HPMC (hydroxypropyl methylcellulose) is an important building additive, widely used in putty powder to enhance construction performance and improve the quality of finished products.
1. Appearance and basic physical properties
Color and form
High-quality KimaCell®HPMC is generally white or slightly yellow powder with uniform color and should not have obvious impurities or lumps. Low-quality HPMC may be off-white, contain obvious impurities or uneven particles.
Smell
Pure HPMC has no obvious odor or a slight alcohol odor. If it has a pungent or musty smell, there may be impurities or moisture deterioration.
Solubility and transparency
HPMC has good water solubility. After adding it to water and stirring, it should be able to dissolve evenly to form a transparent or translucent viscous liquid. If a large amount of precipitation or difficulty in dissolving occurs, it may be a product of poor quality.
2. Viscosity and thickening performance
Viscosity stability
Viscosity is a key indicator of HPMC, which directly affects the construction performance of putty powder. High-quality HPMC has stable viscosity at different temperatures and is not easily affected by thermal changes. Poor quality HPMC has large viscosity fluctuations when the temperature changes, which affects the construction effect.
Thickening ability
HPMC mainly improves the construction property of putty powder by thickening. High-quality HPMC has good thickening effect, which can effectively enhance the thixotropy and spreadability of putty powder, make the construction smoother, and avoid sagging.
3. Water holding capacity and construction performance
Water holding capacity
The water holding capacity of HPMC determines the open time and drying speed of putty powder. High-quality HPMC can still maintain strong water retention in high temperature environment, prevent water loss too fast, and avoid cracking or powdering caused by too fast drying of putty powder. Poor quality KimaCell®HPMC may have insufficient water holding capacity, resulting in easy cracking or powdering after putty construction.
Construction smoothness
High-quality HPMC can effectively improve the construction smoothness of putty powder, making putty easier to apply, delicate, non-sticky, and non-drawing, while inferior HPMC may cause putty powder to be astringent, drawing or poor adhesion during construction.
4. Adhesion and anti-slip properties
Adhesion properties
High-quality HPMC can significantly improve the adhesion of putty powder, making it more tightly bonded to the substrate and avoiding peeling. However, inferior HPMC may cause insufficient adhesion of putty and easy peeling and falling off.
Anti-slip properties
During facade construction, the anti-slip ability of HPMC is particularly important. High-quality HPMC can effectively prevent putty powder from sliding downward due to gravity and ensure construction quality, while inferior HPMC has poor anti-slip properties, which affects the uniform coating of putty.
5. Gel temperature
HPMC will gel after being heated to a certain temperature. The gel temperature of high-quality HPMC is usually between 60-75℃, with better temperature resistance, while the gel temperature of low-quality HPMC is low, and it is easy to affect the performance due to temperature changes during construction.
6. Experimental detection method
Dissolution experiment: Take an appropriate amount of HPMC and add it to water to observe the dissolution rate and transparency. High-quality HPMC should dissolve quickly and form a clear and transparent colloid.
Water retention test: Make HPMC into putty and apply it on the wall to observe its drying speed and whether cracks occur. High-quality HPMC can effectively delay water evaporation and prevent the putty from drying too quickly.
Viscosity test: Use a viscometer to measure the viscosity of the HPMC solution and check whether it meets the product label value.
Anti-slip test: Apply putty on the vertical wall and observe whether it slides down significantly.
7. Suggestions for choosing high-quality HPMC
Choose a well-known brand: Give priority to brands with good reputation and quality assurance to ensure product stability and reliability.
Check the test report: HPMC from regular manufacturers will provide quality test reports, including key indicators such as viscosity, water retention rate, purity, etc.
Sample test: Before purchasing in bulk, you can buy a small sample for testing to verify whether its workability and performance meet the requirements.
To judge the quality of KimaCell®HPMC in putty powder, you can start from multiple aspects such as appearance, solubility, viscosity, thickening ability, water holding capacity, construction smoothness, adhesion, anti-slip and gel temperature. By comparing experimental testing with actual construction, the quality of HPMC can be evaluated more accurately, ensuring the selection of appropriate products, thereby improving the overall performance and construction quality of putty powder.
Post time: Feb-11-2025