Synthesis and characterizations of bis(phenoxy)‐amine tin(II) complexes for ring‐opening polymerization of lactide
Autor: | Khamphee Phomphrai, Jiraya Kiriratnikom, Jonggol Tantirungrotechai, Siriwan Praban, Sucheewin Chotchatchawankul, Supajittra Yimthachote |
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Rok vydání: | 2019 |
Předmět: |
Lactide
Polymers and Plastics Aryl Organic Chemistry 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Ring-opening polymerization 0104 chemical sciences chemistry.chemical_compound End-group Monomer chemistry Polymerization Benzyl alcohol Polymer chemistry Pyridine Materials Chemistry 0210 nano-technology |
Zdroj: | Journal of Polymer Science Part A: Polymer Chemistry. 57:2104-2112 |
ISSN: | 1099-0518 0887-624X |
Popis: | A series of tin(II) complexes supported by N₂O₂ bis(phenol)‐amine ligands were prepared from the reactions of the corresponding ligands with Sn[N(SiMe₃)₂]₂ in benzene at room temperature. The ligands were designed to have different substituted group at the ortho‐position on the aryl rings (R = ᵗBu, CH₃) and N‐containing side arm (E = CH₂NEt₂ and pyridine) giving a variation of tin(II) complexes (R = ᵗBu, E = CH₂NEt₂, 2a; R = ᵗBu, E = py, 2b; R = CH₃, E = CH₂NEt₂, 2c; R = CH₃, E = py, 2d). All complexes were characterized by NMR spectroscopy and single‐crystal X‐ray analysis. The single‐crystal X‐ray crystallography revealed that all complexes have a monomeric four‐coordinate tin center with a distorted seesaw structure. All complexes are active for solvent‐free polymerization of l‐lactide at 120 °C giving poly(l‐lactide) with narrow to moderate dispersity (Ð = 1.12–1.56). In the presence of benzyl alcohol during the polymerization, the resulting polymer was found to be linear having benzyl alcohol as the end group while, in the absence of benzyl alcohol, the polymer was cyclic. The large ᵗBu group at the ortho‐position was found to decrease polymerization activity while the more basic CH₂NEt₂ group was found to increase the polymerization activity. The polymerization of rac‐lactide under a similar condition gave PLA having a slight heterotactic bias for all catalysts. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2104–2112 |
Databáze: | OpenAIRE |
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