Lightweight Porous Polystyrene with High Thermal Conductivity by Constructing 3D Interconnected Network of Boron Nitride Nanosheets

Abstract

A composite foam consisting of foamed cross-linking polystyrene (c-PS) and boron nitride nanosheets (BNNSs) was synthesized, which shows a higher thermal conductivity (TC) than the corresponding solid counterparts. The BNNSs fillers are found to be aligned along the cell wall as a result of the biaxial stress field from cell expansion during the formation of 3-dimensional interconnectivity in the foams, resulting in an enhanced TC of 1.28 W/m K, near 2 and 4 times those of its solid counterpart and pure c-PS, respectively. It is found that the foaming-assisted formation of the filler network is an efficient strategy to improve the TC at low filler loadings in the composites. Furthermore, the composite foams exhibit low-density, rather low dielectric constants and dissipation factors at wide frequency and temperature ranges. The present work provides a novel approach to designing and preparing lightweight heat conductive polymers with low filler loadings as low-density heat management materials for potential applications in aeronautics and aerospace components.

Preparation of poly glycidyl methacrylate (PGMA) chain-grafted boron nitride/epoxy composites and their thermal conductivity properties

“…Constructing thermal conduction channels and reducing interfacial thermal resistance are effective ways to improve the thermal conductivity of epoxy composites. 28 Fig. 9 shows the thermal conductivity of the composite materials.…”

Voltage-Stabilizer-Grafted SiO2 Increases the Breakdown Voltage of the Cycloaliphatic Epoxy Resin

“…According to the mechanism of the potential barrier model, the difference in interface characteristics and the content of nanofillers leads to a decrease of the dielectric constant, and its changing trend model is similar to the reported polymer-based nanocomposites in literature studies. 51 − 53 …”

Anchoring modified polystyrene to boron nitride nanosheets as highly thermal conductive composites for heat dissipation

“…[27][28][29] Despite significant success progress in boosting the compatibility of BN, the adhesion improvement between BN fillers and polymer matrixes is still limited, mostly due to the poor polarity of the inert matrixes. [30] In this study, BN nanosheets were pre-treated in NaOH solution using a sonication technique to simultaneously achieve their exfoliation and hydroxylation. The intrinsic TC of exfoliated BN (BN-OH) is higher than that of pristine BN due to the decrease of the phonon-phonon scattering in the longitudinal direction.…”