TY - JOUR
T1 - Highly thermally conductive 3D BN/MWCNTs/C spatial network composites with improved electrically insulating and flame retardancy prepared by biological template assisted method
AU - Pan, Duo
AU - Luo, Shilu
AU - Feng, Yao
AU - Zhang, Xiaodong
AU - Su, Fengmei
AU - Liu, Hu
AU - Liu, Chuntai
AU - Mai, Xianmin
AU - Naik, Nithesh
AU - Guo, Zhanhu
N1 - Funding Information:
The morphologies of the samples obtained in the preparation process were identified by SEM. Fig. 4a and b shows the SEM images of the RP template. The pollen grains consist of fine hollow ellipsoids with the particle size is about 5 ? 10 mm and each ellipse is surrounded by reticular shell structure. The reticular shells composed of open pore networks (with diameter about 500?550 nm) provide a large and connective surface. In Fig. 4c and d, in contrast to the original BN, the diameter of the m-BN transparent flakes obtained after the BA ball milling modification treatment has been reduced from 10 to 2 ?m [42]. The special pore structure and abundant chemical bonds on the surface of RP make c-MWCNTs uniformly adsorbed on its surface (Fig. 4e). Also, the unique reticular shells structure of RP also provides template support for further chemical crosslinking of m-BN on the surface of c-MWCNTs (Fig. 4f). To illustrate the framework template role of RP in this study, the SEM images of m-BN/c-MWCNTs/PVDF (without RP) and m-BN/c-MWCNTs/RP/PVDF (with RP) are shown in Fig. 4g and h. The corresponding SEM images after high temperature carbonization treatment at 550 ?C are shown in Fig. 4i and 4j?l. The m-BN/c-MWCNTs/CPVDF (Fig. 4i) obtained by carbonization of m-BN/c-MWCNTs/PVDF is composed of m-BN stacks connected by c-MWCNTs, but the MWCNTs do not form continuous and effective pathways. While the m-BN/c-MWCNTs/C (Fig. 4j-l) obtained by carbonization of m-BN/c-MWCNTs/RP/PVDF by removing the templates is composed of a continuous structure similar to a honeycomb (Fig. 4j), with each honeycomb having a diameter of about 10 ?m (Fig. 4k) and the honeycomb wall is a continuous network composed of c-MWCNTs connected to m-BN (Fig. 4l). This structure not only enhances the strength of the honeycomb reinforcement, but also facilitates the formation of 3D interconnected thermal conductive networks for the polymer-based composites [43].We acknowledge for the financial support from National Natural Science Foundation of China (21704096, 51703217) and the China Postdoctoral Science Foundation (Grant no. 2019M662526).
Funding Information:
We acknowledge for the financial support from National Natural Science Foundation of China ( 21704096 , 51703217 ) and the China Postdoctoral Science Foundation (Grant no. 2019M662526 ).
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/10/1
Y1 - 2021/10/1
N2 - Boron nitride/multiwalled carbon nanotubes/carbon (BN/MWCNTs/C) networks were prepared via a rape pollen (RP) biological template assisted strategy. The highly thermally conductive epoxy resin (EP) composites were prepared by impregnating EP into the 3D BN/MWCNTs/C networks. Fourier transform infrared spectra and X-ray photoelectron spectroscopy analyses indicated that the successful modification of BN (m-BN) and the interaction between RP, carboxyl functionalized MWCNTs (c-MWCNTs) and m-BN. Scanning electron microscopy images clearly present the network morphology constructed by MWCNTs connected to m-BN. Thermogravimetric analyzer curves determine the mass concentration of m-BN in EP-based composites. The thermal conductivity (K) reached 1.84 W/(m·K) in the composites at a BN content of 21.3 wt%, displaying a significant enhancement of 868% compared with pure EP. The enhanced K is attributed to the effective connection of BN by the MWCNTs covered on the surface of RP. Meanwhile, the composites exhibit a tensile strength of 39.2 MPa, electrically insulating with a volume electrical resistivity about 9.17 × 1010 Ω cm and good flame retardancy.
AB - Boron nitride/multiwalled carbon nanotubes/carbon (BN/MWCNTs/C) networks were prepared via a rape pollen (RP) biological template assisted strategy. The highly thermally conductive epoxy resin (EP) composites were prepared by impregnating EP into the 3D BN/MWCNTs/C networks. Fourier transform infrared spectra and X-ray photoelectron spectroscopy analyses indicated that the successful modification of BN (m-BN) and the interaction between RP, carboxyl functionalized MWCNTs (c-MWCNTs) and m-BN. Scanning electron microscopy images clearly present the network morphology constructed by MWCNTs connected to m-BN. Thermogravimetric analyzer curves determine the mass concentration of m-BN in EP-based composites. The thermal conductivity (K) reached 1.84 W/(m·K) in the composites at a BN content of 21.3 wt%, displaying a significant enhancement of 868% compared with pure EP. The enhanced K is attributed to the effective connection of BN by the MWCNTs covered on the surface of RP. Meanwhile, the composites exhibit a tensile strength of 39.2 MPa, electrically insulating with a volume electrical resistivity about 9.17 × 1010 Ω cm and good flame retardancy.
UR - https://www.scopus.com/pages/publications/85107633358
UR - https://www.scopus.com/pages/publications/85107633358#tab=citedBy
U2 - 10.1016/j.compositesb.2021.109039
DO - 10.1016/j.compositesb.2021.109039
M3 - Article
AN - SCOPUS:85107633358
SN - 1359-8368
VL - 222
JO - Composites Part B: Engineering
JF - Composites Part B: Engineering
M1 - 109039
ER -