Hydroxyethyl Methyl Cellulose

HEMC is produced by alkali treatment of cotton linters or wood pulp, followed by reaction with ethylene oxide and chloromethane. Compared to HPMC, HEMC has hydroxyethyl groups introduced into its molecular chain, which significantly enhance its hydrophilicity and dissolution rate. In coatings and construction materials, HEMC exhibits faster dispersibility, higher solution transparency, and better viscosity stability—making it particularly suitable for water-based systems that demand high transparency.

Product Description

HEMC is produced by reacting cotton linter or wood pulp, after alkalization, with ethylene oxide and chloromethane. Compared to HPMC, HEMC features hydroxyethyl groups introduced into its molecular chain, which significantly enhance its hydrophilicity and dissolution rate. HEMC exhibits faster dispersibility, higher solution transparency, and more stable viscosity retention in coatings and construction materials, making it particularly suitable for water-based systems that demand high transparency.

Technical Parameters

 

Methoxy content	14.0–28.0%
Hydroxyethyl content	4.0–15.0%
Viscosity range (2% aqueous solution, 20°C)	500–150,000 mPa·s
Gel temperature	≥65°C
Transmittance (1% solution)	≥90%
Uniformity of substitution degree	MS/DS control accuracy: ±0.05
Bacterial stability	Can be enhanced by HEC-class preservatives

Performance requirements	Recommended Products	Key reason
General-purpose thickening, cost-first	HPMC	High cost performance, and the thermogel properties facilitate thick-film application.
High transparency, rapid dissolution	HEMC	Good light transmission, fast dissolution, suitable for high-gloss systems.
High-end rheological control, anti-splashing	HMHEC	Associative thickening, significant shear-thinning behavior, and excellent construction performance.
High-salt-resistant environment (exterior wall coating)	HPMC/HEMC	Nonionic, tolerant to pH 4–12, with good stability.
Low-VOC and eco-certification requirements	All three apply.	All products are available in solvent-free and formaldehyde-free versions, meeting European and American green standards.