UV Light and Temperature Responsive Supramolecular ABA Triblock Copolymers via Reversible Cyclodextrin Complexation

详细信息    查看全文

• 作者：Bernhard V. K. J. Schmidt ; Martin Hetzer ; Helmut Ritter ; Christopher Barner-Kowollik
• 刊名：Macromolecules
• 出版年：2013
• 出版时间：February 12, 2013
• 年：2013
• 卷：46
• 期：3
• 页码：1054-1065
• 全文大小：559K
• 年卷期：v.46,no.3(February 12, 2013)
• ISSN：1520-5835

文摘

A novel triblock macromolecular architecture based on cyclodextrin (CD) complexation is presented. A CD-functionalized biocompatible poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) building block (3800 鈮?M_n 鈮?10鈥?00 g mol^鈥?; 1.29 鈮?膼_M 鈮?1.46) and doubly guest-containing poly(N,N-dimethylacrylamide) (PDMAAm) (6400 鈮?M_n 鈮?15鈥?00 g mol^鈥?; 1.06 鈮?膼_M 鈮?1.15) and poly(N,N-diethylacrylamide) (PDEAAm) (5400 鈮?M_n 鈮?12鈥?00 g mol^鈥?; 1.11 鈮?膼_M 鈮?1.33) segments were prepared via reversible addition鈥揻ragmentation chain transfer (RAFT) polymerization and subsequently utilized for the formation of a well-defined supramolecular ABA triblock copolymer. The block formation was evidenced via dynamic light scattering (DLS), nuclear Overhauser effect spectroscopy (NOESY), and turbidity measurements. Furthermore, the connection of the blocks was proven to be temperature responsive and鈥攊n the case of azobenzene guests鈥攔esponsive to the irradiation with UV light. The application of these stimuli leads to the disassembly of the triblock copolymer, which was shown to be reversible. In the case of PDEAAm containing triblock copolymers, the temperature-induced aggregation was investigated as well.