Impact-Resistant Nanocomposite Plastics Embedding “Plant Cell Walls”-Mimicked Frameworks with Ultratrace Amounts of Amphiphilic Cellulose Nanofibrils

Cellulose nanofibrils (CNFs) have been employed as sustainable, eco-friendly fillers in high-performance nanocomposites, although such materials may exhibit poor impact tolerance. The present work synthesized high impact-resistance plastics based on plant cell-wall-like frameworks produced by coating 500 μm isotactic polypropylene (iPP) microspheres with ultratrace amounts of amphiphilic bamboo CNFs prepared by the aqueous counter collision method. These microspheres were spontaneously coated when combined with a suspension containing 0.03 wt %/iPP of the CNFs by vibrational mixing under ambient conditions. A simple injection molding process was used to induce the fusion of the coated iPP microspheres and generate a three-dimensional framework of CNFs resembling a plant cell wall structure. This framework with ultralow amounts of amphiphilic CNFs was found to improve the impact shock resistance of the plastic. The facile, eco-friendly process reported herein could be used to facilitate the upcycling of plastics and thus promote the sustainable use of resources.