POLY 482 |
| Abstract: Double hydrophilic hybrid copolymers of PDMA/PNIPAm were synthesized by a combination of RAFT and ATRP “living” radical polymerizations from a multi functionalized hyperbranched polyglycerol (HPG) core. The incorporation of ATRP and azo initiator was achieved by the derivatization of hydroxyl groups (–OH) of the hyperbranched polyglycerol core. Azo initiator and S,S'-bis(a,a'-dimethyl-a''-acetic acid)trithiocarbonate CTA were utilized for RAFT polymerization of N,N-dimethylacrylamide. The polymerization of NIPAm from polyglycerol core was achieved by ATRP polymerization with HMTETA/Cu(I)Cl and Me6TREN/Cu(I)Cl catalysts at room temperature. Hybrid polymers with various molecular weights and narrow polydispersity were synthesized by adjusting the reaction conditions. The Me6TREN/Cu(I)Cl/(Cu(II)Cl2) catalyst system produced high molecular weights of PNIPAm than the HMTETA/Cu(I)Cl/Cu(II)Cl2 catalyst. At certain compositions of PDMA and PNIPAM, these hybrid polymers produced stable water soluble nanoaggregates above the LCST of PNIPAm (35 oC). With increase in the amount of PNIPAm, the hybrid polymers precipitated from aqueous solution above LCST. These hybrid polymers with reversible hydrophobic regions could be potential candidates for the delivery of hydrophobic drugs at physiological temperature |
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Nanoparticles and Microparticles: Synthesis and Applications
6:00 PM-8:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster
Sci-Mix
Division of Polymer Chemistry |