ELASTOSIL^® RT 702

Preparation:

All surfaces must be clean and free of contaminants that will inhibit the cure of ELASTOSIL® RT 702. Examples of inhibiting contaminants are sulfur containing materials, plasticizers, urethanes, amine containing materials and organometallic compounds – especially organotin compounds. If a substrate’s ability to inhibit cure is unknown, a small scale test should be run to determine compatibility.

To reduce the risk of bubbles or void formation during curing, ELASTOSIL® RT 702 can be de-aerated prior to use by applying a vacuum of 25-50 mbar for 10-15 min.

Curing:

ELASTOSIL® RT 702 is a one-part heat-curing silicone, the curing time of which is highly dependent on temperature and on both the size and the heat sink properties of the parts to be bonded. ELASTOSIL® RT 702 is usually cured between 140 °C and 200 °C in order to secure a quick build-up of adhesion to the respective substrates. Typical curing temperatures and resulting curing times are given in adjacent table.

Detailed information about processing one-part heat-curing silicones 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 rubber needs to be rubbed off or removed mechanically, if necessary in combination with a swelling agent (solvent) or a chemical silicone remover.