dimethyl- 1,4-phenylene Oxide). I. Thermodynamic Parameters of Solutions in Toluene
نویسنده
چکیده
New experimental data have been collected on thermodynamic properties of solutions of poly(2,6dimethyl-1,4-phenylene oxide) (PPO) in toluene. The Flory-Huggins interaction parameters g have been determined from light scattering measurements. These values are in agreement with values obtained by osmotic measurements a t low concentrations and they allow the calculation of a melting point curve which fits the experimental melting points. No liquid-liquid phase separation can be calculated, as was concluded in a preceding paper. Spinodals could not be detected by light scattering or DSC-measurements. This also indicates that liquid-liquid phase separation does not occur. The phase separation on cooling of a PPO-toluene solution is thus believed to be a crystallization phenomenon.
منابع مشابه
PHASE SEPARATION IN POLYMER SOLUTIONS . 11 . DETERMINATION OF THERMODYNAMIC PARAMETERS OF POLY ( 2 , 6 - DIMETHYL - l , 4 - PHENYLENE OXIDE ) TOLUENE MIXTURES
In liquid systems where it is possible to perform light scattering experiments at the melting points of polymer solutions without nucleation taking place because of undercooling, the thermodynamic parameters necessary to calculate the correction parameter g in the Flory-Huggins equation as modified by Koningsveld can be determined. In the system poly(2,6-dimethyl 1,4-phenylene oxide)-toluene cr...
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