Swelling interface number

NA Peppas, NM Franson. The swelling interface number as a criterion for prediction of diffusional solute release mechanisms in swellable polymers. J Polym Sci Polym Phys Ed 21 983-997, 1983. 

GWR Davidson IH, NA Peppas. Solute and penetrant diffusion in swellable polymers. VI. The Deborah and swelling interface numbers as indicators of the order of biomolecule release. J Controlled Release 3 259-271, 1986. 

Another parameter determining the drug release mechanism from glassy hydrogels, the swelling interface number, Sw has been introduced as ... 

Another parameter that indicates the characteristics of diffusion in polymers is the swelling interface number ( w), a dimensionless number that describes the balance between solvent penetration and drug release ... 

A drug release mechanism from compressed cellulose ether matrices using dimensionless analysis has been discussed (17). A non-Fickian mechanism could be dismissed when calculating the Deborah and the Swelling interface numbers from relaxation, penetrant diffusion, swelling and drug diffusivity data (17). 

Swelling front model, 52 Swelling interface number, 64 Swelling mechanisms, 48-9... 

Another parameter for determining the mechanism of drug release from swellable polymer matrices is the swelling interface number, S ... 

Several approaches have been undertaken to construct redox active polymermodified electrodes containing such rhodium complexes as mediators. Beley [70] and Cosnier [71] used the electropolymerization of pyrrole-linked rhodium complexes for their fixation at the electrode surface. An effective system for the formation of 1,4-NADH from NAD+ applied a poly-Rh(terpy-py)2 + (terpy = terpyridine py = pyrrole) modified reticulated vitreous carbon electrode [70]. In the presence of liver alcohol dehydrogenase as production enzyme, cyclohexanone was transformed to cyclohexanol with a turnover number of 113 in 31 h. However, the current efficiency was rather small. The films which are obtained by electropolymerization of the pyrrole-linked rhodium complexes do not swell. Therefore, the reaction between the substrate, for example NAD+, and the reduced redox catalyst mostly takes place at the film/solution interface. To obtain a water-swellable film, which allows the easy penetration of the substrate into the film and thus renders the reaction layer larger, we used a different approach. Water-soluble copolymers of substituted vinylbipyridine rhodium complexes with N-vinylpyrrolidone, like 11 and 12, were synthesized chemically and then fixed to the surface of a graphite electrode by /-irradiation. The polymer films obtained swell very well in aqueous... 

Using MC simulations Delville and co-workers have investigated the clay-water interface [83-87], The number of hydration layers (2-3) increases suddenly during the swelling process [85]. For hydrated montmorillonite with interlayer sodium counterions it was determined that the water content of the pore is a function of the interlamellar distance. Water molecules are layered in successive shells, whose number (1-4) depends on the available interlayer space [87]. The MD study of structure of water in kaolinite [88] has indicated two types of adsorbed water molecules according to different orientations with respect to the structure of clay sheets with HH vector parallel or perpendicular to the surface. 

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