Nanocellulose ( Nanocellulose ) is a new type of functional material obtained from natural cellulose through nano-processing. It is being widely used in daily chemicals, food, medicine and functional materials industries because of its renewable, safe and environmentally friendly, high stability and other advantages. Among them, ' strong suspension ability, high transparency and excellent thixotropy ' have become one of the most industrially valuable properties of nanocellulose. This article will provide an in-depth introduction to the suspension effect of nanocellulose in the formulation system from the aspects of microstructure, rheological mechanism, application effect and engineering practice .

1. Microscopic mechanism of nanocellulose suspension ability

Nanocellulose (mainly including CNF 、CNC 、BC ) is usually between 3–20 nm in diameter and can reach hundreds of nanometers to several micrometers in length. The high aspect ratio and high specific surface area enable it to form a three-dimensional nanonetwork structure ( 3D Network ) in water . The network achieves levitation through the following mechanisms:

1. Three-dimensional physical entangled structure enhances system support

CNF filaments form a stable skeleton through entanglement, hydrogen bonding and van der Waals interactions, generating initial yield stress, which can effectively support suspended particles.

2. Surface carboxyl groups and charges improve dispersion

The surface of nanocellulose treated with TEMPO oxidation or sulfuric acid hydrolysis is charged, forming a stable charge repulsion layer ( Electrical Double Layer ) to inhibit particle sedimentation and aggregation.

3. Thixotropy achieves 'no sinking when left standing and smooth use'

When left standing, the network structure is stable and can lock pearlescent flakes, plant particles, etc.; when sheared, the network is temporarily broken, and the texture is light and non-sticky, improving the user experience.

This series of microscopic effects makes nanocellulose an excellent structural reinforcement material that can achieve long-term stable suspension with low addition amount .

2. Technical advantages of nanocellulose in formula systems

1. High transparency, does not affect appearance

The nanometer diameter brings low light scattering, allowing nanocellulose to maintain a light transmittance of ≥85% in systems such as transparent shower gel and transparent essence.

2. Strong suspension ability, particles will not settle or float

An effective solid content of about 0.2–1.0% can lift 1–100 μm particles, including:

Pearlescent particles

plant microparticles

Functional microcapsules

Fragrance particles

3. Safety, environmental protection and sustainability

It is of natural origin, conforms to the trend of sustainable consumption, and is suitable for food, daily chemicals, and environmentally friendly products.

4. Mild rheology adjustment without significantly increasing system viscosity

Different from traditional ' thickening suspension agents ' , nanocellulose mainly builds a network rather than simply increasing the viscosity, so it does not cause the disadvantages of being thick, sticky, and stagnant.

3. Rheological indicators: core parameters for judging suspension effect

In order to accurately evaluate suspension capability in research and development, the following rheological parameters can be focused on:

test items	Index meaning	Typical target values ​​(transparent shower gel reference)
Yield Stress	Evaluate the ability to 'lift particles'	10–50Pa
zero shear viscosity	Static viscosity affects suspension stability	100–2000 mPa·s
G'/G'' (storage modulus/loss modulus)	Determine whether a network is formed	G'>G''
thixotropic recovery curve	Can it be quickly recovered after shear damage?	The higher the recovery rate, the better

Rheological patterns can effectively determine whether the formulation system is sufficient to stabilize suspended particles.

4. Application Scenario: Nanocellulose Suspension Solution

As a suspending agent, nanocellulose has been used in many industries:

1. Daily chemical industry (key)

Transparent shower gel : suspended pearlescent sheets, plant particles, functional microcapsules

Shampoo, conditioner : stabilized oil droplets and nutritional particles

Transparent hand sanitizer : maintain stable dispersion under high light transmittance

2. Food Industry

Improve the stability of the beverage system and prevent the pulp from settling or stratifying.

3. Agrichemical and pharmaceutical preparations

Improve the uniform distribution of active ingredient particles and improve usage efficiency.

5. Examples of typical transparent shower gel formulas (for research and development reference)

Element	Dosage ( wt%)	Function
Deionized water	65–75	matrix
Table activities such as SLES / APG	10–14	Cleansing and foaming
Cocamidopropyl Betaine	2–4	mild sexual conditioning
Glycerin /propylene glycol	2–4	Moisturize and improve skin feel
Nanocellulose CNF	0.2–1.0 (discount included)	suspended /reinforced structure
Plant microparticles /pearl flakes	0.1–1	floating object
Flavors, preservatives, pH adjusters	Appropriate amount	conventional

Note: ·
The recommended order of adding CNF is water phase → surface active system → CNF → high shear dispersion → adding particles → adjusting system 。
· If higher transparency is pursued, CNF or CNC/CNF blending system with narrower particle size distribution can be used .

6. Key points of engineering and stability verification

Stability tests that require focus include:

Centrifugal stability ( 3000–5000 rpm )

40℃/6 months accelerated aging

Cryogenic Freeze – Thaw Cycle

Vibration / Transportation Simulation Testing

Zeta potential and particle size change monitoring

Frequently asked questions and solutions:

The cationic surface activity is too high → network collapse
, select some anionic CNF or perform surface grafting

Decreased transparency → increased light scattering
selects finer fibers and reduces agglomeration (high shear homogenization)

The system becomes thinner or stratified → insufficient network
to improve effective inclusion or select modified CNF

7. Conclusion: Nanocellulose will become the core of a new generation of green suspension technology

With its high stability, sustainability, high transparency and controllable rheological structure, nanocellulose has become a highly competitive new suspension material in the daily chemical and food industries. As the industrialization of nanocellulose continues to increase, its role as the ' next generation green suspending agent ' will become increasingly important.