Swelling and Shrinking Properties of Thermo-Responsive Polymeric Ionic Liquid Hydrogels with Embedded Linear pNIPAAM

International Journal of Molecular Sciences

Simon Gallagher²  Larisa Florea¹  Kevin J. Fraser¹ 

[1] Insight Centre for Data Analytics, Dublin City University, Dublin 9, Ireland; E-Mails:;CLARITY, the Centre for Sensor Web Technologies, National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland; E-Mail:

关键词: polymeric ionic liquids;    ionic liquid;    pNIPAAM;    thermo-response;    swelling;    IPNs;   

DOI  :  10.3390/ijms15045337

来源: mdpi

【 摘 要 】

In this study, varying concentrations of linear pNIPAAM have been incorporated for the first time into a thermo-responsive polymeric ionic liquid (PIL) hydrogel, namely tributyl-hexyl phosphonium 3-sulfopropylacrylate (P-SPA), to produce semi-interpenetrating polymer networks. The thermal properties of the resulting hydrogels have been investigated along with their thermo-induced shrinking and reswelling capabilities. The semi-interpenetrating networks (IPN) hydrogels were found to have improved shrinking and reswelling properties compared with their PIL counterpart. At elevated temperatures (50–80 °C), it was found that the semi-IPN with the highest concentration of hydrophobic pNIPAAM exhibited the highest shrinking percentage of ~40% compared to the conventional P-SPA, (27%). This trend was also found to occur for the reswelling measurements, with semi-IPN hydrogels producing the highest reswelling percentage of ~67%, with respect to its contracted state. This was attributed to an increase in water affinity due to the presence of hydrophilic pNIPAAM. Moreover, the presence of linear pNIPAAM in the polymer matrix leads to improved shrinking and reswelling response compared to the equivalent PIL.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland