In the formulation design of dry mix and ready-mixed mortars, Hydroxypropyl Methyl Cellulose (HPMC) is a common non-ionic cellulose ether widely used to improve the workability and physical properties of mortar. Construction Grade HPMC is a product specifically developed for building applications, offering stable performance in water retention, thickening, and application smoothness.
Product Basic Characteristics
Construction Grade HPMC is made from natural plant fibers through chemical processing. It appears as a white or off-white powder and is soluble in cold water, forming a transparent or translucent colloidal solution. Its typical properties include:
Good Water Solubility: Disperses and dissolves quickly in cold water without forming lumps.
Stable Water Retention Capacity: Helps reduce rapid water evaporation, providing sufficient time for cement or gypsum hydration.
Moderate Thickening Effect: Adjusts mortar viscosity and improves sag resistance.
Non-Ionic Structure: Offers good adaptability to acidic and alkaline environments, with high compatibility with cement, gypsum, lime, and other cementitious materials.
Improved Workability: Makes mortar smoother and less sticky to trowels, facilitating manual or machine application.
Main Application Areas
Construction Grade HPMC is suitable for various dry mix mortar systems. Common applications include:
Cement-based Plastering Mortar: Enhances bond strength with the substrate and reduces cracking risks.
Masonry Mortar: Improves spreading length and construction efficiency, ensuring dense mortar joints.
Tile Adhesives: Extends open time, allowing easier adjustment of tile positions.
External Thermal Insulation Composite Systems (ETICS) Basecoat and Adhesive Mortars: Enhances water retention and construction convenience.
Gypsum-based Mortars (Lightweight Plaster, Joint Filler, etc.): Assists in paste stability and workability.
Self-Leveling Mortars: Aids in balancing suspension and flow properties.
Technical Data Reference (Typical Values)
| Parameter | Typical Range | Description |
|---|---|---|
| Appearance | White or off-white powder | —— |
| Methoxy Content (%) | 19.0 – 24.0 | Affects gel temperature and water retention |
| Hydroxypropoxy Content (%) | 4.0 – 12.0 | Affects hydrophilicity and dissolution rate |
| Loss on Drying (%) | ≤ 5.0 | Facilitates weighing and storage stability |
| Viscosity Range (mPa·s, 2% solution, 20°C) | 400 – 200,000 (various grades available) | Select grade based on mortar type |
Note: The above data represent typical product performance ranges. Different grades may vary. Please refer to the specific product test report for accurate values.
Usage Recommendations
Addition Rate: Typically 0.02% – 0.50% of the total cementitious material weight, adjusted based on mortar type and desired performance.
Mixing Method: Premix with other powder materials uniformly before adding to the mixing equipment to avoid direct dissolution in water and lump formation.
Environmental Adaptation: When temperatures are high or the substrate is highly absorbent, consider adjusting the HPMC dosage or using it in combination with other admixtures.
Packaging and Storage
Packaged in paper-plastic composite bags with an inner moisture-proof film. Net weight 25kg per bag.
Store in a cool, dry, and well-ventilated environment away from direct sunlight and moisture.
