課題組最新論文在ACS Appl. Mater. Interfaces上發(fā)表
課題組最新論文“Soluble and Meltable Hyperbranched Polyborosilazanes toward High-Temperature Stable SiBCN Ceramics”在ACS Appl. Mater. Interfaces (2015, 7, 6733)期刊上發(fā)表。
網(wǎng)頁鏈接http://pubs.acs.org/doi/abs/10.1021/am509129a
論文采用超支化拓撲結(jié)構(gòu)設計，首次實現(xiàn)了聚硼硅氮烷耐高溫陶瓷前驅(qū)體的可溶、可熔，主要特色在于：1）根據(jù)所采用單體的特點，因勢利導，利用A2+B6的設計，使得硼原子分布在主鏈上，且含量很容易達到一個高的水平，典型熱解陶瓷元素含量為Si1B0.2C1.2N0.4；2）利用三烷基硼烷的轉(zhuǎn)胺反應，在無催化劑狀態(tài)下，得到了樹狀單元為更為穩(wěn)定的二烷基胺基硼的超支化聚合物，乙烯基、硅氫鍵等活性基團得以保留，熱解產(chǎn)率高，所得SiBCN復相陶瓷在1600度仍保持無定形狀態(tài)；3）準固相反應、無需催化劑，具有規(guī)模合成的潛力，目前已申報中國發(fā)明專利并獲得受理，并在德國陶瓷學會2015年會上報告，國際上聚合物轉(zhuǎn)化陶瓷此領域多個頂尖研究組，如法國Montpellier大學Miele教授、德國Darmstadt工業(yè)大學Ionescu教授等當場表達了合作研究的意愿。
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.