Thermal phase behavior

Table 2. Thermal Phase Behavior of PlLs, Including the Glass Transition (Tg), Melting Point (Tm), boiling point (Tb), and Temperature where the Sample Undergoes Chemical Change or Decomposition (7d) (All Temperatures in °C) ...

Henderson, W.A., Pylstra, P., De Long, H.C., Trulove, P.C. and Parsons, S., Crystal structure of the ionic liquid EtNH3N03 insights into the thermal phase behavior of protonic ionic liquids, Phys. Chem. Chem. Phys. 14 (46), 16041-16046 (2012). 

A wide variety of physical properties are important in the evaluation of ionic liquids (ILs) for potential use in industrial processes. These include pure component properties such as density, isothermal compressibility, volume expansivity, viscosity, heat capacity, and thermal conductivity. However, a wide variety of mixture properties are also important, the most vital of these being the phase behavior of ionic liquids with other compounds. Knowledge of the phase behavior of ionic liquids with gases, liquids, and solids is necessary to assess the feasibility of their use for reactions, separations, and materials processing. Even from the limited data currently available, it is clear that the cation, the substituents on the cation, and the anion can be chosen to enhance or suppress the solubility of ionic liquids in other compounds and the solubility of other compounds in the ionic liquids. For instance, an increase in allcyl chain length decreases the mutual solubility with water, but some anions ([BFJ , for example) can increase mutual solubility with water (compared to [PFg] , for instance) [1-3]. While many mixture properties and many types of phase behavior are important, we focus here on the solubility of gases in room temperature IFs. 

In this chapter, the phase behavior and the thermal and mechanical properties of thermotropic polybibenzoates as a function of the structure of the spacer are reviewed. 

B. Characterization of Thermal Properties, Crystallinity, and Phase Behavior of Polyanhydrides... 

Since excellent reviews on block copolymer crystallization have been published recently [43,44], we have concentrated in this paper on aspects that have not been previously considered in these references. In particular, previous reviews have focused mostly on AB diblock copolymers with one crystal-lizable block, and particular emphasis has been placed in the phase behavior, crystal structure, morphology and chain orientation within MD structures. In this review, we will concentrate on aspects such as thermal properties and their relationship to the block copolymer morphology. Furthermore, the nucleation, crystallization and morphology of more complex materials like double-crystalline AB diblock copolymers and ABC triblock copolymers with one or two crystallizable blocks will be considered in detail. 

Zhong, Z. and Sun, X. S. (2005). Thermal characterization and phase behavior of cornstarch studied by differential scanning calorimetry. /. Food Eng. 69, 453-459. 

Navard and Haudin studied the thermal behavior of HPC mesophases (87.88) as did Werbowyj and Gray (2), Seurin et al. (Sp and, as noted above, Conio et al. (43). In summary, HjPC in H2O exhibits a unique phase behavior characterized by reversible transitions at constant temperatures above 40 C and at constant compositions when the HPC concentration is above ca. 40%. A definitive paper has been recently published by Fortin and Charlet ( who studied the phase-separation temperatures for aqueous solutions of HPC using carefully fractionated HPC samples. They showed the polymer-solvent interaction differs in tiie cholesteric phase (ordered molecular arrangement) from that in the isotropic phase (random molecular arrangement). 

Thus different phase behaviors of polyrotaxanes induced different thermal transitions. One-phase or two-phase materials can be obtained simply by proper choice of the components. The easy introduction of highly flexible cyclic components such as crown ethers with low T% surely expands the applications of otherwise brittle polymers into the low temperature range and also improves elasticity. The plasticizing effect of the crown ether is different from that of a normal plasticizer, because the cyclic is permanently connected to the backbone and no migration can occur. 

Preliminary investigations of the liquid crystal phase behavior of these gold nanoparticles initially revealed an enantiotropic nematic phase (based on polarized light optical microscopy and thermal analysis) as well as some pattern formation of the gold nanoparticles in TEM experiments [540, 541],... 

Effect of Pressure on Micelles. While temperature studies of the phase transitions of bilayers and micelles have been performed for some time now, the utilization of pressure as a variable is a more recent development. Variation in temperature of a colloidal aggregate such as a bilayer causes simultaneous changes in thermal energy and volume, whereas isothermal variation in pressure (up to 50 kbar) yields spectroscopic changes due only to volume effects. A review of high pressure vibrational spectroscopy of phospholipid bilayers has recently appeared (74). in which the surprisingly rich barotropic phase behavior of these compounds is explored in detail. 

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