|Title||Photo-Reversible Supramolecular Hydrogels Assembled by α-Cyclodextrin and Azobenzene Substituted Poly(acrylic acid)s : Effect of Substitution Degree, Concentration, and Tethered Chain Length|
|Author(s)||Wang, Mingwei; Zhang, Xiaojun; Li, Li; Wang, Junyou; Wang, Jie; Ma, Jun; Yuan, Zhenyu; Lincoln, Stephen F.; Guo, Xuhong|
|Source||Macromolecular Materials and Engineering 301 (2016)2. - ISSN 1438-7492 - p. 191 - 198.|
WUR Plant Breeding
|Publication type||Refereed Article in a scientific journal|
|Keyword(s)||Azobenzene - Photo-responsive - Polymeric hydrogel - Rheology - α-Cyclodextrin|
Photo-reversible supramolecular hydrogels based on the mixture of α-cyclodextrin (α-CD) and azobenzene (Azo) substituted poly(acrylic acid) s were prepared. Effects of substitution degree of Azo, polymer concentration and tethered chain length on the reversible sol-gel transition of these mixtures trigged by Ultraviolet-Visible (UV-Vis) radiation were investigated through rheology and UV-Vis spectroscopy. Their zero-shear viscosities enhanced upon increasing substitution degree of Azo, polymer concentration, and the tethered chain length between Azo grafts and backbone, while the zero viscosities decreased upon adding free α-CD. The binding constant between α-cyclodextrin and azobenzene, which were determined by UV-Vis spectroscopy, showed a strong dependence on the length of tethered chain.