Swelling of polymer gels

Another amazing property of polymer networks is their ability to change volume manyfold when exposed to an appropriate solvent. When a network polymer is swollen in a solvent it is called a gel. In this section, the swelling of unentangled gels is treated. At the level of the Edwards tube 

Comparison of the non-affine slip-tube model [Eq. (7.65) using Gx and as adjustable parameters] with experiments, see M. Rubinstein and S. Panyukov, Macromolecules 35, 6670 

The volume fraction 0 of polymer in a swollen (or partly swollen) 

Let (j)Q be the polymer volume fraction in the preparation state where crosslinking was performed, with the gel volume Vq. TKe total amount of polymer in a well-developed gel (with no sol fraction) does not change upon swelling or deswelling. The change of the volume is due entirely to the change in the amount of solvent within the gel  

When an unconstrained macroscopic network polymer is swollen in a solvent, it undergoes uniform swelling by the same amount in all directions. In this case, the linear deformation A in each direction is simply the 1/3 power of the ratio of final and initial volumes V/Vq, or the 1/3 power of the initial and final volume fractions 4 o/(p  

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CJ Durning, KN Morman. Nonlinear swelling of polymer gels. J Chem Phys 98 4275-4293, 1993. 

Mijnlibff, P. F., and W. J. M. Jaspers Thermodynamics of swelling of polymer-network gels. Analysis of excluded volume effects in polymer solutions and polymer networks. J. Polymer Sci. A-2 (in press). 

First, we will describe briefly the biology of secretory cells in general and goblet cells in particular. Next, we will outline our earlier studies on the conformation of mudn networks using dynamic laser scattering. Short discussions on the Donnan swelling properties of the mucin network will bring us to the application of the theory of polymer gel phase transition to explain condensation and decondensation in secretion. 

Vasilevskaya VV, Khokhlov AR. Swelling and collapse of polymer gel in polymer solutions and melts. Macromolecules 1992 25 384-390. 

In this chapter numerical simulations by applying the coupled chemo-electro-mechanical multi-field formulation on a deforming mesh have been performed. It has been shown that this formulation is an excellent method for describing the coupled behaviour of polymer gels in a solution. This method is capable to explain the mechanisms of the behaviour of polyelectrolyte gels under chemical and electrical stimulation, the ion distributions as well as the swelling and bending behaviour. 

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