Isothermal phase diagrams for the semicrystalline poly-L-lactide (PLLA) and the amorphous poly-DL-lactide (PDLLA) in combination with several solvent-nonsolvent combinations (dioxane/water, dioxane/methanol, chloroform/methanol, and NMP/water) have been determined. The locations of the liquid-liquid miscibility gap, the solid-liquid miscibility gap and the vitrification boundary in the isothermal phase diagrams at 25°C were identified. The liquid-liquid miscibility gap for the systems with PLLA was located in the same composition range as the corresponding systems with PDLLA. For the systems containing PLLA solid-liquid demixing was thermodynamically preferred over liquid-liquid demixing. Attempts were made to correlate the experimental findings with predictions on the basis of the Flory-Huggins theory for ternary solutions using interaction parameters derived from independent experiments. Qualitative agreement was found between the theoretical predictions and the experimentally obtained liquid-liquid miscibility gap. No good agreement was found for the solid-liquid miscibility gap.
|Number of pages||16|
|Journal||Journal of polymer science. Part B: Polymer physics|
|Publication status||Published - 1996|
- Ternary phase diagrams
van de Witte, P., Dijkstra, P. J., van den Berg, J. W. A., & Feijen, J. (1996). Phase behavior of polylactides in solvent-nonsolvent mixtures. Journal of polymer science. Part B: Polymer physics, 34(34), 2553-2568. https://doi.org/10.1002/(SICI)1099-0488(19961115)34:15<2553::AID-POLB3>3.0.CO;2-U