Sorbonne Université, CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire (IPCM), Polymer Chemistry Team, 4 Place Jussieu, Paris Cedex 05, 75252, France.
Macromol Rapid Commun. 2021 Dec;42(23):e2100556. doi: 10.1002/marc.202100556. Epub 2021 Oct 17.
In this present work, the synthesis of a new family of upper critical solution temperature (UCST)-thermoresponsive polymers based on N-cyanomethylacrylamide (CMAm) is reported. It is demonstrated that the thermally initiated reversible addition fragmentation chain transfer (RAFT) polymerization of CMAm conducted in N,N-dimethylformamide (DMF) is well controlled. The homopolymer presents a sharp and reversible UCST-type phase transition in pure water with a very small hysteresis between cooling and heating cycles. It is demonstrated that the cloud point (T ) of poly(N-cyanomethylacrylamide) (PCMAm) is strongly molar mass dependent and shifts toward lower temperatures in saline water. Moreover, the transition temperature can be tuned over a large temperature range by copolymerization of CMAm with acrylamide or acrylic acid. The latter copolymers are both thermoresponsive and pH responsive. Interestingly, by this strategy sharp and reversible UCST-type transitions close to physiological temperature can be reached, which makes the copolymers extremely interesting candidates for biomedical applications.
在本工作中，报道了一类基于 N-氰甲基丙烯酰胺（CMAm）的上临界溶解温度（UCST）-温敏聚合物的新型家族的合成。结果表明，在 N,N-二甲基甲酰胺（DMF）中进行的 CMAm 的热引发可逆加成-断裂链转移（RAFT）聚合得到了很好的控制。均聚物在纯水中呈现出尖锐且可回复的 UCST 型相转变，在冷却和加热循环之间几乎没有滞后。结果表明，聚 N-氰甲基丙烯酰胺（PCMAm）的浊点（T）强烈依赖于摩尔质量，并且在盐水中向低温移动。此外，通过与丙烯酰胺或丙烯酸共聚，可以在很大的温度范围内调节转变温度。后两种共聚物均具有温敏性和 pH 响应性。有趣的是，通过这种策略可以达到接近生理温度的尖锐且可回复的 UCST 型转变，这使得共聚物成为生物医学应用的极具吸引力的候选物。
