ELASTOSIL® R plus 4370/40
ELASTOSIL® R plus 4370/40 is an addition-curing, self-bonding two-component high consistency silicone rubber for the manufacture of extruded articles.
ELASTOSIL® R plus 4370/40 is a self-adhesive grade which adheres to various plastic substrates (e.g. PA, PBT) and metals without tack formation to the mold. The bonding properties can be improved by a post-curing process (e.g. one hour at 100 °C) or by a longer storage at room temperature. Because of the individual surface properties each substrate must be tested before serial production. The vulcanizates are transparent and noted for good mechanical and electrical properties. Thanks to addition cure, the vulcanization reaction is significantly faster compared to peroxide curing materials. No peroxide decomposition products are formed during vulcanization.
At service temperatures above approx. 180 °C the addition of heat stabilizers is recommended. Further information about an improvement of the heat stability by use of specific ELASTOSIL® AUX Heat Stabilizers can be obtained from the Technical Information Sheet "ELASTOSIL® AUX Stabilizers H" or the latest edition of our brochures.
Specific features of ELASTOSIL® R plus 4370/40
- Addition Curing
ELASTOSIL® R plus 4370/40 is suited for the manufacture of 2-composite combinations via pressure free extrusion or co-extrusion.
ELASTOSIL® R plus 4370 may not be cured with peroxides but only with the platinum catalyst batch ELASTOSIL® AUX Batch PT 1. ELASTOSIL® R plus 4370/40 and ELASTOSIL® AUX Batch PT 1 are mixed homogeneously on a roll mill in a ratio of 100:1.5. A higher catalyst dosage results in a faster curing but a reduced pot life. Care must be taken to keep the compound cool during mixing. A homogeneous incorporation is a must, but the temperature of the rubber should not exceed 30 °C, otherwise there is a risk of scorch.
The cross linking reaction starts as soon as ELASTOSIL® AUX Batch PT 1 has been added. The rate and degree of crosslinking is dependent on storage time and temperature. At 23 °C the pot life is approximately 24 h. This can be extended by storing the catalyzed mixture at lower temperature.
For detailed information please refer to the latest edition of our brochure "SOLID AND LIQUID SILICONE RUBBER - MATERIAL AND PROCESSING GUIDELINES".
This product is available in 20 kg and 540 kg cardboard packaging.
Special delivery forms are possible but depend on several technical and commercial aspects. Please contact your local sales manager in such cases.
Please store the cardboard boxes in a dry and cool place. Once opened, cardboard boxes should always be resealed after use to prevent the platinum catalyst from being poisoned by amines, sulphur or phosphorus compounds. 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.