scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Highly anisotropic thermal and electrical conductivities of nylon composite papers with the integration of strength and toughness

19 Oct 2021-Journal of Materials Chemistry (The Royal Society of Chemistry)-Vol. 9, Iss: 40, pp 22982-22993
TL;DR: In this paper, the in-plane thermal and electrical conductivities of nylon composites were improved by using a facile method involving vacuum-assisted filtration and compression molding processes.
Abstract: The mechanical properties of thermally conductive composites are the key to realize their applications. Strength of materials is of significance, furthermore the toughness of materials also should attract more concern. Actually, few researchers have reported the simultaneous improvement of strength and toughness of anisotropic thermally and electrically conductive composites. Therefore, this study aims to obviously improve the in-plane thermal and electrical conductivities of nylon composites, which display superior tensile strength and toughness, compared to other thermally conductive composites. The nylon composite papers, prepared through a facile method involving vacuum-assisted filtration and compression molding processes, present a laminate structure and compact graphene nanoplatelet (GNP) stacks inside composites. On account of the special structure, the nylon composite papers show a super-high in-plane thermal conductivity of 16.0 W m−1 K−1 and electrical conductivity of 18.0 S cm−1 at a filler loading of 14.6 wt%. Surprisingly, the composite papers still exhibit a high strength of 48.3 MPa, which is comparable to that of a pure nylon film. In addition, the elongation at break of the composite paper with 14.6 wt% GNPs is as high as 34.2%, ultimately endowing the composite papers with a good toughness of 13.15 MJ m−3. The nylon composite papers successfully achieve the integration of excellent thermal and electrical conductivities, and superior strength and toughness, showing huge application values in the field of intelligent electronic device.
Citations
More filters
Journal ArticleDOI
TL;DR: In this article , a polydimethylsiloxane/boron nitride nanosheets (PDMS/BNNS) foam scaffold was prepared by the sugar-templated method, and the corresponding PDMS and BNNS composites were manufactured with vacuum-assisted PDMS impregnation and curing.
Abstract: With the electronic device advancing to miniaturization, higher integration and flexibility, flexible polymer composites with high thermal conductivity are desirable for efficient removal of accumulated heat to maintain normal operation of electronics. In this work, a polydimethylsiloxane/boron nitride nanosheets (PDMS/BNNS) foam scaffold was prepared by the sugar-templated method, and the corresponding PDMS/BNNS composites were manufactured with vacuum-assisted PDMS impregnation and curing. The PDMS/BNNS composites exhibit a three-dimensional (3D) BNNS interconnected network with curved BNNS pathways due to the intensive compression during hot-pressing curing, providing thermally conductive network and corresponding prestrains for deformable application. The PDMS/BNNS composites finally can achieve a high thermal conductivity of 7.55 W m−1 K−1 in the in-plane direction and 1.12 W m−1 K−1 in the through-plane direction with 25 vol% BNNS, which represent 153% and 78% increases over the composites prepared by randomly mixing method, respectively. In addition, the composite still maintains superior heat dissipation property under repeated stretching and bending conditions, which indicates a broad and bright application for thermal management in flexible electronic devices.

15 citations

Journal ArticleDOI
TL;DR: In this paper , surface-induced polyamide acid (PAA) polymerization on boron nitride nanosheets (BNNSs) was firstly achieved, and then the BNNS@PAA was introduced into the polymerization system of polyimide (PI).
Abstract: With the rapid development of electrical equipment and integrated circuits, packaging materials with high heat dissipation capability are in great demand. Reducing the interfacial thermal resistance is still a great challenge in polymeric composites. Herein, surface-induced polyamide acid (PAA) polymerization on boron nitride nanosheets (BNNSs) was firstly achieved, and then the BNNS@PAA was introduced into the polymerization system of polyimide (PI). The dependence of microstructures and performances of the composites on imidization degree of BNNS@PAA was systematically investigated. The results show that there is an appropriate imidization temperature (120 °C), at which the composite with only 10 wt% BNNS@PAA exhibits high thermal conductivity (2.11 W/m·K), excellent mechanical properties (with tensile strength of 97.2 MPa and elongation at break of 19.8%), and good dielectric properties (with a discharged energy density of 3.67 J/cm 3 and a charge-discharge efficiency of 87.4% at the field of 300 MV/m).

3 citations

Journal ArticleDOI
TL;DR: In this article , a series of multilayered boron nitride/graphene nanoplate (BN/GNP) composites by virtue of a sequentially layered assembly strategy is realized through unidirectional freezing drying followed by alternative compression molding.

1 citations

References
More filters
Journal ArticleDOI
01 Mar 2010-Carbon
TL;DR: In this paper, a dielectric spectroscopy of short carbon fiber/silica composite in the frequency range from 8.2 to 12.4 GHz at temperatures between 30 and 600°C has been performed.

1,540 citations

Journal ArticleDOI
TL;DR: Chemical graphitized r-GOs, as the thinnest and lightest material in the carbon family, exhibit high-efficiency electromagnetic interference shielding at elevated temperature, attributed to the cooperation of dipole polarization and hopping conductivity.
Abstract: Chemical graphitized r-GOs, as the thinnest and lightest material in the carbon family, exhibit high-efficiency electromagnetic interference (EMI) shielding at elevated temperature, attributed to the cooperation of dipole polarization and hopping conductivity. The r-GO composites show different temperature-dependent imaginary permittivities and EMI shielding performances with changing mass ratio.

1,358 citations

Journal ArticleDOI
01 Mar 2009-Carbon
TL;DR: In this paper, composites based on graphene-based sheets have been fabricated by incorporating solution-processable functionalized graphene into an epoxy matrix, and their electromagnetic interference (EMI) shielding studies were studied.

1,175 citations

Journal ArticleDOI
TL;DR: The results indicate that single-walled carbon nanotube-polymer composites can be used as effective lightweight EMI shielding materials and are found to correlate with the dc conductivity.
Abstract: Single-walled carbon nanotube (SWNT)−polymer composites have been fabricated to evaluate the electromagnetic interference (EMI) shielding effectiveness (SE) of SWNTs. Our results indicate that SWNTs can be used as effective lightweight EMI shielding materials. Composites with greater than 20 dB shielding efficiency were obtained easily. EMI SE was tested in the frequency range of 10 MHz to 1.5 GHz, and the highest EMI shielding efficiency (SE) was obtained for 15 wt % SWNT, reaching 49 dB at 10 MHz and exhibiting 15−20 dB in the 500 MHz to 1.5 GHz range. The EMI SE was found to correlate with the dc conductivity, and this frequency range is found to be dominated by reflection. The effects of SWNT wall defects and aspect ratio on the EMI SE were also studied.

1,148 citations

Journal ArticleDOI
TL;DR: In this paper, a graphitization of graphite-like graphene oxide (GO) films was used to produce ultrathin thermal conducting materials (TCMs) with the combination of high thermal conductivity and excellent electromagnetic interface (EMI) shielding performance.
Abstract: As the portable device hardware has been increasing at a noticeable rate, ultrathin thermal conducting materials (TCMs) with the combination of high thermal conductivity and excellent electromagnetic interface (EMI) shielding performance, which are used to efficiently dissipate heat and minimize EMI problems generated from electronic components (such as high speed processors), are urgently needed. In this work, graphene oxide (GO) films are fabricated by direct evaporation of GO suspension under mild heating, and ultrathin graphite-like graphene films are produced by graphitizing GO films. Further investigation demonstrates that the resulting graphene film with only approximate to 8.4 mu m in thickness not only possesses excellent EMI shielding effectiveness of approximate to 20 dB and high in-plane thermal conductivity of approximate to 1100 W m(-1) K-1, but also shows excellent mechanical flexibility and structure integrity during bending, indicating that the graphitization of GO film could be considered as a new alternative way to produce excellent TCMs with efficient EMI shielding.

723 citations