At FAKUMA, WACKER showcases high-performance silicones for the food, healthcare and automotive industries

Self-adhesive liquid silicone rubber grades allow hard/soft composite components to be produced very efficiently in large-scale production runs. Ideally, the hard component can thus be overmolded with liquid silicone rubber in the injection molding machine without any surface treatment. This facilitates the cost-effective mass production of composite parts based on thermoplastic or metal materials.

This feature also applies to ELASTOSIL^® LR 5471. The self-adhesive liquid silicone rubber, which WACKER is unveiling for the first time at FAKUMA, achieves excellent adhesion on metals and thermoplastics. Moreover, the product complies with the guidelines of the German Federal Institute for Risk Assessment for silicones and other regulations regarding food contact and babycare applications without thermal post-treatment.

Another advantage is the product’s mechanical performance. ELASTOSIL^® LR 5471 exhibits an elongation at break of up to 570 percent and a tear strength of 38 N/mm (according to ASTM D 624 B) without postcure treatment. Parts provide sufficient elasticity and mechanical strength for mechanically highly demanding food contact and sensitive applications. Examples include gaskets and flexible scrapers for cookware, baking and kitchen utensils, medical applications and soft components for pacifiers and baby bottles. The product is available in Shore A hardness grades 40 and 50 and is particularly well-suited for the large-scale production of overmolded parts and for co-molding procedures.

Michael Kalchauer, head of WACKER’s Process Technology Center at the company’s Burghausen site, will share highlights of the new liquid silicone rubber during his presentation at FAKUMA’s East Conference Center (Berlin Room) on Tuesday, October 13, at 2:20 p.m.

WACKER will also be presenting ELASTOSIL^® LR 3822, an oil-exuding liquid silicone rubber with coolant resistant properties. It was specifically designed for applications in the field of e-mobility with a focus on connector seals in the cooling circuit of EV traction batteries. Molded parts made of the new liquid silicone rubber show a low compression set and high resilience. This makes it possible to manufacture sealing elements with high sealing performance.

ELASTOSIL^® LR 3822 continuously releases silicone oil from its surface. This creates a lubricant film that facilitates the machine assembly of molded parts significantly. The silicone is also extremely durable and tear-resistant. After curing, the silicone rubber can be stretched by 270 percent without cracks or damage. Another advantage is its superior low-temperature flexibility. The elastomer retains its elasticity even at temperatures as low as –45 °C.

The new liquid silicone rubber is the first oil-exuding product that also offers high coolant resistance. Tests show that the silicone maintains most of its mechanical properties even after being stored for 1,000 hours in a glycol-water mixture at 125 °C. With a compression set of 44 percent, sealing elements made of ELASTOSIL^® LR 3822 have sufficient resilience to ensure a consistently high level of sealing performance in the seal groove during operation.

At FAKUMA, WACKER will also provide an overview of its additive portfolio. The focus is on additives and processing aids under the GENIOPLAST^® and GENIOPERL^® brands. GENIOPLAST^® additives are designed for conventional compounding processes and improve the processability, surface quality, and mechanical properties of polyolefin compounds, engineering plastics, and thermoplastic elastomers. GENIOPERL^® high-performance tougheners are engineered specifically for epoxy and vinyl ester systems. Their sophisticated architecture based on a functional silicone building block ensures clean dispersion, high compatibility, and efficient phase separation during curing. This results in significantly improved impact resistance, damage tolerance, adhesion and low-temperature toughness, all while keeping viscosity and glass transition temperature virtually unchanged.