Caulking Compound

As an additive, Fumed silica can play a thickening and thixotropic effect in the Caulking Compound, solve the problems of flowing, dripping, and collapsing in the caulking compound construction, and can reinforce the beautifying agent to increase the tensile strength and Bond strength.

what is Caulking Compound?

A caulking agent, also known as a caulking compound or simply caulk, is a material used to seal gaps and joints in various structures, such as buildings, vessels, or pipelines. It is typically a flexible, waterproof substance that fills and seals gaps to prevent air, water, dust, or other unwanted substances from entering or escaping through the joints.

Caulking agents are commonly applied in construction and home improvement projects to provide airtight and watertight seals around windows, doors, gaps between walls and floors, plumbing fixtures, and other areas where there is a need for weatherproofing or insulation. They come in different forms, including cartridges for use with caulking guns, squeezable tubes, or pre-formed strips.

The main purpose of a caulking agent is to create a durable and flexible seal that can withstand environmental factors such as temperature changes, moisture, and movement of the sealed surfaces. It helps to improve energy efficiency, prevent leaks, reduce noise transmission, and enhance the overall appearance and longevity of the structure.

Caulking agents are available in various types and formulations, including silicone, polyurethane, acrylic, and latex-based caulks. Each type has its own properties and suitability for specific applications, such as indoor or outdoor use, high-temperature environments, or areas with high levels of moisture.

Caulking compounds are prone to sedimentation during storage, which can impact their performance. When used on vertical or overhead surfaces, such as walls or ceilings, they have a tendency to flow and drip. Therefore, it is necessary for caulking compounds to have a certain level of flowability while maintaining their desired form and improving physical strength. They are primarily used in applications such as epoxy-colored sand, epoxy tile grout, and polyurethane-based tile grouts.

HIFULL® Fumed Silica(additive) in caulking compounds

Thickening and thixotropic behavior: HIFULL® fumed silica improves the rheological control of caulking compounds, maintaining a desired consistency during curing and enhancing the efficiency of caulking application. Read more

Sag resistance: It prevents caulking compounds from flowing, dripping, or collapsing when applied on vertical or overhead surfaces.

Reinforcement: HIFULL® fumed silica enhances the tensile strength and bonding properties of caulking compounds, increasing durability and extending their lifespan.

Waterproofing: Hydrophobic fumed silica enhances the water-repellent properties of caulking compounds, improving their waterproofing and mold resistance capabilities.

The application effects of fumed silica in caulking compounds

Epoxy grout: It improves the rheological properties of epoxy grout, facilitating easy application and enhancing production efficiency. It strengthens the durability and toughness of epoxy grout and enhances its waterproofing and moisture resistance capabilities.

Polyurethane-based tile grout: It increases the viscosity and thickness of polyurethane-based tile grout, preventing dripping and sagging during application, increasing bonding strength, and improving the waterproofing and mold resistance properties. It extends the lifespan of the grout without altering its original color.

Water-based colored sand grout: It is a green material that is non-toxic and environmentally friendly. It improves the hardness and toughness of water-based colored sand grout after curing, enhances workability and practicality during application, and enhances bonding strength, wear resistance, and resistance to bending and compression.

Epoxy-colored sand grout: It enhances the structural stability of epoxy-colored sand grout, increases its physical and bonding strength, improves the ease of mixing, application, and cleaning, and provides significant resistance to oil and stains.

Recommended products and dosages

Application FieldFunctions and EffectsRecommended DosageRecommended HydrophilicRecommended Hydrophobic
Epoxy groutReinforcement/rheological control/sag resistance/waterproofing and stain resistance3-6%HL-200HL-260HB-139
Polyurethane-based tile groutThickening and thixotropic behavior/bonding strength improvement/sag resistance3-6%HL-200HL-260HB-139
Water-based colored sand groutSag resistance/enhanced toughness/resistance to bending and compression6%HL-200HL-260HB-139
Epoxy-colored sand groutIncreased viscosity/thickening/physical strength enhancement/stability3-6%HL-200HL-260HB-139

Please note that the recommended dosages may vary depending on specific formulations and desired performance characteristics. It is recommended to conduct small-scale tests to determine the optimal dosage for each application.

Related Project

Project details

  • Application: Two-component Polyurea Sealants/Tile Grout
  • Product Name: HB-139
  • Location: Shandong Province, China
  • Problem: to cut down costs while keep good quality

Company A is using an international brand of hydrophobic fumed silica with PDMS/polydimethylsiloxane-treated, and they would like to cut down the cost and keep the original product quality by finding an alternative hydrophobic fumed silica. Learn More>>


Our main products are fumed silica SiO2, fumed titanium dioxide TiO2, and fumed alumina Al2O3. We get 20+ years of expertise and 20,000 tons of annual capacity. We supply total of 23 grades of hydrophilic & hydrophobic fumed silica. We get registration of REACH and pre-registration of K-REACH & KKDIK. We are the leading setting body of ISO18473-1:2015ISO18473-3:2018, and ISO 23157:2021. Learn More About Hifull

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Hello, Customers

My name is Van, I’m the business manager of HIFULL, I have been in Fumed Silica Industry for more than 10 years. Feel free to contact me. I’m happy to provide you the best service and products.
Business Manager