REGULAR COMB POLYSTYRENES AND GRAFT POLYISOPRENE POLYSTYRENE COPOLYMERS WITH DOUBLE BRANCHES (CENTIPEDES) - QUALITY OF ENYLENE)BIS(3-METHYL-1-PHENYLPENTYLIDENE)DILITHIUM INITIATOR IN THE PRESENCE OF POLAR ADDITIVES/

The synthesis of regularly spaced comb polystyrenes and graft polyisop rene/polystyrene copolymers with two branches at each junction point ( centipedes) is presented. The synthetic approach involves the selectiv e replacement of two chlorines of SiCl4 by polystyrene (PS) followed b y step-growth polymerization of the produced (PS)(2)SiCl2 with alpha,o mega-dilithium PS or 1,4 polyisoprene (PI). The polydispersity indices of the reaction products, PS-g-PS2 (homocentipedes) and PI-g-PS2 (coc entipedes), varied between 2.0 and 3.0 but was reduced to 1.2-1.3 by f ractionation. The quality of enylene)bis(3-methyl-1-phenylpentylidene) dilithium initiator (DLI), used for the synthesis of the dianion, in t he presence of polar additives (THF, Et3N, and s-BuOLi); was evaluated .