Zitieren Sie bitte immer diesen URN: urn:nbn:de:kobv:b43-630349
About Polycondensation, Disproportionation, and Cyclization of Acetylated Poly(L-Lactide) Esters
- L-lactide (LA) is polymerized with ethyl L-lactate or trifluoroethanol as initiators (LA/In = 30/1), and the resulting poly(L-lactide) esters are acetylated with acetic anhydride. The acetylated PLA esters are mixed with SnOct2, dibutyltin bis(4-chlorophenoxide), or dibutyltin bis(pentafluorophenoxide) in solution and crystallized at 120 °C. The doped crystals are annealed at 140 °C or at 160 °C for 7, 14, and 28 days, and the chemical modifications that occurred in the solid state are monitored by matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF) mass spectrometry, gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) measurements. All catalysts promoted polycondensation, while no significant formation of cycles is observed. However, in the presence of SnOct2, disproportionation of chains occurred upon annealing at 120 or 140 °C, and crystallites consisting of extended chains with Mn values ≈3500 – 3600 and low dispersities (Ð < 1.5) areL-lactide (LA) is polymerized with ethyl L-lactate or trifluoroethanol as initiators (LA/In = 30/1), and the resulting poly(L-lactide) esters are acetylated with acetic anhydride. The acetylated PLA esters are mixed with SnOct2, dibutyltin bis(4-chlorophenoxide), or dibutyltin bis(pentafluorophenoxide) in solution and crystallized at 120 °C. The doped crystals are annealed at 140 °C or at 160 °C for 7, 14, and 28 days, and the chemical modifications that occurred in the solid state are monitored by matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF) mass spectrometry, gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) measurements. All catalysts promoted polycondensation, while no significant formation of cycles is observed. However, in the presence of SnOct2, disproportionation of chains occurred upon annealing at 120 or 140 °C, and crystallites consisting of extended chains with Mn values ≈3500 – 3600 and low dispersities (Ð < 1.5) are formed.…


| Autor*innen: | Hans R. Kricheldorf, Steffen WeidnerORCiD, A. Meyer |
|---|---|
| Dokumenttyp: | Zeitschriftenartikel |
| Veröffentlichungsform: | Verlagsliteratur |
| Sprache: | Englisch |
| Titel des übergeordneten Werkes (Englisch): | Macromolecular Chemistry and Physics |
| Jahr der Erstveröffentlichung: | 2024 |
| Organisationseinheit der BAM: | 6 Materialchemie |
| 6 Materialchemie / 6.3 Strukturanalytik | |
| Veröffentlichende Institution: | Bundesanstalt für Materialforschung und -prüfung (BAM) |
| Verlag: | Wiley VHC-Verlag |
| Jahrgang/Band: | 225 |
| Ausgabe/Heft: | 19 |
| Aufsatznummer: | 2400175 |
| DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
| Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten | |
| Freie Schlagwörter: | MALDI-TOF MS; Polycondensation; Polylactides; Transesterifcation |
| Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
| Chemie und Prozesstechnik / Chemische Charakterisierung und Spurenanalytik | |
| Material | |
| Material / Degradationsmechanismen | |
| DOI: | 10.1002/macp.202400175 |
| URN: | urn:nbn:de:kobv:b43-630349 |
| ISSN: | 1521-3935 |
| Verfügbarkeit des Dokuments: | Datei für die Öffentlichkeit verfügbar ("Open Access") |
| Lizenz (Deutsch): | Creative Commons - CC BY-NC-ND - Namensnennung - Nicht kommerziell - Keine Bearbeitungen 4.0 International |
| Datum der Freischaltung: | 05.05.2025 |
| Referierte Publikation: | Ja |
| Datum der Eintragung als referierte Publikation: | 05.05.2025 |
| Schriftenreihen ohne Nummerierung: | Wissenschaftliche Artikel der BAM |


