1. Introduction

Suspending Agent plays a key role in coatings, food, medicine, pesticides and daily chemical products. It is used to stabilize the uniform dispersion of solid particles in liquids and prevent settlement or aggregation. Traditional suspension agents are mostly synthetic polymers or inorganic clay substances, but they have problems such as poor biodegradability, heavy environmental burden or low system transparency .

Nanocellulose , as a natural and renewable functional material, has gradually become a research hotspot for the new generation of green suspension agents due to its high specific surface area, excellent rheology regulation ability and suspension stability .

2. The mechanism of action of nanocellulose suspension function

Network structure support effect

The nanocellulose has a high aspect ratio (diameter 5–50 nm , length up to several microns), which can form a three-dimensional physical network in the aqueous phase, increase the system viscosity and yield stress, and effectively inhibit particle settlement.

Static electrostatic and steric resistance stability

The surface of nanocellulose modified by TEMPO oxidation or carboxymethylation is negatively charged, and the electrostatic repulsion between particles cooperates with the spatial hindrance of the fibers to improve dispersion stability.

Thixotropy and shear dilution

The nanocellulose suspension forms a gel-like structure when left to stand to prevent settlement, and increases fluidity during stirring or pumping, which facilitates processing and coating.

3. Performance advantages

Renewable and degradable : natural source, green and environmentally friendly production process

High transparency : It does not affect the appearance of the system, can be used in transparent or translucent products

High temperature and pH stability : After modification, it can be maintained at wide pH ( 3–11 ) and medium and high temperatures.

Low dosage and high efficiency : Mass fraction 0.1–0.5% can significantly improve suspension stability

Good compatibility : can be used with a variety of surfactants, polymers and inorganic fillers

4. Typical application areas

Application areas	Mechanism and Advantages	Sample recipe
Paint ink	Suppress pigment settlement and improve construction leveling	CNC + Water-based Acrylic Coatings
Food and beverage	Stabilize juice or function microcapsule suspension	CNC + Juice Drink (Transparent)
Pharmaceutical preparations	Stable and insoluble drug particles to improve taste and appearance	CNC + Suspended Oral Liquid
Pesticide preparations	Prevent active ingredients from settled and improve spray uniformity	CNC + Water Suspension (SC)
cosmetic	Maintain pigment or pearl powder to improve skin feeling	CNC + sunscreen spray/liquid foundation

5. Reference for experimental performance data (typical results)

CNC addition amount (mass fraction)	System Type	Viscosity (mPa·s, 25℃)	Sedimentation rate *(30 days)*	Light transmittance (% @550 nm)
0%	Pigment water dispersion	20	85%	92
0.1%	Pigment water dispersion	120	20%	91
0.3%	Pigment water dispersion	420	0%	90
0.5%	Juice drinks	250	0%	93
0.5% (TEMPO modification)	Pesticide water suspension agent	310	0%	89

Data description:

Settlement rate = Settlement height/Initial height × 100%

After adding nanocellulose, the low addition amount can significantly inhibit the sedimentation

The light transmittance remains above 90%, and the system has good transparency in appearance

6. Development trends and challenges

trend

Functional suspension agent : at the same time imparts antibacterial, anti-ultraviolet rays, sustained release and other functions

Multiphase synergistic system : Compounded with natural polysaccharides, proteins or nanoclays to enhance suspension stability

Industrialized low-cost preparation : improve dispersion efficiency and reduce energy consumption

challenge

Stability under high salt and high organic solvent systems

Prevent architecture aging or fiber agglomeration during long-term storage

Customized surface modification is required in different systems

7. Conclusion

As a suspension agent, nanocellulose has shown broad application prospects in coatings, food, medicine, pesticides, daily chemicals and other fields due to its high specific surface area, excellent rheology regulation capabilities and green and sustainable characteristics. With the continuous improvement of modification technology and dispersion processes, its market potential in high-end refined industries will be further released.