Decoupling and Functionalization of Coupled Polyisobutylene via Alkoxybenzene Quenching
| Autor: | Subramanyam Ummadisetty, Robson F. Storey, C. Garrett Campbell |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Isobutylene
Acrylate Quenching (fluorescence) Polymers and Plastics Organic Chemistry 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Coupling reaction 0104 chemical sciences Inorganic Chemistry chemistry.chemical_compound chemistry Nucleophile Polymer chemistry Materials Chemistry Proton NMR Living polymerization 0210 nano-technology Benzene |
| Zdroj: | Macromolecules. 49:7642-7652 |
| ISSN: | 1520-5835 0024-9297 |
| DOI: | 10.1021/acs.macromol.6b01754 |
| Popis: | During living polymerization of isobutylene, marginal conditions can lead to reaction of carbenium ions with exo-olefin and production of coupled polyisobutylene (PIB). When living PIB containing a coupled fraction is subjected to end-quenching with an alkoxybenzene compound in the presence of TiCl4, the coupling reaction is quantitatively reversed to form the two original chain ends, and the regenerated chains are observed to possess the desired alkoxyphenyl functionality. To demonstrate this phenomenon, various PIB samples were prepared to purposefully contain significant coupled fractions, from 10 to 55 mol %, by quenching living PIB with hindered nucleophiles under marginal conditions. The coupled fractions were quantified by 1H NMR and GPC. Coupled PIB samples were reacted with (3-bromopropoxy)benzene, methoxybenzene, or 4-phenoxy-1-butyl acrylate in the presence of TiCl4 and a source of protic catalyst. Various protic sources were found to be effective including externally added water, adventitious ... |
| Databáze: | OpenAIRE |
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