Aerogel Perfusion-Prepared h-BN/CNF Composite Film with Multiple Thermally Conductive Pathways and High Thermal Conductivity

Hexagonal boron nitride (h-BN)-based heat-spreading materials have drawn considerable attention in electronic diaphragm and packaging fields because of their high thermal conductivity and desired electrical insulation properties. However, the traditional approach to fabricate thermally conductive composites usually suffers from low thermal conductivity, and cannot meet the requirement of thermal management. In this work, novel h-BN/cellulose-nano fiber (CNF) composite films with excellent thermal conductivity in through plane and electrical insulation properties are fabricated via an innovative process, i.e., the perfusion of h-BN into porous three dimensional (3D) CNF aerogel skeleton to form the h-BN thermally conductive pathways by filling the CNF aerogel voids. When at an h-BN loading of 9.51 vol %, the thermal conductivity of h-BN/CNF aerogel perfusion composite film is 1.488 W·m−1·K−1 at through plane, an increase by 260.3%. The volume resistivity is 3.83 × 1014 Ω·cm, superior to that of synthetic polymer materials (about 109~1013 Ω·cm). Therefore, the resulting h-BN/CNF film is very promising to replace the traditional synthetic polymer materials for a broad spectrum of applications, including the field of electronics.

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Improved Thermal Conductivities of Epoxy Resins Containing Surface Functionalized BN Nanosheets

NANO ◽

10.1142/s1793292018501333 ◽

2018 ◽

Vol 13 (11) ◽

pp. 1850133 ◽

Cited By ~ 1

Author(s):

Ling Weng ◽

HeBing Wang ◽

Xiaorui Zhang ◽

Lizhu Liu ◽

Hexin Zhang

Keyword(s):

Thermal Conductivity ◽

Epoxy Resins ◽

Hexagonal Boron Nitride ◽

Electrical Insulation ◽

Coupling Agents ◽

Thermal And Mechanical Properties ◽

Silane Coupling Agents ◽

Silane Coupling ◽

Ep Matrix ◽

Electrical Insulation Properties

The hexagonal boron nitride nanosheets (BN) were firstly treated by silane coupling agents 3-aminopropyltriethoxysilane (KH550) and 3-glycidoxypropyl-trimethoxysilane (KH560) to introduce some amino and epoxy (EP) groups on the BN surface. These modified BN nanosheets were incorporated into an EP matrix to prepare BN@KH560/EP composites with excellent thermal conductivity and electrical insulation properties. Results showed that the thermal conductivity of BN@KH560/EP composite with 20[Formula: see text]vol% BN dosage was found to be 0.442[Formula: see text]W/(m[Formula: see text]K), which was 81% higher than that of pure EP resin. Both BN/EP composites treated by KH550 and KH560 showed rather good electrical insulation properties, although the dielectric constant of BN@KH550/EP composites were slightly higher than BN@KH560/EP composites. Moreover, BN@KH560/EP composites also showed better thermal and mechanical properties than that of BN@KH550/EP composites.

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Generation of Self-Assembled 3D Network in TPU by Insertion of Al2O3/h-BN Hybrid for Thermal Conductivity Enhancement

Materials ◽

10.3390/ma14020238 ◽

2021 ◽

Vol 14 (2) ◽

pp. 238

Author(s):

Kai-Han Su ◽

Cherng-Yuh Su ◽

Po-Wei Chi ◽

Prem Chandan ◽

Cheng-Ta Cho ◽

...

Keyword(s):

Thermal Conductivity ◽

Composite Material ◽

Hot Pressing ◽

Large Scale ◽

Hexagonal Boron Nitride ◽

High Thermal Conductivity ◽

Melt Mixing ◽

Conductive Composite ◽

3D Network ◽

Thermally Conductive

Thermal management has become one of the crucial factors in designing electronic equipment and therefore creating composites with high thermal conductivity is necessary. In this work, a new insight on hybrid filler strategy is proposed to enhance the thermal conductivity in Thermoplastic polyurethanes (TPU). Firstly, spherical aluminium oxide/hexagonal boron nitride (ABN) functional hybrid fillers are synthesized by the spray drying process. Then, ABN/TPU thermally conductive composite material is produced by melt mixing and hot pressing. Then, ABN/TPU thermally conductive composite material is produced by melt mixing and hot pressing. Our results demonstrate that the incorporation of spherical hybrid ABN filler assists in the formation of a three-dimensional continuous heat conduction structure that enhances the thermal conductivity of the neat thermoplastic TPU matrix. Hence, we present a valuable method for preparing the thermal interface materials (TIMs) with high thermal conductivity, and this method can also be applied to large-scale manufacturing.

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Enhanced thermal conductivity of flexible h-BN/polyimide composites films with ethyl cellulose

e-Polymers ◽

10.1515/epoly-2019-0031 ◽

2019 ◽

Vol 19 (1) ◽

pp. 305-312 ◽

Cited By ~ 3

Author(s):

Lin Liu ◽

Siyu Shen ◽

Yiyao Wang

Keyword(s):

Thermal Conductivity ◽

Composite Film ◽

Thermal Conduction ◽

Ethyl Cellulose ◽

Heat Dissipation ◽

Hexagonal Boron Nitride ◽

Flexible Substrate ◽

Thermally Conductive ◽

Polyimide Composites ◽

Enhanced Thermal Conductivity

AbstractThe present work focuses on fabricating a flexible and thermally conductive PI composite film. The PI composite film was obtained by blending hexagonal boron nitride (h-BN) combined with ethyl cellulose and 2,2’-Bis(trifluoromethyl) benzidine (TFMB) functionalized GO (TFMB- GO) in polyimide (PI). The ethyl cellulose successfully formed the thermal conduction network by promoting the dispersion of h-BN in PI matrix. Thus, the thermal conductivity of the PI composite film with ethyl cellulose could be twice than PI film without ethyl cellulose. Besides, the PI composite film containing 30 wt% of h-BN could still exhibit excellent flexibility. Moreover, the combination of TFMB-GO could increase the tensile strength of the PI composite film by up to 80%. Overall, we provided a novel idea for the preparation of flexible substrate materials with efficient heat dissipation which was convenient and possible to apply widely in the industrial production.

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Thermally Conductive and Electrically Insulating PVP/Boron Nitride Composite Films for Heat Spreader

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2380-4491-2019-nor-liu ◽

2019 ◽

Vol 2019 (NOR) ◽

pp. 000001-00005

Author(s):

Ya Liu ◽

Nan Wang ◽

Lilei Ye ◽

Abdelhafid Zehri ◽

Andreas Nylander ◽

...

Keyword(s):

Thermal Conductivity ◽

Boron Nitride ◽

Thermal Management ◽

Hexagonal Boron Nitride ◽

Composite Films ◽

High Thermal Conductivity ◽

Thermally Conductive ◽

Promising Solution ◽

Mechanical Pressing ◽

Insulating Properties

Abstract Thermally conductive materials with electrically insulating properties have been extensively investigated for thermal management of electronic devices. The combined properties of high thermal conductivity, structural stability, corrosion resistance and electric resistivity make hexagonal boron nitride (h-BN) a promising candidate for this purpose. Theoretical studies have revealed that h-BN has a high in-plane thermal conductivity up to 400 - 800 W m−1 K−1 at room temperature. However, it is still a big challenge to achieve high thermally conductive h-BN thick films that are commercially feasible due to its poor mechanical properties. On the other hand, many polymers exhibit advantages for flexibility. Thus, combining the merits of polymer and the high thermal conductivity of h-BN particles is considered as a promising solution for this issue. In this work, orientated PVP/h-BN films were prepared by electrospinning and a subsequent mechanical pressing process. With the optimized h-BN loading, a PVP/h-BN composite film with up to 22 W m−1 K−1 and 0.485 W m−1 K−1 for in-plane and through-plane thermal conductivity can be achieved, respectively. We believe this work can help accelerate the development of h-BN for thermal management applications.

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Effect of aminopropylisobutyl polyhedral oligomeric silsesquioxane functionalized graphene on the thermal conductivity and electrical insulation properties of epoxy composites

RSC Advances ◽

10.1039/c5ra24885j ◽

2016 ◽

Vol 6 (13) ◽

pp. 10498-10506 ◽

Cited By ~ 29

Author(s):

Peisong Zong ◽

Jifang Fu ◽

Liya Chen ◽

Jintao Yin ◽

Xing Dong ◽

...

Keyword(s):

Thermal Conductivity ◽

Polyhedral Oligomeric Silsesquioxane ◽

Interfacial Interaction ◽

Electrical Insulation ◽

High Thermal Conductivity ◽

Epoxy Composites ◽

Functionalized Graphene ◽

Strong Interfacial Interaction ◽

Oligomeric Silsesquioxane ◽

Electrical Insulation Properties

To obtain homogeneous dispersion and strong interfacial interaction in epoxy nanocomposites, an effective approach is proposed to prepare ApPOSS-graphene enhancement epoxy hybrids with high thermal conductivity and electrical insulating property.

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In situ preparation and properties of phthalonitrile resin/hexagonal boron nitride composites

High Performance Polymers ◽

10.1177/0954008320922593 ◽

2020 ◽

Vol 32 (9) ◽

pp. 1010-1018

Author(s):

Xinggang Chen ◽

Yafeng Wang ◽

Zhen Chen ◽

Lifang Zhang ◽

Xiaoming Sang ◽

...

Keyword(s):

Thermal Conductivity ◽

Boron Nitride ◽

Polymer Matrix Composites ◽

Hexagonal Boron Nitride ◽

High Thermal Conductivity ◽

Matrix Composites ◽

In Situ Preparation ◽

Thermosetting Polymers ◽

Novel Approach ◽

Thermally Conductive

Phthalonitrile resin/exfoliated hexagonal boron nitride ( h-BN) composites with high thermal conductivity were fabricated using a novel approach. The route included two steps, micro- h-BN was coated and dispersed by phthalonitrile monomers via the function of heterogeneous nucleation, and then micro- h-BN was exfoliated by heat release during the phthalonitrile curing process. The composites achieved a high thermal conductivity of 0.736W (m·K)−1 containing 20 wt% micro- h-BN, which is 3.17 times higher than that of pure phthalonitrile resin at 0.232W (m·K)−1. Compared to traditional routes, the novel preparation approach requires less BN fillers when improving the same thermal conductivity. Importantly, other thermosetting polymers can also encapsulate BN through this strategy, which paves a new way for preparing thermally conductive thermosetting polymer–matrix composites.

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Enhanced Electrical Insulation and Heat Transfer Performance of Vegetable Oil Based Nanofluids

Journal of Nanomaterials ◽

10.1155/2018/4504208 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 11

Author(s):

Wei Yao ◽

Zhengyong Huang ◽

Jian Li ◽

Liya Wu ◽

Chenmeng Xiang

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Electric Field ◽

Vegetable Oil ◽

Hexagonal Boron Nitride ◽

Thermal Response ◽

Electrical Insulation ◽

High Thermal Conductivity ◽

Heating And Cooling ◽

Cooling Effects

Nanoparticles enhance the electrical insulation and thermal properties of vegetable oil, and such improvements are desirable for its application as an alternative to traditional insulating oil for power transformers. However, the traditional method of insulating nanofluids typically achieves high electrical insulation but low thermal conductivity. This work reports an environmentally friendly vegetable oil using exfoliated hexagonal boron nitride (h-BN) showing high thermal conductivity and high electrical insulation. Stable nanofluids were prepared by liquid exfoliation of h-BN in isopropyl alcohol. With 0.1 vol.% of the nano-oil, the AC breakdown voltage increased by 18% at 25°C and 15% at 90°C. Both the positive and negative lightning impulse breakdown voltages of the nano-oil were also enhanced compared with those of the pure oil. Moreover, the thermal conductivity of the nano-oil increased by 11.9% at 25°C and 14% at 90°C. Given its high thermal conductivity, the nano-oil exhibited faster heating and cooling effects than the pure oil. Nano-oils with an electric field (either DC or AC) displayed a faster thermal response than that without an electric field. The reason is that h-BN is oriented under the electric field and formed a thermal network to increase the heat transfer.

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Enhanced thermal conductivity of polyimide composite film filled with hybrid fillers

High Performance Polymers ◽

10.1177/09540083211000393 ◽

2021 ◽

pp. 095400832110003

Author(s):

Ruiyi Li ◽

Chengcheng Ding ◽

Juan Yu ◽

Xiaodong Wang ◽

Pei Huang

Keyword(s):

Thermal Conductivity ◽

Composite Film ◽

Hexagonal Boron Nitride ◽

Composite Films ◽

Resistance Index ◽

Reference Value ◽

Residual Rate ◽

Practical Applications ◽

Hybrid Fillers ◽

The Matrix

In this article, the polyimide (PI) composite films with synergistically improving thermal conductivity were prepared by adding a few graphene nanoplatelets (GNP) and various hexagonal boron nitride (h-BN) contents into the PI matrix. The thermal conductivity of PI composite film with 1 wt% GNP and 30 wt% h-BN content was 1.21 W(m·k)− 1, which was higher than that of the PI composite film with 30 wt% h-BN content (0.45 W(m·k)− 1), the synergistic efficiency of GNP under various h-BN content (10 wt%, 20 wt%, and 30 wt%) were 1.70, 2.71, and 3.09, respectively. And it was found that the increased h-BN content can suppress the dielectric properties caused by GNP in the matrix. The dielectric permittivity and dielectric loss tangent of 1 wt% GNP/PI composite film were 10.69, 0.661 at 103 Hz, respectively, and that of the 30 wt% h-BN + GNP/PI composite film were 4.29 and 0.1367, respectively. Moreover, the mechanical properties of the PI composite film were suitable for practical applications. And the heat resistance index and the residual rate at 700°C of PI composite film increased to 326.8°C, 74.43%, respectively, and these of PI film were 292.6°C and 59.26%. Thus, it may provide a reference value for applying the filler hybridization/PI film in the electronic packaging materials.

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