Langmuir 2006, 22, 989-997
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Two-Stage Collapse of Unimolecular Micelles with Double Thermoresponsive Coronas Jian Xu,† Shizhong Luo,‡ Wenfang Shi,† and Shiyong Liu*,†,‡ The Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui, China; and Department of Polymer Science and Engineering, UniVersity of Science and Technology of China, Hefei, Anhui, China ReceiVed August 20, 2005. In Final Form: October 8, 2005 Phase transition behavior of unimolecular dendritic three-layer nanostructures with dual thermoresponsive coronas is studied. Successive reversible addition-fragmentation transfer (RAFT) polymerizations of N-isopropylacrylamide (NIPAM) and 2-(dimethylamino)ethyl methacrylate (DMA) were conducted using fractionated fourth-generation hyperbranched polyester (Bolton H40) based macroRAFT agent. At lower temperatures (