Study of Ziegler-Natta/(2-PhInd)2ZrCl2 hybrid catalystsperformance in slurry propylene polymerization

Smetallocene catalysts using triethylaluminum (TEA) as coupling agent. Response surface methodology (RSM) everal types of hybrid catalysts are made through mixing of 4th generation Ziegler-Natta (ZN) and (2-PhInd)2ZrCl2is 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 fnal product are confrmed. Polyolefns J (2015) 2: 73-87

کلیدواژه ها:

Hybrid catalysts ، Ziegler-Natta ، metallocene ، surface analysis ، bulk analysis ، polypropylene