THERMAL-DEGRADATION OF POLYTETRAFLUOROETHYLENE IN FLOWING HELIUM ATMOSPHERE .2. PRODUCT DISTRIBUTION AND REACTION-MECHANISM

被引：10

作者：

JUN, HS ^{[1
]}

KIM, KN ^{[1
]}

PARK, KY ^{[1
]}

WOO, SI ^{[1
]}

机构：

[1] KOREA ADV INST SCI & TECHNOL,DEPT CHEM ENGN,TAEJON 305701,SOUTH KOREA

来源：

KOREAN JOURNAL OF CHEMICAL ENGINEERING | 1995年 / 12卷 / 02期

关键词：

POLYTETRAFLUOROETHYLENE; THERMAL DEGRADATION; PRODUCT DISTRIBUTION; DIFFUSION EFFECT; DEGRADATION MECHANISM;

D O I：

10.1007/BF02705644

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The thermal degradation of polytetrafluoroethylene was studied in the helium flowing atmosphere and the temperature range 510-600 degrees C. The products of the thermal degradation of polytetrafluoroethylene were analyzed by an on-line gas chromatograph and the product distribution was obtained. The products consist of tetrafluoroethylene (TFE), perfluoropropene (PFP) and cyclic-perfluorobutane (c-PFB). Under most conditions the main product was TFE. The c-PFB was regarded as the secondary product formed from TFE because the formation of c-PFB strongly depended upon the degradation rate. However, the production of PFP was not related to the degradation rate, but it was influenced by diffusion limitation of gaseous product in the sample matrix. These phenomena were also verified with Curie-point pyrolyser. The results showed that the production of PFP reached a maximum point under diffusion limitation condition. The degradation mechanism of polytetrafluoroethylene was proposed in terms of unzipping mechanism and other mechanism like radical chain transfer reaction.

引用

页码：183 / 187

页数：5

共 28 条

[1]

Atkinson B., Atkinson V.A., The Thermal Decomposition of Tetrafluoroethylene, Journal of the Chemical Society (Resumed), (1957)

[2]

Atkinson B., Trenwith A.B., The Thermal Decomposition of Tetrafluoroethylene, Journal of the Chemical Society (Resumed), (1953)

[3]

Buravtsev N.N., Grigor'ev A.S., Kolbanovskii, Kinetics of the Cyclodimerization of Tetrafluoroethyleue and the Thermal Decomposition of Octafluorocyclobutane, Kinetikai Kataliz., 26, 1, (1985)

[4]

Butler J.N., The Thermal Decomposition of Octafluorocyclobutane, J. Am. Chem. Soc., 84, 8, (1962)

[5]

Choi S.K., Park J.D., The Pyrolysis of Polytetrafluoroethylene, J. Kor. Chem. Soc., 20, 2, (1976)

[6]

Drennan G.A., Matula R.A., The Pyrolysis of Tetrafluoro-ethylene, J. Phys. Chem., 72, 10, (1968)

[7]

Errede L.A., The Application of Simple Equations for Calculating Bond Dissociation Energies to Thermal Degradation of Fluorocarbons, J. Org. Chem., 27, (1962)

[8]

Florin R.E., Parker M.S., Wall L.A., The Mechanism of the Depolymerization of Polytetrafluoroethylene with Pyrolytic and Radiolytic Initiation, Journal of Research of the National Bureau of Standards Section A: Physics and Chemistry, 70 A, 2, (1966)

[9]

Florin R.E., Wall L.A., Brown D.W., Hymo L.A., Michaelson J.I., Factors Affecting the Thermal Stability of Polytetrafluoroethylene, Journal of Research of the National Bureau of Standards, 53, (1954)

[10]

Goldfarb I.J., McHenry R.J., Penski E.C., Thermal Degradation of Polymers. I. Aspects of Polytetrafluoroethylene Degradation, Journal of Polymer Science, 58, (1962)

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