Mechanical Properties Of Diatomite/carbon Black Filled Rubber Composites

Pure rubber usually needs to add various fillers and auxiliaries to reinforce and functionalize to meet application requirements.Carbon black is the most widely used rubber reinforcing filler,but the role of carbon black in rubber also has certain limitations,such as Filler heat,wear and other properties need to be improved.Recent studies have shown that the addition of diatomite material containing pore structure to rubber can effectively reduce the heat generated by rubber filling,but the reinforcing effect of diatomite is not yet clear.In this paper,based on the analysis of the physicochemical structure of diatomite particles,the mechanical properties of diatomite/carbon black dual-phase filler filled rubber composites were studied.The physical and chemical structures of diatomite particles were characterized by XRD,XPS,SEM and TEM.The results showed that diatomite particles had a high specific surface area and pore structure,and the main component was silica(Si O2).A large amount of Si-OH is present on the surface of the particles,which is also an important reason for causing diatomite agglomeration.Different proportions of rubber composites were prepared,and the reinforcing mechanism of diatomite particles was studied through quasi-static and dynamic mechanical properties tests.Through the calculation of the cohesive energy between the filler networks,combined with the discussion of the Payne effect of the improved CCA model,the effect of diatomite particles on the filler network structure was analyzed.It shows that filling a small amount of diatomite filler can make the carbon black filler network more stable,and filling too much diatomite filler will destroy the structure of the carbon black filler network and lead to a decrease in the reinforcing effect.The finite element method was used to analyze the filled rubber representative volume unit(RVE)model.By setting up a single-phase particle-filled RVE model,the influence of filler particle parameters and pore structure on the material properties was explored,and a possible type of pore structure may arise.Negative pressure adsorption was discussed.The RVE model of diatomite/carbon black dualphase filler filled rubber composites was further established.The effect of diatomite on the mechanical properties of the fillers was analyzed,and a "double x-type" filler network model was proposed for its reinforcement.The mechanism was analyzed.Through the dynamic mechanical properties test,Payne effect analysis of the filler network,and the numerical simulation study of the mechanical properties ofthe particle-filled material,the action mechanism of the diatomite-reinforced rubber obtained provides a basis for the development of a new type of filler.