Key Lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, PR China.
Macromol Rapid Commun. 2012 Nov 23;33(22):1952-7. doi: 10.1002/marc.201200439. Epub 2012 Aug 21.
A photoresponsive microgel is designed by the combination of a noncovalent assembly strategy with a covalent cross-linking method. End-functionalized poly(ethylene glycol) with azobenzene [(PEG-(Azo)(2))] was mixed with acrylate-modified β-CD (β-CD-MAA) to form photoresponsive inclusion complex through host-guest interaction. The above photoresponsive complex was cross-linked by thiol-functionalized PEG (PEG-dithiol) via Michael addition click reaction. The photoreversibility of resulted microgel was studied by TEM, UV-Vis spectroscopy, and (1)H NMR measurements. The characterization results indicated that the reversible size changes of the microgel could be achieved by alternative UV-Vis irradiations with good repeatability.
一种光响应性微凝胶是通过非共价组装策略与共价交联方法的结合设计而成的。端基功能化的聚乙二醇带有偶氮苯[(PEG-(Azo)(2))]与丙烯酰胺修饰的β-环糊精（β-CD-MAA）混合，通过主客体相互作用形成光响应性包合物。上述光响应性配合物通过巯基功能化的聚乙二醇（PEG-二硫醇）通过迈克尔加成点击反应交联。通过 TEM、UV-Vis 光谱和（1）H NMR 测量研究了所得微凝胶的光致恢复性。表征结果表明，通过交替的 UV-Vis 辐射可以实现微凝胶的可逆尺寸变化，且具有良好的重现性。
