chapter  14
16 Pages

Microheterogeneous Titanium Ziegler Natta Catalysts: The Influence of Particle Size on the Isoprene Polymerization

Abstract ................................................................................................. 158 14.1 Introduction .................................................................................. 158 14.2 Experimental Part ........................................................................ 159 14.3 Results .......................................................................................... 161 14.4 Discussion .................................................................................... 169 14.5 Conclusion ................................................................................... 170 Acknowledgments ................................................................................. 171 Keywords .............................................................................................. 171 References ............................................................................................. 171

ABSTRACT

The effect particle size of microheterogenous catalyst TiCl4−Al(iso�C4H9)3 on the basic patterns of isoprene polymerization is studied. Fraction of particles with a certain size isolated from the mixture of particles, which is formed by reacting the initial components of the catalyst and its following exposition. The most active in isoprene polymerization is particles fraction with starting dia�eter of 0.7−4.5 μ�. In these particles preferably localized highly active polymerization site. Doping diphenyloxide and piperylene, lower exposition temperature, hydrodynamic actions in turbulent flows result in formation of nearly mono disperse catalyst with dia�eter of 0.15−0.18 μ�. In this case there is a shift in activity spectru� of polymerization sites towards formation of single site with high activity. PACS: 82.65+r, 82.35-x.