STEREOSPECIFIC POLYMERIZATION OF BUTENE-1 WITH SUPPORTED TITANIUM CATALYST

Butene-1 was polymerized with a highly-active supported titanium catal yst which was developed in this laboratory. The influences of various conditions (e.g., catalyst composition, temperature, external ester, H -2, triethylaluminum, and catalyst concentration) on the catalytic act ivity, decay of polymerization rate, molecular weight, and isotacticit y of the products were studied in detail. The structural properties of the PB- 1 were characterized by WAXD, DSC, and C-13-NMR. It was found that the catalyst TiCl4, Ti (OBu)4 / MgCl2/ ethyl benzoate (EB)/Ph2Si Cl2-AlEt3 shows high activity, i.e., 3.2 X 104 g PB/g Ti h. Isotactici ty of the product was increased by adding p -CH3C6H4COOEt into the cat alytic system. Molecular weight of the product can be easily controlle d by H-2. The decay of polymerization rate with time fulfills the equa tion: R(t) - R(s) = (R0 - R(s)) e(-betat). (C) 1993 John Wiley & Sons, Inc.