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(yè)鏈接http://pubs.acs.org/doi/abs/10.1021/am509129a
論文采用超支化拓?fù)浣Y(jié)構(gòu)設(shè)計(jì)，首次實(shí)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(diǎn)，因勢(shì)利導(dǎo)，利用A2+B6的設(shè)計(jì)，使得硼原子分布在主鏈上，且含量很容易達(dá)到一個(gè)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(yīng)，在無(wú)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(tuán)得以保留，熱解產(chǎn)率高，所得SiBCN復(fù)相陶瓷在1600度仍保持無(wú)定形狀態(tài)；3）準(zhǔn)固相反應(yīng)、無(wú)需催化劑，具有規(guī)模合成的潛力，目前已申報(bào)中國(guó)發(fā)明專利并獲得受理，并在德國(guó)陶瓷學(xué)會(huì)2015年會(huì)上報(bào)告，國(guó)際上聚合物轉(zhuǎn)化陶瓷此領(lǐng)域多個(gè)頂尖研究組，如法國(guó)Montpellier大學(xué)Miele教授、德國(guó)Darmstadt工業(yè)大學(xué)Ionescu教授等當(dāng)場(chǎng)表達(dá)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.