Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Hydrogels diffusion

Hydrogels. Controlled swelling of hydrophilic polymers, derived from the glossy/mbbery properties of polymers, is used to control the rate of dmg release from matrices. In the mbbery state, accompHshed by lowering the polymer s glass-transition temperature to an appropriate level, the dispersed dmg diffuses as the polymer swells in the presence of water. [Pg.231]

In swelling-controlled systems, glassy hydrogels ia particular, the release process is a combination of the diffusion of water iato the system and dmg from the system. Empirically, release from these systems may be expressed as (83) ... [Pg.228]

Amsden, B, An Obstruction-Scaling Model for Diffusion in Homogeneous Hydrogels, Macromolecules 32, 874, 1999. [Pg.607]

Holz, M Lucas, O Muller, C, NMR in the Presence of an Electric Current, Simultaneous Measurements of Ionic Mobilities, Transference Numbers, and Self-Diffusion Coefficients Using an NMR Pulsed-Gradient Experiment, Journal of Magnetic Resonance 58, 294, 1984. Hooper, HH Baker, JP Blanch, HW Prausnitz, JM, Swelling Equilibria for Positively Ionized Polyacrylamide Hydrogels, Macromolecules 23, 1096, 1990. [Pg.613]

Kokufuta, E Jinbo, E, A Hydrogel Capable of Facilitating Polymer Diffusion through the Gel Porosity and Its Application in Enzyme Immobilization, Macromolecules 25, 3549, 1992. Kresge, CT Leonowicz, ME Roth, WJ Vartuli, JC Beck, JS, Ordered Mesoporous Molecular Sieves Synthesized by a Liquid-Crystal Template Mechanism, Nature 359, 710, 1992. [Pg.614]

Diffusion in highly swollen matrices such as hydrogels involves a three-component system in which the polymer-solvent matrix constitutes a continuum through which the solute diffuses. The mode and rate of transport through the... [Pg.474]

GM Zentner, JR Cardinal, J Feijen, S-Z Song. Progestin permeation through polymer membranes. IV. Mechanism of steroid permeation and functional group contributions to diffusion through hydrogel films. J Pharm Sci 68 970-975, 1979. [Pg.483]

JH Kou, GL Amidon, PI Lee. pH dependent swelling and solute diffusion characteristics of poly(hydroxyethyl methacrylate-co-methacrylic acid) hydrogels. Pharm Res 5 592-597, 1988. [Pg.483]

A Domb, GW Davidson HI, LM Sanders. Diffusion of peptides through hydrogel membranes. J Controlled Release 14 133-139, 1990. [Pg.483]

Solute diffusion through hydrogels has been described in terms of two basic mechanisms, the partition and pore mechanisms. The partition mechanism... [Pg.535]

Figure 13 Theoretical predictions of Eq. (31) for diffusion in a hydrogel (jlVfMv -1.8 nnT3) for solutes of different hydrodynamic radii. (From Ref. 174.)... [Pg.537]

See other pages where Hydrogels diffusion is mentioned: [Pg.55]    [Pg.248]    [Pg.140]    [Pg.222]    [Pg.3824]    [Pg.55]    [Pg.248]    [Pg.140]    [Pg.222]    [Pg.3824]    [Pg.2826]    [Pg.329]    [Pg.231]    [Pg.149]    [Pg.121]    [Pg.129]    [Pg.162]    [Pg.193]    [Pg.200]    [Pg.215]    [Pg.183]    [Pg.184]    [Pg.139]    [Pg.139]    [Pg.140]    [Pg.150]    [Pg.604]    [Pg.598]    [Pg.603]    [Pg.608]    [Pg.608]    [Pg.525]    [Pg.27]    [Pg.243]    [Pg.524]    [Pg.458]    [Pg.476]    [Pg.476]    [Pg.480]    [Pg.520]    [Pg.521]    [Pg.536]    [Pg.537]    [Pg.538]    [Pg.538]   
See also in sourсe #XX -- [ Pg.210 , Pg.212 ]



SEARCH



Diffusion in hydrogels

© 2024 chempedia.info