Bulk Phase Behavior

The temperature dependent bulk phase behavior was further study by small angle X-ray scattering (SAXS) at the Diamond synchrotron for bulk samples of P(F)S49- - 

4 Voided Double-Gyroid Thin Film Templates 

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Whereas chain models still allow for a relatively unified treatment of various aspects of amphiphilic systems, such as their bulk phase behavior and the properties of monolayers and bilayers, this is no longer true for the even more idealized models at the next level of coarse graining. These usually have to be adapted very specifically to the problem one wishes to study. 

The performance of demulsifiers can be predicted by the relationship between the film pressure of the demulsifier and the normalized area and the solvent properties of the demulsifier [1632]. The surfactant activity of the demulsifier is dependent on the bulk phase behavior of the chemical when dispersed in the crude oil emulsions. This behavior can be monitored by determining the demulsifier pressure-area isotherms for adsorption at the crude oil-water interface. 

The pure bulk-phase behavior was studied on blends consisting of poly(acryhc acidj/hydroxypropyl cellulose [44], poly(2-vinylpyridine)/end-sufonic acid poly(styrene) [45], and poly(acryHc acid)/poly(N,N-dimethyl-acrylamide) [46]. Goh et al. [47,48] and others [49] have studied an interesting example of [60]fullerenated poly(2-hydroxyethyl methacrylate) with poly(l-vinylimidazole) or poly(4-vinylpyridine) or poly(styrene-co-4-... 

A recent examination of the bulk phase behavior of mixtures (0.5 - 70 mol%) of 8a with CCH-4 by thermal microscopy, DSC, and deuterium NMR spectroscopy with a deuterated analog of 8a has provided a detailed picture of the solubilization of this ketone in the liquid crystalline phases of CCH-4 (42), and provides further clues to the origins of the solute length effect discussed above. This study indicates that the solubilization of 8a in the crystal-B phase is rather more complex... 

Let us turn away briefly from the solution properties and bulk phase behavior of surfaetants. Much has been learned about the properties of surfactant molecules at interfaces by the study of molecules with hydrocarbon chains so long that they are virtually insoluble in water. 

Molecular-based theories are useful for developing rational stabilizer design criteria and investigating the correlation with bulk phase behavior for stabilizers in supercritical fluids. Molecular theories of polymer adsorption, such as the lattice self-consistent field (SCF) theory of Scheutjens and Fleer[69], allow chain structure, adsorption energy, solubility, length, and concentration to be varied independently. Simulation, while more computationally intensive, offers the additional advantages of... 

Surfactant molecules can come in a variety of different shapes and sizes, and these properties tend to affect their bulk phase behavior and their ability to form different self-assembled structures. In this chapter, we look into these effects in more detail and discuss the effects of packing constraints on phase formation. 

How is the situation described above modified when the number of blocks increases from two to three Two types of linear triblock copolymers are possible, ABA and ABC. In both cases, there is little effect on the single-chain behavior. However, the many-chain behavior exhibits qualitatively different features. Two effects are most noticeable. ABA triblock copolymers are capable of forming physical networks while ABC triblock copolymers form distinctive mesophases. The two scenarios have no counterpart in the behavior of diblock copolymers or of monomeric shortchain amphiphiles. Since the bulk phase behavior of ABC block copolymers is discussed at length in Chapter 10 we mostly focus on the behavior of ABA triblock copolymers. 

To specify all length scales, we furthermore set the statistical segment lengths to b = bs = (T. This is consistent with a fully flexible chain model, but in the simulation model we find b 1.22a [99] due to the restriction of bond angles by excluded volume. Our choice does not affect the bulk phase behavior, it does, however, influence the properties of spatially inhomogeneous systems, i.e., interfacial tension and profiles or nucleation barriers. We do not attempt to tune those parameters as to reproduce the temperature-dependent conformational statistics of hexadecane. 

While previous sections have focused on the bulk phase behavior and the properties of interfaces between coexisting bulk phases, the polymer material is often confined in a container or a thin polymer film is supported by a substrate. This confinement... 

The impact of the local ordering between nanorods on the bulk phase behavior is further evidenced by simulations in Reference 177 for smaller aspect ratio nanorods. The phase behavior of a three-bead rod with a three-bead tether more closely resembles the phase behavior of BCP, in that these shorter nanorods tend not to form locally ordered structures. Specifically, smectic C ordering is observed only for low-temperatme states close to the order-disorder... 

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