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Studies on degradation of poly(ethylene oxide) by multistep pyrolysis/gas chromatography with a programmable temperature vaporization injector.

Kaczmarek H., Kowalonek J., Janssen H. G., Lieshout H. P. M. van

Polimery

2000

T. 45, nr 6

433-438

The multistep pyrolysis/gas chromatography technique using a programmable temperature vaporization injector was used to study thermal and photochemical properties of polymers. Pure poly(ethylene oxide) (PEOX) and PEOX + 3% CoCl2 specimens, 20-mm films, were UV-irradiated (2.45 mW/cm2) for 2 and 4 h in air at room temperature and pyrolyzed/gas chromatographed at 200oC, 420oC and 500oC (Fig. 1, 2). The products evolved at 200oC included residual solvent, monomer, catalyst, polymerization additives, and processing aids. At 420oC, degradation attained maximum and the compound concentrations were maximum in PEOX UV-irradiated for 2 h. In the 4-irradiated PEOX, the 420oC chromatographic peaks were less intense. At 500oC, the intensity of the peaks rose as the irradiation time was prolonged. CoCl2 (3%) gave rise to new degradation products. At 420oC and 500oC, irradiation had negligible effect on degradation of PEOX + 3% CoCl2. Scheme 1 illustrates the major interactions accompanying thermal and photochemical degradation of PEOX in the presence of CoCl2.