FLUORESCENCE STUDY OF POLYELECTROLYTE COMPLEX-FORMATION .2. EFFECT OF ACIDITY OF POLYANIONS ON COMPLEXATION

Poly(sodium 2-acrylamido-2-methylpropanesulphonate) and poly(sodium p-styrenesulphonate) containing a small amount of anthryl groups (PAMPS-A and PSS-A, respectively) were prepared. Formation of polyelectrolyte complexes (PEC) of these polyanions with a series of polycations in aqueous solution was investigated by fluorescence techniques. The result was compared with that for the PEC of anthracene-loaded poly(methacrylic acid) (PMA-A). The fluorescence intensity of PAMPS-A sharply increased when an equimolar amount of polycations were added, suggesting the formation of 'stoichiometric' PECs. The fluorescence lifetimes also increased with complexation. The fluorescence spectra of the PECs with the polycations containing phenyl groups showed broad emission, whereas the PECs without phenyl groups sharpened their spectra. These observations allowed estimation of the anthryl chromophore location in the PEC microdomains.