Liquid Metal Composite Thermal Interface with Nanoscale Particles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current thermally conductive composites for electronic devices face challenges with brittleness, electrical conductivity under mechanical stress, and dispersion issues, particularly in wearable thermoelectric devices, where high-volume loading of liquid metal particles can lead to unintended electrical paths and reduced thermal transport.
Innovation Solution
A composite material comprising a crosslinked polymeric matrix with surface-functionalized liquid metal particles bonded through amide and/or ester bonds, providing enhanced thermal conductivity and flexibility while maintaining electrical insulation, even under mechanical strain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If high-volume loading of liquid metal particles is used to improve thermal conductivity, then thermal conductivity is improved, but brittleness and poor flexibility increase
Solution Approach 1:
The patent changes the size parameter of liquid metal particles from micrometer scale (~101 μm) to nanoscale (50-500 nm). This parameter change allows high-volume loading (>20 vol%) while maintaining flexibility because the smaller particles can be dispersed throughout the polymer matrix without creating continuous conductive paths that would cause brittleness, yet still provide sufficient thermal conductivity through increased particle-matrix interfacial area.
Solution Approach 2:
The patent creates a composite material system combining nanoscale liquid metal particles with polymer matrix, where the composite achieves properties superior to individual components. The nanoscale particles provide thermal conductivity while the polymer matrix maintains flexibility, and the composite structure prevents particle coalescence that would lead to brittleness.
2Temperature
If high-volume loading of liquid metal particles is used to improve thermal conductivity, then thermal conductivity is improved, but electrical conductivity increases due to particle coalescence
Solution Approach 1:
The patent changes the size parameter to nanoscale (50-500 nm), which prevents particle coalescence under mechanical stress. The small size and high surface-to-volume ratio of nanoscale particles, combined with their dispersion in the polymer matrix, eliminate continuous electrical conductive paths while maintaining thermal conductivity through phonon transport at particle-matrix interfaces.
Solution Approach 2:
The polymer matrix acts as an intermediary that disperses and isolates liquid metal particles, preventing direct particle-to-particle contact that would create electrical conductive paths. The matrix medium allows thermal energy transfer while blocking electrical conduction between particles.
3Ease of manufacture
If micrometer size liquid metal particles are used, then ease of manufacture is improved, but anisotropic deformation under mechanical stress inhibits thermal transport
Solution Approach 1:
The patent changes the size parameter from micrometer to nanoscale, which fundamentally alters the mechanical response. Nanoscale particles (50-500 nm) resist deformation under mechanical stress due to their small size and high surface energy, maintaining spherical morphology and isotropic thermal transport properties even under compression, unlike larger particles that deform into needle shapes.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composite material exhibits improved thermal conductivity and flexibility, with anisotropic thermal conductivity properties that enhance performance in wearable thermoelectric devices, preventing electrical conduction and maintaining insulation under mechanical stress.
Implementation Method 1
the plurality of liquid metal particles and the polymeric material are covalently bonded together by a plurality of amide and/or ester bonds formed from the plurality of carboxylic acid functional groups and the plurality of amino and/or hydroxyl functional groups
Implementation Method 2
the plurality of liquid metal particles form from greater than 20 to 50 vol % of the composite material's volume... the composite material has a thermal conductivity of from 1.0 to 1.5 κ(W/mK)
Data Source
AI summary
Disclosed herein is a composite material comprising a crosslinked polymeric matrix, the crosslinked polymeric matrix formed from a polymeric material comprising a plurality of carboxylic acid functional groups and a plurality of liquid metal particles having a surface functionalized with a plurality of amino and/or hydroxyl functional groups, where the plurality of liquid metal particles and the polymeric material are covalently bonded together by a plurality of amide and/or ester bonds formed from the plurality of carboxylic acid functional groups and the plurality of amino and/or hydroxyl functional groups. Also disclosed herein is a thermal interface layer using said composite material and a thermoelectric device also using said composite material.