Design, Manufacture, and Characterization of Composites Using On-Line Recycled Thermoplastic Powder Impregnation of Fibers and In-Situ Filament Winding

Abstract

Recycled thermoplastic powder impregnated composites using in-situ filament winding and on-line consolidation of fibers have been successfully manufactured with the modified filament winding setup constructed in this study. Reclaimed low density polyethylene (RLDPE), reclaimed low-density polyethylene with polymer additives consisting of 0.25% by weight of Cyasorb® UV-3346 Light Stabilizer, 0.25% by weight of Cyasorb® UV-53 1 Light Stabilizer, and 0.08% by weight of Cyanox® 2777 Antioxidant (RLDPE-PA), and virgin low-density polyethylene (LDPE) were pulverized to ultrafine powders ranging from 20 to 300,um, and utilized to impregnate a separated fiberglass tow. After initial experiments, two powder-impregnated composite tubes were manufactured for each thermoplastic material system. The composites were then tested for tensile (hoop) strength and compressive bending strength under the ASTM D2290-95 and C-ring tests, respectively. This study showed that while the RLDPE composite did not perform well, composite samples made with RLDPE and polymer additives (i.e.. RLDPE-PA) performed better than RLDPE samples but not as well as composites made of virgin LDPE. The impregnation and consolidation steps in the manufacturing process were also effective for all three systems. The composite tubes exhibited very low void contents and high fiber volume fractions, while unmelted and unconsolidated thermoplastic powders were not present in the manufactured parts. The absence of fiber waviness and fiber migration through the thickness of the composite demonstrates that the online consolidation of powder-impregnated fibers was also effective. The collection of the separated powder-impregnated fibers prior to filament winding also seemed to be sufficient.