Photodegradation of polystyrene sensitised by polyhalogenated compounds |
| |
| Affiliation: | 1. Multiuser Health Center Facility (CMulti-Saúde), Federal University of Sergipe, São Cristóvão, SE, Brazil;2. Health Sciences Graduate Program (PPGCS), Federal University of Sergipe, São Cristóvão, SE, Brazil;3. Laboratory of Neurosciences and Pharmacological Assays (LANEF), Department of Physiology, Federal University of Sergipe, Marechal Rondon Avenue, S/N, Rosa Elza, São Cristóvão, Brazil;4. Department of Pharmacy, Federal University of Sergipe, São Cristóvão, SE, Brazil;5. Federal University of Vale do São Francisco, Petrolina, PE, Brazil;6. Department of Botany, Bharathiar University, Coimbatore, India |
| |
| Abstract: | The photosensitised degradation of polystyrene by polyhalogenated compounds has been studied. During the sensitised photo-oxidative degradation in film and in benzene and methylene chloride solutions, there is a rapid decrease of molecular weight observed by viscosity and GPC measurements. A remarkable after-effect, with a decrease in polymer molecular weight, was also detected. The reaction rates and quantum yields for main-chain scissions are greatly increased by dibromotetrachloroethane, tetrabromophenylpropane, tetrabromononane and carbon tetrabromide.The most probable mechanism of photosensitised degradation involves initial formation of bromine atoms which preferentially attack the polymer by hydrogen atom abstraction and bromination. The effect of oxygen on the degradation is also discussed. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
