FLUORESCENCE STUDY OF THE KINETICS OF ALKALI COUNTERION TRANSFER FROMA CARBOXYLIC IONOMER TO A POLYMER CARRYING SULFONIC-ACID SUBSTITUENTS

Copolymers of butyl methacrylate (BMA) with 3-(methacryloylamino)-2-na phthoic acid (MANA) were neutralized with lithium methoxide, sodium me thoxide, and cesium hydroxide. The counterion transfer from these copo lymers to a BMA copolymer with [(2-(acryloylamino)prop-2-yl]methanesul fonic acid (APMS) was monitored by the fluorescence change in a stoppe d-flow apparatus in which solutions with equivalent concentrations of MANA and APMS residues were mixed. The half-life of this transport was 17 times smaller in dioxane than in toluene and increased with a decr easing size of the counterion. The apparent rate constant increased wi th the progress of the ion transfer, which was interpreted as due tb a decreasing ion-pair dimerization. The half-life of the process decrea sed much more rapidly with an increasing concentration of the interact ing copolymers than expected for second-order kinetics. Addition of po ly(butyl methacrylate) had no significant effect on the rate of counte rion transfer from BMA/MANA to the BMA/APMS copolymer.