Research Of Unsaturated Carboxylic Acid Metal Salts In The Cm And Cm/Epdm System

The zinc dimethacrylate (ZDMA) and magnesium methacrylate (MDMA) prepared by the laboratory were characterized. The effection of the amount of the unsaturated carboxylic acid metal salt, adding method, types of vulcanizing agent and types of aid-crosslinking agent on the mechanical properties, heat-air aging properties and the vulcanization characteristics of the rubber material, as well as on the crosslinked structure of the vulcanized rubber of CM and CM/EPDM were studied with the unsaturated carboxylic acid metal salt added by directly or in situ.The research results of the unsaturated carboxylic acid metal salt applied to CM showed that the curing speed rated, as well as the total crosslink density and the ionic crosslink density increased significantly with the amount of methylacrylic acid metal salt. Compared with that of MDMA and TAIC, the tensile strength, tensile modulus and hardness of the CM vulcanizates with addition of the same amount of ZDMA as crosslinking aids improved larger, but the anti-aging properties was poorer. As for DCP curing system with MDMA as aid-crosslinking agent, the best mechanical properties and heat-air aging properties of vulcanizates was obtained with2to4phr MDMA and more than1phr DCP. The perfect comprehensive properties of CM reinforced by MgO/MAA was obtained with30phr MDMA. On the other hand, the comprehensive properties of CM with ZDMA was better.The study of adding the methylacrylic acid metal salt to the CM/EPDM blend system showed that ZDMA displayed the better aid-crosslinking effect with comparision of MDMA and TAIC. The CM/EPDM vulcanizate with ZDMA prepared in situ, as the aid-crosslinking agent, occupied the best tensile strength and tear strength, as well as the minimum of tensile deformation at set; the vulcanizate with MgO/MAA aid-crosslinking system could keep high elongation at break, while the effect of Mg(OH)2/MAA was the worst. The vulcanization rate reached a maximum when the mole ratio of ZnO/MAA was0.75, as well as the mechanical properties were better. In comparision to that of CM/EPDM vulcanizates with adding methylacrylic acid metal salt directly, the tensile strength of CM/EPDM vulcanizates with ZDMA prepared in situ was better. The methylacrylate metal salt filled in the CM/EPDM system directly or in situ affected considerably when used as reinforcement.