AEROSIL R 202 is a fumed silica from Evonik after-treated with polydimethylsiloxane (PDMS), especially recommended for 2-pack epoxy resins and known for improving corrosion resistance alongside its rheology effect. For composite material buyers and coating formulators sourcing anti-sag, anti-settling, and thixotropic additives, it is a reference grade used across marine coatings and protective coatings.

Key Technical Properties of AEROSIL R 202
According to Evonik’s official technical data sheet, this fumed silica grade is characterized by the following properties, which buyers should confirm against their own incoming-goods testing:
| Specific surface area (BET) | 80 – 120 m²/g |
| pH value | 4.0 – 6.0 |
| Carbon content | 3.5 – 5.0% |
| Loss on drying | <0.5% |
| SiO2 content | >99.8% |
| Tamped density | Approx. 60 g/l |
| Recommended addition level | 1.0 – 2.0% of total formulation, as supplied |
| Shelf life | 24 months from date of manufacture |
Why Buyers Choose This Fumed Silica for Epoxy and Protective Coating Systems
Evonik lists the key benefits of this product as excellent rheology effect, suitability especially for 2-pack epoxy resins, and improved corrosion resistance. In coating systems specifically, it is documented to deliver:
- Anti-settling performance that keeps pigments and fillers suspended during storage
- Anti-sagging control that helps formulations hold film thickness on vertical surfaces
- Improved corrosion resistance in protective coating formulations
- Reliable rheology behavior in polar liquid systems such as epoxy, polyurethane, or vinylester resins
Suitability Across Coating Systems
Per Evonik’s technical data sheet, AEROSIL R 202 is positioned across waterborne, solventborne, radiation-curing, one-pack, and two-pack coating systems, with suitability levels that vary by system. Addition to the coating is possible as supplied or as a predilution, and Evonik notes that compatibility of the PDMS-treated product should be tested in the specific coating before scale-up.
Typical Applications for AEROSIL R 202
Evonik’s product documentation names marine coatings and protective coatings as typical applications, and the product is especially recommended for 2-pack epoxy resin systems. These applications are relevant to auxiliary agents used in composite and coating manufacturing:
- Marine coatings and protective coatings
- 2-pack epoxy resin systems
- Polyurethane and vinylester resin-based coating systems
- Anti-settling and anti-sagging formulations requiring reliable rheology control
Sourcing This Fumed Silica Grade to Avoid Common Coating Mistakes
As a recommended international brand product, AEROSIL R 202 is available through supply chain resource support for overseas buyers who need consistent fumed silica performance across production lots. Because the product’s rheological behavior depends on dispersion quality, addition level, and compatibility testing with the PDMS treatment, buyers sourcing this grade for marine, protective, or epoxy coating formulations should request a current certificate of analysis for each shipment and verify BET surface area, carbon content, and loss-on-drying figures against Evonik’s official product documentation before full-scale use.
FAQ
What is the BET surface area of AEROSIL R 202?
Evonik’s technical data sheet lists the specific surface area (BET) of AEROSIL R 202 at 80 – 120 m²/g, lower than many other AEROSIL grades.
Is AEROSIL R 202 suitable for 2-pack epoxy resin systems?
Yes, Evonik specifically highlights that this grade is especially recommended for 2-pack epoxy resins, among its key benefits.
What is the recommended addition level for AEROSIL R 202?
Evonik recommends an addition level of 1.0 – 2.0% of total formulation, as supplied, with addition possible directly or as a predilution.
How should AEROSIL R 202 be stored?
AEROSIL R 202 should be stored in its original unopened packaging under dry conditions, away from volatile substances, and has a shelf life of 24 months from the date of manufacture.
How can I request a quote or sample?
Contact our team with your target application and required volume, and we will provide sourcing and supply chain resource support based on current availability.
Looking to source AEROSIL R 202 for your next marine, protective, or epoxy coating formulation? Contact our team today with your application details and volume requirements, and we will help connect you with the right supply chain resources.