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AEROSIL® R 805

AEROSIL® R 805 is a high thickening fumed silica surface treated with OCTMO.

Brand: AEROSIL (33 products)

INCI Name: Silica Caprylyl Silylate

Chemical Name: Silica gel, pptd., cryst.-free

Functions: Rheology Modifier, Thickener, Viscosity Modifier

CAS Number: 112926-00-8

Chemical Family: Silica

Enhanced TDS

Enhanced TDS

Knowde-enriched technical product data sheet

Identification & Functionality

Features & Benefits

Benefit Claims
Labeling Claims
CASE Ingredients Features
Fluids & Lubricants Features
Materials Features
Product Features
  • Homogeneously hydrophobic surface
  • Effective in the rheological control of complex liquid systems (such as adhesive and sealant materials)
  • Efficient effect as flow agent
  • Fine particle size

Applications & Uses

Markets
Applications
Compatible Polymers & Resins
AEROSIL® Fumed Silica in Lubricating Greases

AEROSIL® fumed silica helps to build a stable matrix to increase viscosity and suppress oil separation in lubricating greases. It can be used in the following systems:

  • In non-soap greases, used in high-temperature applications up to 230° C as well as for extreme-pressure and multipurpose greases.
  • In soap greases, thickened by fatty acid soaps of lithium, calcium, sodium or aluminum, AEROSIL® fumed silica can be used to further improve the performance of the lubricating grease.
  • Hydrophilic fumed silica provides optimized thickening effects in non-polar oils.
  • Hydrophobic fumed silica provides viscosity control and increased water repellency in semi-polar to polar oils.
  • The surface area of the silica and the volume fraction of the silica in the fi nal mass play a role in the long term storage and heat stability.
Lubricating Grease Applications

The use of AEROSIL® fumed silica is recommended for lubricating greases used in industrial applications, automotive, electrical as well as food grade.

  • Electrical - Offers rheology control as well as water resistance.
  • Industrial - Offers rheology control as well as excellent oxidation resistance against water and chemicals.
  • Automotive - Offers rheology control as well as excellent oxidation resistance against water and chemicals.
  • Food - Hydrophilic AEROSIL® are generally recognized as safe (GRAS; direct food contact). Offers rheology control as well as water resistance
Premium Product Recommendations

Provides excellent performance in oil separation and cone penetration due to high hydrophobicity as well as giving outstanding stability.

Properties

Physical Form
Appearance
Fluffy white powder
Physico-Chemical Properties
ValueUnitsTest Method / Conditions
Unit Weight (Netto)10kg-
HCI Content⁸,¹¹max. 0.025wt %-
TiO₂ Content⁸max. 0.030wt %-
Fe₂O₃ Content⁸max. 0.010wt %-
Al₂O₃ Content⁸max. 0.050wt %-
SiO₂ Content⁸min. 99.8wt %-
Carbon Content4.5 - 6.5wt %-
pH Value⁵ (4%, Aqueous dispersion)3.5 - 5.5 10wt %-
Loss on Ignition⁴,⁷ (2h at 1000°C)5.0 - 7.0wt %-
Loss on Drying³ (2h at 105°C, when leaving the plant)max. 0.5wt %-
Tamped Density²60g/l-
BET Surface Area (BET¹)125 - 175m²/g-
Behavior Towards WaterHydrophilic--
Note

1 - According to DIN 9277
² - According to DIN EN ISO 787/11, JIS K 5101/20 (not sieved)
3 - According to DIN EN ISO 787/2, ASTM D 280, JIS K 5101/23
4 - According to DIN EN ISO 3262-20, ASTM D 1208, JIS K 5101/24
5 - According to DIN EN ISO 787/9, ASTM D 1208, JIS K 5101/26
6 - According to DIN EN ISO 787/18, JIS K 5101/22
7 - Based on dried substance (2 hours at 105 °C)
8 - Based on ignited substance (2 hours at 1000 °C)
9 - Special moisture-protective packaging
10 - in water: methanol = 1:1
11 - HCI-content is a part of ignition loss
12 - Packaging of densed material: 20 kg

Regulatory & Compliance

Technical Details & Test Data

Test Methods
  • AEROSIL® fumed silica is a highly dispersed, amorphous, very pure silica manufactured by high-temperature hydrolysis of silicon tetrachloride in an oxyhydrogen gas flame. The primary particles formed in the AEROSIL® process are virtually spherical and free of pores.
  • During the formation of the primary particles, aggregates are formed which further accumulate into agglomerates. Under shear, these agglomerates can be returned back into smaller aggregates.
  • Siloxane and silanol groups are found on the surface of the AEROSIL® particles. This latter type of functional group in particular is responsible for the hydrophilic behavior of untreated AEROSIL®. Figure shows the surface groups of hydrophilic AEROSIL® grades.

AEROSIL® R 805 - Aerosil® Fumed Silica

Surface groups of hydrophilic AEROSIL® grades.

Figure below provides a summary of these and highlights the difference between them and hydrophilic AEROSIL® grades according to the schematically represented surface groups. All hydrophobic AEROSIL® grades bear the suffix "R" to indicate their water- repellent character.

AEROSIL® R 805 - Aerosil® Fumed Silica - 1

Surface groups of hydrophobic AEROSIL® grades.

The hydrophobic nature of aftertreated AEROSIL® grades compared with AEROSIL® 300 can be illustrated by means of moisture adsorption in increasingly humid conditions. Figure below shows the corresponding isotherms.

AEROSIL® R 805 - Aerosil® Fumed Silica - 2

Adsorption isotherms of various AEROSIL® grades at room temperature (small samples).

AEROSIL® Fumed Silica
  • AEROSIL® fumed silica is a highly dispersed, amorphous, very pure silica manufactured by high-temperature hydrolysis of silicon tetrachloride in an oxyhydrogen gas flame. The primary particles formed in the AEROSIL® process are virtually spherical and free of pores.
  • During the formation of the primary particles, aggregates are formed which further accumulate into agglomerates. Under shear, these agglomerates can be returned back into smaller aggregates.
  • Siloxane and silanol groups are found on the surface of the AEROSIL® particles. This latter type of functional group in particular is responsible for the hydrophilic behaviour of untreated AEROSIL®. Figure shows the surface groups of hydrophilic AEROSIL® grades.

AEROSIL® R 805 - Aerosil® Fumed Silica

Surface groups of hydrophilic AEROSIL® grades.

Figure below provides a summary of these and highlights the difference between them and hydrophilic AEROSIL® grades according to the schematically represented surface groups. All hydrophobic AEROSIL® grades bear the suffix "R" to indicate their water- repellent character.

AEROSIL® R 805 - Aerosil® Fumed Silica - 1

Surface groups of hydrophobic AEROSIL® grades.

The hydrophobic nature of aftertreated AEROSIL® grades compared with AEROSIL® 300 can be illustrated by means of moisture adsorption in increasingly humid conditions. Figure below shows the corresponding isotherms.

AEROSIL® R 805 - Aerosil® Fumed Silica - 2

Adsorption isotherms of various AEROSIL® grades at room temperature (small samples).

Packaging & Availability

Country Availability
Packaging Type
Regional Availability
  • North America
Packaging Information

AEROSIL® R 805 is supplied in multiple layer 10 kg bags.

Storage & Handling

Shelf Life
2 years
Storage Conditions

Recommend to store the product in closed containers under dry conditions and to protect the material from volatile substances. AEROSIL® R 805 should be used within 2 years after production.