Composites are specialty plastics in which thermoset polymers (such as phenolic, polyester and epoxy resins) are reinforced with carbon, glass or mineral fibers. Parts made from this material offer a number of outstanding properties: low weight, high mechanical strength and excellent design flexibility.

These properties have led to a rise in demand for such parts in recent years. Today, for example, rotor blades for wind turbines, spoilers for Formula 1 racing cars, aircraft noses and boat hulls are made from composite materials. These high-tech applications place very high demands on the manufacturing process, which necessitates constant improvements to the processing methods involved.

With ELASTOSIL^® C, WACKER has now developed a reusable system solution that makes the manufacturing process both efficient and more cost-effective. Parts made from composites can be manufactured in closed-mold or open-mold processes. In an open-mold process, such as vacuum bagging, the fiber material is placed on a half-shell mold. This is sealed with a flexible vacuum film that is normally made from polyamide or polyethylene and is attached at the bottom of the mold. The film hugs the fiber material closely and faithfully reproduces every detail.

ELASTOSIL^® allows you, for example, to manufacture your own reusable vacuum “bags” to the precise shape you desire. ELASTOSIL^® C is a two-part, platinum-curing low-viscosity silicone rubber that comes in different grades and cures in just a few minutes at room temperature, without shrinking. ELASTOSIL^® makes it possible to produce a reusable, precision-fit, fabric-reinforced silicone vauum bag by a spray-up or lay-up method in next to no time.

Once made, this silicone bag can be placed quickly and securely over the mold before each part is produced. Repeated, time-consuming sealing with conventional vacuum film before each part is no longer necessary. This therefore reduces disposal, labor and material costs.