Ring-opening copolymerization of L-lactide and epsilon-caprolactone in supercritical carbon dioxide using triblock oligomers of caprolactone and PEG as stabilizers
Özet
In this study, the use of triblock (A-B-A) oligomers of epsilon-caprolactone (epsilon-CL) (A) and PEG400 (B) as stabilizers (SB) for the copolymerization of L-lactide (LLA) and epsilon-CL in supercritical carbon dioxide (scCO(2)) was investigated. To determine the effect of CO2-philic and polymer-philic segments on copolymerization, oligomers with three different average molecular weights (M-w=2000-6000 Da) were synthesized by changing the PEG400/epsilon-CL ratio. Copolymerizations were confirmed by H-1-nuclear magnetic resonance (NMR), C-13-NMR and differential scanning calorimeter data. It was possible to copolymerize LLA and e-CL in scCO(2) without any SB; however, the polymerization yields and average molecular weights were low, and significant aggregate formations were detected. Recipes featuring only 5% SB were successfully applied to reach high polymerization yields of similar to 85% and polymers with average molecular weights greater than 20 kDa. When the polymer-philic segment of the SB increased, both the yield and molecular weight of the copolymer also increased significantly, resulting in white powdery products. Polymer Journal (2011) 43, 785-791; doi: 10.1038/pj.2011.70; published online 27 July 2011
Anahtar kelimeler
Atıf için künye
Yılmaz, M., Egri, S., Yildiz, N., Calimli, A., & Piskin, E. (2011). Ring-opening copolymerization of L-lactide and epsilon-caprolactone in supercritical carbon dioxide using triblock oligomers of caprolactone and PEG as stabilizers. POLYMER JOURNAL, 43(9), 785–791. https://doi.org/10.1038/pj.2011.70
BibTeX
@article{yilmaz2011-198055,
author = {Yılmaz, Mehmet and Egri, Sinan and Yildiz, Nuray and Calimli, Ayla and Piskin, Erhan},
title = {Ring-opening copolymerization of L-lactide and epsilon-caprolactone in supercritical carbon dioxide using triblock oligomers of caprolactone and PEG as stabilizers},
journal = {POLYMER JOURNAL},
year = {2011},
volume = {43},
number = {9},
pages = {785--791},
issn = {0032-3896},
doi = {10.1038/pj.2011.70},
url = {https://akademik.atauni.edu.tr/yayinlar/198055-ring-opening-copolymerization-of-l-lactide-and-epsilon-caprolactone-in}
}