Exfoliated Boron Nitride Composite Thermal Management
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Solution Overview
Problem
Current thermal management solutions for electronic and opto-electronic devices, such as LED bulbs, face challenges with inefficient heat dissipation due to the limited thermal conductivity of traditional materials like plastics and the high cost and weight of aluminum heat sinks, while boron nitride composites suffer from poor interface wetting and high costs.
Innovation Solution
The development of a thermally conductive composition comprising exfoliated boron nitride produced in situ within a resin matrix using a blended filler composition that includes boron nitride, a hard filler material, and a silane additive, such as thiocarboxylate or blocked mercapto silane, to enhance thermal conductivity without separate exfoliation steps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If aluminum heat sinks are used for LED thermal management, then thermal conductivity is improved, but weight and cost increase significantly
Solution Approach 1:
The patent uses composite materials by combining plastic matrix with boron nitride filler particles to create a material that achieves high thermal conductivity (comparable to aluminum) while maintaining the lightweight advantage of plastics. The composite structure allows heat dissipation through the thermally conductive boron nitride particles dispersed in the plastic matrix.
Solution Approach 2:
The patent changes the thermal conductivity parameter of the plastic material by incorporating boron nitride filler at specific concentrations and aspect ratios. This parameter modification transforms the inherently poor thermal conductor (plastic) into an effective heat dissipation material without changing the fundamental lightweight characteristic.
2Temperature
If boron nitride is added to plastic to improve thermal conductivity, then thermal management is enhanced, but cost increases due to high boron nitride pricing
Solution Approach 1:
The patent applies local quality by using aspect ratio control of boron nitride particles to create efficient heat conduction pathways. High aspect ratio platelets (greater than 2:1) provide better thermal conductivity per unit volume, allowing reduced filler loading while maintaining performance. This targeted approach optimizes the local arrangement of filler particles to maximize thermal efficiency and minimize material cost.
Solution Approach 2:
The patent modifies the aspect ratio parameter of boron nitride particles as a key control variable. By specifying minimum aspect ratios greater than 2:1, the patent achieves enhanced thermal conductivity at lower filler concentrations, directly addressing the cost issue while maintaining thermal performance requirements.
3Temperature
If high aspect ratio boron nitride particles are used to enhance thermal conductivity, then heat dissipation is improved, but processing difficulty increases
Solution Approach 1:
The patent applies preliminary action by pre-sieving boron nitride particles to select and isolate high aspect ratio platelets before compounding. This pre-processing step ensures that only particles meeting the minimum aspect ratio criterion are used, guaranteeing optimal thermal conductivity while simplifying the downstream processing by eliminating the need for complex in-process sorting or selection mechanisms.
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
This approach achieves higher thermal conductivities and improved physical properties, reducing costs and weight, while maintaining electrical insulation, thus effectively addressing the thermal management challenges in electronic devices.
Implementation Method 1
Boron nitride is also very inert and not easily wetted by resins. This leads to imperfect interfaces and large thermal resistances between the filler and matrix
Implementation Method 2
a silane as functionalization additive
Implementation Method 3
the in-plane thermal conductivity of the boron nitride/plastic composite is only around 2-10 W/mK even at high loadings of boron nitride
Implementation Method 4
mixing boron nitride crystals into a resin material in the presence of a material having a Mohs hardness greater than the Mohs hardness of (non-exfoliated) crystalline boron nitride material results in exfoliation of the boron nitride crystals
Data Source
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AI summary
A composition comprising exfoliated boron nitride crystals dispersed in a resin matrix and a method of forming such compositions comprises the in situ exfoliation of boron nitride crystals by compounding boron nitride crystals in a resin material with a hard filler material having a hardness greater than the hardness of the boron nitride crystals.