课题组最新论文“Soluble and Meltable Hyperbranched Polyborosilazanes toward High-Temperature Stable SiBCN Ceramics”在ACS Appl. Mater. Interfaces (2015, 7, 6733)期刊上发表。

网页链接http://pubs.acs.org/doi/abs/10.1021/am509129a

论文采用超支化拓扑结构设计，首次实现了聚硼硅氮烷耐高温陶瓷前驱体的可溶、可熔，主要特色在于：1）根据所采用单体的特点，因势利导，利用A₂+B₆的设计，使得硼原子分布在主链上，且含量很容易达到一个高的水平，典型热解陶瓷元素含量为Si₁B_0.2C_1.2N_0.4；2）利用三烷基硼烷的转胺反应，在无催化剂状态下，得到了树状单元为更为稳定的二烷基胺基硼的超支化聚合物，乙烯基、硅氢键等活性基团得以保留，热解产率高，所得SiBCN复相陶瓷在1600度仍保持无定形状态；3）准固相反应、无需催化剂，具有规模合成的潜力，目前已申报中国发明专利并获得受理，并在德国陶瓷学会2015年会上报告，国际上聚合物转化陶瓷此领域多个顶尖研究组，如法国Montpellier大学Miele教授、德国Darmstadt工业大学Ionescu教授等当场表达了合作研究的意愿。

Abstract: High-temperature stable siliconborocarbonitride (SiBCN) ceramics produced from single-source preceramic polymers have received increased attention in the last two decades. In this contribution, soluble and meltable polyborosilazanes with hyperbranched topology (hb-PBSZ) were synthesized via a convenient solvent-free, catalyst-free and one-pot A2+B6 strategy—an aminolysis reaction of the A2 monomer of dichloromethylsilane and the B6 monomer of tris(dichloromethylsilylethyl)borane in the presence of hexamethyldisilazane. The amine transition reaction between the intermediates of dichlorotetramethyldisilazane and tri(trimethylsilylmethylchlorosilylethyl)borane led to the formation of dendritic units of aminedialkylborons rather than trialkylborons. The cross-linked hb-PBSZ precursors exhibited a ceramic yield higher 80%. The resultant SiBCN ceramics with a boron atomic composition of 6.0–8.5% and a representative formula of Si1B0.2C1.2N0.4O0.08 showed high-temperature stability and retained their amorphous structure up to 1600 °C. These hyperbranched polyborosilazanes with soluble and meltable characteristics provide a new perspective for the design of preceramic polymers possessing advantages for high-temperature stable polymer-derived ceramics with complex structures/shapes.