| 摘要 |
A process for the production of EPDM comprising reacting ethylene, propylene, ethylidene norbornene, and hydrogen, in the gas phase, in a fluidized bed, under polymerization conditions, in the presence of a catalyst system comprising: (a) a titanium based catalyst having the formula MgaTi(OR)bXc(ED)d wherein R is an aliphatic or aromatic hydrocarbon radical having 1 to 14 carbon atoms or COR min wherein R min is an aliphatic or aromatic hydrocarbon radical having 1 to 14 carbon atoms; each OR group is alike or different; each X is independently chlorine, bromine, or iodine ED is an electron donor a is 0.5 to 56; b is 0, 1, or 2; c is 2 to 116; and d is greater than 1.5 a + 2; (b) at least one modifier having the formula BX3 or AlR(3-b)Xb wherein each R is alkyl or aryl and is alike or different, and X and b are as defined above for component (a), wherein components (a) and (b) are impregnated into an inorganic support; and (c) a hydrocarbyl aluminum cocatalyst with the following proviso: (i) the partial pressure of ethylene is in the range of about 10 to about 150 psi; (ii) the molar ratio of propylene to ethylene is in the range of about 1.5:1 to about 5:1; (iii) the molar ratio of hydrogen to ethylene is in the range of about 0.001:1 to about 0.1:1; and (iv) the amount of ethylidene norbornene is about 1.5 to about 15 percent by weight based on the weight of the fluidized bed. |
