Phase miscible

This device contains one main reaction and processing path to which several channels are attached, feeding the main stream with additional phases, miscible or immiscible, or withdrawing such phases [28]. As a consequence, phases are either mixed or move as continuous streams side-by-side without intermixing. By this means, bi- or even tri-layered phase arrangement are created. If needed, one phase leaves the other by moving into a side channel. 

EXAMPLE 2-9 The crude oil of Figure 2-30 contains 35 mole percent methane. Will all mixtures of this oil and carbon dioxide be single phase (miscible) ... 

One of the ways to understand the impact of drug composition in phase miscibility of solid dispersions is to calculate the changes in the free energy of mh ffijnjj and plot it against the volume fraction of polymetp0iymer)> as shown in Figure 18.2. 

Considerations when choosing solvents for mobile phases Miscibility... 

The circumstances under which intermetallics form were elucidated by the British metallurgist William Hume-Rothery (1899-1968) for compounds between the noble metals and the elements to their right in the periodic table (Hume-Rothery, 1934 Reynolds and Hume-Rothery, 1937). These are now applied to all intermetaUic compounds, in general. The converse to an intermetaUic, a solid solution, is only stable for certain valence-electron count per atom ratios, and with minimal differences in the atomic radii, electronegativities, and crystal structures (bonding preferences) of the pure components. For example, it is a mle-of-thumb that elements with atomic radii differing by more than 15 percent generally have very little solid phase miscibility. 

FIGURE 11-21 Schematic phase diagram showing the single phase (miscible) and phase-separated (immiscible) regions. 

The only single phase, miscible IPNs reported are homopolymer IPNs, in which both networks are composed of the same polymer, and IPNs based on poly (2,6-dime thy Iphenylene oxide) (PPO) and polystyrene (PS) (18). The corresponding blend of the latter system is miscible and does not undergo thermally induced phase separation below its degradation temperature (19). 

A somewhat similar technique was discovered by Bergbreiter etal. [123]. He found that biphasic solvent systems exhibit an increase in phase miscibility at elevated temperature if special soluble polymers are added (cf. also Section 7.6). An elegant option is to fix the catalyst on this soluble polymer. For example, he used poly(N-isopropylacryl amide) derivatives which are able to bound phosphine ligands coordinated to a Pd catalyst. High yields in Heck- and Suzuki-couplings can be obtained and the catalyst can be recycled (cf. also Section 6.6). 

The binary blends of polycarbonate with polybutylene terephthalate (PBT/PC) or polyethylene terephthalate (PET/PC) are now known to be essentially phase separated blend systems exhibiting two glass transition temperatures in each case, one for the polycarbonate-rich phase, and another for the polyester-rich phase. [Murff et ah, 1984 Huang and Wang, 1986 Wahrmund et ah, 1978]. The evaluation of the amorphous phase miscibility... 

In 2001, it has been independently reported [2, 3] that the fluorous solvent can be skipped by designing fluorinated catalysts that themselves have a temperature-dependent phase miscibility - that is, solubility - in ordinary organic solvents. 

PA/MXD PA-g blends with poly(m-xyltne adipamide) X12 < 0 indicated miscibility in amorphous phase miscibility increased with transamidation during agiug. 9... 

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