ELASTOSIL® RT 772
ELASTOSIL® RT 772 is a flowable, condensation curing RTV-2 silicone for potting and coating applications. When processed with a curing agent of the WACKER® Catalyst T 77 series, a self-bonding and durable silicone rubber is formed.
Cured ELASTOSIL® RT 772 shows long-term stability against weathering, moisture and UV light. The silicone elastomer may continously be exposed to constantly changing climatic conditions, UV radiation and temperatures as high as 230 °C (446 °F) without damage.
Properties
Uncured:
- High extrusion rate
- Flowable
- 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)
- Outstanding heat resistance
- recommended service temperature range: -50 °C to +230 °C
- UL 94 HB listed (when cured with WACKER® Catalyst T 77)
Specific features of ELASTOSIL® RT 772
- Condensation-curing
- Electrically insulating
- Heat resistant
- Low viscosity
- Self-adhesive
- Steam resistant
- Two-component
- UV & weathering-resistant
Data sheets
- General purpose sealing and potting grade
- Typical fields of application: household appliances, automotive, mechanical engineering, electrical industry.
Mixing and curing:
ELASTOSIL® RT 772 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 772) 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 very high temperature without damage. Cured ELASTOSIL® RT 772 usually shows good primerless adhesion to many substrates, e.g. glass, ceramics, metals, plastics and powder coatings.
Detailed information about processing and modifying curing speed is given in our brochure “ROOM TEMPERATURE VULCANIZING (RTV) SILICONES - MATERIAL AND PROCESSING GUIDELINES”. We recommend running preliminary tests to optimize conditions for the particular application.
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).
Storage
Store in a dry and cool place.
The 'Best use before end' date of each batch is shown on the product label.
Storage beyond the date specified on the label does not necessarily mean that the product is no longer usable. In this case however, the properties required for the intended use must be checked for quality assurance reasons.
Sales and support
Ann Arbor, MI 48108
United States
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