Polymer and Materials Science
Wiley InterScience Backfile Collection 1832-2000
Chemistry and Pharmacology
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Slurry polymerization of propene using MgCl2-supported TiCl4/dioctylphthalate catalysts were carried out in a semibatch reactor at a constant pressure to examine the effects of polymerization conditions on catalyst activity and polymer isotacticity. The catalysts were prepared at 80, 90, and 105°C, which gave different compositions of chemical complexes associated with the diester. Five alkyl aluminums (triethyl, triisobutyl, tri-n-hexyl, tri-n-octyl, and isoprenyl) were studied as cocatalysts. Among these, triethyl aluminum was found to be most effective for the catalysts prepared at 80 and 95°C, and tri-n-hexyl aluminum for the catalyst prepared at 105°C. Dimethoxydiphenyl silane and 2,2,6,6-tetramethylpiperidine were employed to study their effects as an external Lewis base for the catalyst prepared at 105°C. In both cases, a small amount of either base resulted in significant increase in activity and isotacticity, which can be attributed to the high level of phthaloyl chloride complex in the catalyst. © 1995 John Wiley & Sons, Inc.
Type of Medium: