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ELASTOSIL® RT 773

1 of 36 products in this brand
ELASTOSIL® RT 773 is a non-slump, condensation-curing RTV-2 silicone. When used with a curing agent from the WACKER® Catalyst T 77 series, it forms a self-bonding and durable silicone rubber. Cured ELASTOSIL® RT 773 offers excellent long-term stability against weathering, moisture, and UV light. The compressible silicone elastomer can continuously endure changing climatic conditions, UV radiation, and temperatures as high as 140°C (284°F) without damage.

Product Type: 2K (2 component) Sealant

Application Area: Cure In Place Gasket, Form In Plastic Gaskets (FIPG), Gaskets, Printed Circuit Boards, White Goods

Cure Method: Air Dry, Moisture Cure

Chemical Family: Silicones

Technical Data Sheet

Knowde Enhanced TDS

Identification & Functionality

Chemical Family

Features & Benefits

Special Features
  • Compressible
  • Condensation-curing
  • Electrically insulating
  • Low density
  • Media resistant
  • Non-slump
  • Self-adhesive
  • Shear thinning
  • Thixotropic
  • Two-component
  • UV & weathering-resistant

Applications & Uses

Applications
  • Cured-In-Place-Gaskets (Dry Type)
  • White Goods
Application Details
  • Compressible general purpose grade for CIPG applications
  • Typical fields of application: household appliances, automotive, mechanical engineering.

Processing

Mixing and curing:

  • ELASTOSIL® RT 773 is processed in combination with a curing agent, such as WACKER® Catalyst T 77 or WACKER® Catalyst T 77 PLUS. Prior to application the two compounds should be thoroughly mixed, either manually or by automatic metering lines equipped with static or dynamic mixing devices.
  • The recommended mixing ratio is 10:1 by weight. Potlife and curing speed can be modified within limits by adjusting the ratio of base compound (ELASTOSIL® RT 773) to curing agent (WACKER® Catalyst T 77 or WACKER® Catalyst T 77 PLUS).
  • Varying the mixing ratio between 8:1 and 12:1 usually has a small effect on the properties of the cured rubber. However, if the mixing ratio differs substantially from the recommended scope, preliminary tests should be carried out to check the cured material’s suitability.
  • General information about pot life and resulting curing times are given in the respective tables "Catalyzed". Moreover curing speed can be slightly accelerated by raising the temperature. Heating, however, must not exceed 60 °C before curing is completed.
  • After completion of the vulcanization process the product may continuously be exposed to constantly changing climatic conditions, UV radiation and high temperature without damage. Cured ELASTOSIL® RT 773 usually shows good primerless adhesion to many substrates, e.g. glass, ceramics, metals, plastics and powder coatings.

Removal:

If removal of the silicone from machines or dispensing equipment is necessary, white spirit or similar nonpolar solvents are recommended. However, cleaning ideally should take place before the silicone is fully vulcanized. Cured silicone needs to be removed mechanically, if necessary in combination with a swelling agent (solvent).

Properties

Physical Form
Typical Properties
ValueUnitsTest Method / Conditions
Recommended Service Temperature-50 to +140°C
Catalyst Properties
ValueUnitsTest Method / Conditions
Pot Life (10:1, Mixed with WACKER Catalyst T 77, at 23°C)15 - 20 minutesDIN EN ISO 3219
Pot Life (10:1, Mixed with WACKER Catalyst T 77 PLUS, at 23°C)6 - 10 minutesDIN EN ISO 3219
Pot Life (12:1, Mixed with WACKER Catalyst T 77 PLUS, at 23°C)10 - 15 minutesDIN EN ISO 3219
Pot Life (12:1, Mixed with WACKER Catalyst T 77, at 23°C)20 - 35 minutesDIN EN ISO 3219
Pot Life (8:1, Mixed with WACKER Catalyst T 77 PLUS, at 23°C)4 - 6 minutesDIN EN ISO 3219
Pot Life (8:1, Mixed with WACKER Catalyst T 77, at 23°C)7 - 12 minutesDIN EN ISO 3219
Tack-Free Time (10:1, Mixed with WACKER Catalyst T 77, at 23°C)approx. 120 minutes
Tack-Free Time (10:1, Mixed with WACKER Catalyst T 77 PLUS, at 23°C)approx. 50 minutes
Tack-Free Time (12:1, Mixed with WACKER Catalyst T 77, at 23°C)approx. 180 minutes
Tack-Free Time (12:1, Mixed with WACKER Catalyst T 77 PLUS, at 23°C)approx. 90 minutes
Tack-Free Time (8:1, Mixed with WACKER Catalyst T 77 PLUS, at 23°C)approx. 30 minutes
Tack-Free Time (8:1, Mixed with WACKER Catalyst T 77, at 23°C)approx. 60 minutes
Viscosity (of the mixture (10: 1), Mixed with WACKER Catalyst T 77, at 25°C, Shear rate 0.5 s⁻¹)approx. 400000 mPa·sDIN EN ISO 3219
Viscosity (of the mixture (10: 1), Mixed with WACKER Catalyst T 77 PLUS, at 25°C, Shear rate 0.5 s⁻¹)approx. 400000 mPa·sDIN EN ISO 3219
Viscosity (of the mixture (10: 1), Mixed with WACKER Catalyst T 77, at 25°C, Shear rate 25 s⁻¹)approx. 75000 mPa·sDIN EN ISO 3219
Viscosity (of the mixture (10: 1), Mixed with WACKER Catalyst T 77 PLUS, at 25°C, Shear rate 25 s⁻¹)approx. 75000 mPa·sDIN EN ISO 3219
Cured Properties
ValueUnitsTest Method / Conditions
Compression Set (at 22 hours, 23°C)7%DIN ISO 815-1 type B method A
Density (in water, at 23°C)0.7g/cm³DIN EN ISO 1183-1 A
Elongation (at break)75%ISO 37 Type 1
Shore Hardness A35DIN ISO 48-4
Tear Strength4.7N/mmASTM D 624 B
Tensile Strength1.2N/mm²ISO 37 Type 1
Uncured Properties
ValueUnitsTest Method / Conditions
Density (at 23°C)0.68g/cm³ISO 1183-1 A
Dynamic Viscosity (at 25°C, Shear rate 0.5 s⁻¹)1200000mPa·sDIN EN ISO 3219
Dynamic Viscosity (at 25°C, Shear rate 25 s⁻¹)120000mPa·sDIN EN ISO 3219
Properties

Uncured:

  • Non-slump paste
  • Medium to fast curing at room temperature
  • To be cured with WACKER® Catalyst T 77 or WACKER® Catalyst T 77 PLUS (recommended mixing ratio: 10:1).

Cured:

  • Medium hardness
  • Primerless adhesion to many substrates (glass, ceramics, metals, plastics and powder coatings).
  • recommended service temperature range: -50 °C to +140 °C
  • Suitable for CIPG and, to a certain degree, for FIPG applications.
Note
  • Cured properties are cured with WACKER Catalyst T 77 or WACKER Catalyst T 77 PLUS, mixing ratio 10:1 (by weight).
  • Curing Conditions: 14 days at 23 °C and 50 % rel. humidity, 2 mm sheet, no post-curing.

Regulatory & Compliance

Safety & Health

Safety Note

While curing ELASTOSIL® RT 773 releases a total of approx. 1.5 - 2 wt.% alcohol. These vapors should not be inhaled for long periods or in high concentrations. Hence ventilation of the work place is recommended.

Packaging & Availability

Country Availability
Regional Availability
  • Africa
  • Asia
  • Europe
  • Latin America
  • Middle East
  • North America
  • Oceania

Storage & Handling

Storage Information

Store in a dry and cool place.