Competition between Hydrogen Bonding and Dispersion Force in Water Adsorption and Epoxy Adhesion to Boron Nitride: From the Flat to the Curved

Abstract

Hexagonal boron nitride (h-BN) is a material with excellent thermal conductivity and electrical insulation, used as an additive to various matrices. To increase the affinity of h-BN to them, hydrogen bonds should be formed at the interface. In reality, however, they are not formed; the N atoms are not capable of accepting hydrogen bonds due to the delocalization of their lone pair electrons over the B–N π bonds. To make it form hydrogen bonds, one may need to break the planarity of h-BN so that the orbital overlap in the B–N π bonds can be reduced. This idea is verified with first-principles calculations on the adsorption of a water molecule on hypothetical h-BN surfaces, the planarity of which is broken. One can do it in silico but not in vitro. BN nanotubes (BNNTs) are considered as a more realistic BN surface with nonplanarity. The hydrogen bond is shown to become stronger as the curvature of the tube increases. On the contrary, the strength of the dispersion force acting at the interface becomes weaker. In water adsorption, these two interactions are in competition with each other. However, in epoxy adhesion, the interaction due to dispersion forces is overwhelmingly stronger than that due to hydrogen bonding. The smaller the curvature of the surface, the smaller the distance between more atoms at the interface; thus, the interaction due to dispersion forces maximized.

Capsaicin-Modified Fluorosilicone Based Acrylate Coating for Marine Anti-Biofouling

“…In addition, the reason for the higher adhesion of hybrid coatings on steel surface than on glass is that the steel surface has more hydroxyl groups, which can form more hydrogen bonds with the hybrid coatings. More importantly, all the hybrid coatings still showed excellent adhesion performance after 30 days of immersion in ASW (Artificial seawater configured according to ASTMD1141-98 standard), similar to the values measured before immersion, proving that all the coatings have stable adhesion performance in the marine environment [27,28].…”

The wetting‐to‐nonwetting transition of CVD BN coatings deposited at different temperatures

“…Iannuzzi and coworkers 12,13 studied the superstructure of single‐layer h‐BN on transition metals and proposed that N atoms in h‐BN could form hydrogen bonds with water, but the binding energies are much weaker than the interactions between water molecules themselves; corrugated h‐BN/Rh(111) is slightly more hydrophilic than flat h‐BN/Rh(111) 14 . Tsuji and Yoshizawa 15 demonstrated the difficulty of N atoms in h‐BN to accept hydrogen bonds due to the delocalization of lone pair electrons over the π bonds by calculation; if curvature exists to break up the planarity of h‐BN as in the case of boron nitride nanotube, the hydrogen bonds become stronger and the hydrophilicity increases.…”

The Improved Antiwear and Anticorrosion Properties of Epoxy Resin with Metal–Organic Framework ZIF-8 Containing Lubrication Oil

“…Polymer nanocomposites have been widely used in aerospace, marine, and biomedical applications because of their excellent mechanical and lubricating properties. − Epoxy resin-based nanocomposites usually exhibit better self-lubrication performances by adding functional nanofillers, such as soft metal, oxidizing material, fluorides, and two-dimensional layered materials. − In addition to self-lubrication materials, solid–liquid compound lubrication is another important and effective way to reduce the coefficient of friction (COF) and wear rate . However, solid–liquid compound lubrication is not suitable for applications where external lubrication is not allowed.…”