The Basic Properties Of The Vulcanized Rubber Powder Were Characterized And Their Modified Rubber Powder And Study

In this paper, the waste rubber power modification was studied, the product of which can be used as rubber resource. It is supposed to be one of the most potential ways to produce fine waste rubber powder. It is a blend of raw rubber, which could effectively avoid secondary pollution as much as possible. However, there are still several problems such as the unfamiliar shape of the starting materials and the low performances of the obtained blends. To overcome these problems, taking the waste rubber powder as the targets, physical properties was studied such as powder sizes and size distributions, surface morphologies and compositions as well as oxide contents in the surface have been systematically analyzed. Based on these, the effects of such factors on the obtained samples prepared by using pure waste rubber powder have been discussed. Moreover, to improve the whole performance of the product samples, the chemical activation and extrusion methods have been employed and their effects on the product rubber samples have been clarified. Blending with natural rubber or styrene butadiene rubber as the matrix, the relationships between their compositions and technological conditions and the properties of the obtained blends have been studied to improve their mechanical properties further.The rubber powder, vulcanized rubber, rubber powder modification and the properties of blend rubber was studied. As a result, we can draw some conclusions that:1. The rubber powder which was produced by grinding method at room temperature was mainly composed of natural rubber, styrene butadiene rubber, carbon black and other chelating agent composition. The200mesh narrow size distribution powder, mainly in the40-85μm with an average particle size of66.61μm, and the specific surface area of33.81m/kg. The SEM analysis showed that the surface is irregular and has numerous glitches state bumps. The basic composition of vulcanized rubber powder is:rubber hydrocarbon51%, carbon black26%, ash8%, acetone extract14%, heating loss0.8%and iron0.03%. Surface oxygen groups of80mesh acid is118, and carbonyl value is2.68mmol·(100g)-1. Compared to the entire tire, the rubber powder made from tire tread showed better performance, with the tensile strength increasing2MPa, elongation rate increasing40%. The smaller size of the rubber powder, the better properties of the vulcanizates can be obtained. Compared to40mesh powders, the tensile strength and elongation of vulcanizates made of100mesh powder had increased by2MPa and30%respectively. 2. SEM analysis showed the active agent was adsorbed or coated on the powder surface after surfaces activate modification of vulcanized rubber powder. From the rubber powder and activation of crumb mechanical properties of vulcanizates, it showed that the activate modification of plasticizing and refining performances was improved. The time of activation process2decreased from is6’01" to5’31" after modification, and Mooney viscosity[ML(1+4)100℃] increased from6.53to21.22. The fracture elongation compared to the unmodified rubber powder vulcanizates increased by37%. In general, vulcanized rubber powder modified by activation of modification process2had better performance. Through the rubber powder and the rubber powder modified blend with the preparation of raw rubber, it can be seen that the rubber powder of activate modified vulcanizates filled with physical and mechanical properties are significantly better than untreated vulcanizates. The tensile strength unmodified system is18.46MPa. At the same time, the activation of the modified reached to24.97MPa, the fracture elongation increased from522.32%to572.99%. Especially in the system of SBR for the matrix, the tensile strength of vulcanized rubber modified of activation vulcanizates is16.81MPa, and the pure SBR is18.18MPa. The fracture elongation and tear strength are both higher than pure SBR vulcanizates, respectively555.13%,36.46kN/m, while the pure SBR is513.3%,35.54kN/m, and the Mooney viscosity [ML(1+4)100℃]17.35closer to the pure SBR22.94.3. Regeneration of vulcanized rubber powder modified by extrusion can form a dense surface of the block reclaimed rubber powder, increasing surface active groups. Mechanical properties of vulcanizates by extrusion were improved with plasticity0.33, unmodified0.04, Mooney viscosity[ML(1+4)100℃]97.43, unmodified6.53, and the processing performance has improved significantly. By comparing the mechanical properties of rubber powder got from four different modification processes, process1and2result in the best performance. The blend rubber of powder reclaimed rubber and natural rubber, the tear strength and elongation are better than pure natural rubber,668.2%and85.56kN/m, while natural rubber are572.99%and70.47kN/m, the blend rubber of powder reclaimed rubber and SBR. The tensile strength, fracture elongation and tear strength are higher than pure SBR, respectively19.37MPa,669.09%,51.90kN/m Pure SBR for18.18MPa,513.3%,35.54kN/m. The performance of extrusion recycled were better than the activation modified, both the physical and mechanical properties were improved. So the rubber products which doped of a large number of the reclaimed rubber powder can be used.