ELASTOSIL® LR 5040/70 A/B is a paste-like, easily pigmentable two-component liquid silicone rubber with very low volatiles content and excellent mechanical properties with no required post-cure. Articles made from ELASTOSIL® LR 5040/70 A/B exhibit high transparency, excellent electrical properties, and mechanical properties engineered for high tear resistance according to DIN ISO 34-1 A (trousers) and ASTM D 624 B (crescent) without post-curing. The ability to meet regulatory requirements for specific food and baby care applications without need for post-curing offers key advantages in cost-savings and productivity.


Narrow Shore hardness range from 67 to 73 Shore A (70 ± 3 Shore A) without post-curing.

Specific features of ELASTOSIL® LR 5040/70 A/B

  • Fast curing
  • Food-contact
  • High tear-resistant
  • Low volatile

ELASTOSIL® LR 5040/70 A/B is designed for the automated, high volume production of injection moulded articles.

Properly cured vulcanizates of ELASTOSIL® LR 5040/70 A/B can be used for food contact applications and are suitable for use under the Recommendation "XV. Silicones" of the BfR and FDA 21 CFR §177.2600 "Rubber Articles Intended for Repeated Use" considering any given limitations on extractable and volatile substances.

Properly cured materials meet the limit of 0.5 % for volatile substances in accordance with BfR “XV. Silicones”, DIN EN 1400:2014-07 and DIN EN 14350-2:2004-11, respectively. Consequently, post-curing may not be necessary, however, as the results may vary with the processing conditions and the geometry of the finished article, it is the responsibility of the person placing the article on the market to verify compliance with all relevant requirements and regulations. Since the measured volatile content increases with decreasing thickness of a part, in particular very thin-walled articles have to be carefully checked for compliance with any relevant limitations for volatile matter.


The following studies were performed on vulcanizates of ELASTOSIL® LR 5040/70 A/B according to ISO 10993:
    - Hemocombatibility (Hemolysis and Thrombogenicity) (ISO 10993-4)
    - Cytotoxicity (ISO 10993-5)
    - Sensitation LLNA (ISO 10993-10)
    - Pyrogenicity (ISO 10993-11)

The following studies were performed on vulcanizates of ELASTOSIL® LR 5040/70 A/B according to USP class VI:
    - Acute systemic toxicity
    - Intracutaneous toxicity
    - Implantation test
No adverse effects have been detected at any of the studies performed.

The A and B components are delivered ready to use in 20 kg pail and 200 kg drum kits. With adequate metering equipment, they can be pumped directly from the original containers into the injection molding machine and mixed by a static mixer. The mixing ratio is 1 : 1. At room temperature, mixtures of A and B components have a pot life of at least one day.



This product is available in 20 kg pail and 200 kg drum kits.


Once opened, containers should always be resealed after use to prevent the platinum catalyst from being poisoned by amines, sulphur or phosphorus compounds. For detailed information about storage conditions please refer to the latest edition of our brochure "SOLID AND LIQUID SILICONE RUBBER - MATERIAL AND PROCESSING GUIDELINES".
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

Wacker Chemical Corporation
3301 Sutton Road
Adrian, MI 49221-9397
United States
+1  888  922-5374 (Phone)

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