Fluorescence and viscometry studies of poly(4-hydroxystyrene) in solution

Abstract

Fluorescence and viscosity of dilute solution of poly(4-hydroxystyrene) (PHS) were measured in methanol in the temperature range 5 to 55ŶC. The fluorescence spectrum of PHS showed two emission bands at around 308 nm and 356 nm, corresponding to the monomer and the excimer bands, respectively. From the temperature-dependent fluorescence measurements, a plot of the excimer to monomer intensity ratio Id/Im versus temperature was obtained, which shows double lines with positive slopes crossing at ca. 35ŶC. From temperature-dependent viscosity measurements, a plot of the limiting viscosity number [॑] versus temperature was obtained, which shows double lines with negative slopes crossing at ca. 40ŶC, above which the slope was decreased. These results indicate that there is stronger solvation of solvent molecules to polymer coil at temperatures below ca. 35舑40ŶC, arising from hydrogen bond formation between PHS and methanol molecules. © 1993, The Society of Polymer Science, Japan. All rights reserved.