DOWSIL 520
Harmonization Code : 8001.20 | Unwrought tin: Tin alloys
Main features
- Water-Dilutable 40% Active Emulsion
- Deep Mineral-Substrate Penetration
- Substrate-Specific Water Repellency
Product Description
DOWSIL 520 Dilutable Water Repellent Emulsion supplies a milky-white, water-dilutable silane/siloxane emulsion containing 40% active material for formulating penetrating water-repellent treatments. It can be used as supplied or diluted with water for mineral substrates such as brick, stone, concrete and mortar. After application, the active molecules penetrate absorbent surfaces and react to form a hydrophobic treatment that inhibits water absorption while retaining the substrate's original appearance. Laboratory water-exclusion results vary with substrate and active-solids concentration, so dilution should be selected using test applications on the specific surface.
Key features
- 40% active emulsion: Can be used as supplied or diluted with water for treatment formulation.
- Penetrating mineral treatment: Small active molecules support penetration into absorbent masonry surfaces.
- Condition-specific water exclusion: Performance is separated by substrate and active-solids level.
Applications
Penetrating water-repellent treatments for brick, stone, concrete and mortar.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Thermal Properties
Additional Information
As-supplied / before-processing properties
Typical as-supplied emulsion properties. Values are not specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Color | Milky white | As supplied | |
| Nonvolatile content | 40 | % | Typical active content |
| pH | 4.5 | Typical value | |
| Specific gravity | 0.985 | At 25 deg C | |
| Flash point | >100 | deg C | Closed cup |
| Density | 8.216 | lb/gal | Typical value |
| VOC content | <300 | g/L | Typical value |
| Solvent / thinner | Water | As supplied |
After-processing / final-state properties
Laboratory water-repellency results for treated mineral substrates. Performance varies with substrate and active-solids concentration.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Water exclusion, mortar cubes | 92 / 94.8 / 93.9 | % | After 24 hr immersion; 5% / 10% / 20% active solids; ASTM C642 |
| Water exclusion, cement brick | 63.9 / 77 / 82.5 | % | After 24 hr immersion; 5% / 10% / 20% active solids; modified ASTM C67 |
| Water exclusion, Belden brick | 80.3 / 69.8 / 41.1 | % | After 24 hr immersion; 5% / 10% / 20% active solids; modified ASTM C67 |
| Water exclusion, Glen Gary brick | 77.7 / 48.3 / 43.3 | % | After 24 hr immersion; 5% / 10% / 20% active solids; modified ASTM C67 |
| Water exclusion, mortar cubes | 74.0 | % | After 21 days immersion; 40% active solids; modified NCHRP 244 |
| Penetration, mortar cubes | 4-5 | mm | 40% active solids; modified NCHRP 244 |
| Leak-rate reduction, concrete block | 76 | % | 5% active solids; modified ASTM E514 |
| Penetration, concrete block | 15 | mm | 5% active solids; modified ASTM E514 |
