A study of thermal degradation of poly(aryl-ether-ether-ketone) using stepwise pyrolysis/gas chromatography/mass spectrometry

✍ Scribed by C. J. Tsai; L. H. Perng; Y. C. Ling

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 205 KB
• Volume: 11
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(199712)11:18<1987::aid-rcm100>3.0.co;2-q

✦ Synopsis

Thermal degradation of poly(aryl-ether-ether-ketone) (PEEK) was investigated using stepwise pyrolysis/gas chromatography/mass spectrometry (Py/GC/MS) by consecutively heating the sample at fixed temperature intervals to achieve narrow temperature pyrolysis conditions. The individual mass chromatograms of the various pyrolysis products were correlated with the pyrolysis temperature in order to elucidate the pyrolysis mechanism. 4-Phenoxyphenol and 1,4-diphenoxybenzene were detected at 450 °C, indicating that the degradation of PEEK was initiated by selective cleavage at chain ends and chain branches. Phenol was detected as the major pyrolysis product by further pyrolysis to 650 °C, which was attributed to the random main chain cleavage of ether groups. At temperatures above 650 °C, chain cleavage at carbonyl ends became the dominant pyrolysis pathway. The high char yield suggested that random main chain scission was accompanied by carbonization. Carbonization was presumably the dominant pyrolysis mechanism at temperatures above 750 °C. Results obtained with the new method indicate the interesting potentials of the technique for the investigation of polymeric materials.