Controlled ring-opening polymerization of α-amino acid N-carboxyanhydrides in the presence of tertiary amines
| Autor: | Charlotte D. Vacogne, Helmut Schlaad |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Polymers and Plastics
Tertiary amine Chemistry Organic Chemistry Radical polymerization Cationic polymerization 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Chain-growth polymerization Anionic addition polymerization Polymerization Polymer chemistry Materials Chemistry Organic chemistry Living polymerization 0210 nano-technology Ionic polymerization |
| Zdroj: | Polymer |
| ISSN: | 0032-3861 |
| DOI: | 10.1016/j.polymer.2017.07.062 |
| Popis: | The mechanism of the primary ammonium/tertiary amine-mediated ring-opening polymerization of γ-benzyl- l -glutamate N-carboxyanhydride (B l G-NCA) was investigated. Kinetic analyses revealed that the normal amine mechanism (NAM) together with a dormant-active chain end equilibrium were responsible for the controlled nature of this polymerization pathway, but that the polymerization also proceeded via the activated monomer mechanism (AMM). Mixtures of primary amines (1 equiv) and tertiary amines (0–1.5 equiv) were therefore tested to confirm the co-existence of the NAM and AMM and determine the limits for a controlled polymerization. For tertiary amine molar fractions smaller than 0.8 equiv, the reaction times were greatly reduced (compared to primary amine-initiated polymerization) without compromising the control of the reaction. Hence, the polymerization of NCA can proceed in a controlled manner even when the AMM contributes to the overall chain growth mechanism. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect