ELASTOSIL® RT 722 RB A/B
ELASTOSIL® RT 722 RB A/B is a thixotropic, thermally curable, addition-curing two-component silicone sealing adhesive that cures to an elastomer.
- Fast curing at moderate temperature
- Thixotropic, pasty
- Medium hardness
- Primerless adhesion on many substrates
- High tensile strength and high elongation
- D4-D8 < 350ppm
- Sealing adhesive for electronic control units
- FIPG applications for plastic and metal housings
- Dam material for dam-and-fill applications
- Sealing and gasketing of housings
ELASTOSIL® 722 RB A/B shows good primerless adhesion to many substrates.
We recommend running preliminary tests to optimize conditions for the particular application.
Comprehensive processing instructions are given in our leaflet „ Room Temperature Vulcanizing (RTV) Silicones (Materials and Processing Guidelines)” which can be downloaded from WACKER Chemie AG website.
All equipment and surfaces must be clean and free of contaminants that will prevent adhesion and/or inhibit the cure of ELASTOSIL® 722 RB A/B
Separation layers on bonding substrated may be formed from residues of previous processes, from migrating additives or unintended contaminations. Examples of separating molecules among others can be processing fluids or deforming agents that are not able to built chemical links to reactive and accessible anchor groups of the substrate surface or to the silicone elastomer.
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 or built up adhesion is unknown, a small scale test should be run to determine compatibility.
ELASTOSIL® 722 RB A/B shows good primerless adhesion to many substrates. We recommend to run preliminary tests to optimize conditions for the particular application.
Safeguarding of reproducable and suitable surface quality is recommended. State of the art methods include in-line surface pretreatments like plasma processes or laser pretreatment.
Because of the high thixotropy (shear thinning effect)
ELASTOSIL® 722 RB A/B can be dispensed easily with all dispensing equipments using static mixing tubes or dynamic mixing.
Since silicones dissolve notable amounts of air, an in-line degassing is recommended.
ELASTOSIL® 722 RB A/B works best when cured at 115 °C or more.
Curing time should be adapted to the size and heat sink properties of the components and parts.
The term "curing" time describes the time needed for solidification of the material.
For typical substrates adhesion built-up is accomplished within this time, which can be observed by cohesive failure upon adhesion test.
However, depending on the surface quality of the bonding surfaces, time to adhesion might differ from given curing profiles.
In the interest of robust processing it is highly recommended that for selected curing temperatures & times aging tests on specific customers parts are carried out to safeguard the process.
The 'Best use before end' date of each batch appears 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.