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Dielectric Elastomers with Liquid Metal and Polydopamine-Coated Graphene Oxide Inclusions.

ABSTRACT: Suspending microscale droplets of liquid metals like eutectic gallium-indium (EGaIn) in polydimethylsiloxane (PDMS) has been shown to dramatically enhance electrical permittivity without sacrificing the elasticity of the host PDMS matrix. However, increasing the dielectric constant of EGaIn-PDMS composites beyond previously reported values requires high EGaIn loading fractions (>50% by volume) that can result in substantial increases in density and loss of material integrity. In this work, we enhance permittivity without further increasing EGaIn loading by incorporating polydopamine (PDA)-coated graphene oxide (GO) and partially reduced GO. In particular, we show that the combination of EGaIn and PDA-GO within a PDMS matrix results in an elastomer composite with a high dielectric constant (∼10-57), a low dissipation factor (∼0.01), and rubber-like compliance and elasticity.

SUBMITTER: Hu Y

PROVIDER: S-EPMC10214383 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Dielectric Elastomers with Liquid Metal and Polydopamine-Coated Graphene Oxide Inclusions.

Hu Yafeng Y Majidi Carmel C

ACS applied materials & interfaces 20230515 20

Suspending microscale droplets of liquid metals like eutectic gallium-indium (EGaIn) in polydimethylsiloxane (PDMS) has been shown to dramatically enhance electrical permittivity without sacrificing the elasticity of the host PDMS matrix. However, increasing the dielectric constant of EGaIn-PDMS composites beyond previously reported values requires high EGaIn loading fractions (>50% by volume) that can result in substantial increases in density and loss of material integrity. In this work, we en ...[more]

PMID: 37184064

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