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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−1K−1in PVA/defective filler composites is higher than those of ~0.86 ± 0.21 W m−1K−1in 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.
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This content will become publicly available on September 1, 2026
Upcycling Nutshells: Reinforced Polymers and Biocomposites
This review highlights recent advances in the use of nutshell-derived materials, including peanut, walnut, and other lignocellulosic shell wastes, as reinforcers in polymer composites. The focus is placed on evaluating how the incorporation of nutshell fillers influences the mechanical and thermal properties of various polymer matrices. Key findings across multiple studies show that nutshell reinforcement can significantly enhance tensile strength, modulus, thermal stability, and biodegradability, depending on filler concentration, particle size, and surface treatment. The review also discusses the sustainability and economic benefits of using agricultural waste as a functional additive, offering insights into the design of low-cost, eco-friendly polymer composites for packaging, construction, and environmental applications.
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- Award ID(s):
- 2203669
- PAR ID:
- 10650105
- Publisher / Repository:
- mdpi
- Date Published:
- Journal Name:
- Sustainable Chemistry
- Volume:
- 6
- Issue:
- 3
- ISSN:
- 2673-4079
- Page Range / eLocation ID:
- 25
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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