Effects of interfacial stereocomplexation in cellulose nanocrystal-filled polylactide nanocomposites

Cellulose nanocrystals (CNC), extracted from cellulose fibers by the mean of acid hydrolysis, were subjected to ring opening polymerization of d-Lactide initiated from the hydroxyl groups available at their surface. The resulting CNC-g-PDLA nanohybrids were incorporated in poly(l-lactide) (PLLA) matrix through melt-blending and the obtained nanocomposites were characterized in terms of their thermo-mechanical properties. Surface-induced polylactide (PLA) stereocomplexation resulting from the co-crystallization of grafted PDLA chains and unbounded PLLA ones from the matrix was evidenced. Acquired results and a thorough comparison with their counterparts grafted with PLLA chains reveal the effects of the stereocomplexed PLA structure surrounding CNC. Important alterations of both crystalline structure and its behavior of the final materials were observed originated from an efficient nucleation effect induced by the addition of these nanohybrids. Significant enhancement of the mechanical performances was also obtained most probably brought by the stereocomplexation that stiffens and stabilize further the percolation network.