Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
Core?Shell Engineering of Conductive Fillers towards Enhanced Dielectric Properties: Universal Polarization Mechanism in Polymer Conductor Composites
Flexible dielectric and electronic materials with high dielectric constant (k) and low loss are constantly pursued. Encapsulation of conductive fillers with insulating shells represents a promising approach, and has attracted substantial research efforts. However, progress is greatly impeded due to the lack of a fundamental understanding of the polarization mechanism. In this paper, we study a series of core?shell polymer composites, and investigate the correlation between macroscopic dielectric properties (across entire composites) and microscopic polarization (around single fillers). It is revealed that the polarization in polymer conductor composites is determined by electron transport across multiple neighboring conductive fillers? essentially a domain?type polarization. Formation of core?shell filler structure affects the dielectric properties of polymer composites by essentially modifying the filler?cluster size. Based on this understanding, a novel percolative composite is prepared with higher?than?normal filler concentration and optimized shell's electrical resistivity. The developed composite shows both high?k due to enlarged cluster size and low loss due to restrained charge transport simultaneously, which cannot be achieved in traditional percolative composites or via simple core?shell filler design. The revealed polarization mechanism and the optimization strategy for core?shell fillers provide critical guidance and a new paradigm, for developing advanced polymer dielectrics with promising property sets.This article is protected by copyright. All rights reserved
» Publication Date: 09/11/2022
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
