Characterization of radical defects from abrasion and u.v.-photolysis in poly(ethylene terephthalate) fibres
| Autor: | M.D. Pace, C. M. Roland |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Ethylene
Polymers and Plastics Abrasion (mechanical) Chemistry Radical Organic Chemistry Photodissociation Liquid nitrogen Photochemistry medicine.disease_cause law.invention chemistry.chemical_compound law Polymer chemistry Materials Chemistry medicine Electron paramagnetic resonance Spectroscopy Ultraviolet |
| Zdroj: | Polymer. 32:1027-1030 |
| ISSN: | 0032-3861 |
| DOI: | 10.1016/0032-3861(91)90588-a |
| Popis: | Radical products in poly(ethylene terephthalate) fibres are characterized using electron paramagnetic resonance (e.p.r.) spectroscopy. Different radical species are detected depending upon whether mechanical abrasion or ultraviolet (u.v.) light is used to degrade the fibre samples. From u.v.-photolysis at 77 K (liquid nitrogen) e.p.r. signals consistent with carbon-centred radicals are observed having a line shape centred at g = 2.0034. (The g factor is a scalar which depends upon the environment of the unpaired spin. For a free electron g = 2.0023.) From mechanical abrasion at 77 K a completely different e.p.r. pattern of two peaks is recorded consistent with an oxygen-centred species. The spectrum has one component centred at g = 2.0318 and another component centred at g = 2.0094. At room temperature only one signal is detected after decay of overlapping components for both abrasion and u.v. signals. |
| Databáze: | OpenAIRE |
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