Fumed Silica M5 100g Thixotropic Thickening Powder

Fumed Silica M5 100g Thixotropic Thickening Powder Description

Fumed Silica M5 Thixotropic Powder – 100g Tub | Epoxy Resin Thickener, Anti-Sag Additive & Reinforcing Filler

HD Chemicals Fumed Silica M5 Thixotropic Powder is an extremely fine, lightweight amorphous silica powder widely used as a thickening, reinforcing and rheology-modifying additive in epoxy resins, polyester resins, adhesives, sealants, coatings and composite materials.

Its thixotropic properties help increase the viscosity of liquid formulations, making them thicker when stationary while allowing easier spreading or application during mixing and movement.

Fumed Silica M5 is particularly useful for reducing sagging, dripping and settling in compatible resin systems, making it a popular additive for composite manufacturing, fibreglass repairs, bonding applications and specialist coatings.

Supplied in a convenient 100g resealable tub, ideal for controlled dispensing, practical storage and small-scale resin or formulation projects.

Key Features & Benefits

• Fumed Silica M5 Powder – Fine amorphous silica additive for thickening and viscosity control.

• Epoxy & Polyester Resin Thickener – Helps produce thicker resin mixtures for bonding, filling and vertical applications.

• Thixotropic Properties – Helps reduce sagging and dripping while maintaining workable application characteristics.

• Anti-Settling Additive – Helps reduce sedimentation of pigments and fillers in suitable formulations.

• Reinforcing Filler – Can improve consistency and contribute to the mechanical properties of selected resin and adhesive systems.

• 100g Resealable Tub – Convenient packaging for handling, measuring and storage.

Common Uses

Epoxy Resin Thickening

Fumed Silica M5 is commonly added to compatible epoxy resin systems to increase viscosity and produce thicker mixtures suitable for bonding, filling and vertical applications.

Polyester Resin & Fibreglass Repairs

Useful for thickening compatible polyester resin formulations used in fibreglass repairs, composite manufacturing and surface applications.

Marine & Boat Repairs

Can be used in suitable marine-grade epoxy formulations to prepare thickened mixtures for bonding, filleting and selected fibreglass repair applications.

Adhesives & Sealants

Helps adjust viscosity and reduce sagging in compatible adhesive and sealant formulations.

Paints & Coatings

Used as a rheology modifier to help control flow, improve application properties and reduce pigment settling in selected coating systems.

Composite Manufacturing

Suitable for selected composite applications requiring viscosity control, improved handling and reduced resin movement.

Specialist Chemical Formulations

Used in compatible industrial formulations where thickening, suspension stability or thixotropic behaviour is required.

How to Use Fumed Silica M5

For Epoxy Resin Thickening

1. Prepare the epoxy resin and hardener according to the resin manufacturer's instructions.

2. Mix the resin and hardener thoroughly in the correct ratio.

3. Gradually add small quantities of Fumed Silica M5 while stirring.

4. Continue mixing until the powder is evenly dispersed.

5. Add further powder gradually until the required consistency is achieved.

6. Apply the thickened mixture according to the resin manufacturer's working time and curing instructions.

For Polyester Resin Applications

1. Check compatibility with the polyester resin system.

2. Gradually disperse the fumed silica into the resin using suitable mixing equipment.

3. Adjust the quantity until the required viscosity is achieved.

4. Add catalyst or hardener only according to the resin manufacturer's specified procedure.

5. Apply and cure following the manufacturer's instructions.

Suggested Mixing Guidance

The amount of Fumed Silica M5 required depends on the resin system, temperature, mixing method and desired consistency.

Desired ConsistencyGeneral GuidanceSlightly ThickenedAdd small quantities to increase viscosityNon-Sagging MixtureGradually increase the amount until the mixture holds its shapeThick PasteAdd progressively until a paste-like consistency is achievedStructural Bonding MixtureFollow the resin manufacturer's recommended filler formulation

Important: These are general guidelines rather than fixed mixing ratios. Fumed silica has a very low bulk density, so even small additions by weight can significantly increase viscosity.

Always follow the resin manufacturer's recommendations for filler compatibility, maximum loading and application suitability.

Frequently Asked Questions

What is Fumed Silica M5 used for?

It is primarily used as a thickening, reinforcing and rheology-modifying additive in compatible resins, adhesives, sealants, coatings and composite materials.

Can it be used to thicken epoxy resin?

Yes. Fumed silica is widely used to increase the viscosity of suitable epoxy resin systems and help create non-sagging mixtures.

Is it suitable for polyester resin?

Yes, in compatible polyester resin formulations. Always check the resin manufacturer's instructions before use.

What does thixotropic mean?

Thixotropic materials become less viscous when stirred or subjected to movement and become thicker again when left undisturbed. This helps reduce sagging and dripping during application.

Can I use it for fibreglass repairs?

Yes. Fumed silica is commonly used in suitable resin formulations for fibreglass repairs, bonding and composite applications.

Is it suitable for boat repairs?

It can be used as a thickening additive in compatible marine epoxy and polyester resin systems. The suitability of the finished mixture depends on the resin and repair requirements.

Does fumed silica make epoxy stronger?

Fumed silica can influence the mechanical and handling properties of certain resin systems, but it does not automatically improve every type of strength. Performance depends on the resin formulation, filler loading and application.

Can it prevent resin from dripping?

Yes. Its thixotropic properties can help reduce sagging and dripping on vertical or overhead surfaces when used at an appropriate concentration.

Can it be used as a gap filler?

It can help produce thickened resin mixtures for certain gap-filling applications. For large gaps or structural repairs, follow the resin manufacturer's recommended filler system.

Is Fumed Silica M5 the same as ordinary silica sand?

No. Fumed silica is an extremely fine, lightweight amorphous silica powder with a very high surface area. It behaves differently from ordinary silica sand and is particularly effective for viscosity modification.

Does it dissolve in resin?

No. Fumed silica disperses throughout the resin rather than dissolving. Proper mixing is important for consistent results.

Is it suitable for cosmetic or food applications?

This product is supplied for industrial and technical applications. It is not intended for food, pharmaceutical or cosmetic use unless the specific grade and relevant compliance requirements have been verified.