POLY 242 |
| Narrowly dispersed, temperature responsive BAB block copolymers capable of forming flower micelles and physical gels in aqueous solution were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Utilizing a difunctional trithiocarbonate allows a triblock with symmetrical outer blocks to be synthesized in two steps. The outer blocks consist of the temperature responsive polymer, poly(N-isopropylacrylamide) (PNIPAM) while the inner block consists of poly(N,N-dimethylacrylamide) (PDMA). Gel permeation chromatography results indicate the triblock copolymer [poly(NIPAM290-b-DMA234-b-NIPAM290)] is narrowly dispersed (polydispersity index =1.03). Depending on the concentration of polymer in solution, either flower micelles or physical gels form at temperatures above the phase transition temperature of PNIPAM. In the current work, dynamic light scattering and rheometric tests are utilized to investigate the concentration dependent morphological transition from unimers to micelles and gels. In addition, rheometric tests indicate that the physical gels have mechanical properties similar to the commercially available in vitro cell growth platform, collagen. |
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Excellence in Graduate Polymer Science Research
8:25 AM-11:40 AM, Monday, April 7, 2008 Hilton New Orleans Riverside -- Grand Salon 18, Oral
Division of Polymer Chemistry |