Enhancing a multi-field-synergy process for polymer composite plasticization: A novel design concept for screw to facilitate phase-to-phase thermal and molecular mobility

摘要

A contemporary concept for screw designs has been proposed in relationship with multi-field-synergy in polymer plasticization with composites to facilitate phase-to-phase thermal and molecular mobility; subsequently a torsion configuration has been designed, manufactured and validated by both numerical modelling and experimental data. This new screw design allows an innovative and effective method to resolve a growing challenge in polymer process engineering, specifically regarding nanocomposites processing, i.e., an inadequate control of mass transfer and thermal management for Nano-filler or biopolymer melt flows through narrow channels during extrusion or injection. The adaption of torsional flow facilitated the mass and thermal distribution in composites of dissimilar polymer mixes. The multi-field-synergy analysis reveal that the pressure loss is interrelated with the interaction between velocity and velocity gradient. In addition, the convective heat transfer was found to be correlated with the interaction between velocity and temperature gradient. The temperature gradient is inversely proportional to the shear rate and is influenced by the interaction between temperature gradient and shear rate. The simulation and experimental results state clearly that screw with torsion configuration enhanced heat transfer, improved mixing performance and obtained a more uniform temperature distribution than that of a conventional screw without torsion and can significantly improve processing of composites in general.