Defects vibrations engineering for enhancing interfacial thermal transport in polymer composites.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39841839.
- Also identified by DOI 10.1126/sciadv.adp6516 and PMC identifier 11753404.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
To push upper boundaries of thermal conductivity in polymer composites, understanding of thermal transport mechanisms is crucial. Despite extensive simulations, systematic experimental investigation on thermal transport in polymer composites is limited. To better understand thermal transport processes, we design polymer composites with perfect fillers (graphite) and defective fillers (graphite oxide), using polyvinyl alcohol (PVA) as a matrix model. Measured thermal conductivities of ~1.38 ± 0.22 W m<sup>-1</sup> K<sup>-1</sup> in PVA/defective filler composites is higher than those of ~0.86 ± 0.21 W m<sup>-1</sup> K<sup>-1</sup> in PVA/perfect filler composites, while measured thermal conductivities in defective fillers are lower than those of perfect fillers. We identify how thermal transport occurs across heterogeneous interfaces. Thermal transport measurements, neutron scattering, quantum mechanical modeling, and molecular dynamics simulations reveal that vibrational coupling between PVA and defective fillers at PVA/filler interfaces enhances thermal conductivity, suggesting that defects in polymer composites improve thermal transport by promoting this vibrational coupling.