| Abstract: | Photooxidative degradation of poly-2,5-distyrylpyrazine (poly-DSP) has been studied in detail. Both amorphous poly-DSP film and poly-DSP solution were photooxygenated and degraded by irradiation by sunlight in the air. The nitrile group was formed, together with carbonyl groups and hydroxyl group. The photodegradation of a pyrazine derivative to a nitrile derivative is a new reaction. Next, photodegradation behavior of polymers having a cyclobutane moiety in the main chain, poly-1,4-bis[2-(2-pyridyl)-vinyl]benzene (poly-P2VB) and polydiethyl p-phenylenediacrylate (poly-p-PDA Et), was studied. The photodegradability of these polymers decreases in the order: poly-DSP > poly-P2VB ? poly-p-PDA Et. Further, the photodegradation behavior of various vinyl polymers containing a vinylpyrazine or vinylpyridine component and polyamides having pyrazine or pyridine ring in the main chain, was investigated. Of these, polyvinylpyrazine has the largest photodegradability. |
