SILIFLO FS-200 Hydrophilic Fumed Silica

SILIFLO FS-200 Hydrophilic Fumed Silica

SILIFLO FS-200 is a high-purity, hydrophilic amorphous fumed silica designed as a high-performance rheology modifier, thickener and anti-sag additive for epoxy, polyester, vinyl ester, polyurethane, silicone and other resin systems.

With a specific surface area of approximately 200 m²/g, SILIFLO FS-200 provides a very strong thickening effect at relatively low addition levels. It can transform a low-viscosity resin into a controlled-flow, non-sag or paste-like consistency while adding very little weight to the formulation.

Unlike conventional mineral fillers that are generally used at much higher loadings to add bulk, SILIFLO FS-200 is primarily used to control rheology. It helps prevent resin from running or sagging on vertical surfaces, improves suspension of pigments and heavier fillers, and allows the formulator to precisely adjust the consistency of a resin system.

Key Features

• 200 grade hydrophilic fumed silica
• High specific surface area – 200 ± 25 m²/g
• High purity – SiO₂ ≥99.8%
• Powerful thickening and rheology control
• Excellent anti-sag performance
• Improves thixotropic behaviour
• Helps suspend pigments and mineral fillers
• Reduces settling and sedimentation
• Improves control on vertical and overhead applications
• Can produce non-sag adhesives, fillers and repair pastes
• Very low addition levels compared with conventional mineral fillers
• Suitable for a wide range of resin and polymer systems

Typical Applications

SILIFLO FS-200 is suitable for thickening and controlling the flow of epoxy resins, polyester resins, vinyl ester resins, polyurethane systems and silicone systems.

Typical applications include structural adhesives, gap-filling compounds, marine repair systems, filleting compounds, fairing formulations, concrete repair compounds, vertical and overhead repairs, potting compounds, sealants, coatings and filled resin systems.

It is particularly useful where a resin needs to remain in position rather than flowing away from the application area.

Typical Characteristics

Mixing with Resin

SILIFLO FS-200 should be added gradually to the resin while mixing until the desired consistency is achieved. Because fumed silica has an extremely low bulk density and high surface area, relatively small additions can produce a substantial increase in viscosity.

Lower addition levels can improve flow control and reduce settling. Increasing the concentration produces progressively greater thixotropy and anti-sag performance, eventually creating a heavy non-sag compound or paste.

For best dispersion, use suitable mechanical mixing equipment and add the powder slowly. Avoid dumping large quantities into the resin at once, as the extremely fine powder can be difficult to wet out and may generate airborne dust.

Use with Other Fillers

SILIFLO FS-200 can be used by itself or in combination with mineral fillers such as CALCOFILL HP80 calcium carbonate.

This combination is particularly useful in epoxy formulations. CALCOFILL HP80 can provide bulk, body and mineral solids, while SILIFLO FS-200 can be used at a much lower concentration to fine-tune thixotropy, improve suspension and provide anti-sag performance.

This allows formulators to produce anything from a slightly thickened resin through to heavy-bodied adhesives, repair compounds and non-sag pastes.

Available Sizes

SILIFLO FS-200 is packed by volume due to the exceptionally low bulk density of fumed silica.

Store in a cool, dry place with the container securely closed. Protect from moisture and contamination.

Note: Fumed silica is an extremely fine, lightweight powder. Use appropriate dust-control measures and personal protective equipment when handling and mixing.