Polymerization of DL-Lactide induced by Protonated Montmorillonite clay as a solid catalyst: Mechanism study

Maghnite- H⁺ is Algerian montmorillonite sheet alumino-silicate clay, exchanged with protons (H⁺). This solid non-toxic catalyst was successfully used as cationic catalyst for the polymerization of D,L-Lactid at 100°C. Interactions between Maghnite-H⁺ platelets and the monomer (D,L-Lactide) were studied by solid state ¹H, ²⁷Al and ²⁹Si NMR spectroscopy. The results show that, the mechanism of the reaction involves both Brønsted and Lewis acid sites on Maghnite surface.

Keywords:
D; L-Lactide; poly (D,L-Lactide); PLA; Solid state NMR; Montmorillonite; Solid Catalyst