摘要 |
Very desirable polyfunctional lithium containing polymerization initiators are prepared by reacting an adduct of an organo lithium compound and styrene with an organic compound containing at least two 1,1-diphenylethylene groups in the proportion of about two moles of the adduct to one mole of the organic compound. A difunctional lithium initiator is prepared thereby. The difunctional initiator may be reacted with styrene and subsequently an additional quantity of the diphenylethylene compound which in turn is reacted with the styrene-organo lithium adduct to form a trifunctional initiator. The process can be repeated to obtain an initiator having any desired degree of lithium functionality. Such initiators can be prepared in the absence of polar solvents and are very desirable for the polymerization of dienes such as butadiene to a desirable 1,4 configuration and preparation of block copolymers.
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