What advantage does ethylene propylene rubber with three yuan compare to two yuan ethylene propylene rubber?
Because the two EPDM molecules containing double bonds, not curing, which limits its application. In the ethylene propylene rubber commodity brand, two yuan ethylene propylene rubber accounts for only about 10% of the total. While the three rubber vulcanization available, which has been widely used, and become the main varieties of ethylene propylene rubber, ethylene propylene rubber in the commodity brands accounted for about 90%. At present, third monomers commonly used in the industrial production of three yuan ethylene propylene diene monomer are ethylene glycol norbornene (ENB), dicyclopentadiene (DCPD) and 1, 4- (HD).
In recent years, the third monomer and new technology development, foreign developed 1 7- octadienoic, 6, 5, two 10- methyl -1, 9- eleven, 7- two three ene 3, methyl -1, 6- octadienoic, 5 7-, two methyl -1, 6- octadienoic, 7- methyl -1, 6- octadiene as the three EPDM third monomer, the performance of three Yuan rubber has been enhanced. The monomer and content of third monomer in three yuan ethylene propylene rubber have direct influence on vulcanization rate and vulcanizate property. Among them, dicyclopentadiene (DCPD) as the third monomer, although the price is low, but the three Yuan rubber vulcanization speed is slow, difficult and high degree of unsaturation diene rubber and use; to ethyiidenenorbomene (ENB), 6 10-, two methyl -1, 5, third monomer three Yuan rubber vulcanization speed 9- eleven three ene as fast, the former has become the main varieties of three yuan of ethylene propylene rubber. The third monomer content in iodine said three EPDM iodine value is generally 6-30, mostly around 15. The iodine value is 6-10, curing speed is slow, difficult and high unsaturated rubber; iodine value is 25-30, for ultra high speed curing type, available in any proportion and high unsaturated diene rubber and use. Therefore, three yuan ethylene propylene rubber and other rubber in use, should pay attention to choose the appropriate three yuan ethylene propylene rubber varieties.
Propylene rubber can be divided into two yuan ethylene propylene, three yuan ethylene propylene, modified ethylene propylene and thermoplastic ethylene propylene. Ethylene propylene rubber in olefin copolymerization of ethylene and propylene as binary ethylene propylene rubber; prepared three EPDM with ethylene, propylene and a small amount of non conjugated diene monomer copolymerization. The molecular chain of ethylene propylene rubber, ethylene and propylene monomer showed irregular arrangement, lost the regularity of polyethylene or polypropylene structure, thus becoming the elastomer, because three EPDM diene in the side chain, so the three rubber can be used not only sulfur curing also maintained, various characteristics of two yuan rubber.
