Effect of equivalent weight

The effects of equivalent weight (FW = g polymer/mol SO3H) and water content on diffusion coefficient, solubility, and permeability of oxygen for fully hydrated BAM, S-SEBS, ETFE- -PSSA, Nafion 117, and BPSH membranes have been studied. It has been found that the diffusion coefficients of all the studied membranes decrease with increasing EW, while the solubility correspondingly increases. These trends are the same as found in... 

Basura, V. I., Chuy, C., Beattie, P. D. and Holdcroft, S. 2001. Effect of equivalent weight on electrochemical mass transport properties of oxygen in proton exchange membranes based on sulfonated a,j3,j3-trifluorostyrene (BAM) and sulfonated-styrene-(ethylene-butylene)-styrene triblock (DAIS-analytical) copolymers. Journal ofElectroanalytical Chemistry 501 77-88. 

Atkins, J. R., Sides, C. R., Greager, S. E., Harris, J. L., Pennington, W. T., Thomas, B. H. and DesMarteau, D. D. 2003. Effect of equivalent weight on water sorption, PTFE-like crystallinity, and ionic conductivity in bis[(perfluoroalkyl) sulfonyl] imide perfluorinated ionomers. Journal of New Materials for Electrochemical Systems 6 9-15. 

Figure 5. Effect of equivalent weight on the wide angle X-ray scattering curves of the short-side-chain precursor.

Figure 13b. Expansion of the high temperature region showing the effect of equivalent weight on the storage modulus.

The degree of crystallinity in the polymer is only moderately altered, compared to the effect of equivalent weight, when the polymer is hydrolyzed, as demonstrated in Figure 3. Although the crystallinity does decrease somewhat upon hydrolysis, it is clear the hydrolyzed polymer is still partly crystalline. Similar results are obtained for polymer in other cation forms. Thus, any ionic clustering which exists in the polymer does not completely disturb the crystalline portion of the matrix. 

In the next section we will present the data and arguments on which the cluster-network model is based. We will also discuss the effects of equivalent weight, ion form, and water content on the dimensions and composition of the clusters. In the third section we will present a formalism, which follows from the cluster-network model, based on absolute reaction rate theory (2) and hydroxyl rejection in "Nation perfluorinated membranes. Finally we will outline the concepts of percolation theory and demonstrate that ion transport trough "Nation" is well described by percolation. 

Effect of equivalent weight IM methanol, 80°C, 3L oxygen (0 psig)... 

Jalani NH, Datta R (2005) The effect of equivalent weight, temperature, cationic forms, sorbates and nanoinorganic additives on the sorption behaviour of Nafion. J Membr Sci... 

The components (MAMS, MADS, DADS, DAMS Fig. 1) that make up the commercial blend of alkyldiphenyl oxide disulfonates were evaluated individually in both built and unbuilt formulations to determine the effect of equivalent weight on detergency performance (Fig. 10) Measuranents were obtained on dust/sebum and ground-in-clay soils on cotton, cotton/polyester, and polyester fabric. 

Fig. 11.11 Room temperature protrai craiductivity of the short side chain (SSC) PFSA ionraner at 2 different (i.e., Dow 858 and Dow 1084 gionomer per molH+) equivalent weights (EW) and Nafirai as a function of water content expressed as 2 = [H20]/[—SO3H]. The data clearly shows the significant effect the equivalent weight has rat protrai conductivity with the Dow 858 exhibiting conductivity twice that of the higher EW PFS As (Reproduced from K. D. Kieuer et al. [52] by Elsevira Sdraice)...

The conclusion that might be drawn is that response variables are adequately described without information from the lead variables, as the lead variables were not selected to the best subset of regressors in either year 1 or year 2. The fact that the selection order of the best regressors was identical for the three response variables at each year indicates that the explanatory variables have equivalent effects on both mental and psychomotor functioning. The decrease in the effectiveness of birth weight over the first 2 years was coupled with an increasing importance of home environment, effects which have been suggested before in the developmental literature. 

Derivatives of hemicellulose components have properties similar to the ceUulosic equivalents but modified by the effects of thek lower molecular weight, more extensive branching, labile constituents, and more heterogeneous nature. Acetates, ethers, carboxymethylxylan (184), and xylan—poly(sodium acrylate) (185) have been prepared. 

Effect of Fiber Properties. Acid dyes are attracted to the accessible amine ends of the nylon chains located in the amorphous regions of the fiber. Acid dye affinity of nylon can be adjusted by a dding excess diamine or diacid to the polymer salt or by changing the molecular weight in polymerization. A light acid-dyeable nylon-6,6 is spun with 15—20 amine ends, expressed in terms of gram equivalents per 10 g of polymer. A medium or... 

---