Fabrication and Characterization of Hydrophobic Cellulose Nanofibrils/Silica Nanocomposites with Hexadecyltrimethoxysilane

Abstract

Cellulose nanofibrils (CNFs) have attracted much attention because of their renewability and potential biocompatibility. However, CNFs are extremely hydrophilic due to the presence of a large number of hydroxyl groups, limiting their use as a water-resistant material. In this work, we controlled the adsorption behavior of silica nanoparticles on the surface of CNFs by adjusting the synthesis conditions. The silica nanoparticle size and packing efficiency on the CNF surface could be controlled by varying the ammonium hydroxide and water concentrations. In addition, hexadecyltrimethoxysilane (HDTMS) was successfully grafted onto CNF or CNF/silica nanocomposite surfaces, and the quantitative content of organic/inorganic substances in HDTMS was analyzed through XPS and TGA. The HDTMS-modified CNF/silica nanocomposites were more advantageous in terms of hydrophobicity than the HDTMS-modified CNF composites. This is because the silica nanoparticles were adsorbed on the surface of the CNFs, increasing the surface roughness and simultaneously increasing the amount of HDTMS. As a result, the HDTMS-modified CNFs showed a water contact angle (WCA) of ~80°, whereas HDTMS-modified CNF/silica nanocomposites obtained superhydrophobicity, with a WCA of up to ~159°. This study can provide a reference for the expansion of recyclable eco-friendly coating materials via the adsorption of silica nanoparticles and hydrophobic modification of CNF materials.

Superhydrophobic Polyurethane Membrane with a Biomimetically Hierarchical Structure for Self-Cleaning

“…The peaks at 531.65, 532.8, and 534.5 eV belong to CONH, C–O–Si, and OCOO, respectively, which is illustrated in Figure c. Figure d exhibits the Si–C and Si–O–C peaks, which are located at 100.8 and 102.5 eV . It can be seen from X-ray photoelectron spectroscopy (XPS) that the addition of HDTMS is only physical mixing and does not make it generate new chemical bonds, which is consistent with the infrared results.…”

“…Si−O−C peaks, which are located at 100.8 and 102.5 eV. 34 It can be seen from X-ray photoelectron spectroscopy (XPS) that the addition of HDTMS is only physical mixing and does not make it generate new chemical bonds, which is consistent with the infrared results.…”

Superhydrophobic and superlipophilic LDH flower balls/cellulose membranes for efficient oil–water separation

“…32,33 Compared to the unmodified LDH/cellulose film, the modified LDH/cellulose film IR spectrum shows a peak at 650 cm À1 for the Si-O bond and a peak near 2900 cm À1 for the symmetric and asymmetric stretching vibrations of the CH 2 long chain of HDTMS. 34 This demonstrates that HTDMS has been grafted onto the surface of the membrane and successfully modified the LDH/cellulose membrane with superhydrophobicity.…”

Chemically Engineered Microporous Layer with Superhydrophobicity for High-Performance Proton Exchange Membrane Fuel Cells

“…Evident from Figure S2’s comprehensive spectra, SP-HDTMS diverges from pristine SP, marked by succinct Si 2s and Si 2p resonances at 154 and 103 eV, underscoring HDTMS’s integration. Figure b elucidates the C 1s realm for native SP, segmenting signals into quartets reflective of intrinsic configurationsC–C (284.8 eV), C–CO (285.9 eV), C–O (286.8 eV), and O–CO (289.5 eV). ,− Transitioning to SP-HDTMS, the spectrum expands, introducing vibrations at 283.5 and 285.5 eV, resonating with C–Si and C–O–Si structures, thereby authenticating HDTMS’s covalent adhesion.…”