Thermodynamics of Sorption in an Amorphous Perfluorinated Copolymer AF1600 Studied by Inverse Gas Chromatography / Belov N. A.,Safronov A. P.,Yampolskii Yu. P. // MACROMOLECULES. - 2011. - V. 44, l. 4. - P. 902-912.

ISSN/EISSN:

0024-9297 / 1520-5835

Type:

Article

Abstract:

Detailed investigation of infinite dilution sorption of organic vapors (C-7-C-16 n-alkanes, toluene, octafluorotoluene, p-fluorotoluene, 2,3,4,5,6-pentafluorotoluene, perfluorooctane) in perfluorinated copolymer AF1600 (random copolymer of 35 mol \% perfluoroethylene and 65 mol \% 2,2-bis-(trifluoromethyl)-4,5-difluoro-1,3-dioxole) was performed by inverse gas chromatography (IGC). C-13-C-16 n-alkanes were studied in the temperature range including both glassy and rubbery states of the polymer, while sorption of other solutes was investigated only in the glassy state of the perfluorinated copolymer. Retention diagrams of C-13-C-16 n-alkanes showed breakpoints at similar to 150 degrees C which corresponds to T-g of A F1600. Thermodynamic analysis of IGC data in rubbery and glassy states was performed based on the model developed earlier which included evaluation of Flory-Huggins interaction parameter chi and glassy state structual parameters: excess free volume phi(0)(v) polymer cohesion energy epsilon(22), and entropy depression term s(12). It was shown that aliphatic and aromatic hydrocarbons were poor solvents for glassy A F1600. Positive chi values substantially increased when the length of the alkane increases. Fluorinated hydrocarbons were, however, good solvents for AF1600, and their quality improved with the increase in fluorination degree. On the basis of the cohesion energy of AF1600 (-17.76 kJ/mol) evaluated by CAChe 7.5 molecular modeling package, excess free volume of AF1600 in the glassy state was found to be close to 0.12 and slightly dependent on temperature. The entropy effect of sorption in glassy polymer was highly negative with entropy depression proportional to molar volume of solute.

Author keywords:

GLASSY-POLYMERS; SOLUBILITY COEFFICIENTS; VAPOR SORPTION; TEFLON AF1600; PERMEATION; TEMPERATURE; PARAMETERS; PRESSURE; POLYETHYLENE; TRANSITIONS

DOI:

10.1021/ma1025658

Web of Science ID:

ISI:000287391100031

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	FEB 22
Publisher	AMER CHEMICAL SOC
Address	1155 16TH ST, NW, WASHINGTON, DC 20036 USA
Language	English
EISSN	1520-5835
Keywords-Plus	GLASSY-POLYMERS; SOLUBILITY COEFFICIENTS; VAPOR SORPTION; TEFLON AF1600; PERMEATION; TEMPERATURE; PARAMETERS; PRESSURE; POLYETHYLENE; TRANSITIONS
Research-Areas	Polymer Science
Web-of-Science-Categories	Polymer Science
Author-Email	Belov@ips.ac.ru
ResearcherID-Numbers	Yampolskii, Yurii/L-1398-2017
Number-of-Cited-References	45
Usage-Count-Last-180-days	1
Usage-Count-Since-2013	10
Journal-ISO	Macromolecules
Doc-Delivery-Number	721XM