ISSN:
0032-3888
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
The thermodynamic phase behavior of two polymer-liquid crystal blends was investigated in both the solid and molten states. One of the blends (p-hexyloxybenzoic acid and poly[ethylene glycol]) contains a semi-crystalline polymer. The second example (p-pentyloxycinnamic acid and bisphenol-A polycarbonate) contains a high-impact-resistant amorphous thermoplastic. Whereas, the former system is almost completely immiscible at ambient temperature, yet advantageous for applications in the microelectronics industry, the latter blend exhibits partial (concentration-dependent) miscibility. Our multi-technique assessment of miscibility/phase separation includes high-resolution carbon-13 solid state NMR spectroscopy, differential scanning calorimetry (DSC), and group-contribution thermodynamics (Universal Quasi-Chemical Functional-Group Activity Coefficient formalism including a Free Volume correction for the small molecule activity, UNIFAC-FV). Approximate temperature-composition (equilibrium) phase diagrams are constructed for both blends in light of the results from NMR, DSC, and UNIFAC-FV.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pen.760281407
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