The Application Research Of Cerium Oxide In Natural Rubber

In this dissertation, cerium oxide reinforced Rubber with good properties was prepared by means of mill-mixing in solid state, with Natural Rubber used as substrate and modified CeO₂ as the reinforce agent.The surface modification process of CeO₂ Power by stearic acid was investigated in this paper. The modified effects were evaluated by the surface properties such as particle size, TEM, FT-IR and DTA. The result shows that after the super-fine CeO₂ is modified by the stearic acid, the particle size of CeO₂ decreased, and the aggregation status of CeO₂ particulates significantly reduce. The stearic acid molecules adsorb bonding in cerium oxide surface. Part of the stearic acid molecules takes place chemical reaction with the ultra-fine cerium oxide surface, which leads to the formation of stearic acid salt. The DTA showed that a carbonization came into being on the CeO₂ surface at 500℃.The function of CeO₂ powder in natural rubber was investigated. On the other hand, the effects of particle size, content and surface modification of CeO₂ powder on the properties of natural rubber were discussed. The results showed that the tensile strength, stress at 200% elongation, abrasion resistance, tear strength and aging resistance of natural rubber vulcanizates enhanced in varying degrees after filled with the CeO₂ powder. Therefore, the curing time of rubbers will decrease 16% inadequate scorch time.SEM analysis indicates that the surface of modified CeO₂ powder had hydrophobic organise layer which could increase interface cohesion with the rubber and dispersity in the rubber resulting in exerting reinforcement effect. Combination Ce elements of rubber was found in vulcanizates after aging. XRD analysis indicates that CeO₂ accelerated crystallization capacity and confined the rubber chain movement. SEM was utilized to examine composite microstructures and worn surface. The result shows that the wear mechanism could be mainly concluding as: abrasive wear. The continuity of ridge fringe is cut off in worn surface of vulcanization, because of the existence of CeO₂, and the wear resistance of rubber is increased.