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Humidity responsiveness of a poly(N-isopropylacrylamide) gel with a PEG/water mixed solvent

Abstract

This manuscript presents the humidity responsiveness of a poly(N-isopropylacrylamide) (PNIPAAm) gel, which was capable of exhibiting volume changes. The strategy for inducing volume changes in the gel capitalized on the differences in PNIPAAm solubility, which stemmed from variations in the polyethylene glycol (PEG) proportions of PEG/water solvent mixtures. Due to the hygroscopic nature of PEG, PNIPAAm gels using PEG as the solvent (weight fraction of PEG, φPEG = 1.00) absorbed ambient moisture, resulting in a decrease in φPEG over time. In concert with this moisture absorption process, the PNIPAAm gel contracted owing to phase separation at a consistent room temperature, which was attributed to the diminished solubility of PNIPAAm in the solvent. During this investigation, we scrutinized the temperature dependency of the optical transmittance and conducted differential scanning calorimetry (DSC) assessments on free PNIPAAm in water across various φPEG values to substantiate phase separation of the system. We then demonstrated that a PNIPAAm gel with a PEG/water mixed solvent underwent volume changes in response to humidity changes. Additionally, humidity-induced shape deformations were realized with a PNIPAAm and poly(N,N-dimethylacrylamide) (PDMAAm) composite gel. This study introduces, for the first time, a humidity-responsive PNIPAAm gel with a PEG/water mixed solvent.

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References

  1. Kim YS, Liu M, Ishida Y, Ebina Y, Osada M, Sasaki T, et al. Thermoresponsive actuation enabled by permittivity switching in an electrostatically anisotropic hydrogel. Nat Mater. 2015;14:1002–7.

    Article  CAS  PubMed  Google Scholar 

  2. Zhu QL, Du C, Dai Y, Daab M, Matejdes M, Breu J, et al. Light-steered locomotion of muscle-like hydrogel by self-coordinated shape change and friction modulation. Nat Commun. 2020;11:5166.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Gerlach G, Guenther M, Sorber J, Suchaneck, Arndt GKF, Richter A. Chemical and pH sensors based on the swelling behavior of hydrogels. Sens. Actuators B. 2005;111-2:555–61.

    Article  Google Scholar 

  4. Zrínyi M, Barsi L, Büki A. Deformation of ferrogels induced by nonuniform magnetic fields. J Chem Phys. 1996;104:8750–6.

    Article  Google Scholar 

  5. Morales D, Podolsky I, Mailen RW, Shay T, Dickey MD, Velev OD. Ionoprinted multi-responsive hydrogel actuators. Micromachines. 2016;7:98.

    Article  PubMed  PubMed Central  Google Scholar 

  6. Richter A, Paschew G, Klatt S, Lienig J, Arndt K-F, Adler H-JP. Review on Hydrogel-based pH sensors and microsensors. Sensors. 2008;8:561–81.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Matsumoto K, Sakikawa N, Miyata T. Thermo-responsive gels that absorb moisture and ooze water. Nat Commun. 2018;9:2315.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Ishidao T, Akagi M, Sugimoto H, Iwai Y, Arai Y. Swelling behaviors of poly(N-isopropylacrylamide) gel in poly(ethylene glycol)-water mixtures. Macromolecules. 1993;26:7361–2.

    Article  CAS  Google Scholar 

  9. Kim SM, Bae YC. Co-nonsolvency effect of thermosensitive N-isopropylacrylamide nanometer-sized gel particles in water–PEG systems. Polymer. 2013;54:2138–45.

    Article  CAS  Google Scholar 

  10. Lv C, Sun X-C, Xia H, Yu Y-H, Wang G, Cao XW, et al. Humidity-responsive actuation of programmable hydrogel microstructures based on 3D printing. Sens Actuators B Chem. 2018;259:736–44.

    Article  CAS  Google Scholar 

  11. Lv C, Xia H, Shi Q, Wang G, Wang Y-S, Chen Q-D, et al. Sensitively humidity-driven actuator based on photopolymerizable PEG-DA films. Adv Mater Interfaces. 2017;4:1601002.

    Article  Google Scholar 

  12. Shibayama M, Morimoto M, Nomura S. Phase separation induced mechanical transition of poly(N-isopropylacrylamide)/water isochore gels. Macromolecules. 1994;27:5060–6.

    Article  CAS  Google Scholar 

  13. Maeda Y, Higuchi T, Ikeda I. Change in hydration state during the coil-globule transition of aqueous solutions of poly(N-isopropylacrylamide) as evidenced by FTIR spectroscopy. Langmuir. 2000;16:7503–9.

    Article  CAS  Google Scholar 

  14. Wu C, Wang X. Globule-to-coil transition of a single homopolymer chain in solution. Phys Rev Lett. 1998;80:4092–4.

    Article  CAS  Google Scholar 

  15. Shibayama M, Mizutani S-Y, Nomura S. Thermal properties of copolymer gels containing N-isopropylacrylamide. Macromolecules. 1996;29:2019–24.

    Article  CAS  Google Scholar 

  16. Osaka N, Shibayama M. Pressure effects on cononsolvency behavior of poly(N-isopropylacrylamide) in water/DMSO mixed solvents. Macromolecules. 2012;45:2171–4.

    Article  CAS  Google Scholar 

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Acknowledgements

This work was financially supported in part by a SENTAN grant (JPMJSN16B3) from the Japan Science and Technology Agency (JST) (awarded to AMA) and MEXT KAKENHI for Transformative Research Area (A) (23721401) to AMA.

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Correspondence to Aya M. Akimoto or Ryo Yoshida.

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Makita, R., Akimoto, A.M., Enomoto, T. et al. Humidity responsiveness of a poly(N-isopropylacrylamide) gel with a PEG/water mixed solvent. Polym J 56, 639–642 (2024). https://doi.org/10.1038/s41428-024-00900-1

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