Lei Lei, Zhang Qi, Shi Shuxian, Zhu Shiping
Department of Chemical Engineering, McMaster University , Hamilton, Canada L8S 4L7.
Langmuir. 2015 Feb 24;31(7):2196-201. doi: 10.1021/la504829j. Epub 2015 Feb 10.
We report herein the design and preparation of microgels that are responsive to both O2 and CO2 gases. The microgels were synthesized through soap-free emulsion copolymerization of O2-responsive monomer 2,3,4,5,6-pentafluorostyrene (FS) and CO2-responsive monomer 2-(diethylamino)ethyl methacrylate (DEA) with N,N'-methylenebis(acrylamide) (BisAM) as the cross-linker. The P(DEA-co-FS) microgels dispersed in aqueous solution could undergo volume phase transitions triggered by O2 and/or CO2 aeration. The particles were very responsive to CO2, while their responsivity to O2 was moderate. Microgels having different levels of the responsivity could be designed and prepared by varying the FS content in the copolymer. The phase transitions were also highly reversible, and the initial states of microgels could be easily recovered by "washing off" the trigger gases with N2. Multicycle O2, CO2, and N2 aerations were applied, and no loss in the dual gas responsivity and switchability was observed.
我们在此报告对氧气和二氧化碳气体均有响应的微凝胶的设计与制备。这些微凝胶是通过以N,N'-亚甲基双丙烯酰胺（BisAM）为交联剂，使对氧气响应的单体2,3,4,5,6-五氟苯乙烯（FS）和对二氧化碳响应的单体甲基丙烯酸2-(二乙氨基)乙酯（DEA）进行无皂乳液共聚而合成的。分散在水溶液中的P(DEA-co-FS)微凝胶可因通入氧气和/或二氧化碳而发生体积相变。这些颗粒对二氧化碳非常敏感，而对氧气的响应程度适中。通过改变共聚物中FS的含量，可以设计和制备出具有不同响应程度的微凝胶。相变也是高度可逆的，通过用氮气“洗去”触发气体，微凝胶的初始状态可以很容易地恢复。进行了多循环的氧气、二氧化碳和氮气通气实验，未观察到双气体响应性和可切换性的损失。
