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This study describes the effect of salt on the aqueous solution property of the anionic terpolymer (SPM/NIPAM/PyMMA) of potassium-2-sulfopropylmethacrylate (SPM), N-isopropylacrylamide (NIPAM), and 1-pyrenemethylmethacrylate (PyMMA) in terms of fluorescence and dynamic light scattering. A plot of the thermally induced changes in I1/I3 and IE/IM ratios for pyrene-labeled SPM/NIPAM/PyMMA with various temperatures was showed. IE/IM value (the ratio of intensities of the excimer and the monomer fluorescence emission) of SPM/NIPAM/PyMMA, which reflects the interactions of pyrene groups and the probability of dimeric pyrene, was investigated. The ratio of intensity of the first to the third vibronic bands (I1/I3) in the fluorescence spectra of pyrene-labeled SPM/NIPAM/PyMMA depends on the polarity in the media, where pyrene exists. The IE/IM value of anionic terpolymer in aqueous solution varied with various surfactant (SDS) concentrations. Hydrodynamic diameters of anionic SPM/NIPAM/PyMMA in aqueous solution were also measured with various surfactant (SDS) concentrations. The same trends were obtained in fluorescence and dynamic light scattering measurements. At the lowered pH, the protonation of anionic terpolymer enhances hydrophobic association of polymer chains. The I1/I3 ratio decreases with increasing temperature, but the IE/IM ratio increases. |
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