新型氮化硼陶瓷纤维先驱体——含硅聚硼氮烷的合成与表征

以三氯化硼、六甲基二硅氮烷为起始原料, 采用一步法合成了一种新型含硅氮化硼陶瓷纤维先驱体——含硅聚硼氮烷. 该法合成工艺简单, 且合成收率约为87%(质量分数). 采用元素分析、傅立叶红外光谱、核磁共振波谱、热机械分析、动态流变分析等对含硅聚硼氮烷的组成、结构和性能进行了表征. 结果表明, N—B为含硅聚硼氮烷先驱体的骨架结构, 其中, B, N主要以硼氮六环形式存在, 而Si则以Si—CH₃, Si—N形式存在. 该先驱体软化点为110 ℃, 具有优良的成型性, 在190 ℃的N₂气氛中可纺丝得到20～25 μm的有机纤维.

Synthesis and Characterization of Silicon-containing Polyborazine to Boron Nitride Ceramic Fiber

Silicon-containing polyborazine,a novel precursor to boron nitride ceramic fibers,was synthesized via one-pot approach with a yield of about 87%(w%) using boron trichloride(BCl3) and hexamethydisilazane(HMDZ) as the starting materials.The chemical composition,structure and properties of the obtained precursor were investigated using EA,FT-IR,NMR,TMA and dynamic rheological measurement.The results indicate that the backbone of the polymer is N-B linkage in the form of borazine and Si is in the form of Si-CH3...