The reaction between carbon monoxide and the Ti-polyethylene bond was investigated using a stopped-flow (short-time) polymerization method which provides quasi-living polymers with very low molecular weights. Ethylene polymerization was conducted with a typical homogeneous Cp2TiC12-methylaluminoxane catalyst. The Ti-terminated polymers were introduced into toluene saturated with carbon monoxide or containing laC-enriched carbon monoxide at -78°C. The mixture was gradually heated up to room temperature, and a small portion of the reaction mixture was taken out at - 78°C, 0°C and room temperature to analyse the structure of each polymer by FTi.r., gel permeation chromatography, 1H n.m.r, and 13C n.m.r. It was found from these analyses that carbon monoxide is incorporated into the polymer mainly as a ketone carbonyl.
Посилання на статтю:
Reaction of the Ti-polyethylene bond with carbon monoxide over the bis ( cycl opentad ienyl )tita n i u m dichloride-methylaluminoxane catalyst system / Takeshi Shiono, Masaaki Ohgizawat and Kazuo Soga // Polymer. – 1994. – Vol 35. – P. 187-192.