Halosilyl-substituted Cyclopentadienyl Titanium Complexes as Catalysts for Styrene Syndiospecific Polymerisation

článek v časopise - ostatní, Jost

angličtina

Syndiotactic polystyrene is an interesting material with a high melting point of 275 degree C and a fast crystallization rate as compared with isotactic polymer. Its interesting properties which are similar to those of some more expensive engineering plastics are the reason for further scientific interest. In our previous work we reported the catalytic behaviour of novel half-sandwich titanium complexes; [TiCl3(C5H4SiCl3)], [TiCl3(C5H4SiMe2F)], [TiCl3(C5H4SiMeF2)], [TiCl3(C5H4SiF3)] and [TiF3(C5H4SiMe2F)] in syndiotactic styrene polymerisation. The variation of halosilyl substitutent on cyclopentadienyl ligand affected both the catalytic activity and the properties of s-PS. In this contribution a series of polymerisation runs was carried out in a time scale of 20-120 min in order to compare the activity dependence of examined complexes on reaction time and thus to better evaluate their polymerisation behaviour. Results obtained are discussed with respect to the steric and electronic properties of ligand sphere influencing significantly the character of active species.

polystyrene, titanium complex

HERMANOVÁ, S.; MERNA, J.; ERBEN, M.; SVAČINA, Z.

2008

9. 9. 2008

1213-7103

Chemické listy

102

15

Česká republika

s1243

s1244

2