Spectrometric Investigation on the Thermooxidative Degradation of Ethylene Oxide and Tetra-hydrofuran Co-polyether
- VernacularTitle:多种谱学方法研究环氧乙烷/四氢呋喃共聚醚的热氧降解
- Author:
Shanguo LUO
;
Futai CHEN
;
Huimin TAN
;
Yunjun LUO
;
Jianguo ZHANG
- Publication Type:Journal Article
- From:
Chinese Journal of Analytical Chemistry
2001;29(5):516-521
- CountryChina
- Language:Chinese
-
Abstract:
The thermooxidative degradtion of ethylene oxide and tetra-hydrofuran (EO-THF) co-polyether has been studied by electron spin resonance(ESR),Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The initial degradation site was found to be at the α-carbon of the ether bond. Two free radicals which derived from dehydrogenation and oxygen addition were successfully detected by spin-trapping technique which used α-phenyl-N-tert-butyl nitrone (PBN) as spin trap. Both FT-IR and NMR have been used tofollow structural changes of the copolyether during degradation. Nearly 20 product frngnents including formate,carbonate,methyl,alcohol,methylene-dioxy,hydroperoxide and semiformal have been characterized by 1 D and 2 D NMR.The thermooxidtion of co-polyether preferred to occur on the THF units especially at the alternating linkage of EO and THF.Antioxidant (BHT) not only retarded the thermooxidation but also modified the degradation products with less ester and methylene-dioxy groups but more hydroxyl and methyl groups.
