Natural lignocellulose has been a significant renewable raw material attributable to its high specific mechanical performance, compared to the benefits of traditional reinforcing fibers. However, the unsatisfactory mechanical performance of lignocellulose-based materials has limited applications in many advanced engineering domains. Herein, we demonstrate that layered bulk delignified nanolignocellulose/brushite composites with a multifold increase in strength and toughness. Our procedure contains the partially removable lignin and hemicellulose from the nanolignocellulose and the precipitating process of brushite on the nanolignocellulose surface via the mechanochemical process and flow-directed assembly followed by hot-pressing, resulting in the complete toppling of cell walls and the densification of the nanolignocellulose/brushite composites with highly ordered layered structures. This composite exhibits an ultrastrong specific strength 1.8-4.4 times higher than that of modified lignocellulose-based materials, which surpasses that of most natural structural materials and some metals and alloys, opening a path for production of ultrastrong lignocellulose-based load-bearing materials in practical applications by various farming and forestry surplus operations.
Keywords: brushite; flow-directed assembly; lignocellulose; mechanical performance; structural material.