A new stereoregular polybutene-1 was synthesized with a novel catalyst precursor η5-pentamethyl cyclopentadienyl titanium tribenzyloxide (Cp*Ti(OBz)3) and methylaluminoxane (MAO). The effects of polymerization conditions on the catalytic activity, molecular weight and stereoregularity of the products were investigated in detail. It was found the catalyst exhibited highest activity of 91.2kgPB mol Ti-1h-1 at T = 30°C, Al/Ti = 200. The catalytic activity and molecular weight were sensitive to the Al/Ti (mole/mole), polymerization temperature; they also depended on the Ti concentration. The molecular weight of the products increased with decreasing temperature. The structure and properties of the polybutene-1 were characterized by 13C NMR, GPC, DSC and WAXD. The result showed the microstructure of polybutene-1 extracted by boiling heptane was stereoregular, whereas the ether-soluble fraction was atactic. The molecular weight of polybutene-1 was over one million g mol-1 and its molecular weight distribution (M̄w/M̄n) was from 1.1 to 1.2.
|Number of pages||4|
|Publication status||Published - 6 Mar 2001|
- Half-Metallocene catalyst
- Narrow disperse