Multifunctional initiator for obtaining anionically star polymers process for its production and corresponding star polymers, process for their production and their use

摘要

A multifunctional initiator for anionic polymerisation, soluble in a polar media and (almost) free from residual C=C bonds, is of formula (I), where PA = polymer sequence derived from a monomer (A) comprising a vinyl-aromatic or dienyl monomer; a = 3-30 (3-15) and is the number of branches of PA; N = a cross-linked nodule (almost) free from residual C=C bonds, of formula (PMr)(RLi)p (II); Mr = monomer with at least 2 polymerisable C=C bonds; PMr = cross-linked nodule from at least one Mr monomer and contg. 3-30% of residual C=C bonds, w.r.t the initial C=C bonds from Mr; R = 1-6C alkyl, (substd.) aryl with 1 or more rings, arylalkyl or alkylaryl where the alkyl is 1-6C, cycloalkyl, or 2-6C alkenyl substd. with aryl or alkylaryl; p = number of residual C=C bonds of PMr neutralised by RLi; n = number of anionic sites in N and = a+p'; and p' = number of anionic sites in the cross-linked nodule PMr before addn. of RLi. Pref. in (I) A = styrene, butadiene or isoprene; Mr = divinylbenzene; RLi = sec.- or n-butyl Li, alpha -methyl-styryl-Li, 1,1-diphenyl- hexyl-Li, diphenylmethyl-Li or 1,1-diphenyl-3-methylpentyl-Li. The initiator has mol. wt. of 2500-500,000, and Mw of one PA branch of at least 500-200,000. The initiator is in soln. in toluene, benzene, and/or ethylbenzene, as a polar medium, opt. with a minor amt. of (cyclo)hexane or heptane.