Responsive gels

Aggeli A, Bell M, Boden N et al (1997) Responsive gels formed by the spontaneous self-assembly of peptides into polymeric beta-sheet tapes. Nature 386 259-262... 

Geckeler, K, E, Soluble Polymer Supports for Liquid-Phase Synthesis. VoL 121, pp. 31-80. Gehrke, S, H. Synthesis, Equilibrium Swelling, Kinetics Permeability and Applications of Environmentally Responsive Gels. Vol. 110, pp. 81 -144. de GenneSy P.-G> Flexible Polymers in Nanopores. VoL 138, pp. 91-106. 

K Dusek, ed. Responsive Gels Volume Transitions I. Adv Polym Sci Ser 109. Heidelberg Springer-Verlag, 1993. 

SH Gehrke, DC Harsh. Environmentally responsive gels. In JC Salamone, ed. Polymeric Materials Encyclopedia, Vol 3. Boca Raton, FL CRC Press, 1996, pp 2093-2102. 

SH Gehrke. Synthesis, equilibrium swelling, kinetics, permeability and applications of environmentally responsive gels. Adv Polym Sci 110 81-144, 1993. 

M Palasis. The influence of interactions on the diffusion of solutes in responsive gels. PhD Dissertation, University of Cincinnati, Cincinnati, OH, 1994. 

With regard to the response time of the gel, polyelectrolyte gels require seconds to minutes to deform in electric fields. Needless to say, the deformation speed depends on the thickness of the gel and the intensity of the applied field. In 1993, a fast-responsive gel was found by Nanavati and Fernandez. A secretory granule gel particle obtained from beige mice and having a diameter of 3 pm at negative potentials was transparent and swollen within milliseconds of the application of an electric field of 5000 V/cm [19]. 

Fig. 13a, b. Biomimetic actuators using electric field-responsive gels a robot hand having four smart gel fingers which can hold a quail egg, and b artificial fish with a tail of gel film which can swim under ac electric fields... 

A.R. Khokhlov, In K. Dusek (Ed.), Responsive Gels Volume Transitions I., Springer Verlag, Berlin, 1992, p. 125. 

Gehrke, S. H. Synthesis, Equilibrium Swelling, Kinetics Permeability and Applications of Environmentally Responsive Gels. Vol. 110, pp. 81-144. 

Another interesting characteristic about many responsive gels is that the mechanism causing the network structural changes can be entirely reversible in nature. This behavior is depicted in Fig. 3 for a pH- or... 

Aggeli, A., Bell, M., Boden, N., Keen, J. N., Knowles, P. F., McLeish, T. C., Pitkeathly, M., and Radford, S. E. (1997). Responsive gels formed by the spontaneous self-assembly of peptides into polymeric beta-sheet tapes. Nature 386, 259-262. 

Gehrke, S. H. in Responsive Gels Volume Transitions II, Springer-Verlag, New York, 1993, 81-144. 

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