A Study on the Selectivity of Toluene/Ethanol Mixtures on the Micellar and Ordered Structures of Poly(styrene-b-4-vinylpyridine) Using Small-angle X-ray Scattering, Generalized Indirect Fourier Transform, and Transmission Electron Microscopy

The effects of the selectivity of toluene/ethanol mixtures on the micellar and ordered structures of PS(12K)-b-P4VP(11.8K) in the dilute, semidilute, and concentrate solutions, as well as in the solid state, were studied using small-angle X-ray scattering (SAXS), generalized indirect Fourier transform (GIFT), and transmission electron microscopy (TEM) methods. For the dilute solutions (1 wt %), only form factors were observed in SAXS at φ (weight percent of ethanol in the ethanol/toluene mixture) = 0 to 20 and 70 to 100 (selective solvents), while isotropic states were found at other solvent mixture ratios (nonselective solvents). Hard and large spherical micelles were formed in high-selective solvent mixtures while soft and small ones were formed in less-selective solvent mixtures. For the semidilute solution (8 wt %), both of structure and form factors of SAXS curves appeared in selective solvents while isotropic states were also observed in nonselective solvents. The form factors that were separated by...