study of ethylene polymerization kinetics by ticl4/mg(oc2h5)2 catalyst and determination of the active sites concentration

نویسندگان

شکوفه حکیم

محمدمهدی مرتضوی

چکیده

ethylene was polymerized in slurry phase over a ticl4/mg(oc2h5)2 catalyst activated by al(c2h5)3. it was shown experimentally that mass transfer resistance has no effect on polymerization kinetics. after estimation ofthe active site concentration by inhibition method with carbon monoxide, the effects of polymerization temperature, monomer and cocatalyst  oncentrations and hydrogen were investigated. by determination of the average rate of polymerization at 13 min and 50 min of reaction times it was observed that the polymerization rate was first order with respect to the monomer concentration and the dependence of the polymerization rate on the concentration of al(c2h5)3 could be described by the langmuir-hinshelwood mechanism. the polymerization rate decreased with the increase of hydrogen partial pressure. polymerization rate as a function of polymerization temperature showed a maximum point.

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عنوان ژورنال:
علوم و تکنولوژی پلیمر

جلد ۲۱، شماره ۶، صفحات ۵۱۵-۵۲۲

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