A newly developed rapid-cure, self-adhesive liquid silicone rubber (LSR) designed for two-component injection molding forms a firm bond with polycarbonate without pretreatment of the surface. The LSR enables cost-effective large-scale production of multi-component parts used in the medical device, automotive, and other sectors. Wacker will introduce the Elastosil LR 3078 series at K 2022 in October.
The grades in the Elastosil LR 3078 series are formulated such that chemical adhesion builds up to the substrate during curing but not to the injection molding tool. The patented self-adhesive technology does not contain any bisphenol A structures, and the grades do not contain any substances that could result in solid deposits forming in the mold during processing.
The LSR’s rapid curing rate enables short injection molding cycle times. In addition, devices with complicated geometric shapes can be produced with high precision and without the need for secondary finishing. Thus, Elastosil LR 3078 opens the way for further miniaturization of polycarbonate-silicone hybrid parts and for completely new product designs, said Wacker.
Image courtesy of Wacker
|Elastosil LR 3078 is suited for the manufacture of multi-component medical devices such as respiratory masks.|
The product portfolio encompasses hardnesses from 20 to 70 Shore A, and all grades are translucent and can be colored to customer specifications. Compression set is very low, making the material suitable for sealing applications. When relaxed after high-temperature compression, parts molded with Elastosil LR 3078 will show minimal deformation thanks to the material’s elasticity. As a result, sealing lips will retain long-term functionality.
Cured Elastosil LR 3078 products have passed selected tests for biocompatibility according to ISO 10993 and USP Class VI. They can also be steam sterilized repeatedly at 134°C with no loss of mechanical properties or adhesion to polycarbonate.
Applications range from transparent covers in automotive applications, housing covers for household appliances, and systems for medical diagnostics, automated drug delivery, and minimally invasive diagnostic and surgical devices.
Wacker will exhibit in hall 6 at booth A10 at K 2022 in Düsseldorf, Germany, from Oct. 19 to 26.