MIXED DIMERIZATION OF LIVING POLYMERS HAVING LI+ COUNTERIONS - KINETICS OF ADDITION OF 1,1-DIPHENYLETHYLENE TO LIVING LITHIUM POLYSTYRENE IN BENZENE

Kinetic studies of the addition of 1,1-diphenylethylene (D) to living lithium polystyrene not [fotmula-ommited]) in benzene demonstrated that the reaction is first order in the olefin (D). For an excess of D the rate of conversion of not [fotmula-ommited] into not [fotmula-ommited] is proportional to the unconverted not [fotmula-ommited], but the apparent rate constant is invertially proportional to [not [fotmula-ommited]][fotmula-ommited]. Denoting by/the ratio[fotmula-ommited] one finds df/dt = const • ([D]/[not [fotmula-ommited]f. Analysis of this result indicates that the following reversible reactions, 2[fotmula-ommited] [fotmula-ommited], 1/2K1; [fotmula-ommited] ↔ [fotmula-ommited], [fotmula-ommited], K12; and 2[fotmula-ommited] ↔ [fotmula-ommited], [fotmula-ommited], maintain minute equilibrium concentrations of the unassociated [fotmula-ommited] and [fotmula-ommited]. The former reacts with D in a bimolecular fashion, [fotmula-ommited] and the observed kinetics is then accounted for if K122 =K1K2. © 1969, American Chemical Society. All rights reserved.