STUDIES OF SOLUTION DYNAMICS OF POLY(N-VINYL PYRROLIDONE) AND ITS IODINE ADDUCT

Carbon-13 NMR spin-lattice relaxation times T//1 of poly(N-vinyl pyrrolidone) (PVP) and PVP-iodine have been studied in several solvents and at different temperatures. Three kinds of motion can be identified from the T//1 data: segmental motion, ring rotation, and ring puckering. The effective correlation time for segmental motion is calculated to be 1 multiplied by 10** minus **9 s, in good agreement with published proton NMR data. The results suggest association of pyrrolidone rings in benzene that reduces chain dimensions and also restricts chain mobility. As for PVP-iodine in water, again broad resonances are observed which sharpen considerably at higher temperatures. The result agrees with previous suggestions of specific interactions between the pyrrolidone group and iodine.