Using a stopped-flow apparatus with fluorescence detection we followed
the expansion of poly(methacrylic acid) after a pH jump, the enhancem
ent of fluorescence of Auramine O after association with poly(methacry
lic acid), the counterion exchange in ionomer solutions and the depend
ence of the rate of inter-polymer reactions on the polymer chainlength
. Fluorescence was also used to follow the unfolding of collapsed chai
ns in bulk polymers and counterion diffusion in bulk ionomers.