Preparing Hydrophobic Cellulose Nanofibers-SiO2 Films and Coating by One-Step Mechanochemical Method

Abstract

Green and sustainable cellulose-based hydrophobic coatings are increasingly the subject of scientific and industrial research. However, few researchers pay attention to preparing it by a one-step method. Therefore, a superhydrophobic coating composed of hydrophobic SiO2 and cellulose nanofiber modified by 3,4-dichlorophenyl isocyanate was manufactured through one-step ball milling. It was found that the ball milling can promote SiO2 dispersion and achieve the preparation of modified nanocellulose, which further disperse SiO2 nanoparticles to form film or coating. Compared with the ultrasonic dispersion method, the composite coating prepared by ball milling method can obtain higher water contact angle and more stable hydrophobic properties. The hydrophobic cellulose nanofiber can load 1.5 equivalents of SiO2 nanoparticles to form a uniform film with the water contact angle of 158.0° and low moisture absorption. When this nanocomposite is used as a coating material, it can impart super-hydrophobicity to paper surface with water contact angle of 155.8°. This work provides a facile way to prepare superhydrophobic nanocellulose/nanoparticles composite coatings and films, thereby broadening the ways of dispersing nanoparticles and constructing superhydrophobic coatings.

Nanocellulose, a Renewable Biobased Functional/Reinforcement Additive for Composite Coating Materials: A Review

“…Chen et al 51 fabricated a CNF/SiO 2 nanoparticle composite by using CNF, 3,4-dichlorobenzene-isocyanate, and SiO 2 through defibrillation, hydrophobic modification, and ball milling. They prepared a hydrophobic CNF/SiO 2 nanoparticle composite and then coated it onto the surface of kraft paper to form a hydrophobic coating surface.…”

Nanocellulose Grades with Different Morphologies and Surface Modification as Additives for Waterborne Epoxy Coatings

“…These issues strongly depend on the morphology and percolation threshold of nanocellulose [ 39 ]. The surface modification is not prioritized to improve compatibility in waterborne systems, but it may reduce the viscosity and increase the dispersible volume fraction [ 40 ], while bringing additional functionality such as encapsulation and the controlled release of active ingredients [ 41 ], hydrophobicity [ 42 ], stabilization [ 43 ], or anti-microbial properties [ 44 ].…”