Uniaxially stretched polyethylene/boron nitride nanocomposite films with metal-like thermal conductivity

Abstract

Achieving ultra-high thermal conductivity while maintaining the electrical insulation of polymers is highly desirable for many applications such as thermal management and packaging. In this work, polyethylene / boron nitride nanoplatelets (PE/BNNP) nanocomposite film was produced through melt processing followed by uniaxial stretching. Microstructural analysis reveals that the stretched composite film features a co-continuous network structure which consists of oriented lamellae bridged by both stretched polymer chains and aligned BNNPs along the stretching direction. The resulting film exhibit a metal-like thermal conductivity as high as 106 W m −1 K −1 and it is believed that the unique network structure has enabled efficient phonon transfer across the film, resulting in superior thermal transporting performance. This work shines a light on the design and scalable manufacturing of high performance functional polymer-based composites for future thermal management applications.

Current Status of Research on the Modification of Thermal Properties of Epoxy Resin-Based Syntactic Foam Insulation Materials

“…In the first section, we mentioned the overall thermal conductivity of composites can be improved by the ultra-high thermal conductivity of BNs, such as building a 3D network [ 88 , 89 , 90 , 91 , 92 , 93 ]. Hou et al [ 94 ] employed this principle to make BNs fibers.…”

Characterizing Biaxially Stretched Polypropylene / Graphene Nanoplatelet Composites

“…Test specimens were cut into 75 mm squares and were clamped using 24 nitrogen-driven pneumatic clamps of the biaxial stretching machine. More detailed configuration of the biaxial stretching machine can be found in (Martin et al, 2005;Zhang et al, 2020). It was found that only unfilled PP and PP/5wt % GNP can be successfully biaxially stretched to SR2.…”

Recent Progress on Fabrication and Performance of Polymer Composites with Highly Thermal Conductivity

“…However, the low thermal conductivity of bulk polymer in range of 0.1-0.5 W m −1 K −1 limits extensive applications which need high heat conduction. [3] It is undeniable that polymers could show higher thermal conductivity with higher crystallite orientation and crystallinity, higher chain alignment, lower entangling, and stronger interchain interactions. [4] Recently, research from Xu et al showed thermal conductivity of polyethylene (PE) films as high as 62 W m −1 K −1 by minimally entangling and maximally aligning the chain.…”