Dependence of interaction parameter

Muramoto, A., "Dependence of Interaction Parameter on Molecular Weight and Concentration for Solutions of Poly(dimethylsiloxane) in Methyl Ethyl Ketone," Polymer, 23, 1311 (1982). 

FIGURE 14 The dependence of interaction parameter e on macromolecular coil fractal dimension Dj. A hnear macromolecule characteristic states according to the classification [10] are indicated by points. 

The system PS dissolved in cyclohexane, sketched in Figure 3, displays an UCST. At high temperatures cyclohexane is a good solvent. It turns into a poor solvent for temperatures below 35.4 °C (0 temperature). Expansion factor a was calculated as a function of temperature after Equation (13). Temperature dependence of interaction parameter % might be represented by ... 

Fig. 1. Schematic temperature dependence of interaction parameters resulting from different ts pes of interactions in a pol3aner blend. (1-dispersive interactions, 2-free-volume interactions, 3-specific interactions, A-sum of 1-1-2, B-sum of 1-I-2-I-3).

BCA2 Kaddour, L.O., Anasagasti, M.S., and Strazielle, C., Molecular weight dependence of interaction parameter and demixing concentration in polymer-good solvent systems. Comparison with theory, MaAro/wo/. Chem., 188, 2223,1987. 

MUR Mrrramoto, A., Dependence of interaction parameter on molectrlar weight and concentration for solutiorts of poly(dimethylsiloxane) in methylethylketone, Polymer, 23, 1311, 1962. 

Figure 8.6 Temperature dependence of interaction parameters for mixtures of deuterated and hydrogenous vinyl butadienes. % =Xab = Xcd.X2 = Xad = Xbc,X = Xac = Xbd Reproduced with...

Figure 7.8. Concentration dependence of interaction parameter for PS-PBMA (a) and PMMA-PBMA (b) alloys 1-without filler, 2-with filler (calculation according to the first method), 3-calculation according to the second method. [Adapted by permission from Y. S. Lipatov in Controlled Interphases in Composite Materials, Ed. Ishida, Elsevier, Amsterdam, 1990, p. 594]...

Huang, J.-C. (2004) Concentration dependency of interaction parameter between PVC and plasticizers using inverse gas chromatography. J. Appl. Polym. Sci.,... 

In Figure 17.1, the dependence of interaction parameter e on the concentration of PBT Cpg for the considered blends PET/PBT is adduced. This plot has two features. Firstly, it is a mirror reflection of the dependence of the considered blends impact toughness on their composition, adduced in work, and secondly, all values e are positive, that is, the repulsion interactions are dominant for all considered blends. The indicated mirror reflection of the parameters and e supposes growth at e reduction, that is, repulsion interaction weakness. 

FIGURE 17.1 The dependences of interaction parameter e on PBT content Cpg.j. for blends PET/PBT, prepared by extrusion and subsequent injection molding (1) and injection molding only (2). 

Figure 7.31 Composition dependence of interaction parameter X for a PMMA/PVDF pair at 187 C, which was obtained from small-angle X-ray scattering (O) and melting point depression (A). (Reprinted from Wendorff, Journal of Polymer Science, Polymer Letter Edition 18 439. Copyright 1980, with permission from John Wiley Sons.)...

Table 3 Coefficients of temperature and concentration dependence of interaction parameter...

An evident parallel variation of the increment in re and in the bond length rX is observed. On the other hand, the influence of the strengths of the X—Y bonds on the activation energies in these reactions were taken into account. The electronegativities of C and Si, Ge, Sn atoms are close. The empirical dependence of the parameter re (in m) on DXy and rXY in the interaction of radicals carrying a free valence on the C and O atoms with the C—H, Si—H, Sn—H, Ge—H, and P—H bonds is presented on Figure 6.5. 

Methodology of spatial-energy parameter helps not only to explain experimentally determined dependencies of interactions of these elements with free radicals, but also provides practical solution for searching new reagents with given properties. 

Two-constant equation of state phase behavior calculations for aqueous mixtures often require the use of temperature dependent binary interaction parameters. The methods used for evaluating these parameters for some of the typical aqueous binary pairs found in coal gasification and related process streams are described. Experimental and predicted phase compositions based on these methods are illustrated for aqueous pairs containing CO2. H2S, NH3, and other gases. 

In principle, all the molecular parameters in Eq. (6) can be determined independently, so that the theory can be quantitatively compared with experimental data. An example of Maxwell s construction in the dependence of x °n critical value of interaction parameter %c of charged PAAm network with the degree of ionization equals to the molar fraction of the sodium methacrylate in the chain i = xMNa = 0.012 are given in Fig. 4 (data of series D from Fig. 5). The compositions of the phases

critical value of Xc were determined by the condition that areas St and S2 defined in Fig. 4 are equal The experimental (p2e is higher and 2 determined by Maxwell s construction (Eq. 13). Thus, the experimental values of (p2e and metastable region the limits of which (p2s and (p2s are determined by the spinodal condition (two values

[Pg.182]

Relaxation measurements provide a wealth of information both on the extent of the interaction between the resonating nuclei and the unpaired electrons, and on the time dependence of the parameters associated with the interaction. Whereas the dipolar coupling depends on the electron-nucleus distance, and therefore contains structural information, the contact contribution is related to the unpaired spin density on the various resonating nuclei and therefore to the topology (through chemical bonds) and the overall electronic structure of the molecule. The time-dependent phenomena associated with electron-nucleus interactions are related to the molecular system, and to the lifetimes of different chemical situations, for the resonating nucleus. Obtaining either structural or dynamic information, however, is only possible if an in-depth analysis of a series of experimental results provides sufficient data to characterize the system within the theoretical framework discussed in this chapter. 

Simultaneous evolution of sequences and conformations. In the work [71], the simultaneous evolution of sequences and conformations was studied. This design procedure leads to the final state that depends on the set of interaction parameters and on the rearrangements both in conformational space... 

The activation energy thus found reflects the overall effect of temperature on a few parameters characterising the process of interaction of those phases (see equation (5.19)). Not only is the temperature dependence of each of them characterised by its own activation energy, but it may well happen to be quite different from temperature dependences of other parameters. Therefore, both sets of activation energies prove to be of little practical value, irrespective on whether these were calculated from an ascending or from a descending portion of an experimental kinetic relationship. 

The character of temperature dependence of order parameter r =r (T) is defined to a large extent by the value and sign of the quantity 8. The evaluation showed that >0, oo2<0, oo3=2cn2<0, as is shown later. It should be noted that energetic parameter c i is defined by interaction between d>-Pt pairs and energetic parameter (o2 is determined by interaction between -H pairs. 

Oxidations of the two molecules appear to proceed almost but perhaps not quite wholly independently of each other the dissociative chemisorption of hydrogen is not much affected by the carbon monoxide, which, in view of what was said in Chapter 5, is somewhat surprising, as there it seemed that both interacted with lowly coordinated gold atoms. The dependence of kinetic parameters on the hydrogen concentration has not been... 

We emphasize two natural limitations of the finite cluster model. It does not allow to make a statement about the dependence of essential parameters such as adsorption and transition energies on the level of surface coverage, and it does not account adequately for charge delocalization or surface relaxation phenomena. Further, it excludes by definition any information about the modification of the surface band structure as a consequence of the organic molecule adsorption. The following case study of 1-propanol on Si(001) - (2 x 1) is intended to clarify how these elements can be consistently incorporated into the description of the Si surface interaction with organic species. 

Experimental data on the dependence of exchange parameters (the rate of triplet-triplet energy transfer (kTT) or the spin exchange integral (Jse)) on the distance (r) between interacting centers are approximated by the following equation (Likhtenshtein 1988(a,b), 1993,1995 Likhtenshtein et al. 1982 Kotel nikov et al. 1981)... 

FIGURE 7.1. Dependence of surface coverage on phase-boundary potential (a) and corresponding depression of interfacial tension (b) for absorption modelled by Frumkin isotherm at two values of interaction parameters (o = 1.0 (curve 1) and 2.0 (curve 2). Adapted from Figure 1 in Ref. [15]. 

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