Polymers mobility

Intermixing of the polymer mobility control fluid with the surfactant slug can result in surfactant - polymer interactions which have a significant effect on oil recovery (476). Of course, oil - surfactant interactions have a major effect on interfacial behavior and oil displacement efficiency. The effect of petroleum composition on oil solubilization by surfactants has been the subject of extensive study (477). 

Magnetic resonance (ESR, NMR) Chemical structure, tacticity, conformation, polymer mobility (NMR) Radical, triplet state structure and behaviour (ESR)... 

After radiation, a strong upsurge in conductivity then decreased and leveled off after about an hour. This was analyzed in terms of trap filling, which showed a linear dependence on the exposure rate, X, at the radiation induced current Ir. For this polymer, mobility of the holes greatly exceeded that of electrons.(12) Additional studies done by electron pulse... 

Drug substance Monomer and crosslinker used to prepare the polymer Mobile phase References... 

Application of an external electric field causes the charges generated in the bright regions of the pattern to migrate (in polymers mobile charge carriers are holes)... 

INJECTION VOLUME 20 ml (400 mg polymer) MOBILE PHASE THF FLOWRATE 50 ml/min DETECTOR Rl (R403), 64X... 

Radioprotection. The processes of crosslinking and degradation observed in polymers irradiated in the pure state can also be observed in polymers irradiated in solution. The presence of a solvent can intervene in the reaction in several ways thus it allows increased polymer mobility, and some of the radiolytic products of the solvent may react with the polymer or with the polymer radicals, etc. The polymer-water system is of particular interest in that it provides a simple model for some radiobiological systems and can be analyzed far more readily. 

Keywords Polymer mobility Confined polymers Thin films... 

PVA, close to 80°C. The polymer chains become mobile at the glass transition, allowing a partial re-organization of the nanotubes in the matrix and a modification of the conducting network. The polymer mobility allows some relaxation in the structure with possible better intertube contacts and loss of nanotube alignment which favors the contact probability. Both mechanisms can explain improvements of conductivity at the glass transition of the polymer. 

Surface-bound, neutral, hydrophilic polymers such as polyethers and polysaccharides dramatically reduce protein adsorption [26-28], The passivity of these surfaces has been attributed to steric repulsion, bound water, high polymer mobility, and excluded volume effects, all of which render adsorption unfavorable. Consequently, these polymer modified surfaces have proven useful as biomaterials. Specific applications include artificial implants, intraocular and contact lenses, and catheters. Additionally, the inherent nondenaturing properties of these compounds has led to their use as effective tethers for affinity ligands, surface-bound biochemical assays, and biosensors. 

Dahlberg C, Fureby A, Schuleit M, et al. Polymer mobilization and drug release during tablet swelling. A H-1 NMR and NMR microimaging study. J Control Release 2007 122(2) 199-205. 

Fig. 7.2.25 (a) Arbitrary mobility timescale of a semicrystalline polymer. Mobile (m),... 

Case visc02 is the same as Case viscOl, except that the oil viscosity is increased to 100 mPa s, and the polymer concentration is adjusted using Eq. 4.5 so that the polymer mobility is equal to the total mobility of oil and water phases ahead of the displacing front. In this case, Pp = 1.98 mPa s. 

Case viscOS is the same as Case visc02, except that the polymer concentration is adjusted so that the polymer mobility is the same as the oil mobility only (not total mobility). Note that in Case viscOS, as well as in Cases viscOl and visc02, the initial oil saturation is 0.5. In this situation, the cross-section area available for polymer to displace the oil phase is half the whole cross-section area. The other half cross-section area is used for polymer to displace the water phase ahead. In other words, the polymer mobility to displace the oil is reduced by half. Mathematically, we should determine the polymer viscosity required using the following equation ... 

There are numerous references that show a correlation between matrix properties and reaction rates (Labuza et al., 1977 Roos, 1993 Bell and Hageman, 1994 Buera and Karel, 1994 Bell, 1996), but arguably not to the exclusivity of solvent-based effects, and never with a direct link to the mobility of the reactant itself rather than the polymer. Yet there are a handful of studies that come very close to showing a direct link between reactant mobility and polymer mobility. 

Fig. 2. Traces along the proton dimension of 2D-WISE experiments performed on 10% hydrated (left) and 35% hydrated (right) onion cell wall material. The corresponding carbon resonances are given. Proton spectral widths of 150 and 70 kHz were used for the 10 and 35% hydrated samples respectively. Reprinted from Carbohydr. Res., Vol. 322(1-2), S. Hediger, L. Emsley and M. Ficher, Solid-state NMR characterization of hydration effects on polymer mobility in onion cell wall material , pp. 102-112, Copyright 1999, with permission from Elsevier Science.

Nano scale (local level) proton accessibility to site, electrocatalysis, polymer adsorption, polymer mobility... 

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