COPOLYMERS OF N,N-DIMETHYLACRYLAMIDE AND 2-(N-ETHYLPERFLUOROOCTANESULFONAMIDO)ETHYL ACRYLATE IN AQUEOUS-MEDIA AND IN BULK - SYNTHESIS AND PROPERTIES

Hydrophobically modified (HM) associating water-soluble poly(N,N-dimet hylacrylamide) (PDMA) polymers were prepared by free-radical copolymer izations of DMA and 2-(N-ethylperfluoro-octanesulfonamido)ethyl acryla te (FOSA). The polymerizations were carried out in deionized water in the presence of ammonium persulfate at 50 degrees C or in bulk in the presence of AIBN at 65 degrees C. The copolymerization kinetics monito red simultaneously by F-19 and H-1 NMR spectroscopy indicates that DMA and FOSA is incorporated at the same relative rates throughout the po lymerization. The viscosities of the polymer solutions were measured o n a Brookfield viscometer and an Ubbelohde capillary viscometer. A lar ge viscosity enhancement was observed in comparison with PDMA homopoly mer solutions. The effects of polymer concentration, shear rate, surfa ctants, salts, and temperatures on the reduced and Brookfield viscosit ies were investigated. Interestingly, the aqueous solution of the copo lymer prepared in bulk exhibits both hydrophobic interaction and polye lectrolyte effects in the presence of anionic perfluorocarbon surfacta nt. The resulting polymers were also characterized by size exclusion c hromatography and by H-1 and F-19 NMR spectroscopy.