Bismuth-Triflate-Catalyzed Polymerizations of ε -Caprolactone
| Autor: | Mohammed Lahcini, Hans R. Kricheldorf, Takao Yashiro, Steffen M. Weidner, Hicham Qayouh |
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| Rok vydání: | 2011 |
| Předmět: |
inorganic chemicals
Polymers and Plastics Bulk polymerization Chemistry Organic Chemistry Cationic polymerization chemistry.chemical_element Solution polymerization Condensed Matter Physics Ring-opening polymerization Bismuth chemistry.chemical_compound Sulfonate Polymerization Polymer chemistry Materials Chemistry Coordination polymerization Physical and Theoretical Chemistry |
| Zdroj: | Macromolecular Chemistry and Physics. 212:583-591 |
| ISSN: | 1022-1352 |
| DOI: | 10.1002/macp.201000517 |
| Popis: | eCL was polymerized using the triflates of lanthanum, samarium, magnesium, aluminum, scandium, and bismuth as catalysts. Bismuth triflate proved to be extraordinarily reactive, and catalyzed polymerizations of eCL even at 20 °C. Adding DTBMP reduced the polymerization rate only slightly. Furthermore, no evidence of a cationic mechanism was found by end-group analyses. Polymerization at 20 °C either in bulk or in solution only yielded polyesters of low or medium molecular weights (M n up to 30 000 Da). Yet addition of alcohols allowed for a proper control of molecular weight and end-groups. Additionally, low catalyst concentrations and low temperature resulted in narrow molecular weight distributions and polylactones almost free of cyclic compounds. |
| Databáze: | OpenAIRE |
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