Enhancing Mixing and Thermal Management of Recycled Carbon Composite Systems by Torsion-Induced Phase-to-Phase Thermal and Molecular Mobility

Abstract

A novel torsion screw has been proposed to resolve the inadequate control of mass transfer and the thermal management of two component polymer blends and their carbon fiber composites. The novel torsional screw distinctly introduced radial flow in the torsion screw channel, which is a significant improvement over the flow pattern developed by the conventional screw. The heat transfer and mixing behavior of melt mixtures are enhanced by adapting screws with torsion elements compared with the traditional screw elements. Heat transfer efficacy in the polypropylene–polystyrene bi-phasic extrusion process improved with the increase in torsion element numbers. An increased number of newly designed torsional elements also improved the dispersion of minor phase in bi-phase polypropylene–polystyrene composition and their carbon fiber composites. The unique flow pattern induced by the torsion elements shows a synergistic effect on the melt-phase mass flow and the thermal flow field facilitating phase-to-phase thermal and molecular mobility and enhanced fiber orientation, crystallinity and mechanical properties of composite made from recycled carbon fiber/polypropylene. Microtomographs of recycled carbon fiber demonstrated the extraordinary ability of a torsion screw element to orient carbon fiber in both axial and radial directions.

Control of the Shear Strain in the Homogenization Zone of the Disk Extruder

“…Article [5] analyzes the impact of different types of static mixers using two criteria: energy consumption and compactness. Energy consumption was determined by the value of the pressure drop, and compactness by the length of the mixer.…”

Polymeric field synergy principle: Revealing the intrinsic mechanism of screw channel optimization to enhance thermal management and process efficiency

“…In this paper, a theoretical analysis of extrusion process was carried out, delving into the interrelationships among velocity field, velocity gradient field, and temperature gradient field [15], and the polymeric field synergy principle was proposed to elucidate the intrinsic mechanisms of heat and mass transport in the molten polymer during the extrusion process [16]. In order to validate the scientific validity of the proposed theory, four representative unconventional novel screws, widely used in industry, were selected to analyze and compared them with a standard screw.…”