Hydroxyethyl cellulose

Hydroxyethyl cellulose (CAS 9004-62-0), commercially known as Natrosol or HEC, is a water-soluble polymer derived from cellulose; used primarily as a thickener and rheology modifier.

Where is Hydroxyethyl cellulose used?

• Architectural and industrial coatings: controls sag resistance
• Coatings: improves brush drag, affecting application quality and shelf stability
• In coatings, provides good leveling.
• Construction: in tile adhesives, cement renders and joint compounds to extend open time and improve workability
• Personal care: thickens shampoos, lotions and topical gels, contributing moisture retention
• In shampoos, conditioners and hair styling products, acts as a mild thickener that improves viscosity, foam stability and even application with easy rinsing.
• In skin care products such as creams, lotions and gels, creates a smooth non-sticky feel, stabilizes emulsions and improves moisture retention on the skin.
• Pharmaceutical: Cellosize-grade material in ophthalmic solutions and tablet coatings
• It builds viscosity in aqueous systems without heat activation.
• With a certain molar substitution degree, catalyzes and protects colloidal polymerization in latex polymerization.

Good to know: Grades include low, medium and high viscosity. Recognized specifications include USP, Ph. Eur. and technical grades; food-contact and cosmetic-compliant variants exist.

Formulation notes

• Dosage is generally between 0.1 and 2% of the total weight of the formulation.
• Incompatible with zein and partially compatible with casein, gelatin, methylcellulose, polyvinyl alcohol, and starch.
• Unlike hydroxypropyl methylcellulose (HPMC), it is non-ionic, used mainly in water-based systems and does not have thermal gelling properties.

Typical specification

• Nonionic polymer that is compatible with ionic polymers, surfactants and salts.
• Viscosity of a 2% aqueous solution measured with NDJ at 20°C is 300 to 200000 mPa·s.
• Stable over a pH range of generally 2 to 12.
• Low-molecular-weight grades give near-Newtonian rheology suitable for applications requiring stable viscosity at any shear.
• High-molecular-weight grades show non-Newtonian pseudoplastic rheology.

Regulatory status

• Listed in the Cosmetics Ingredient Review (CIR).
• Semi-synthetic, derived from natural cellulose but chemically modified, and suitable for vegan and cruelty-free products.
• Not approved for direct use in food products in the EU or the US, but permitted for indirect applications such as packaging.

Frequently asked questions about Hydroxyethyl cellulose

How should hydroxyethyl cellulose powder be added to water?

The powder should be added slowly to water under high-speed mixing to prevent lumping.

What forms and grades of hydroxyethyl cellulose are available?

It is supplied as a stable, free-flowing fine powder that dissolves easily in cold or hot water, and is available in various grades with different degrees of viscosity and substitution.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.