Hydroxypropyl Methyl Cellulose

HPMC is a non-ionic cellulose ether produced by alkali treatment of refined cotton linters or wood pulp, followed by etherification with propylene oxide and chloromethane. Its molecular structure contains both hydroxypropyl and methoxy groups, endowing the product with excellent cold-water solubility, thermal gelation properties, and pH stability. In coatings, HPMC primarily serves as a thickener, water-retaining agent, and rheology modifier, providing a smooth application experience and a stable coating film structure.

Product Description

HPMC is a non-ionic cellulose ether produced by alkali treatment of refined cotton linters or wood pulp, followed by etherification with propylene oxide and chloromethane. Its molecular structure contains both hydroxypropyl and methoxy groups, endowing the product with excellent cold-water solubility, thermal gelation properties, and pH stability. In coatings, HPMC primarily serves as a thickener, a water-retaining agent, and a rheology modifier, providing a smooth application experience and a stable coating film structure.

Technical Parameters

 

Methoxy content	19.0–30.0%
Hydroxypropyl content	4.0–12.0%
Viscosity range (2% aqueous solution, 20°C)	1,000–200,000 mPa·s
Gel temperature	50–90°C (adjustable)
pH value	5.0–8.0
Ash content	≤1.5%
Loss on drying	≤5.0%
Particle size distribution	80-mesh pass rate ≥ 98% (customizable fineness)

 

Application Highlights

Architectural coatings: Offer excellent sag resistance and open time, suitable for thick-paste textured coatings.

Putty and plaster mortar: Enhance water retention, prevent cracking, and improve bonding strength.

Tile adhesive: Enhances slip resistance and adjusts setting time.

Complies with international standards: Meets specifications such as ASTM C387 and EN 934, and is suitable for eco-friendly formulations (low VOC, APEO-free).

 

Engineer’s Summary: Product Selection Guide

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, pronounced shear-thinning behavior, and excellent construction performance.
High-salt-resistant environment (exterior wall coating)	HPMC/HEMC	Nonionic, pH-resistant from 4 to 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.