Wavelength Sensitivity of the Photodegradation of Poly(2,6-dimethyl-1,4-phenylene ether)

Abstract

In order to examine the effect of the wavelength on the photodegradation of poly(2,6-dimethyl-1,4-phenylene ether)(PPE), PPE films were exposed to monochromatic radiation in atomospheric condition at 23°C using Okazaki Large Spectrograph(OLS). The most effective wavelength for the photodegradation of PPE was found to be 300nm. The threshold wavelength of the main-chain scission, oxidation of the side group and the gel formation was around 310nm. Irradiating the monochromatic radiation shorter than 320nm on PPE, similar types of photodegradation prsoducts were obtained. It was found that ether bond breakage (the cleavage of the hydroxyl end group of the polymer) induced by the monochromatic irradiation was followed by the oxidation of methyl group(generation of aldehyde and carboxylic acid), formation of the crosslinking and production of the quinone-methide structure.