ANGEWANDTE MAKROMOLEKULARE CHEMIE, vol.200, pp.37-47, 1992 (SCI-Expanded)
Tetrafunctional initiators T4-AZO4, T4-TCE1 and T4-IPDI4 have been synthesized by using insertion reaction of tetrakis(dimethylamino)-titanium (T4) with 2,2'-azoiso-butyronitrile (AIBN), tetracyanoethylene (TCE) or isophorone diisocyanate (IPDI), respectively, in dry benzene under nitrogen at 35-degrees-C. T4-AZO4 is useful for preparing four-branch polymers from radically polymerizable monomers by decompositon of the azo groups incorporated in the related initiator. Four-branch polyacrylonitrile can be synthesized by using the initiator T4-TCE1. This initiator possesses titanium-amino functionalities which are capable of initiating acrylonitrile polymerizations. The tetrafunctional isocyanate compound T4-IPDI4 is found to be useful to prepare a model network of dihydroxy-terminated polymers.