Cationic polymerization with titanium(iv) compounds: Living polymerization and possibility of stereoregulation

摘要

AbstractThis paper deals with the development of living cationic polymerizations and the possibility of stereoregulation therein based on the modulation of the Lewis acid activators by their ligands. For this, titanium(IV) chlorides TiCl4‐n(OR)n with various alkoxy or aryloxy groups were synthesized and employed for the cationic polymerizations of isobutyl vinyl ether (IBVE) in conjunction with HCl‐IBVE adduct. Living polymerizations were feasible with the titanium chlorides TiCl2(OR)2 disubstituted with isopropoxy or phenoxy groups in CH2Cl2at −15°C. Themeso(isotactic) contents of the polymers obtained with TiCl2(OR)2at −78°C became larger (up to 86) with bulkiero‐substituents of phenoxy groups on the titaniu