Abstract
Polymer-derived ceramics(PDCs)is a promising way to prepare ceramic-based electromagnetic functional materials,which can conveniently modulate the composition and dielectric properties of the ceramics.In this paper,SiBCN ceramic matrix composites with excellent high-temperature wave-transparent perfor-mance were prepared through PDC method.Three hyperbranched polyborosilazanes(PBSZs)were pre-pared by adjusting the type of chlorosilane monomers containing different numbers of methyl groups.The carbon element of pyrolytic ceramics was tuned by adjusting the molecular structure of the precur-sor and the pyrolysis temperature.The lower the methyl number and pyrolysis temperature,the lower the dielectric constant of the polymer-derived SiBCN ceramics,which is favorable for electromagnetic wave(EMW)transmittance.The average EMW transmittance of SiBCN-C pyrolyzed from hyperbranched PBSZ using trichlorosilane at 1000 ℃ was 90.56％at room temperature.More excitingly,the excellent wave-transparent performance was also maintained in the temperature range of 100-800 ℃.At the test temperature of 800 ℃,SiBCN-C-1000 still had excellent wave-transparent performance with minimum and average EMW transmittance of 76.13％and 88.96％,respectively.This paper provided a new idea for the preparation of high-temperature wave-transparent SiBCN composite ceramics.
基金项目
National Science Fund for Distinguished Young Scholars(52025034)
National Key Research and Development Program of China(2022YFB3807100/2022YFB3807101)
National Natural science Foundation of China(22005039)
Polymer Electromagnetic Functional Materials Innovation Team of Shaanxi Sanqin Scholars()
NETL
NSTL
万方数据