Enhancement in thermal conductivity and mechanical properties via large-scale fabrication of boron nitride nanosheets

Abstract

In this study, a facial method of fabricating hexagonal boron nitride nanosheet (BNNS) was proposed. Isopropyl alcohol was employed as the solvent to obtain the BNNS via exfoliation of the pristine hexagonal boron nitride. The yield of the exfoliated BNNS with thickness less than 20 nm was as high as 0.17-0.2 mg mL À1 . The BN-and BNNS-filled polyamide 6 (PA6) composites were subsequently prepared by melt blending, and a comparison of thermal conductivity and mechanical properties of the resultant composites were demonstrated. Results indicated that the PA6/BNNS composites showed superior mechanical and thermal conductive properties when compared with that of neat PA6 and PA6/BN composites. At a filler-loading fraction of 40 wt%, thermal conductivity of the PA6/BNNS composite reached 2.496 W mK À1 , which was 21.8% higher than that of PA6/BN composites at the same filler-loading concentration. In addition, the tensile strength of PA6/BNNS composites was invariably higher than that of neat PA6, with a 6.23% increment at a filler concentration of 30 wt%. Based on the results of differential scanning calorimetry, a new crystallization peak (T CC , 2) was observed at higher temperature region for the filler-containing composites and the position of the new peak gradually shifted to higher temperatures with an incremental loading concentration of BN and BNNS.

The Effect of Boron Nitride on the Thermal and Mechanical Properties of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

“…However, the mechanical strength, toughness, and elongation at break (%) values decreased with increasing BN content [ 31 ]. Polyamide 6 (PA6) and BN and exfoliated BN(BNNS) composites were produced by Li et al [ 32 ]. The tensile stress of PA6/BN composites was higher than neat PA6 but for BNNS composites, the greater enhancement was obtained due to the higher aspect ratio BNNS and interaction between the polymer and BNNS [ 32 ].…”

“…Polyamide 6 (PA6) and BN and exfoliated BN(BNNS) composites were produced by Li et al [ 32 ]. The tensile stress of PA6/BN composites was higher than neat PA6 but for BNNS composites, the greater enhancement was obtained due to the higher aspect ratio BNNS and interaction between the polymer and BNNS [ 32 ]. The reinforcement effect of graphene-like BN on the gelatin was investigated by Biscarat et al [ 33 ].…”

In situ Polymerization of Polyamide 6/Boron Nitride Composites to Enhance Thermal Conductivity and Mechanical Properties via Boron Nitride Covalently Grafted Polyamide 6

“…Thus, the h‐BN has been widely used for the modification of polymer materials and especially for the preparation of thermally conductive but electrically insulating materials . Previous studies mainly focused on the exfoliation and the function of h‐BN to elevate TC of polymeric materials . For example, Gu et al reported a method to fabricate epoxy resin/boron nitride (EP/BN) composites through modifying BN.…”

Flexible polyurethane/boron nitride composites with enhanced thermal conductivity

“…Polymer-based thermally conductive composites have received much attention from scientists and researchers due to their low weight, electrical insulation, corrosion resistance, and most importantly, their easy processing. 4,5 Therefore, thermally conductive polymer-based composites are often designed for applications in many fields, such as in light-emitting diodes (LEDs), electronic packaging, thermal interface materials, and integrated circuits. 6,7 Unfortunately, polymers have very low thermal conductivity (generally less than 0.4 W/m·K), 8,9 which is far below the requirements for effective heat dissipation in devices.…”