(693h) Poly(N-isopropylacrylamide-co-benzo-12-crown-4-acrylamide) Hydrogels with Dual Molecular-/Ion-Recognition Responsive Properties

Authors: 
Wei, Y. Y., Sichuan University
Liu, Z., Sichuan University
Zhu, L., Sichuan University
Xie, R., Sichuan University
Ju, X. J., Sichuan University
Wang, W., Sichuan University
Chu, L., Sichuan University

A novel poly(N-isopropylacrylamide-co-benzo-12-crown-4-acrylamide) (poly(NIPAM-co-B12C4Am)) hydrogel with dual molecular-/ion-recognition responsive properties is prepared by using 12-crown-4 as both guest unit for molecular-recognition and host unit for ion-recognition.  This smart hydrogel exhibits high responsivity toward γ-cyclodextrin (γ-CD) and Na+.  Due to the stable formation of 1:1 γ-CD/B12C4 host-guest complexes, the volume phase transition temperature (VPTT) of poly(NIPAM-co-B12C4Am) hydrogel shifts to a higher value at the presence of γ-CD; while, the VPTT shifts to a lower value when crown ethers capture Na2+ and form 2:1 “sandwich” complexes of B12C4/Na+. The results provide valuable guidance for designing and applying poly(NIPAM-co-B12C4Am) smart hydrogels in various applications such as chemical valves, sensors and actuators.