Surface Modifier | Hydrophobing Agents | Water Repellent

SiSiB® PSI0740

Potassium Methyl Siliconate
Synonym: Potassium siliconate

Chemical Structure


SiSiB® PSI0740 is a water-dilutable solution of potassium methyl siliconate (Potassium siliconate) developed to impart water repellency to a wide variety of natural stone and masonry surfaces. The siliconate reacts with carbon dioxide in the air to form an insoluble repellent surface and reduce water absorption within 24 hours.

It is suitable for the surface of natural stone, like sandstone, limestone, and red brick, gray brick, granite, ceramics etc.; It is not suitable for polished or glazed surfaces.

Typical Physical Properties

Chemical Name: Potassium methyl siliconate
CAS No.: 1312-76-1
EINECS No.: 215-199-1
Empirical Formula: K4SiO4
Molecular Weight: 248.44
Color and Appearance: Clear to slightly yellow liquid
Density [25°C]: 1.20~1.35
pH value: 12~13
Solid Contents: 40~50%
Active Substance: 35~40%


Reduces water absorption into the substrate, thus reducing spalling due to freeze-thaw and efflorescence, thereby increasing the life of the substrate.
Colorless and non-yellowing protection preserves the natural appearance of the substrate. Will not form a surface film or gloss.
Treated surfaces retain natural vapor permeability.
Suitable for interior and exterior surfaces.
No solvent odor.

SiSiB® PSI0740 is supplied concentration of 40 percent in water; SiSiB® WR2000 is usually diluted to a concentration of 3 percent solids or less before application. To prepare a 3 percent solution, mix one liter SiSiB® WR2000 as supplied, with 15 liters of water.

Application should be avoided on extremely windy days to avoid rapid evaporation of the water carrier.


Net weight 240Kg steel drum or 1000Kg IBC container, for more details, please visit Packing Centre.

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