含锆聚硼硅氮烷的合成与表征  

Synthesis and Characterization of Novel Zr-Modified Polyborosilazane

作　　者：龙鑫[1] 邵长伟[1] 朱旖华 王浩[1] 

机构地区：[1]国防科技大学新型陶瓷纤维及其复合材料重点实验室 [2]92730部队装备部老化管理办公室

出　　处：《稀有金属材料与工程》2016年第S1期131-136,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51203184);国家高技术研究发展计划("863"项目)(2012AA03A210);湖南省高校科技创新团队支持计划;国防科技大学创新群体资助

摘　　要：通过二氯二茂化锆(Zr(Cp)_2Cl_2)与液态聚硼硅氮烷(LPBS)反应制备了含锆聚硼硅氮烷(PBS-Zr),随着Zr(Cp)2Cl2投料比的增加,PBS-Zr的分子量明显增大,且出现了高分子量部分,陶瓷产率达到56%(质量分数)。红外光谱显示了含锆聚硼硅氮烷中N-H、Si-H等活性键明显减少。XPS谱图显示了PBS-Zr与Zr(Cp)_2Cl_2中Zr原子化学结构的差异。通过29SiMASNMR分析表明,陶瓷产物中Si元素主要以SiN3C、SiN42种结构存在。XRD分析显示,陶瓷产物在1200℃以下保持无定形状态,1600℃出现了Zr_2CN和Si3_N_4等微晶结构,但继续升温到1800℃,这2种微晶都发生了分解,转化为ZrB_2和SiC结晶相。Zr-modified polyborosilazanes(PBS-Zr) was synthesized via one-pot reaction between Zr(Cp)_2Cl_2 and liquid polyborosilazane of different mass ratios. The structure and properties of PBS-Zr were studied using MAS NMR, FTIR, GPC and TG. The composition and microstructure of Si BNC-Zr ceramics derived from the precursor were investigated by MAS NMR and XRD. With the increasing of addition of Zr(Cp)_2Cl_2, the molecular mass of PBS-Zr obviously increases and even polymers of very high molecular mass appeares according to the results of GPC. Meantime, the amount of N-H and Si-H of the preceramic polymer PBS-Zr reduces apparently as shown in FT-IR spectra. Therefore, the amount of Zr(Cp)_2Cl_2 is limited to 20 wt% and even less in order to avoid over-crosslinking. The ceramic yield of PBS-Zr is as high as 56 wt% at 1000 oC under nitrogen. Elucidated by 29 Si MAS NMR spectra, Si element mainly exists as SiN_3C and Si N_4 in the Si BNC-Zr ceramics derived from the precursor. The ceramics stay as amorphous phase at 1200 oC. Nanocrystallines of Zr_2 CN and Si_3N_4 appear at 1600 oC, which changes to ZrB_2 and Si C nanocrystallines at 1800 oC according to the analysis of XRD spectra.

关 键 词：聚硼硅氮烷 锆 陶瓷先驱体 超高温陶瓷 SiBNC 

分 类 号：TQ174.1[化学工程—陶瓷工业]