ELASTOSIL^® RT 723 A/B

Important!

Only A and B components with the same batch number should be processed together!

Surface preparation:

All surfaces must be clean and free of contaminants that will inhibit the cure of ELASTOSIL^® RT 723 A/B. 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.

When a substrate is known to pick up ambient moisture, e.g. as technical polyamide grades usually do, it is recommended to reduce the level of absorbed humidity by drying the substrate at 120 °C prior use. This minimizes the risk of bubble formation at the silicone/substrate interface during the curing process.

Mixing:

Caution ! Component A of ELASTOSIL^® RT 723 A/B contains the platinum catalyst, component B comprises the crosslinker. Since even traces of platinum catalyst may cause gelling of component B, all tools (e. g. spatula, stirrers, mixing cups etc.) used for handling either component A or the A/B mix must not come into contact with component B by mistake.

The two components should be thoroughly mixed at a 1 : 1 ratio by weight or volume, preferably by automatic metering lines equipped with static or dynamic mixing devices.

Curing:

The curing time of addition-curing silicone rubber is highly dependent on temperature, size and heat sink properties of the respective substrates or of the assembly parts to be bonded, respectively. In order to secure a quick build-up of adhesion to the substrates, ELASTOSIL^® RT 723 A/B is vulcanized between 120 °C and 200 °C usually. Typical curing temperatures and resulting curing times are given in adjacent table.

Detailed information about processing 2-part addition-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.