metal salts of saturated aliphatic alcohols can be used as modifiers in lithium initiated solution polymerizations of diene monomers into rubbery polymers . sodium t - amylate is a preferred modifiers because of its exceptional solubility in non - polar aliphatic hydrocarbon solvents that are employed as the medium for such solution polymerizations . however , using sodium t - amylate as the polymerization modifier in commercial operations where recycle is required can lead to certain problems . these problems arise due to the fact that sodium t - amylate reacts with water to form t - amyl alcohol during steam stripping in the polymer finishing step . since t - amyl alcohol forms an azeotrope with hexane , it co - distills with hexane and thus contaminates the feed stream . the present invention solves the problem of recycle stream contamination . this invention is based upon the discovery of highly effective modifiers that do not co - distill with hexane or - form - compounds during steam stripping which co - distill with hexane . the modifiers of this invention are metal salts of cyclic alcohols . since the boiling points of these metal salts of cyclic alcohols are very high , they do not co - distill with hexane and contaminate recycle streams . additionally , metal salts of cyclic alcohols are considered to be environmentally safe . the , subject invention more specifically discloses an initiator system which is comprised of a lithium initiator , a metal salt of a cyclic alcohol , and a polar modifier .