Thermo-sensitive swelling behavior in crosslinked N-isopropyl-acrylamide networks: Cationic, anionic and ampholytic hydrogels
- Oregon Graduate Institute of Science & Technology, Beaverton, OR (United States)
Crosslinked polymer networks of N-isopropylacrylamide (NiPAAm) containing small amounts of either anionic or cationic co-monomers, or mixture of both, were fabricated and characterized in terms of their aqueous media between a highly solvated, swollen gel state and a collapsed, dehydrated network over temperature ranges comparable to that of pure NiPAAm, with modifications of gel critical points and respective temperature ranges dependent upon co-monomer type and content. At temperatures exceeding the collapse transition point, all copolymer gels collapse to a state of nearly complete dehydration, demonstrating short-time collapsed-state swelling ratios far lower than those of pure MiPAAm networks. Collapse kinetics for the ionmeric gels are much more rapid than those of pure NiPAAm, achieving collapse state equilibrium on time scales of seconds. Swelling behavior as a function of pH and temperature is detailed over a range of copolymer compositions.
- OSTI ID:
- 141735
- Report Number(s):
- CONF-930304--
- Country of Publication:
- United States
- Language:
- English
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