Fumed Silica - Hydrophilic and Hydrophobic

For over 70 years Evonik’s™ AEROSIL® has been a market leading brand of fumed silica. With a unique range of both hydrophilic and hydrophobic grades available the number of applications are endless. Fumed (pyrogenic) silica is composed of synthetic silicon dioxide (SiO2) which is entirely amorphous, eliminating the risks posed by crystalline silica.

One of the main applications for fumed silica is increasing the viscosity, pseudoplasticity and thixotropy of a wide range of liquid systems. However there are many more applications besides this common use case. Evonik’s™ AEROSIL® range is the most extensive range of fumed silica on the market, with many of their products tailored for particular applications. The versatility of AEROSIL® means that it can be found all around us, from the paints on our walls to the fertilizers on our crops. Read on to find out more about this exciting product range.


    • Chemically inert synthetic amorphous silica. High purity

    • Available in hydrophilic and surface-treated hydrophobic grades

    • A wide range of surface areas available

    • Broad legislative approvals on many grades e.g. indirect food contact

    • Mixed fumed silica/metal oxide grades available


    • Efficient rheology control in a wide range of simple and complex liquid systems. Imparts viscosity, pseudoplasticity and thixotropy. Stabilises pigments and prevents sagging.

    • Provides effective free flow and anti-caking behaviour. Can be used as a solid carrier for liquids.

    • Improves mechanical and optical properties of silicone rubber.

    • Improves anti-corrosion performance of protective and marine coatings. Reduces moistures sensitivity and increases hydrophobicity. Useful in silicone sealants for extending shelf life for example.

    • Anti-blocking agent for PET films.

    • Many more applications: greases, batteries, agrochemicals etc.

Typical Applications

    • Rheology and thixotropy control in coatings, inks, sealants & adhesives

    • Improving anti-corrosion properties of protective coatings

    • Scratch resistance in coatings

    • Thickening and hydrophobicity of greases

    • Electrolyte immobilization in lead-acid batteries

    • Anti-settling agent in pigment dispersions and suspension concentrates

    • Solid carrier for liquids

    • Mechanical and optical enhancement of silicone rubbers

    • Impart free-flow and anti-caking properties in powders

    • Metal and glass polishing

Featured grades with technical datasheets

A brief overview of the key grades is given below. You will find the Technical Datasheets (TDS) available for download. If you are looking for a Safety Datasheet (SDS) or Product Safety Information (PSI) then please get in touch by phone or via the contact buttons at the top of the page.

Should you not find what you are looking for here then please note that we have further grades available besides these. One of our Technical Sales team will be happy to help. All of the sales team are technically qualified and will be able to advise you on which product to choose. You can either call us, email us or fill in a quick form at the top of the page to get us to call you (Request a Callback). A sample can be requested via the button at the top of the page as well. Please note that by providing us with your contact details, you are agreeing for us to potentially contact you.

Related brochures & technical literature

You will find some of the key product brochures available for download below. There are more brochures available upon request. If you would like to discuss your enquiry further then please get in contact by phone or by filling in the "Request a Callback" form at the top of the page. Someone from the technical sales team will then call you within 24 hours, to discuss your project further.

AEROSIL® - Fumed Silica Technical Overview

A complete overview of the Evonik™ AEROSIL® range. Something of a reference manual it goes through the manufacturing process, properties of the grades, application related effects and more. If you are interested in learning about the range in detail then this is a very useful document.

AEROSIL® - Fumed Silica Technical Overview Brochure /




Successful Use of AEROSIL® Fumed Silica in Liquid Systems

This brochure goes into great detail as to how the formulator should use AEROSIL® fumed silica in order to get the most out of it. Dispersion considerations are key with this type of material! Read on for more information.

Successful Use of AEROSIL® Fumed Silica in Liquid Systems Brochure /




Physico-chemical data of AEROSIL® Fumed Silica

A useful cheat sheet giving an overview of the main physico-chemical properties of the different grades of AEROSIL®. Please note that there are more grades than these available however these form the core of the range.

Physico-chemical data of AEROSIL® Fumed Silica Brochure /