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The evolution of structure and properties of PNIPA/clay nanocomposite hydrogels with the freezing time in polymerization

Published online by Cambridge University Press:  31 March 2014

Yi Chen
Affiliation:
Key Laboratory of Advanced Materials and Technology for Packaging of Hunan University of Technology, Zhuzhou 412008, China; and Institue of Polymer Research, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
Weijian Xu*
Affiliation:
Institute of Polymer Research, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

To prepare hydrogels with ultrarapid response rate and excellent mechanical properties, the poly(N-isopropylacrylamide)/clay nanocomposite hydrogels were synthesized by freezing polymerization technique. The start freezing time, as an important parameter determining the properties of gels, was designed and investigated. The results showed that the properties of gels including mechanical properties, swelling ratio, and swelling/deswelling rate were closely dependent on the freezing polymerization time. Comparably, the gels synthesized with earlier freezing time exhibit a faster swelling rate and an ultrarapid deswelling rate due to the integral interconnecting porous structure, while the swelling ratio, tensile strength and modulus decrease considerably. With the delay of start freezing time, the response rate decreases while the mechanical properties improve. Through the analysis of scanning electron microscope, differential scanning calorimetry, x-ray diffraction, dynamic rheological tests, and mechanical tests, the relevance of gels' structure with the freezing time was explored. It is reasonably presumed that freezing process impacts the effective crosslink of polymer chains by clay significantly, the earlier the freezing started, the more chains with free end existed in gels.

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Articles
Copyright
Copyright © Materials Research Society 2014 

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References

REFERENCES

Hou, Y.P., Matthews, A.R., Smitherman, A.M., Bulick, A.S., Hahn, M.S., Hou, H.J., Han, A., and Grunlan, M.A.: Thermoresponsive nanocomposite hydrogels with cell-releasing behavior. Biomaterials 29, 3175 (2008).CrossRefGoogle ScholarPubMed
De, S.K., Aluru, N.R., Johnson, B., Crone, W.C., Beebe, D.J., and Moore, J.: Equilibrium swelling and kinetics of pH-responsive hydrogels: Models, experiments, and simulations. J. Microelectromech. Syst. 11, 544 (2002).CrossRefGoogle Scholar
Zhao, Y.L. and Stoddart, J.F.: Azobenzene-based light-responsive hydrogel system. Langmuir 25, 8442 (2009).CrossRefGoogle ScholarPubMed
Liu, J.H., Chen, G.S., Guo, M.Y., and Jiang, M.: Dual stimuli-responsive supramolecular hydrogel based on hybrid inclusion complex (HIC). Macromolecules 43, 8086 (2010).CrossRefGoogle Scholar
Suzuki, H. and Kumagai, A.: New type of glucose sensor based on enzymatic conversion of gel volume into liquid column length. Biomacromolecules 5, 486 (2004).CrossRefGoogle ScholarPubMed
Dai, H.J., Chen, Q., Qin, H.L., Guan, Y., Shen, D.Y., Hua, Y.Q., Tang, Y.L., and Xu, J.A.: Temperature-responsive copolymer hydrogel in controlled drug delivery. Macromolecules 39, 6584 (2006).CrossRefGoogle Scholar
Burdick, J.A., Khademhosseini, A., and Langer, R.: Fabrication of gradient hydrogels using a microfluidics/photopolymerization process. Langmuir 20, 5153 (2004).CrossRefGoogle ScholarPubMed
Hirotsu, S. and Onuki, A.: Volume-phase transitions of gels under uniaxial tension. J. Phys. Soc. Jpn. 58, 1508 (1989).CrossRefGoogle Scholar
Takigawa, T., Araki, H., Takahashi, K., and Masuda, T.: Effects of mechanical stress on the volume phase transition of poly(N-isopropylacrylamide) based polymer gels. J. Chem. Phys. 113, 7640 (2000).CrossRefGoogle Scholar
Gehrke, S.H.: Synthesis, equilibrium swelling, kinetics, permeability and applications of environmentally responsive gels. Adv. Polym. Sci. 110, 81 (1993).CrossRefGoogle Scholar
Kato, N. and Gehrke, S.H.. Microporous, fast response cellulose ether hydrogel prepared by freeze-drying. Colloids Surf. B: Biointerfaces 38, 191 (2004).CrossRefGoogle ScholarPubMed
Kaneko, Y., Yoshida, R., Sakai, K., Sakurai, T., and Okano, T.: Temperature-responsive shrinking kinetics of poly (N-isopropylacrylamide) copolymer gels with hydrophilic and hydrophobic comonomers. J. Membr. Sci. 101, 13 (1995).CrossRefGoogle Scholar
Kaneko, T., Asoh, T.A., and Akashi, M.: Ultrarapid molecular release from poly(N-isopropylacrylamide) hydrogels perforated using silica nanoparticle networks. Macromol. Chem. Phys. 206, 566 (2005).CrossRefGoogle Scholar
Zhang, X.Z. and Chu, C.C.: Fabrication and characterization of microgel-impregnated, thermosensitive PNIPAAm hydrogels. Polymer 46, 9664 (2005).CrossRefGoogle Scholar
Dogu, Y. and Okay, O.: Swelling-deswelling kinetics of poly(N-isopropylacrylamide) hydrogels formed in PEG solution. J. Appl. Polym. Sci. 99, 37 (2005).CrossRefGoogle Scholar
Tokuyama, H. and Kanehara, A.: Novel synthesis of macroporous poly(N-isopropylacrylamide) hydrogels using oil-in-water emulsions. Langmuir 23, 11246 (2007).CrossRefGoogle ScholarPubMed
Zhang, Z., Yang, Y.Y., and Chung, T.S.: Effect of mixed solvents on characteristics of poly(N-isopropylacrylamide) gels. Langmuir 18, 2538 (2002).CrossRefGoogle Scholar
Miyata, T., Asami, N., Okawa, K., and Uragami, T.: Rapid response of a poly(acrylamide) hydrogel having a semi-interpenetrating polymer network structure. Poly. Adv. Technol. 17, 794 (2006).CrossRefGoogle Scholar
Mahdavinia, G.R., Marandi, G.B., Pourgavadi, A., and Kiani, G.: Semi-IPN carrageenan-based nanocomposite hydrogels: Synthesis and swelling behavior. J. Appl. Polym. Sci. 118, 2989 (2012).CrossRefGoogle Scholar
Xue, W., Champ, S., Huglin, M.B., and Jones, T.G.J.: Rapid swelling and deswelling in cryogels of crosslinked poly(N-isopropylacrylamide-co-acrylic acid). Eur. Polym. J. 40, 467(2004).CrossRefGoogle Scholar
Strachotová, B., Strachota, A., Uchman, M., Šlouf, M., Brus, J., Pleštil, J., and Matějka, L.: Super porous organic-inorganic poly(N-isopropylacrylamide)-based hydrogel with a very fast temperature response. Polymer 48, 1471 (2007).CrossRefGoogle Scholar
Haraguchi, K., Takehisa, T., and Fan, S.: Effects of clay content on the properties of nanocomposite hydrogels composed of poly(N-isopropylacrylamide) and clay. Macromolecules 35, 10162 (2002).CrossRefGoogle Scholar
Haraguchi, K., Farnworth, R., Ohbayashi, A., and Takehisa, T.: Compositional effects on mechanical properties of nanocomposite hydrogels composed of poly(N,N-dimethylacrylamide). Macromolecules 36, 5732 (2003).CrossRefGoogle Scholar
Haraguchi, K. and Li, J.H.: Control of the coil-to-globule transition and ultrahigh mechanical properties of PNIPA in nanocomposite hydrogels. Angew. Chem. Int. Ed. 44, 6500 (2005).CrossRefGoogle ScholarPubMed
Haraguchi, K. and Song, L.Y.: Microstructures formed in co-cross-linked networks and their relationships to the optical and mechanical properties of PNIPA/Clay nanocomposite gels. Macromolecules 40, 5526 (2007).CrossRefGoogle Scholar
Endo, H., Miyazaki, S., Haraguchi, K., and Shibayama, M.: Structure of nanocomposite hydrogel investigated by means of contrast variation small-angle neutron scattering. Macromolecules 41, 5406 (2008).CrossRefGoogle Scholar
Ozmen, M.M., Dragan, E.S., and Okay, O.: Formation of macroporous poly(acrylamide) hydrogels in DMSO/water mixture: Transition from cryogelation to phase separation copolymerization. React. Funct. Polym. 68, 1467 (2008).CrossRefGoogle Scholar
Xue, W., Hamley, I.W., and Huglin, M.B.: Rapid swelling and deswelling of thermoreversible hydrophobically modified poly(N-isopropylacrylamide) hydrogels prepared by freezing polymerization. Polymer 43, 5181 (2002).CrossRefGoogle Scholar
Lutecki, M., Strachotová, B., Uchman, M., Brus, J., Pleštil, J., Šlouf, M., Strachota, A., and Matějka, L.: Thermosensitive PNIPA-based organic–inorganic hydrogels. Polym. J. 38, 527 (2006).CrossRefGoogle Scholar
Tobolsky, A.V., Carlson, D.W., and Indictor, N.: Rubber elasticity and chain configuration. J. Polym. Sci. 54, 175 (1961).CrossRefGoogle Scholar
Nielsen, L.E.: Mechanical Properties of Polymers and Composites, Vol. 1 (Mercel Dekker Inc., New York, 1974), p. 23.Google Scholar
Ricciardi, R., D’Errico, G., Auriemma, F., Ducouret, G., Tedeschi, A.M., De Rosa, C., Laupretre, F., and Lafuma, F.: Short time dynamics of solvent molecules and supramolecular organization of poly(vinyl alcohol) hydrogels obtained by freeze/thaw techniques. Macromolecules 38, 6629 (2005).CrossRefGoogle Scholar