Interfacial bonding and adhesion mechanisms are important in determining the final properties of the polymer composite. Molecular dynamics (MD) simulations have been used to characterize the interfacial structure and adhesion behavior of crystalline cellulose planes in contact with polylactic acid. The structure of the PLA at the interface exhibits a shape that can accommodate the structure of the cellulose surface. The adhesion between the PLA and the cellulose surface is affected by the polarity of the functional groups and the surface roughness. The improved adhesion is primarily due to hydrogen bonds formed between the cellulose and PLA molecular chains. Cellulose planes with higher molecular protrusions and greater surface roughness produce stronger adhesion to PLA due to enhanced hydrogen bonding. This study provides a basic insight into the interfacial mechanisms of PLA and cellulose surfaces at the molecular level.
Keywords: adsorption; cellulose; interface; molecular dynamics simulation; polylactic acid.