Thermally reversible shape transformation of nano-patterned PNIPAAm hydrogel


In the field of stimuli-responsive polymer research, poly-N-isopropylacrylamide (PNIPAAm) has been widely studied, because this material has unique properties which respond to temperatures near to that of the human body, approximately 36 °C. In this study, a nano-patterned PNIPAAm hydrogel was prepared using UV-irradiation and soft lithography. Chemical changes in the C–C double bonds of the PNIPAAm hydrogel were confirmed by FT-IR analysis. The thermal properties of the hydrogel were analyzed by differential scanning calorimetry (DSC), which confirmed its low critical solution temperature (LCST). The highest gel content of approximately 46% was achieved at 120 min UV-irradiation. The nano-patterned morphology of the PNIPAAm hydrogel exhibited temperature-dependent reversible shape transformation. This study shows that the reversible shape transformation of the PNIPAAm hydrogel was due to swelling and shrinking.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5


  1. 1.

    Lanzalaco S, Armelin E (2017) Poly(N-isopropylacrylamide) and Copolymers: a review on recent progresses in biomedical applications. Gels 3(4):36

    Article  Google Scholar 

  2. 2.

    Gao Y, Wei M, Li X, Xu W, Ahiabu A, Perdiz J, Liu Z, Serpe MJ (2017) Stimuli-responsive polymers: fundamental considerations and applications. Macromol Res 25(6):513–527

    CAS  Article  Google Scholar 

  3. 3.

    Mather PT, Luo X, Rousseau IA (2009) Shape memory polymer research. Annu Rev Mater Res 39(1):445–471

    CAS  Article  Google Scholar 

  4. 4.

    Li W, Liu Y, Leng J (2014) Shape memory polymer nanocomposite with multi-stimuli response and two-way reversible shape memory behavior. RSC Advances 4(106):61847–61854

    CAS  Article  Google Scholar 

  5. 5.

    Liu C, Qin H, Mather PT (2007) Review of progress in shape-memory polymers. J Mater Chem 17(16):1543–1558

    CAS  Article  Google Scholar 

  6. 6.

    Huang WM, Ding Z, Wang CC, Wei J, Zhao Y, Purnawali H (2010) Shape memory materials. Mater Today 13(7):54–61

    CAS  Article  Google Scholar 

  7. 7.

    Alaneme KK, Okotete EA (2016) Reconciling viability and cost-effective shape memory alloy options—a review of copper and iron based shape memory metallic systems. Int J Eng Sci Technol 19(3):1582–1592

    Google Scholar 

  8. 8.

    Pucci A, Bizzarri R, Ruggeri G (2011) Polymer composites with smart optical properties. Soft Matter 7(8):3689–3700

    CAS  Article  Google Scholar 

  9. 9.

    Jochum FD, Theato P (2013) Temperature- and light-responsive smart polymer materials. Chem Soc Rev 42(17):7468–7483

    CAS  Article  Google Scholar 

  10. 10.

    Fleige E, Quadir MA, Haag R (2012) Stimuli-responsive polymeric nanocarriers for the controlled transport of active compounds: concepts and applications. Adv Drug Deliv Rev 64(9):866–884

    CAS  Article  Google Scholar 

  11. 11.

    Zhou Y, Huang WM (2015) Shape memory effect in polymeric materials: mechanisms and optimization. Procedia IUTAM 12:83–92

    Article  Google Scholar 

  12. 12.

    Shang J, Le X, Zhang J, Chen T, Theato P (2019) Trends in polymeric shape memory hydrogels and hydrogel actuators. Polym Chem 10(9):1036–1055

    CAS  Article  Google Scholar 

  13. 13.

    Koetting MC, Peters JT, Steichen SD, Peppas NA (2015) Stimulus-responsive hydrogels: theory, modern advances, and applications. Mater Sci Eng R Rep 93:1–49

    Article  Google Scholar 

  14. 14.

    Cabane E, Zhang X, Langowska K, Palivan CG, Meier W (2012) Stimuli-responsive polymers and their applications in nanomedicine. Biointerphases 7(1):9

    CAS  Article  Google Scholar 

  15. 15.

    Nagase K, Okano T (2016) Thermoresponsive-polymer-based materials for temperature-modulated bioanalysis and bioseparations. J Mater Chem B 4(39):6381–6397

    CAS  Article  Google Scholar 

  16. 16.

    Gandhi A, Paul A, Sen SO, Sen KK (2015) Studies on thermoresponsive polymers: phase behaviour, drug delivery and biomedical applications. Asian J Pharm Sci 10(2):99–107

    Article  Google Scholar 

  17. 17.

    Dong S, Heyda J, Yuan J, Schalley CA (2016) Lower critical solution temperature (LCST) phase behaviour of an ionic liquid and its control by supramolecular host–guest interactions. Chem Comm 52(51):7970–7973

    CAS  Article  Google Scholar 

  18. 18.

    Zhang X-Z, Wu D-Q, Chu C-C (2004) Synthesis, characterization and controlled drug release of thermosensitive IPN–PNIPAAm hydrogels. Biomaterials 25(17):3793–3805

    CAS  Article  Google Scholar 

  19. 19.

    Liu H, Wang S (2014) Poly(N-isopropylacrylamide)-based thermo-responsive surfaces with controllable cell adhesion. Sci China Chem 57(4):552–557

    CAS  Article  Google Scholar 

  20. 20.

    Klouda L, Mikos AG (2008) Thermoresponsive hydrogels in biomedical applications. Eur J Pharm Biopharm 68(1):34–45

    CAS  Article  Google Scholar 

  21. 21.

    Andronescu E, Brown JM, Oktar FN, Agathopoulos S, Chou J, Obata A (2016) Nanomaterials for medical applications: benefits and risks. J Nanomater 2016:2

    Article  Google Scholar 

  22. 22.

    Hamner KL, Alexander CM, Coopersmith K, Reishofer D, Provenza C, Maye MM (2013) Using temperature-sensitive smart polymers to regulate DNA-mediated nanoassembly and encoded nanocarrier drug release. ACS Nano 7(8):7011–7020

    CAS  Article  Google Scholar 

  23. 23.

    Roy I, Gupta MN (2003) Smart polymeric materials: emerging biochemical applications. Chem Biol 10(12):1161–1171

    CAS  Article  Google Scholar 

  24. 24.

    Gupta B, Krishnanand K, Deopura BL (2012) Oxygen plasma-induced graft polymerization of acrylic acid on polycaprolactone monofilament. Eur Polymer J 48(11):1940–1948

    CAS  Article  Google Scholar 

  25. 25.

    Gupta B, Plummer C, Bisson I, Frey P, Hilborn J (2002) Plasma-induced graft polymerization of acrylic acid onto poly(ethylene terephthalate) films: characterization and human smooth muscle cell growth on grafted films. Biomaterials 23(3):863–871

    CAS  Article  Google Scholar 

  26. 26.

    Sun J, Yao L, Gao Z, Peng S, Wang C, Qiu Y (2010) Surface modification of PET films by atmospheric pressure plasma-induced acrylic acid inverse emulsion graft polymerization. Surf Coat Technol 204(24):4101–4106

    CAS  Article  Google Scholar 

  27. 27.

    Zhao D, Qian X, Gu X, Jajja SA, Yang R (2016) Measurement techniques for thermal conductivity and interfacial thermal conductance of bulk and thin film materials. J Electron Packag 138(4):040802

    Article  Google Scholar 

  28. 28.

    Gilcreest VP, Carroll WM, Rochev YA, Blute I, Dawson KA, Gorelov AV (2004) Thermoresponsive poly(N-isopropylacrylamide) copolymers: contact angles and surface energies of polymer films. Langmuir 20(23):10138–10145

    CAS  Article  Google Scholar 

  29. 29.

    Jang J-H, Koh CY, Bertoldi K, Boyce MC, Thomas EL (2009) Combining pattern instability and shape-memory hysteresis for phononic switching. Nano Lett 9(5):2113–2119

    CAS  Article  Google Scholar 

Download references


This work was supported by the research fund from Chosun University (2015-K207133001-1).

Author information



Corresponding author

Correspondence to Jung-Soo Lee.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Kim, B., Lee, J. Thermally reversible shape transformation of nano-patterned PNIPAAm hydrogel. Polym. Bull. (2020).

Download citation


  • Thermo-responsive polymer
  • Nano-pattern
  • Reversible pattern transformation