Journal ArticleDOI
Kinetics of swelling of gels
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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.read more
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Review on Hydrogel-based pH Sensors and Microsensors.
Andreas Richter,Georgi Paschew,Stephan Dipl.-Ing. Klatt,Jens Lienig,Karl Friedrich Arndt,H.-J. Adler +5 more
TL;DR: Transducers are described which are able to convert the non-electrical changes of the physical properties of stimuli-responsive hydrogels into an electrical signal and the specific sensor properties, design rules and general conditions for sensor applications are discussed.
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Theoretical Description of Hydrogel Swelling: A Review
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Harnessing Surface Wrinkle Patterns in Soft Matter
TL;DR: In this paper, two distinct approaches for wrinkle formation, including mechanical stretching/releasing of oxide/PDMS bilayers and swelling of hydrogel films confined on a rigid substrate with a depth-wise modulus gradient, are discussed.
Journal ArticleDOI
Mechanical instability of gels at the phase transition
Toyoichi Tanaka,Shao-Tang Sun,Yoshitsugu Hirokawa,Seiji Katayama,John Kucera,Yoshiharu Hirose,Takayuki Amiya +6 more
TL;DR: In this article, the physical basis underlying the formation and evolution of the pattern on the originally smooth surface of a gel during the phase transition is elucidated, which makes it difficult to understand.
Journal ArticleDOI
Kinetics of discontinuous volume-phase transition of gels
TL;DR: In this paper, the first order volume phase transition of submillimeter gels is investigated for various initial and final states of the transition, showing that the overall volume change is described approximately as a collective diffusion process, but not precisely.
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).
Journal ArticleDOI
An Introduction to the Theory of Elasticity
P. G. Appleby,R. J. Atkin,N. Fox +2 more