CHED 111 |
| The use of bioactive species in the synthesis of colloidal dispersions resulting in the development of a new generation of colloidal shapes has led to unique film properties that exhibit stimuli-responsive properties. These studies explored the synthesis of poly(ethoxyethyl methacrylate-co-n-isopropylacrylamide) (PEEMA-co-PNIPAm) copolymer utilizing three different copolymer composition ratios. All were prepared in the presence of either 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DCPC) or 1,2-dilauryl-sn-glycero-3-phosphocholine (DLPC) phospholipids with sodium dioctyl sulfosuccinate (SDOSS) as a co-surfactant. Using the combination of phospholipid concentration and copolymer composition, solution morphology can be controlled. High concentrations of NIPAm facilitated spherical PEEMA-co-PNIPAm particles in the presence of DLPC and DCPC stabilizing species. However, lower NIPAm concentration levels in combination with DCPC phospholipid enabled the creation of spherical and tubular entities. The copolymer solutions exhibit lower critical solution temperatures (LCST) which change as a function of copolymer composition. Also, copolymer composition directly effects zeta potential as a function of temperature. Spectroscopic analysis of the film-air (FA) and film-substrate (FS) interfaces revealed that during film formation, mobility of surfactants was inhibited by the presence of DCPC phospholipid. This behavior was attributed to the crosslinking of acetylenic groups in DCPC tails. Teachers participated in the research through the NSF Research Experience for Teachers program. Integration of the research experience into their K – 14 science curricula is discussed. |
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General Posters
7:30 PM-9:30 PM, Sunday, April 6, 2008 Morial Convention Center -- Hall A, Poster
Division of Chemical Education |