Munich-based chemical group Wacker at COMPAMED showcased its new ELASTOSILLR 5040 line of liquid silicone rubber grades. These silicone products fulfill the stringent regulatory requirements that apply to silicone articles in many medical-technology applications.

Cured rubber products made of ELASTOSIL LR 5040 feature excellent mechanical properties, even without thermal post-treatment, and contain very few volatile substances. This allows manufacturers to eliminate the postcuring step after fabrication in many cases. 

ELASTOSILLR 5040 cures to a translucent elastomer whose volatiles content – without thermal post-treatment – is below 0.5 weight percent. In its non-postcured state, the silicone exhibits a high level of tear resistance equivalent to that of postcured high-tear- strength standard materials. As a result, it can withstand such mechanical stresses as may occur in the usage of medical devices, for example.

These properties make ELASTOSILLR 5040 the material of choice when manufacturers want to dispense with thermal post-treatment altogether. Typical applications include anti-colic valves, bottle tops or respirator masks.

The product line will initially cover a hardness range from 30 to 70 Shore A. In the cured state, the actual hardness of the non-postcured silicone deviates from specification by only ±3 points. ELASTOSILLR 5040 can be readily processed by injection molding. Since molded parts no longer have to be postcured in many cases, production processes can be greatly streamlined and automated to a high degree. This facilitates very rapid, efficient and cost-effective large-scale production, even under cleanroom conditions.

COMPAMED took place in Düsseldorf, Germany, from Nov. 13 to 16, 2017. Wacker was in Hall 8A, at Booth D28.