INTERACTIONS BETWEEN SODIUM DODECYL-SULFATE AND HYDROPHOBICALLY-MODIFIED POLY(ACRYLAMIDE)S STUDIED BY ELECTRON-SPIN-RESONANCE AND TRANSMISSION ELECTRON-MICROSCOPY

The interactions of hydrophobically modified poly(acrylamide)s (HMPAM) and unmodified poly(acrylamide) (PAM) with sodium dodecyl sulfate (SD S) have been studied by electron spin resonance using 2,2,6,6-tetramet hylpiperidine-1-oxyl and 4-oxo-2,2,6,6-tetramethylpiperidine-1-oxyl as spin probes. The morphologies of dried solutions of the polymers with and without SDS have also been observed by transmission electron micr oscopy. The rotational correlation time tau(c), of the spin probes ref lects the microenvironment of the polymer-micelle aggregates, which in dicates that the higher hydrophobicity of HMPAMs leads to a much more compact packing in the polymer-micelle aggregates. The interactions be tween surfactants and polymers cause morphological transitions of poly mers, which results in the polymer chains stretching out.