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
Citations
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Microfluidic synthesis of tunable poly-(N-isopropylacrylamide) microparticles via PEG adjustment.
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Hydrogel membranes made from crosslinked microgel multilayers with tunable density
Daniel Josef Bell,Simon Ludwanowski,Arne Lüken,B. Sarikaya,Andreas Walther,Matthias Wessling,Matthias Wessling +6 more
TL;DR: In this article, the interparticle cross-linking within a microgel filter cake is used to enable the control of the filter cake compression, which can be adjusted and preserved via crosslinking enabling full control over the thickness and density of the selective layer.
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Synthesis and characterization of thermally-sensitive polymer: Poly(aminomethoxypropylacrylamide)
Erdal Uğuzdoğan,O. S. Kabasakal +1 more
TL;DR: In this paper, a temperature sensitive polymer was obtained by the solution polymerization of 2-amino-1-methoxypropylacrylamide (PAMPA) using azobisisobutyronitrile as the initiator.
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Thermoresponsive thin hydrogel-grafted surfaces for biomedical applications
Jun Kobayashi,Teruo Okano +1 more
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Thermosensitive Poly(N-isopropylacrylamide-co-acrylonitrile) Hydrogels with Rapid Response
TL;DR: In this article, the on-off switch behavior of poly(NIPA-co-AN) hydrogels with different fraction of hydrophobic compo- nent (AN) was investigated.
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