SEMISIL 200

Yes. SemiSIL 200 is a 1:1 technical equivalent to leading hydrophilic fumed silica 200 grades. It shares the identical CAS Number (112945-52-5), a 200 m²/g BET surface area, and ≥ 99.8% SiO2 purity. Formulators can confidently transition to SemiSIL 200 to reduce costs without altering existing milling or dispersion protocols.

For general liquid systems such as Unsaturated Polyester Resin (UPR), coatings, and standard adhesives, the typical dosage ranges from 0.5% to 2.0% by weight. For silicone rubber reinforcement, loadings can range from 10% to 30%. We recommend starting at the lower end and scaling up based on your required thixotropic index.

Because fumed silica builds viscosity by forming a 3D hydrogen-bonded network, high-shear dispersion is critical. We recommend using a high-speed dissolver (e.g., Cowles blade), rotor-stator system, or a three-roll mill. Simple low-shear stirring will leave agglomerates intact, resulting in poor anti-sagging performance and surface defects.

In highly polar systems (like certain epoxies or polyurethanes), hydrophilic fumed silica can experience a slight viscosity drop over time, known as the "aging effect." If long-term shelf stability in polar adhesives is your primary goal, we highly recommend switching to our silicone oil-treated hydrophobic grade, SemiSIL R202.

As a highly hydrophilic material, SemiSIL 200 readily absorbs moisture from the air, which can physically hinder its ability to form hydrogen bonds and reduce thickening efficiency. It must be stored in its original, tightly sealed multi-layer kraft paper bags in a dry, well-ventilated warehouse. Under proper conditions, its shelf life is 24 months from the date of manufacture.