Abstract. We develop a general theory of the swelling kinetics of polymer gels, with the view that a polymer gel is a two-phase fluid. The model we propose is a free boundary problem and can be used to understand both contraction and swelling, including complete dissolving or dehydration of polymeric gels. We show that the equations of motion satisfy a minimum energy dissipation rate principle ...

Introduction Previous studies, e.g., by NMR,1,2 fluorescence pho­ tobleaching,3 and dynamic light scattering (DLS),4,5 have shown that the diffusion of noninteracting probe particles in polymer solutions and gels primarily de­ pends on the polymer concentration and the size of the probe. In interpreting these results, it is widely assumed that polymer gels behave like semidilute polymer solu­ t...

Fluoride and acetate-responsive polymer gels were prepared by incorporation of p-nitrophenylthiourea into poly(octadecyl acrylate) gels, and the colours and volumes were changed selectively in the presence of these ions by complexation in THF.

There is a need for stable gel materials for phantoms used to validate optical computerized tomography (CT) scanners used in conjunction with radiation-induced polymerizing gel dosimeters. Phantoms based on addition of light-absorbing dyes to gelatine to simulate gel dosimeters have been employed. However, to more accurately simulate polymerizing gels one requires phantoms that employ light-sca...

Mucosa-adhesive gels can be used as a useful mean of delivering drugs to or via mucosal membranes, and in particular buccal mucosa. Carbomers are among the best mucosa-adhesive materials known. The aim of this study was to compare the results obtained from the mucosa-adhesive strength of aqueous gels containing Carbomers, either alone or in combination, to the data obtained from assessing the d...

Raman spectroscopy are used to characterize the chemical changes in normoxic polyhydroxyethylacrylate gel dosimeter (PHEA) induced by radiation. Irradiations in the low dose region are performed and the polymerizations of PHEA gels are monitored by the observing the changes of Raman shift intensity of the carbon covalent bond of PHEA originated from both monomer and the cross-linker. The variat...

Hyaluronic acid (HA) is a naturally occurring biodegradable polymer with a variety of applications in medicine including tissue engineering, dermatological fillers, and viscosupplementation for osteoarthritis treatment. The cytotoxicity of crosslinking techniques for scaffold fabrication and the high viscosity of viscosupplements have been issues impeding the development of products from HA. Th...

The synthesis these past few years of novel organic molecules that spontaneously 9 self-assemble into a large variety of molecular architecture, particularly generating organogels, has 10 opened up new horizons for preparing functional materials. Here, we present an original 11 preparation path of such materials through the making of hybrid gels of these molecules together 12 with covalent poly...