBR/SiO2-s-OA,SBR/SiO2-s-LA with higher degree of unsaturation has higher bound molecular layer fraction,and the stronger interface interaction between silica and SBR,and superior mechanical properties. |
