Shape Memory Polymer Bladder Tooling

Cornerstone Research Group Inc. (CRG) proposes to demonstrate the benefits of shape memory polymer (SMP) bladder tooling for out-of-autoclave composite fabrication. CRG’s SMP bladder tooling is a cutting edge technology that reduces labor costs and manufacturing time for fabricating complex composite parts. Conventional silicone or latex bladders are not rigid enough to support composite lay-up before custom molding. Often material must be applied to the inside of a female mold first, an inflatable bladder inserted, the mold closed, and the bladder pressurized and inflated to consolidate the material against the mold surface. This process is labor intensive, can produce seams, wrinkles and bridging, and often results in inaccurate part shapes. These drawbacks have led to the theory of an inflatable bladder core used as the mandrel, but conventional bladder cores lack the structural integrity required for the composite lay-up process. SMP bladders operate both as rigid mandrels and inflatable bladder cores initially providing a rigid, durable surface for composite lay-up, then flexibility and inflatability when the part is formed against the interior of the final mold.