The use of clay nanofillers offers a potential route to improved barrier properties in polylactide films. Magnesium–aluminium layered double hydroxides (LDHs) are interesting in this respect and we therefore explored synthesis of PLA-LDH nanocomposites by ring-opening polymerization. This method is attractive because it should ensure good dispersion of LDH in the polymer. The effect of adding either LDH carbonate (LDH-CO3) or laurate-modified LDH (LDH-C12) was investigated. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy revealed that exfoliated nanocomposites were obtained when using LDH-C12 but that LDH-CO3 gave a partly phase-separated morphology. Thermogravimetric analysis showed that PLA-LDH combinations exhibited higher degradation onset temperatures and differential scanning calorimetry confirmed that LDHs can act as nucleating agents. However, PLA molecular weight was significantly reduced when in-situ polymerization was conducted in the presence of the LDHs and we suggest that chain termination via LDH surface hydroxyl groups and/or metal-catalyzed degradation could be responsible.
|Journal||Polymer Degradation and Stability|
|Publication status||Published - 2010|
- Solar energy
Katiyar, V., Gerds, N., Koch, C. B., Risbo, J., Hansen, H. C. B., & Plackett, D. (2010). Poly I-lactide-layered double hydroxide nanocomposites via in situ polymerization of I-lactide. Polymer Degradation and Stability, 95(12), 2563-2573. https://doi.org/10.1016/j.polymdegradstab.2010.07.031