High‐Strength, High‐Barrier Bio‐Based Polyester Nanocomposite Films by Binary Multiscale Boron Nitride Nanosheets

Abstract

Owing to the inferior dispersibility of boron nitride nanosheets (BNNSs) and weak interfacial interaction with the matrix, the performance of BNNS‐based composites is usually far below theoretically predicted values. Here, binary multiscale BNNSs (LDH‐BNNSs) fillers are synthesized through in situ growth of layered double hydroxide (LDH) on the BNNSs’ surfaces. LDH‐BNNSs with a multiple mosaic interface show superior dispersion of nanosheets in matrix and extraordinary filler‐matrix bonding. Density functional theory simulations reveal the stable dispersion mechanism of LDH‐BNNSs. Moreover, the bio‐based poly(ethylene furandicarboxylate) composites with 0.2 wt% LDH‐BNNSs loading exhibit simultaneous improvements in tensile strength (≈140 MPa), Young's modulus (≈6.5 GPa), toughness (≈2.0 MJ m−3), and gas barrier properties. Regulation of the interfacial structures of binary multiscale BNNSs significantly increases the filler utilization of the nanosheets, leading to extraordinary stress transfer efficiency and a physical shielding effect. Therefore, this simple, efficient, and novel strategy has promised in enhancing composite performance, and it provides a novel way to develop strong, tough, and high‐barrier bio‐based polyester composites.

Bioinspired Strong and Tough Poly(ε-caprolactone)/Graphene Nanodot Composite Films via Weak Hydrogen Bonds: Implications for Thermal–Mechanical Properties

“…Compared to the PCL sample (Figure S4), the GNDs/PCL nanocomposites show the typical H-bond cross-linking network and matrix deformation structure in Figure 6d. Due to the strong nanoconfinement phase around GNDs resulting from multiscale H-bond interactions, 60 the fracture morphology of the GNDs/PCL nanocomposite film exhibits the pull out of PCL chains in Figure 6e. Meanwhile, a 3D H-bond cross-linking network can be clearly observed at the fracture interface in Figure 6f.…”

Boron Nitride-Based Polyester Nanocomposite Films with Enhanced Barrier and Mechanical Performances

“…As confirmed from the in-situ Raman spectra in Figure 6l, because BNNS withstand load transfer and energy dissipation during the stretching, crystal structures of BNNS undergo significant deformation. 31 In short, we have successfully unveiled the mechanism for the strengthening and toughening, which jointly interpret the collaborative improvement in strength, Young's modulus, and toughness of BNNS/ PEF composites.…”

“…29 The incorporation of BNNS can lead to improvements in the mechanical properties of polymers, including tensile strength, modulus, elongation at break, and toughness. 30,31 Furthermore, BNNS can exhibit good compatibility with the polymer matrix, leading to improved interfacial adhesion. 32 This compatibility is crucial for achieving a homogeneous dispersion of BNNS within the polymer matrix and improving the barrier properties of polymer.…”

“…32 This compatibility is crucial for achieving a homogeneous dispersion of BNNS within the polymer matrix and improving the barrier properties of polymer. 31,32 However, the modifiers must also simultaneously meet the growing requirements for green sustainability, superior dispersion, and film formation owing to the inferior film-forming properties of BNNS. In addition, seldom have studies been made to understand the critical role of dispersion capability and internally ordered architectures of BNNS on the gas barrier and mechanical properties of the PEF composites.…”

“…The addition of BNNS can improve the thermal stability of polymer composites, reducing the risk of thermal degradation at elevated temperatures . The incorporation of BNNS can lead to improvements in the mechanical properties of polymers, including tensile strength, modulus, elongation at break, and toughness. , Furthermore, BNNS can exhibit good compatibility with the polymer matrix, leading to improved interfacial adhesion . This compatibility is crucial for achieving a homogeneous dispersion of BNNS within the polymer matrix and improving the barrier properties of polymer. , However, the modifiers must also simultaneously meet the growing requirements for green sustainability, superior dispersion, and film formation owing to the inferior film-forming properties of BNNS.…”