Title: ENABLING RECYCLING OF COMPOSITES: UNDERSTANDING THE IMPACTS OF MULTIPLE THERMAL PROCESSING CYCLES
Authors: Roo Walker, Daniel Webb, Matthew Korey, Samarthya Bhagia, Nathan Black, Ally Collier, Soydan Ozcan, Vlastimil Kunc, Chad Duty
Abstract: When considering the utilization of recycled short carbon fiber feedstock materials for advanced manufacturing, understanding the material degradation behavior is essential in determining how many times a composite material can be effectively reprocessed and remanufactured. This study characterizes the degradation behavior of short carbon fiber acrylonitrile butadiene (CF-ABS) that has been reprocessed five times with twin screw extrusion. Parallel plate rheology was completed to observe the degradation in complex viscosity of the recycled feedstock materials. Gel permeation chromatography (GPC) was utilized to characterize the changes in molecular weight distribution of the recycled materials as a result of thermal and mechanical degradation during the re-processing steps. Rheological characterization, GPC, and twin-screw processing data help inform the process optimizations required to process the recycled feedstock material. Successful characterization of the degradation behavior of short fiber composite feedstock materials aids in increased understanding of the lifespan of high value carbon fiber composite materials and aids in process optimization of recycled composite materials.
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Conference: SAMPE 2023
Publication Date: 2023/04/17
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