Journal ArticleDOI
Kinetics of swelling of gels
Reads0
Chats0
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
More filters
Journal ArticleDOI
Concentration of Proteinaceous Solutions with Superabsorbent Hydrogels
TL;DR: In this article, a process for concentrating dilute aqueous bovine serum albumin solutions with superabsorbent cross-linked hydrogels was investigated, where the gel swells by absorbing water only while macromolecules are excluded, thus producing a concentrated retentate.
Journal ArticleDOI
Swelling of thermo-responsive hydrogels.
TL;DR: Numerical analysis demonstrates good agreement between predictions of the model and observations in tests with stress- and strain-controlled programs.
Journal ArticleDOI
Size adjustment of spherical temperature-sensitive hydrogel beads by liquid–liquid dispersion using a Kenics static mixer
TL;DR: In this paper, the Sauter Mean Diameter of spherical hydrogel beads swollen in deionized water at 293 K was measured and correlated with the Weber number, degree of swelling and viscosity ratio.
Journal ArticleDOI
Swelling mechanism in smart polymers responsive to mechano-chemical stimuli
TL;DR: In this article, the responsiveness of smart polymers to a chemical and mechanical stimuli at the same time is considered, being the chemical action typically carried by a solvent medium, the interplay of the fluid absorption mechanism and the chemical triggering one is accounted for.
Journal ArticleDOI
Relationship between drawability of poly(vinyl alcohol) films prepared from semi-dilute solutions and phase separation of the solutions studied in terms of stereo-regularity and degree of polymerization
TL;DR: In this article, the phase separation of polyvinyl alcohol (PVA) in dimethyl sulfoxide/water mixtures was investigated by using light scattering techniques in terms of the degree of polymerization and stereo-regularity.
References
More filters
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