ElitesHost Forums
how HPMC improves the performance of tile adhesives. - Printable Version

+- ElitesHost Forums (https://forum.eliteshost.com)
+-- Forum: Support (https://forum.eliteshost.com/forumdisplay.php?fid=3)
+--- Forum: General Support (https://forum.eliteshost.com/forumdisplay.php?fid=13)
+--- Thread: how HPMC improves the performance of tile adhesives. (/showthread.php?tid=34445)



how HPMC improves the performance of tile adhesives. - hktkljn - 08-19-2025

Role of HPMC in Tile Adhesives
Hydroxypropyl Methylcellulose (HPMC) is the most important polymer additive in cement-based tile adhesives. Although used in very small amounts (≈0.2–0.6%), it dramatically improves performance.

How HPMC Improves Tile Adhesives
1. Water Retention
  • HPMC cellulose ether prevents water from being absorbed too quickly by tiles or substrates.
  • This ensures complete cement hydration, giving stronger bonding.
  • Especially important when working on porous substrates (like AAC blocks, plaster, old concrete) or under hot, dry conditions.

2. Workability & Open Time
  • Provides smooth and creamy consistency, making adhesive easy to mix and spread.
  • Extends open time (the time tiles can be adjusted after adhesive is applied).
  • Reduces drag on the trowel, saving energy for tile setters.

3. Slip Resistance (Anti-Sagging)
  • HPMC increases thixotropy – meaning adhesive is easy to spread but stable after application.
  • Prevents tiles from sliding down vertical walls, even heavy ceramic or porcelain tiles.

4. Flexibility & Crack Resistance
  • Improves stress distribution between tile and substrate.
  • Helps absorb slight movements (thermal expansion, vibrations), reducing cracks.

5. Consistency & Durability
  • Ensures uniform mix quality, even when produced in large batches.
  • Enhances long-term adhesion strength and resistance to moisture or temperature changes.

Typical Use in Tile Adhesives
  • HPMC dosage: 0.2%–0.6% (depending on grade and viscosity).
  • Viscosity grade: 40,000–75,000 cps (2% solution, Brookfield).
  • Higher viscosity → better sag resistance.
  • Lower viscosity → better workability and dispersion.

In short: HPMC cellulose ether makes tile adhesive easy to apply, longer lasting, stronger in adhesion, and resistant to sagging. Without HPMC, cement-based adhesives would be brittle, dry too fast, and fail to hold tiles securely.


  1. Tile Adhesives:
    • High-viscosity HPMC cellulose is used to improve the open time, workability, and adhesion strength of tile adhesives. It helps prevent tiles from slipping and ensures a strong bond with the substrate.
  2. Plasters and Renders:
    • In cement and gypsum-based plasters, high-viscosity HPMC enhances workability and water retention, preventing premature drying and cracking. It also helps in achieving a smooth surface finish.
  3. Self-Leveling Compounds:
    • It is used in self-leveling compounds to control the flow properties, ensuring a smooth, level surface without segregation.
  4. Masonry Mortars:
    • High-viscosity HPMC improves the cohesiveness and water retention of masonry mortars, enhancing their strength and workability.
  5. External Thermal Insulation Systems (ETICS):
    • It is used in adhesive and base coat formulations for ETICS, providing strong adhesion and improved workability.

https://www.celluloseetherhpmc.com