What is the hydrophobicity of boron nitride nanotubes?5 answersBoron nitride nanotubes (BNNTs) exhibit high hydrophobicity, with a wide range of wetting properties from superhydrophilicity to superhydrophobicity. Highly-rough vertical-to-substrate nanotube and nanosheet patterns demonstrate great water-repellency, while conical nanostructures are less hydrophobic. Noncovalent functionalization of BNNTs with water-soluble synthetic polymers enhances their hydrophobicity and enables the creation of superhydrophobic surfaces. BNNTs are valued for their high hydrophobicity, among other physicochemical properties, and are being investigated for a wide range of applications including drug delivery, biomaterials, and neutron capture therapy.
Why do hydrophobic polymers stick to each other?5 answersHydrophobic polymers stick to each other due to the hydrophobic interaction. This interaction is caused by the exclusion of water molecules from the polymer surfaces, leading to the formation of a cohesive force between the hydrophobic regions of the polymers. The hydrophobic interaction is influenced by factors such as the presence of dissolved gases in the surrounding solution. The range of the hydrophobic interaction can be affected by the concentration of electrolytes in the solution. Additionally, the adhesion properties of hydrophobic polymers can be improved through the use of plasma treatment, which enhances the bondability of these materials. Plasma technology allows for the repair and fabrication of highly water-resistant materials, leading to cost savings and improved durability of naval hardware applications.
Does hydrophobicity affect corrosion resistance?5 answersHydrophobicity has been found to significantly affect corrosion resistance in various materials. In the case of petroleum pipelines, the addition of a hydrophobic fluorocarbon chain oil to an epoxy coating improved its hydrophobic, wear-resistant, and corrosion-resistant properties. Similarly, the formation of a super-hydrophobic coating on magnesium alloys enhanced their anti-corrosion performance by retarding corrosion damage. The hydrophobicity of self-assembled films on a microarc oxidation (MAO) film on magnesium alloy also influenced the corrosion resistance of the composite coatings, with more hydrophilic films providing better protection. Additionally, the creation of a hydrophobic steel surface through electro-etching improved corrosion resistance by increasing polarization resistance and decreasing corrosion current density. Finally, the preparation of surface textured epoxy resin coatings with improved hydrophobicity showed excellent corrosion resistance, with the texture parameters consistently affecting both properties.
How does hydrophobicity affect corrosion resistance?5 answersHydrophobicity has a significant impact on corrosion resistance. In the case of magnesium alloys, the hydrophobic self-assembled layer on the microarc oxidation (MAO) film affects the morphology and thickness of the electroless nickel (EN) layer, ultimately influencing the corrosion resistance. Similarly, the formation of a super-hydrophobic coating on the surface of magnesium-lithium alloys improves their anti-corrosion performance by retarding corrosion damage. For steel surfaces, the hydrophobicity achieved through electro-etching techniques enhances corrosion resistance by increasing the polarization resistance and decreasing the corrosion current density. In the case of epoxy coatings, the addition of a hydrophobic fluorocarbon chain oil improves the hydrophobic, wear-resistant, and corrosion-resistant properties, making it suitable for oil pipeline transportation. Finally, the super-hydrophobicity achieved through laser surface texturing and duplex treatment enhances the corrosion resistance of stainless steel by creating micropores and increasing the contact angle.
Why amphipathic peptides are used to study aggregation beta sheet?4 answersAmphipathic peptides are used to study the aggregation of beta sheets because they have a high propensity to self-assemble into β-sheet fibrils. These peptides are composed of alternating hydrophobic and hydrophilic amino acids, which allows for the formation of β-sheet bilayer structures. The hydrophobic amino acids in the peptide sequence are organized to one face of each constituent sheet, while the hydrophilic amino acids are exposed to solvent. This arrangement of amino acids in the β-sheet bilayer structure promotes the formation of amyloid-like fibrils. By studying the self-assembly of these amphipathic peptides, researchers can gain insight into the fundamental processes and mechanisms of peptide aggregation, which is relevant to understanding amyloid diseases. Additionally, these studies can provide valuable information for the design and development of functional biomaterials based on self-assembled peptide fibrils.
How does addition of rGO affect hydrophobicity?4 answersThe addition of reduced graphene oxide (rGO) affects hydrophobicity by fine-tuning the static water contact angles of metal-organic framework (MOF) microspheres. The hydrophobicity of the MOF microspheres can be adjusted by controlling the crystal size and morphology, and the post-synthetic modification of alkyl chains further enhances the hydrophobicity. The resulting amylamine-modified MOF (AM) microspheres exhibit the strongest hydrophobicity. Additionally, the combination of AM microspheres and rGO can be used to construct a superhydrophobic aerogel for efficient oil-water separation. The AM-rGO aerogel demonstrates fast and efficient absorption of various oily substances from water, with an outstanding oil adsorption capacity that can be maintained even after multiple cycles. Therefore, the addition of rGO to MOF microspheres enhances their hydrophobicity and enables the development of efficient oil-water separation materials.