Thermo- and pH-Responsive Hydrogels Based on N-Isopropylacrylamide and Allylamine Copolymers


The thermo- and pH-responsive hydrogels were synthesized via copolymerization of N-isopropylacrylamide and al-lylamine hydrochloride monomers. The equilibrium swelling of the hydrogels was studied as a function of temperature and pH in aqueous solutions. It was shown that controlled alteration of the hydrogel phase transition temperature can be achieved by changing their composition and pH of the environment. Increase in content of hydrophilic allylamine from 10 to 60 wt% in monomer mixture causes a shift of the phase transition temperature from 35oC to 47oC. Hydrogels with N-isopropylacrylamide/allylamine hydrochloride mass ratio of 3:2 show the highest pH-response. Values of average molecular weight between polymer cross-links, , and Flory parameter, χ, were calculated using temperature dependences of the equilibrium swelling of the synthesized hydrogel.

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Konovalova, V. , Samchenko, Y. , Pobigai, G. , Burban, A. and Ulberg, Z. (2013) Thermo- and pH-Responsive Hydrogels Based on N-Isopropylacrylamide and Allylamine Copolymers. Soft, 2, 19-26. doi: 10.4236/soft.2013.24005.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] S. Malik, O. Boyko, N. Atkar and W. F. Young, “A Comparative Study of MR Imaging Profile of Titanium U. G. Spizzirri, I.Altimari, F. Puoci, O. I. Parisi, F Iemma, “Innovative Antioxidant Thermo-Responsive Hydrogels by Radical Grafting of Catechin on Inulin Chain,” Carbohydrate Polymers, Vol. 84, No. 11, 2011, pp.517-523.
[2] I. Velthoen, J. Beek and P. Dijkstra, “Thermo-Responsive Hydrogels Based on Highly Branched Poly(Ethylene Gly- col)-Poly(L-Lactide) Copolymers,” Reactive and Functional Polymers, Vol. 71, No. 3, 2011, pp. 245-253.
[3] T. Caykara, “Effect of Maleic Acid Content on Network Structure and Swelling Properties of Poly(N-Isopropy- lacrylamide-Co-Maleic Acid) Polyelectrolyte Hydrogels,” Journal of Applied Polymer Science, Vol. 92, No. 2, 2004, pp. 763-769.
[4] H. Inomata, S. Goto, K. Otake and S. Saito, “Effect of Additives on Phase Transition of N-Isopropylacrylamide Gels,” Langmuir, Vol. 8, No. 2, 1992, pp. 687-690.
[5] M. Meewes, J. Ricka, M. Desilva, R. Nyffenegger and T. Binkert, “Coil-Globule Transition of Poly(N-Isopropy- lacrylamide): A Study of Surfactant Effects by Light Scattering,” Macromolecules, Vol. 24, No. 21, 1991, pp. 5811-5816.
[6] B. Tasdelen, N. Kayaman-Apohan and M. Baysal, “Preparation, Characterization, and Drug-Release Properties of Poly(N-Isopropylacrylamide) Microspheres Having Poly(Itaconic Acid) Graft Chains,” Journal of Applied Polymer Science, Vol. 97, No. 3, 2005, pp. 1115-1124.
[7] G. Chen and A. S. Hoffman, “Graft Copolymers That Exhibit Temperature-Induced Phase Transition over a Wide Range of pH,” Nature, Vol. 373, No. 6509, 1995, pp. 49- 52.
[8] I. Hiroshi, G. Shuichi and S. Shozaburo, “Phase Transition of N-Substituted Acrylamide Gels,” Macromolecules, Vol. 23, No. 22, 1990, pp. 4887-4888.
[9] W. Chi and Z. Shuiqin, “Volume Phase Transition of Swollen Gels: Discontinuous or Continuous?” Macro- molecules, Vol. 30, 3, 1997, pp. 574-576.
[10] S. Sasaki and S. J. Okabe, “Effects of Ions on the Solubility Transition and the Phase-Separation of N-Isopropy- lacrylamide in Water,” Physical Chemistry B, Vol. 115, No. 44, 2011, pp. 12905-12910.
[11] Y. Hirose, Y. Hirokawa and T. Tanaka, “Phase Transition of Submicron Gel Beads,” Macromolecules, Vol. 20, No. 6, 1987, pp. 1342-1344.
[12] H. Yu and D. W. Grainger, “Amphiphilic Thermosensitive N-Isopropylacrylamide Terpolymer Hydrogels Prepared by Micellar Polymerization in Aqueous Media,” Macromolecules, Vol. 27, No. 16, 1994, pp. 4554-4560.
[13] Y. Li and T. J. Tanaka, “Study of the Universality Class of the Gel Network System,” Journal of Chemical Physics, Vol. 90, No. 9, 1989, pp. 5161-5166.
[14] S. J. Hirotsu, “Phase Transition of a Polymer Gel in Pure and Mixed Solvent Media,” Journal of the Physical So ciety of Japan, Vol. 56, No. 1, 1987, pp. 233-242.
[15] C. Tuncer, K. Simin and D. Goеkhan, “Thermosensitive Poly(N-Isopropylacrylamide-Co-Acrylamide) Hydrogels: Synthesis, Swelling and Interaction with Ionic Surfactants,” European Polymer Journal, Vol. 42, No. 2, 2006, pp. 348-355.
[16] L. Hua, W. Xiaogui, Li Hua, X. Wang, Z. Wang and K.Y. Lam, “Multiphysics Modeling of Volume Phase Transition of Ionic Hydrogels Responsive to Thermal Stimulus,” Macromolecular Bioscience, Vol. 5, No. 9, 2005, pp. 904-914.
[17] H. Bishta, L. Wanb, G. Maob and D. Oupicky, “pH- Controlled Association of PEG-Containing Terpolymers of N-Isopropylacrylamide and 1-Vinylimidazole,” Poly- mer, Vol. 46, No. 19, 2005, pp. 7945-7952.
[18] H. Dautzenberg, Y. B. Gao and M. Hahn, “Formation, Structure, and Temperature Behavior of Polyelectrolyte Complexes between Ionically Modified Thermosensitive Polymers,” Langmuir, Vol. 16, No. 23, 2000, pp. 9070- 9081.
[19] V. V. Konovalova, Yu. M. Samchenko, G. A. Pobigay, A. F. Burban and Z. R. Ulberg, “Hydrogel Membranes with pH- and Thermo-Responsive Parameters,” Proceedings of the 15th International Symposium ‘Ars Separatoria 2010’, Torun, 4-7 July 2010, pp. 222-225.
[20] Yu. Samchenko, V. Konovalova, G. Pobigay, A. Burban and Z. Ulberg, “Thermo Sensitive Copolymers Hydrogels with Controlled Phase Transition Temperature,” Reports of Ukrainian NAS, Vol. 8, 2011, pp. 123-129.
[21] P. J. Flory, “Principles of Polymer Chemistry,” Cornell University Press, Ithaca, 1953.
[22] L. Brannon-Peppas and N. A. Peppas, “Equilibrium Swelling Behavior of pH-Sensitive Hydrogels,” Chemical Engineering Science, Vol. 46, No. 3, 1991, pp. 715-722.

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