Nanocellulose surface modification based on TEMPO oxidation and its application in composite materials

1. Introduction to TEMPO oxidized nanocellulose

Tempo oxidized nanocellulose is a nanomaterial extracted from natural cellulose by TEMPO oxidation. This method can effectively introduce carboxyl groups, so that the nanocellulose can exhibit good dispersion and reactivity in aqueous solution. In addition, TEMPO oxidation treatment imparts higher specific surface area and better mechanical properties to cellulose nanofibers, giving them the potential to enhance composite materials.

2. Surface modification method of TEMPO oxidized nanocellulose

To enhance the application effect of TEMPO oxidized nanocellulose in composite materials, it is often necessary to surface modification. Commonly used surface modification methods include the following:

Chemical grafting : By introducing different functional groups, such as amino, hydroxy or amide groups, strong chemical bonds can be formed with the matrix material, thereby increasing the binding force between the nanocellulose and the composite matrix.

Physical adsorption : Using the physical adsorption effect between molecules, specific molecules or polymers, such as surfactants or biological macromolecules, can be adsorbed on the surface of .Tempo oxidized nanocellulose , thereby changing its surface characteristics and improving compatibility with composite materials.

Polymer composite modification : Combining nanocellulose with polymers, such as polyvinyl alcohol (PVA), polylactic acid (PLA), etc., can make it form good interface compatibility with other substrates when the material is composited, thereby improving Stability of composite materials.

Inorganic nanoparticle modification: loading inorganic nanoparticles such as zinc oxide (ZnO) and titanium dioxide (TiO₂) on the surface of nanocellulose can improve their photoelectric properties, antibacterial properties, etc., thereby expanding their application in multifunctional composite materials.

III. Application of TEMPO oxidized nanocellulose in composite materials

High-strength composite materials: TEMPO oxidized nanocellulose can be added to polymer matrix as reinforcement materials, such as polypropylene (PP), polyethylene (PE), etc., which greatly improves the strength and rigidity of composite materials. It is suitable for automobiles and aviation. and other fields.

Environmentally friendly packaging materials: By composited with degradable polymers (such as PLA), Tempo oxidized nanocellulose can improve the mechanical properties and water resistance of the material, making it an ideal green and environmentally friendly packaging material.

Medical composites: TEMPO oxidized nanocellulose has good biocompatibility and can be used as a drug carrier or for tissue engineering scaffolds after surface modification to help achieve sustained release and targeted delivery.

Conductive composite materials: By modifying conductive materials (such as graphene or carbon nanotubes) on the surface of TEMPO oxidized nanocellulose, composite materials with excellent conductivity can be obtained, which are widely used in electronic equipment and sensor fields.

Barrier composite materials: TEMPO oxidized nanocellulose has good nanobarrier characteristics. By composited with other barrier materials, it can be used in moisture-proof and gas-proof packaging materials to improve the barrier effect.

4. Future development prospects of TEMPO oxidized nanocellulose composite materials

With the increase in environmental awareness and the increase in demand for high-performance materials, Tempo oxidized nanocellulose has broad application prospects in the field of composite materials. By further optimizing the surface modification technology, it can accurately control its performance, making its application effect more excellent in different composite materials. In addition, with the advancement of production processes and the reduction of costs, TEMPO oxidized nanocellulose will become more popular in industrial production and application.

The surface modification of Tempo oxidized nanocellulose significantly improves its application potential in composite materials. Through suitable modification methods, TEMPO oxidized nanocellulose can form a stable interface with various matrix materials, improving the mechanical properties, thermal stability and functionality of the composite material. In the future, in the fields of environmentally friendly materials, pharmaceutical materials and electronic equipment, the surface modification of TEMPO oxidized nanocellulose and the application of composite materials will usher in greater development space.