Study of Self-Diffusion of Molecules in Polymer Gel by Pulsed-Gradient Spin-Echo 1H NMR. 3. Stearyl Ιtaconamide/N,N-Dimethylacrylamide Copolymer Gels

Abstract

Intermolecular hydrophobic interactions between poly(ethylene glycol) oleyl ether (PEG-Ole) as probe polymer and network polymer in stearyl itaconamide (SIA)/N,N-dimethylacrylamide (DMAA) copolymer gel swollen with water, in which the micelle of SIA is immobilized by copolymerization, have been studied through the diffusion coefficient (D) determined by the pulsed-gradient spin-echo 1H NMR method with the field gradient strength of 22.3 T m-1 and 1H spin−lattice relaxation time (T1) and 1H spin−spin relaxation time (T2) by the 1H pulse NMR method. From these experimental results, it was found that in the diffusion process PEG-Ole in SIA/DMAA copolymer gel takes the mobile and immobile states, and 1H T2 of PEG-Ole in SIA/DMAA copolymer gel is shorter than that of PEG. This shows that the comicellization of PEG-Ole and SIA is induced by hydrophobic interaction between the oleyl group in PEG-Ole and the stearyl group in SIA. Furthermore, to elucidate kinetics of the incorporation of PEG-Ole into the micelle ...