• polymerization
• PLA
• MCC
• green composites
• extrusion
• grafting from
• SI-ROP

The aim is to fabricate sustainable composites by extrusion, which will be processable through the conventional technologies used for plastics, such as injection molding, and suitable for a wide range of industrial applications. The polymer matrix will be composed of poly(lactic acid) (PLA), a biodegradable polyester. The filler will be the Microcrystalline Cellulose (MCC), opportunely functionalized in order to improve its surface compatibility with the matrix. Specifically, the MCC will be grafted with low polymerization degree Poly(L-lactide) (PLLA) by means of a heterogeneous Surface Initiated Ring-Opening Polymerization (SI-ROP) of L-lactide “grafting from” reaction in the melt. To this aim the synthesis will be optimized by varying the reaction conditions (temperature, reaction time, catalyst concentration, monomer to initiator ratio). The innovation is that no solvent, or inert atmosphere are used, as the short reaction time. The obtained MCC-g-PLLA will be then mixed with PLA to fabricate PLA/MCC-g-PLLA composites. The MCC “grafting from” reaction and the resulting PLA/MCC-g-PLLA materials will be investigated in this study. In this regard, the physical and chemical properties (thermal, mechanical, wettability, vapor permeability, morphological) of the PLA/MCC-g-PLLA composites will be compared to those of PLA with unfunctionalized MCC demonstrating that the surface functionalization especially enhances the hydrophobicity and the compatibility within the materials.