Effect polymer concentration

Polymer concentration effects on its chemical reactivity - At concentration higher than the... 

Considerations of radical compartmentalization and higher polymer concentration effects are not sufficient to describe the processes that build branched polymer molecules in emulsion polymerization, and the effects of limited space must be properly taken into account [266-269]. 

Figure 5.49 shows the polymer concentration effect on the permeability reduction factor, F, predicted from Eq. 5.36. This figure shows that F is a weak function of polymer concentration, and it increases shghtly within a low concentration range. Concentration quickly reaches a plateau. This effect is consistent with the polymer adsorption shown in Figure 5.43. 

FIGURE 5.49 Polymer concentration effect on Fk, predicted from Eq. 5.36. 

Figure 7.25 shows the GTSP partition when polymer is added. We can see that the addition of polymer reduces the GTSP partition in the oil phase, but the polymer concentration effect is not significant. In an ASP/oil system (see Figure 7.26), the GTSP partition coefficient is between an alkali/oil and a polymer/oil system and is lower than in a water/oil system. 

Figure 1. Experimental viscosity ratio vs. volume fraction polymer concentration effects. (Reproduced with permission from reference 19. Copyright 1992 Society of Petroleum Engineers.)...

Farrokhzad, H., H. Mobedi, J. Barzin, and A. Poorkhalil. Evaluation of polymer concentration effect on doxycycline hyclate drug release from in situ forming system based on poly (lactide-co-glycolide). 

Cui, L., Ding, Y., Li, X., Wang, Z., Han, Y. Solvent and polymer concentration effects on the surface morphology evolution of immiscible polystyrene/poly(methyl methacrylate) blends. Thin Solid Films 515(4), 2038-2048 (2006)... 

Polymers Concentration Effects on ThFFF Separation and Characterization... 

However, with incrccising polymer concentration, effective repulsion of segments of different macromolecules should result in a decrease in the molecular coil sizes. This does qualitatively follow from Equations 113 and 114. An increase in polymer concentration for a labelled (eg. deuterated) macroniolecule can be regarded m effective increase in the solvent molecular volume, which lead.s to a decrease in Cm in Equation 114 and, therefore, to a decrezise in a in Equation 113. In the limit W — 0, the labelled macroniolecule finds itself to be among similar ones (in the thermodynamic and morphological sense). In view of Equations 113 and 114, K/ — 0, Cm —> 0 and o 1. 

Under the conditions of hydrodynamic solicitation of concentrated solutions, in order to explain the polymer concentration effect on the chain splitting mechanism, Y. Minoura and co-workers stated from two hypotheses, namely 1) the interaction between the polymer coil and solvent molecules and 2) the interaction of coil-ing-uncoiling type are essential for mechano-degradation [1045 -1049]. If the last one acts, the increase of concentration must favour the chains splitting, after an exponential law. This behaviou was not experimentally proved. K. Arai shown that the mechano-chemical destruction is not caused by the coiling-uncoiling interac-... 

Michael Rubinstein and Eugene Helfand, Statistics of the entanglement of polymers Concentration effects , J. Chem. Phys., 82,1985, pp 2477-2483. 

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