study of ziegler-natta/(2-phind)2zrcl2 hybrid catalysts performance in slurry propylene polymerization
نویسندگان
چکیده
several types of hybrid catalysts are made through mixing of 4th generation ziegler-natta (zn) and (2-phind)2zrcl2metallocene catalysts using triethylaluminum (tea) as coupling agent. response surface methodology (rsm)is used to evaluate the interactive effects of different parameters including amounts of metallocene and tea andtemperature on metallocene loading. analyzing the amounts of al and zr elements in the hybrid catalysts throughicp-oes and edxa reveals that temperature plays a crucial role on anchoring of the metallocene catalyst on znwhile tea has the least determining effect. the icp analysis shows that as the concentration of al goes up in thehybrid catalyst the concentration of zr passes a maximum, while edxa shows a direct relationship between the aland zr contents. using triisobutylaluminum (tiba) and methylaluminoxane (mao) as the coupling agents, almostsimilar metallocene loadings are observed. finally, the performance of hybrid catalysts is investigated in propylenepolymerization and the obtained polymers are characterized using dsc and dmta through which the presence of twotypes of polymers in the final product are confirmed.
منابع مشابه
Study of Ziegler-Natta/(2-PhInd)2ZrCl2 hybrid catalysts performance in slurry propylene polymerization
Several types of hybrid catalysts are made through mixing of 4th generation Ziegler-Natta (ZN) and (2-PhInd)2ZrCl2 metallocene catalysts using triethylaluminum (TEA) as coupling agent. Response surface methodology (RSM) is used to evaluate the interactive effects of different parameters including amounts of metallocene and TEA and temperature on metallocene loading. Analyzing the amounts of Al...
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عنوان ژورنال:
polyolefins journalISSN 2322-2212
دوره 2
شماره 2 2015
میزبانی شده توسط پلتفرم ابری doprax.com
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