Bio-inspired clay nanosheets/polymer matrix/mineral nanofibers ternary composite films with optimal balance of strength and toughness

Abstract

Although remarkable progress has been witnessed in mimicking the nacre-like architecture in laboratory, it remains a great challenge for understanding the unique balancing mechanism of toughness and strength in biological materials. Here, taking advantage of the synergistic effect of different dimensional nanoscale building blocks, we fabricate nacre-like films that reconcile high strength and toughness. The obtained ternary lamellar composite films are constructed by one-dimensional xonotlite nanowires and two-dimensional montmorillonite nanosheets with the assistance of poly(vinyl alcohol). The ternary composite films show high strength ( (241.8±10.2) MPa) and toughness ((5.85±0.46) MJ m−3), both of which are higher than that of the single nanofibrillar xonotlite network films or the binary montmorillonite/poly(vinyl alcohol) composite films. The excellent mechanical properties of the nacre-like ternary composite films are aroused by the synergistic toughening mechanism of the different dimensional building blocks. This strategy provides a facile approach to integrate the nacre-like composite films with potential applications in tissue engineering scaffold, strong air barrier coatings, and fire-retardant packing materials.