ESCA Analysis of Photodegraded Poly(ethylene terephthalate) Film Utilizing Gas Chemical Modification

✍ Scribed by Nakayama, Y.; Takahashi, K.; Sasamoto, T.

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 624 KB
• Volume: 24
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(19960930)24:10<711::aid-sia184>3.0.co;2-a

✦ Synopsis

The degradation of the surface composition of poly(ethy1ene terephthalate) (PET) film by ultraviolet tight was analysed by ESCA combined with gas chemical modification (GCM) techniques. A new approach for distinguishing phenolic hydroxyl and alcoholic hydroxyl groups was presented, which uses the difference in reactivity of trifluoroacetic anhydride to the phenolic group and to the alcoholic group. The carboxyl group was detected with tritluoroethanol. The ESCA-GCM results showed differences of the chemical composition of the light-facing side and the back side of the PET 6lm. According to photodegradation mechanisms of PET reported by other researchers, carboxyl group formation suggested cleavage of the main chain of PET. The number of the phenolic carbon on the light-facing side corresponded to the existence of 16 phenolic groups per 100 monomeric units.