High thermal conductivity insulating materials with excellent comprehensive properties can be obtained by doping boron nitride nanosheets (BNNSs) into polyimide (PI). To study the microscopic mechanism of composite material decomposition in an actual working environment and the inhibitory effect of BNNS doping on the decomposition process, molecular dynamics simulations were carried out at high temperatures, in intense electric fields, and with various reactive species in plasma based on the reactive force field (ReaxFF). The results showed that the decomposition was mainly caused by hydrogen capture and adsorption, which broke the benzene ring and C-N bond on the PI chains and led to serious damage to the PI structure. The BNNS filling was shown to inhibit the decomposition of the PI matrix at high temperatures and in intense electric fields. Moreover, the BNNS filling also inhibited the material decomposition caused by ·OH and ·NO. The erosive effect of the positive corona on the PI composites was more obvious than that of the negative corona. In this paper, the microscopic dynamic reaction paths of material pyrolysis in various environments were revealed at the atomic level, and it was concluded that BNNS doping could effectively inhibit the decomposition of PI in various environments.
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http://dx.doi.org/10.3390/polym14061169 | DOI Listing |
Adv Sci (Weinh)
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Institute for Engineering Design and Product Development, Research Unit Tribology E307-05, TU Wien, Vienna, 1060, Austria.
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View Article and Find Full Text PDFSmall Methods
January 2025
College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou, 350117, China.
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View Article and Find Full Text PDFJ Phys Chem A
January 2025
School of Environment and Safety Engineering, North University of China, Taiyuan, Shanxi 030051, China.
DNP (3,4-dinitropyrazole) has attracted much interest due to its promising melting characteristics and high detonation performances, such as low melting point, high density, high detonation velocity, and low sensitivity. In this work, first-principles molecular dynamics (MD) simulations were performed to investigate the anisotropic shock response of DNP in conjunction with the multiscale shock technique (MSST). The initial decomposition mechanism was revealed through the evolution of the chemical reaction and product analysis.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Shanghai for Science and Technology, Institute of Energy Material Science, Shanghai 200093, Shanghai, CHINA.
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View Article and Find Full Text PDFInorg Chem
January 2025
School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
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