Blend interaction parameter

Polymer Blend Interaction Parameter, Xu Interaction Parameter, (xlO J/m ) References... 

Stability, and the B parameter must be negative to have miscibility in high molecnlar weight blends. Interaction parameters used in the ensuing sections are not limited to the Flory-Huggins framework and can be viewed as free of equation of state effects. 

FIGURE 3.10 Blend interaction parameter as a function of temperature [2]. 

One method of calculating the different cases of phase diagrams listed here is by expressing the polymer blend interaction parameter, 5 as a fnnction of temperature... 

For AB/C blends of copolymer and homopolymer the effective blend interaction parameter based on the assumptions given by Equations (6.69) and (6.70) ... 

Using the Cantow and Schulz assumption [21], the effective blend interaction parameter [22] can be written as follows ... 

Figure 3.36 shows snapshot of catalyst layer blends obtained after CGMD equilibration in cases where (a) Pt was not included or (b) Pt was included in the simulation blend. Interaction parameters of C particles were selected to mimic properties of VULCAN-type C/Pt particles. They are hydrophobic, with a repulsive interaction with water and Nation sidechains, and semiattractive interactions with other carbon particles and Nation backbones. 

PVC PMMA Penetrant diffusion coefficient determined and appeared to correlate with yi(23) solvent-polymer blend interaction parameter 382... 

In polymer solutions and blends, it becomes of interest to understand how the surface tension depends on the molecular weight (or number of repeat units, IV) of the macromolecule and on the polymer-solvent interactions through the interaction parameter, x- In terms of a Hory lattice model, x is given by the polymer and solvent interactions through... 

In polymer solutions or blends, one of the most important thennodynamic parameters that can be calculated from the (neutron) scattering data is the enthalpic interaction parameter x between the components. Based on the Flory-Huggins theory [4T, 42], the scattering intensity from a polymer in a solution can be expressed as... 

There are many examples known where a random copolymer Al, comprised of monomers 1 and 2, is miscible with a homopolymer B, comprised of monomer 3, even though neither homopolymer 1 or 2 is miscible with homopolymer 3, as illustrated by Table 2. The binary interaction model offers a relatively simple explanation for the increased likelihood of random copolymers forming miscible blends with other polymers. The overall interaction parameter for such blends can be shown (eg, by simplifying eq. 8) to have the form of equation 9 (133—134). 

Another study looked at the miscibihty of E-plastomer-polyisobutylene blends. Blends were prepared from linear E-plastomers and a polyisobutylenes in the entire composition range. Flory-Huggins interaction parameters were determined from DMTA and DSC measurements. The usual technique had to be modified in the case of DSC data, since the Tg of E-plastomers cannot be detected by this technique. The two methods yielded identical results and indicated good interaction of the components, which was supported also by a SEM study and the mechanical properties of the blends. 

Lohse et al. have summarized the results of recent work in this area [21]. The focus of the work is obtaining the interaction parameter x of the Hory-Huggins-Stavermann equation for the free energy of mixing per unit volume for a polymer blend. For two polymers to be miscible, the interaction parameter has to be very small, of the order of 0.01. The interaction density coefficient X = ( y/y)R7 , a more relevant term, is directly measured by SANS using random phase approximation study. It may be related to the square of the Hildebrand solubility parameter (d) difference which is an established criterion for polymer-polymer miscibility ... 

The existence, on a qualitative basis, of the above-mentioned region (homogeneous diblocks and heterogeneous blends) adds measurably to the understanding of much of our earlier data on rubbery/ rubbery systems. We have recently extended this explanation to a more quantitative level by calculating (7 ) values of Mcri t for various AB pairs. The AB interaction parameter for each pair, re-... 

In this equation, all molecules are divided into four groups paraffins (P), olefins (O), naphthenics (N), and aromatics (A). The v values represent the volume fractions of each component used, while the fa values are the blending values, which were calculated for each of the molecular lumps shown in Table 2. Pure component octane numbers used are designated as ON/, but one should note that in the development of the model, 57 molecular lumps were made based on GC analysis, and pure component ONs were assigned to each lump, and not necessarily each pure component. The kt values are calculated interaction parameters between paraffins, olefins, and naphthenics, and are also shown in Table 2. Based on this equation, and knowing the composition and pure octane numbers of a fuel mixture, an estimation of the blending ON may then be made. 

Interaction parameters for polymer blends, 20 322 in surfactant adsorption, 24 138 Interaortic balloon pump, 3 746 Intercalated disks, myocardium, 5 79 Intercalate hybrid materials, 13 546-548 Intercalation adducts, 13 536-537 Intercalation compounds, 12 777 Intercritical annealing, 23 298 Interdiffusion, 26 772 Interdigitated electrode capacitance transducer, 14 155 Interesterification, 10 811—813, 831 Interest expense, 9 539 Interface chemistry, in foams, 12 3—19 Interface metallurgy materials, 17 834 Interfaces defined, 24 71... 

Figure 6.16 shows a snapshot of the carbon-Nafion-water-solvent (CNWS) blend. The final micro structure was analyzed in terms of density map profiles, RDFs, pore size distributions, and pore shapes. The interaction parameters of the carbon particles were selected to mimic the properties of VULCAN-type C/Pt particles. 

Figure 7.17. Predicted phase diagiam for the system (CiiInSe2)i-x(ZnSe)2i (a) stable and metastable equilibrium between dialcopyrite (CH) and zinc-blende (ZB) phases using volume-dependent interaction parameters (b) using a hierarchy of less accurate tqiproximations (<)sorio el al. 1993).

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