ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
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:
Gas-liquid chromatography (GLC) has been applied to the study of thermodynamic interactions in poly(vinyl chloride) (PVC) plasticized by di-n-octyl phthalate (DnOP). A number of vapor-phase “probes” were used to evaluate the Flory-Huggins thermodynamic parameter for the PVC-DnOP interaction in stationary phase mixtures of the components which covered the entire composition range. Experiments were carried out in the temperature span of 100-130°C. The interaction parameter was strongly negative, indicating high PVC-DnOP compatibility, up to 0.25 volume fraction of plasticizer. It then became less negative and finally positive at 0.55 volume fraction of DnOP, suggesting a lower compatibility limit. The composition dependence of the interaction parameter and its apparent variation with the chemical nature of the vapor-phase probe may reflect a nonrandom solution of the probe in the stationary phase and/or non-random mixing of PVC-DnOP, particularly at DnOP contents in the limited compatibility range. Evaluations of the influence of DnOP on zero-shear melt viscosity and Tg of compounds indicate that both thermodynamic interactions and volume-of-dilution effects must be taken into account in assessing the effectiveness of the plasticizer.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1976.070200414
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