The objective of this SEED study is to evaluate a proof-of-concept to extend the capability of expired polymeric materials (including composite prepreg and adhesives) via modification of processing conditions (time, temp, rate, pressure) in response to real time assessment of the material state. Determination of the required processing changes will be supported by advanced polymer processing simulation software and experimental material data to ascertain the true shelf-life of expired materials. If successful, this approach will enable re-purpose of expired prepregs and adhesives used in advanced composite manufacturing and repair while producing parts meeting aircraft Original Equipment Manufacturing (OEM) design specifications. More importantly, it would help reduce the environmental impacts and disposal costs of hazardous waste generated in Department of Defense (DoD) composite manufacturing and repair processes and reduce worker exposure to dangerous chemicals generated in waste disposal operations.
This effort focuses on how to re-purpose expired composite materials (prepregs and adhesives) while producing parts that are within manufacturer’s specifications. A proof-of-concept approach will be used that combines processing simulations and input experimental data, which will provide key information on whether in-specs parts can be produced by modifying the established processing parameters. This project will leverage the processing simulation capabilities of RAVEN to develop alternate process parameters taking into account that the initial resin forms are not in an initial uncured state. In this manner, alternative process routes can be devised to produce a composite with usable properties from tentatively expired “waste” materials. This approach in turn can increase the processing efficiency while reduce hazardous waste streams (and associated disposal costs), reduce worker’s exposure to hazardous chemicals, and reduce the overall environmental impact while saving material costs for the DoD.
The benefits to the DoD are multi-fold, including a reduction in lifecycle costs associated with the manufacturing and repair of DoD weapons systems. These are significant DoD problems that are applicable to aircraft OEM’s as well as DoD air vehicle composite repair facilities across the Services. The environmental costs associated with disposal of toxic waste is significant. It has been reported that millions of pounds of waste associated with the composite manufacturing process could be repurposed to alternative uses or recycled.