HEC Thickening and Suspension Applications in Daily Chemical Products

Hydroxyethyl cellulose (HEC), a non-ionic cellulose ether, is widely used in daily chemical products, including shampoos, shower gels, hand sanitizers, facial cleansers, and household cleaners, due to its good water solubility, strong compatibility, non-irritation, and excellent thickening and suspension properties. Its core functions mainly focus on thickening, stabilization, suspension, and rheological regulation, making it an irreplaceable structural additive in modern daily chemical formulations.

Thickening Mechanism and Advantages of HEC

HEC can rapidly swell and dissolve in water, forming a transparent and homogeneous viscoelastic solution. Its thickening effect mainly occurs through the formation of a three-dimensional structural network by hydrogen bonds between cellulose molecular chains, thereby increasing the system viscosity. Compared to other thickeners, HEC has the following advantages in the daily chemical field:

1.1. Mild and Stable Thickening Effect

HEC is not significantly affected by the system's pH, exhibiting good thickening effects within a pH range of 4–10, making it suitable for the weakly acidic or neutral formulations of most daily chemical products.

1.2. High Transparency, Suitable for Transparent Systems

Highly substituted HECs have excellent water solubility, resulting in clear and transparent finished products, making them particularly suitable for transparent shampoos, transparent shower gels, and hand sanitizer gels.

1.3. Adjustable Rheology

By selecting different viscosity grades of HEC, the following can be achieved:

1.4. High Low Shear Viscosity → Creates a "wall-hanging" feel

Moderate High Shear Viscosity → Easy to squeeze out and spread during use. This is especially important in shampoos and hand sanitizers.

1.5. Gentle Skin and Hair Feel

HECs improve the smoothness of products, making washing and skin care products feel more delicate and smooth, without causing irritation or dryness.

Suspension and Stabilization Effects in Daily Chemical Products

2.1. Suspended Microparticles, Pearlizing Agents, and Exfoliating Particles

Pearlizing agents, colored particles, and exfoliating particles are often added to shampoos and shower gels to achieve visual effects. HEC increases the low-shear viscosity of the system, ensuring uniform particle distribution and preventing sedimentation.

2.2. Improves the stability of surfactant systems

Most daily chemical products are complex systems of multiple surfactants. Adding HEC can enhance the viscoelastic structure of the system, improving its resistance to stratification and water separation.

2.3. Improves the emulsion stability of oil-water systems

In weakly emulsified systems such as facial cleansers and makeup removers, HEC helps emulsifiers form a more stable O/W structure, preventing oil from rising or separating.

2.4. Enhances foam stability

In shampoos and shower gels, HEC, through thickening and interfacial stabilization, makes the foam finer and longer-lasting, improving the user experience.

Specific Applications of HEC in Typical Daily Chemical Products

Shampoo and Shower Gel: Thickening system, creating good rheological properties; Suspending pearlescent agents and plant extract particles; Improves skin feel and foam quality.

Hand Sanitizer (including no-rinse disinfectant gel): Forms a transparent gel texture; Improves product smoothness and ease of use.

Facial Cleanser and Skin Care Products: As a co-emulsifier and stabilizer; Improves spreadability and suspension; Provides a gentle skin feel and is non-irritating.

Household Cleaners (such as glass cleaner and kitchen cleaner): Enhances product adhesion and residence time; Ensures uniform suspension of particulate additives; Improves the rheology of spray products.

Precautions for Use

4.1. Proper Dissolving Method

HEC should be added gradually to water under high-speed stirring to avoid clumping; delayed-dissolving HEC can also be used to improve operational efficiency.

4.2. Dosage Control

Common dosage ranges in daily chemical products:

Shampoo, Shower Gel: 0.3%–1.0%

Hand Sanitizer, Cleanser: 0.2%–0.8%

Facial Cleanser, Skin Care Products: 0.1%–0.5%

4.3. Compatibility with Surfactants

As a nonionic thickener, HEC is compatible with anionic, amphoteric, and nonionic surfactants. However, it should be noted that excessive salt content may affect viscosity.