Nanocellulose is a nano-scale structural material obtained by using natural cellulose as raw material and processed through physical, chemical or enzymatic methods According to its morphology and preparation method, nanocellulose is mainly divided into three categories: . cellulose nanocrystals ( CNC ) 、, cellulose nanofibers ( CNF ) and bacterial nanocellulose ( BNC ) . This type of material combines the advantages of ' high performance ', ' renewable ', ' environmental protection ' , and is a hot topic in the research and application of contemporary green polymer materials.

This article will conduct in-depth analysis of the key properties of nanocellulose from six aspects:

1. High mechanical properties: high strength and high modulus coexist

The molecular chain of nanocellulose contains a large amount of β-1,4- glycosidic bonds , and its rigid structure imparts excellent mechanical properties. Research shows that:

Tensile strength : The tensile strength of nanocellulose monofilament can reach 2 GPa；

Young's modulus : up to 1001.6 g/cm³；

Enhancement effect : Adding it to polymers or resins can significantly improve the tensile strength and fracture toughness of the composite material, showing good reinforcement effect.

This performance makes nanocellulose have great potential in aerospace, automobile manufacturing, building composite materials and other fields, and is highly favored as a green alternative reinforcement material.

2. Excellent biodegradability and environmental friendliness

Nanocellulose is derived from plant fibers or microorganisms in nature and does not contain any toxic and harmful ingredients . In soil or water, it can be degraded into carbon dioxide and water by microorganisms such as fungi and bacteria, and will not form lasting pollutants.

This performance is especially suitable for use scenarios such as biodegradable plastics, food packaging films, disposable medical supplies, etc., and is in line with the current environmental protection concept of ' carbon neutrality' and ' sustainable development ' .

3. Strong biocompatibility: suitable for medical and tissue engineering

Due to the good biocompatibility of nanocellulose, there will be no rejection or toxic side effects when in contact with biological tissues. This makes it widely used in the field of medical materials:

Wound dressing : can provide a humid environment, absorb exudate, and promote tissue regeneration;

Drug carrier : rich surface functional groups, adsorbing and embedding drugs, achieving sustained release effect;

Cell culture substrate : three-dimensional nanonetwork structure is conducive to cell attachment and growth;

Artificial tissue scaffold : It has both mechanical support and biological activity, and is suitable for regeneration engineering such as bone tissue and cartilage.

4. Good suspension stability and rheological performance

Due to its large specific surface area and a large number of hydroxyl groups on the surface, nanocellulose can fully combine with water molecules to form a stable colloidal system in water:

It exhibits a gel-like structure at low concentrations;

Significantly improve the viscosity and rheological performance of the system;

Shows shear thinning behavior, which facilitates pumping and coating processing.

Therefore, it is widely used as a thickener, suspending agent, stabilizer and film forming agent , and is especially suitable for use in product systems such as emulsions, coatings, cosmetics, 3Dprinting hydrogels, etc.。

5. High specific surface area and strong adsorption capacity

The diameter of nanocellulose is usually 5–50 nanometers and has a high aspect ratio, which can form a three-dimensional network structure, making its surface area per unit mass very large (up to hundreds of m²/g ). This structural feature makes it have the following properties:

High water absorption rate : It can absorb several times to tens of times its own mass of water;

Good adsorption : It can be used for adsorption treatment of heavy metal ions, dyes, organic pollutants, etc.;

Energy storage material carrier : suitable as a porous skeleton or electrolyte film carrier for lithium battery electrodes.

6. Rich surface functional groups, easy to chemically modify

The surface of nanocellulose contains a large number of hydroxyl ( –OH ) groups, which can achieve various functional modifications through chemical reactions such as esterification, etherification, and oxidation, such as:

Modification method	Modification results	Application direction
TEMPO oxidation	Introduce carboxyl groups to improve hydrophilicity and metal ion adsorption capacity	Adsorbent materials, hydrogels
Acid chloride reaction	Enhance hydrophobicity and improve dispersion	Combined with non-polar polymers
Graft polymerization	Give electrical conductivity, antibacteriality, pH responsiveness and other functions	Smart materials, sensors

This ' customizable ' feature makes nanocellulose an ideal platform for functional material development。

Summarize

Nanocellulose has both structural advantages and environmental protection properties, and has the following outstanding properties:

High strength, light quality

Degradable, non-toxic

Good biocompatibility

Excellent water dispersion and rheology properties

Large surface area and strong adsorption capacity

Surface modification and functional diversity

With the continuous optimization of its preparation process and the gradual reduction of costs, nanocellulose will play an increasingly important role in medical materials, functional coatings, high-performance composite materials, flexible electronic devices, green packaging and other fields.