Direct Synthesis of Thermally Responsive DMA/NIPAM Diblock and DMA/NIPAM/DMA Triblock Copolymers Via Aqueous, Room Temperature RAFT Polymerization
We report aqueous, room temperature RAFT polymerization of N-isopropylacrylamide (NIPAM) and, subsequently, its block copolymerization utilizing a poly(N,N-dimethylacrylamide) macro-CTA. A series of thermally responsive AB diblock and ABA triblock copolymers have been prepared. These polymers contain hydrophilic N,N-dimethylacrylamide (DMA) A blocks of fixed molecular weight and temperature-responsive NIPAM B blocks of varied chain length. Using a combination of 1H NMR spectroscopy, T2 relaxation measurements, dynamic light scattering (DLS), and static light scattering (SLS), we demonstrate that these block copolymers are indeed capable of reversibly forming micelles in response to changes in solution temperature and that the micellar size and transition temperature are dependent on both the NIPAM block length and the polymer architecture (diblock vs triblock).
A. J. Convertine et al., "Direct Synthesis of Thermally Responsive DMA/NIPAM Diblock and DMA/NIPAM/DMA Triblock Copolymers Via Aqueous, Room Temperature RAFT Polymerization," Macromolecules, vol. 39, no. 5, pp. 1724-1730, American Chemical Society (ACS), Mar 2006.
The definitive version is available at https://doi.org/10.1021/ma0523419
Materials Science and Engineering
Keywords and Phrases
N,N-dimethylacrylamide (DMA); N-isopropylacrylamide (NIPAM), Copolymerization; Light scattering; Molecular weight; Nuclear magnetic resonance, Block copolymers
International Standard Serial Number (ISSN)
Article - Journal
© 2006 American Chemical Society (ACS), All rights reserved.