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Journal ArticleDOI

Kinetics of swelling of gels

Toyoichi Tanaka, +1 more
- 01 Feb 1979 - 
- Vol. 70, Iss: 3, pp 1214-1218
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TLDR
In this article, a theory of the kinetics of the swelling of polyacrylamide gels is presented, which is based on the assumption that the swelling time is determined by the diffusion coefficient of the fluid molecules.
Abstract
We present a theory of the kinetics of the swelling of a gel. The characteristic time of swelling is proportional to the square of a linear dimension of the gel and is also proportional to the diffusion coefficient of the gel network, which is defined as D=E/f where E is the longitudinal bulk modulus of the network, and f is the coefficient of friction between the network and the gel fluid. This constitutes an essential difference between the present theory and the previous theory which is based on the assumption that the swelling time is determined by the diffusion coefficient of the fluid molecules. Experimental data are shown for spheres of 5% polyacrylamide gels and are analyzed using the present theory. The value of the diffusion coefficient obtained from the macroscopic swelling experiments shows excellent agreement with that obtained microscopically using laser light scattering spectroscopy.

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Citations
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Swelling mechanism of porous P(VP‐co‐MAA)/PNIPAM semi‐IPN hydrogels with various pore sizes prepared by a freeze treatment

TL;DR: In this paper, a series of porous gels with various pore sizes were prepared by freeze-treating a conventional hydrogel that contained various amounts of water at − 20 °C.
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An implanted pH sensor read using radiography

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Finite deformation of fast-response thermo-sensitive hydrogels – A computational study

TL;DR: In this paper, the deformation kinetics of a hydrogel are significantly influenced by its geometry; however, the equilibrium swelling ratio of the hydrogels is found to be independent of their geometries.
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Experimental study of swelling and shrinking kinetics of spherical poly(N,N-diethylacrylamide) gel with continuous phase transition

TL;DR: In this article, the authors investigated the kinetics of swelling and shrinking of spherical particles of poly(N,N-diethylacrylamide) (DEAA) gel, prepared with static mixing technology, and separated the shrinking process into late shrinking and initial shrinking by the skin layer effect.
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Cononsolvency of thermoresponsive polymers: where we are now and where we are going.

TL;DR: A review of the recent developments from the experimental, simulation and theoretical fronts, and an outlook on the problems and challenges which are yet to be addressed can be found in this article .
References
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Journal ArticleDOI

Statistical-Mechanical Theory of Irreversible Processes : I. General Theory and Simple Applications to Magnetic and Conduction Problems

TL;DR: In this paper, a general type of fluctuation-dissipation theorem is discussed to show that the physical quantities such as complex susceptibility of magnetic or electric polarization and complex conductivity for electric conduction are rigorously expressed in terms of timefluctuation of dynamical variables associated with such irreversible processes.
Journal ArticleDOI

Spectrum of light scattered from a viscoelastic gel

TL;DR: In this paper, the spectrum of light scattered from thermally excited displacement fluctuations in polyacrylamide gels was measured using optical mixing spectroscopy, and the correlation function for the displacements having wave vector q is predicted for these gels to have the form of an exponential decay: exp(− Γt).