LITHIUM AMINOMAGNESIATE POLYMERIZATION INITIATOR AND ELASTOMER SHOWING LOWERED HYSTERESIS

摘要

PROBLEM TO BE SOLVED: To obtain a polymerization initiator which is stable at high temperatures and promotes the incorporation of derived functional tert. amine groups in a polymer chain by using a specified lithium aminomagnesiate complex. SOLUTION: An organolithium compound of the formula: R1 Li is reacted with a magnesium bicyclic amide of the formula: A2 Mg to obtain an anionic polymerization initiator containing a lithium aminomagnesiate complex being a reaction product of the formula Ax Mg(R1 )3-x Li [wherein A is a cyclic amine substituent of the formula; (x)is 2 or 3; when x=2, the organolithium compound is a 1-20 C alkyl, cycloalkyl, alkenyl, alkinyl, aryl or aralkyl-lithium; when x=3, this compound is A-lithium, provided that the substituents A are the same or different substituents; R2 is a chain of 3-20 methylene groups; R3 is a 1-20C alkyl or cycloalkyl or the like; and (y) is 0-10]. A polymer derived from this polymerization initiator is obtained before quenching, and a vulcanizable elastomer composition is formed from the polymer and carbon black.