新型碳化硅陶瓷前驱体聚（甲基硅烷-碳硅烷）的合成与表征

Synthesis and characterization of a new poly(methylsilane-carbosilane) for SiC precursor

摘要

碳化硅陶瓷基复合材料（SiC-CMC）是一种轻质高强的耐高温热结构材料，已广泛应用于航空航天等高新技术领域。碳化硅陶瓷前驱体是采用前驱体浸渍裂解工艺制备这类复合材料的基础原材料，但高昂成本限制了其商业化批量应用，发展新型的低成本碳化硅陶瓷前驱体对SiC-CMC的发展和规模应用具有重要意义。本工作以二氯甲基甲基硅烷（Cl₂CHSiMeH₂）为单体、氯甲基甲基硅烷（ClCH₂SiMeH₂）为封端剂，通过Wurtz偶联反应合成新型碳化硅陶瓷前驱体聚合物（PMSCS）。由于单体中部分Si―H键在聚合过程中也参与反应，PMSCS是一种分子结构主链由C―C和Si―C键组成的支化结构聚合物，其储存稳定性和溶解性良好，1000 ℃陶瓷产率达74%（质量分数）。与目前应用最广的Yajima法聚碳硅烷相比，PMSCS的合成更为简便，无需高温重排步骤，熔点更低且陶瓷产率更高；与超支化液态聚碳硅烷的制备相比，PMSCS不涉及使用昂贵的还原剂氢化铝锂，因此，其作为低成本碳化硅陶瓷前驱体具有良好的应用前景。

Abstract

Silicon carbide ceramic matrix composites (SiC-CMC) are lightweight，high-strength and high-temperature resistant thermal structural materials，which have been widely applied in high-tech fields such as aerospace. Preceramic polymers are key materials for the fabrication of such composites via the process of precursor infiltration and pyrolysis. However，the high cost of the materials has prevented their widespread use. Developing new silicon carbide ceramic precursors and reducing their preparation costs are of great significance for the advancement and application of SiC-CMC. In this work，a new silicon carbide ceramic precursor polymer，PMSCS，was synthesized via the Wurtz coupling reaction using dichloromethylmethylsilane (Cl₂CHSiMeH₂) and chloromethylmethylsilane (ClCH₂SiMeH₂) as the monomer and end-capping agent，respectively. Owing to the participation of reactive Si―H bonds in the monomer during polymerization，PMSCS is a branched polymer with a main chain consists of C―C bonds along with Si―C bonds，which exhibits good solubility and storage stability，with a ceramic yield of 74% (mass fraction) upon pyrolysis at 1000 ℃ under inert atmosphere. Compared with the most widely used Yajima method polycarbosilane，PMSCS offers a higher ceramic yield，and its synthesis is simpler，eliminating the need for a high-temperature rearrangement step. Additionally，the synthesis of PMSCS does not require expensive lithium aluminum hydride as a reducing agent，which is essential for the preparation of hyperbranched liquid polycarbosilane. Therefore，PMSCS shows promising potential as a cost effective silicon carbide ceramic precursor.

关键词

碳化硅陶瓷 / 聚合物前驱体 / 改性聚甲基硅烷

Key words

SiC ceramic / polymer precursor / modified polymethylsilane

参考文献

[1] Ichikawa H. Polymer—derived ceramic fibers[J].Annual Review of Materials Research，2016，46：335-356.

[2] Ackley B J，Martin K L，Key T S，et al. Advances in the synthesis of preceramic polymers for the formation of silicon—based and ultrahigh—temperature non—oxide ceramics[J].Chemical Reviews，2023，123（8）：4188-4236.

[3] Zhou Y，Lu K. Polymer—derived high—temperature nonoxide materials：a review[J].Advanced Engineering Materials，2023，25（9）：2200967.

[4] Li X H，Ye C，Chen J J，et al. Synthesis and characterization of Al and Ti Co—doped polycarbosilane for Si（Al，Ti）CO and Si（Al，Ti）C ceramic fibers[J].Ceramics International，2026，52（7）：9419-9434.

[5] 卢玲，宋永才 . SiC纤维先驱体：聚碳硅烷的催化合成[J].高技术通讯，1995，5（3）：36-39.

[6] Lu L，Song Y C. Catalytic aynthesis of the precursor of SiC fiber：polycarbosilane[J].High Technology Letters，1995，5（3）：36-39.

[7] 顾喜双，宋永才 . 热固化聚碳硅烷的合成及性能[J].有机硅材料，2015，29（6）：462-468.

[8] Gu X S，Song Y C. Preparation and properties of thermocurable polycarbosilane[J].Silicone Material，2015，29（6）：462-468.

[9] 李永强，宋永才 . 高软化点聚碳硅烷的合成及可纺性[J].高等学校化学学报，2014，35（10）：2272-2280.

[10] Li Y Q，Song Y C. Synthesis and spinnability of the high softening—point polycarbosilane[J].Chemical Journal of Chinese Universities，2014，35（10）：2272-2280.

[11] 王国栋，宋永才 . SiC基复合材料先驱体聚合物研究进展[J].有机硅材料，2014，28（2）：130-135.

[12] Wang G D，Song Y C. Research progress on precursors to prepare SiC ceramic matrix composites[J].Silicone Material，2014，28（2）：130-135.

[13] 李永明，杨潇淦，徐彩虹，等 . 一种聚碳硅烷的催化重排制备方法：CN201410301685.3[P].2016-01-27.

[14] 曹适意，王军，王浩 . 液态超支化聚碳硅烷的合成及应用进展[J].化工进展，2012，31（8）：1745-1750.

[15] Cao S Y，Wang J，Wang H. Advance in the synthesis and application of liquid hyperbranched polycarbosilane[J].Chemical Industry and Engineering Progress，2012，31（8）：1745-1750.

[16] 荆楚凡，缑新岳，张宗波，等 . 液态SiC陶瓷前驱体分子结构与固化热解行为[J].硅酸盐学报，2024，52（9）：2780-2788.

[17] Jing C F，Gou X Y，Zhang Z B，et al. Molecular structure of liquid SiC ceramic precursors and their curing and pyrolysis behavior[J].Journal of the Chinese Ceramic Society，2024，52（9）：2780-2788.

[18] He L J，Zhang Z B，Yang X G，et al. Liquid polycarbosilanes：synthesis and evaluation as precursors for SiC ceramic[J].Polymer International，2015，64（8）：979-985.

[19] 郭洪亮，王小宙 . 液态聚碳硅烷的一步超声缩合制备及其表征[J].硅酸盐学报，2024，52（9）：2800-2805.

[20] Guo H L，Wang X Z. One—step ultrasonic condensation preparation and characterization of liquid polycarbosilane[J].Journal of the Chinese Ceramic Society，2024，52（9）：2800-2805.

[21] Laine R M，Babonneau F. Preceramic polymer routes to silicon carbide[J].Chemistry of Materials，1993，5（3）：260-279.

[22] 刘琳 . 改性聚甲基硅烷系列SiC陶瓷先驱体的研究[D].长沙：国防科学技术大学，2008.

[23] Liu L. Study on the preceramic polymer for SiC ceramic—modified polymethylsilane system[D]. Changsha：National University of Defense Technology，2008.

[24] 邢欣，李效东，郭爱青，等 . 聚甲基硅烷稳定性的研究[J].硅酸盐学报，2004，32（4）：402-406.

[25] Xing X，Li X D，Guo A Q，et al. Study on stability of polymethylsilane[J].Journal of the Chinese Ceramic Society，2004，32（4）：402-406.

[26] 高波，王浩，王小宙 . 聚甲基硅烷的研究进展[J].化工进展，2011，30（8）：1772-1777.

[27] Gao B，Wang H，Wang X Z. Research progress of polymethylsilane[J].Chemical Industry and Engineering Progress，2011，30（8）：1772-1777.

[28] 邢欣，刘琳，苟燕子，等 . 碳化硅陶瓷先驱体聚甲基硅烷的研究进展[J].硅酸盐学报，2009，37（5）：898-904.

[29] Xing X，Liu L，Gou Y Z，et al. Research progress of polymethylsilane in precursor of silicon carbide ceramics[J].Journal of the Chinese Ceramic Society，2009，37（5）：898-904.

[30] 廖明东 . 改性聚甲基硅烷制备C/C—SiC、C/C—ZrC—SiC及性能研究[D].长沙：中南大学，2024.

[31] Liao M D. Study on the preparation and properties of C/C—SiC and C/C—ZrC—SiC fabricated by the modified polymethylsilane[D]. Changsha：Central South University，2024.

[32] 王新良 . 改性聚甲基硅烷的合成及其用于碳化硅陶瓷前驱体的研究[D].北京：中国科学院大学，2019.

[33] Wang X L. Synthesis of modified polymethylsilane and its application as precursor of silicon carbide ceramics[D]. Beijing：University of Chinese Academy of Sciences，2019.

[34] Zhang Z F，Babonneau F，Laine R M，et al. Poly（methylsilane）：a high ceramic yield precursor to silicon carbide[J].Journal of the American Ceramic Society，1991，74（3）：670-673.

[35] Mu Y，Harrod J F，Laine R M. Some further observations on polymethylsilane as a precursor for silicon carbide[J].Applied Organometallic Chemistry，1994，8（2）：95-100.

[36] Gozzi M F，Gonĉalves M D C，Yoshida I V P. Near—stoichiometric silicon carbide from a poly（methylsilylene）/tetra—allylsilane mixture[J].Journal of Materials Science，1999，34（1）：155-159.

[37] Gozzi M F，Yoshida I V P. Structural evolution of a poly（methylsilane）/tetra—allylsilane mixture into silicon carbide[J].European Polymer Journal，1997，33（8）：1301-1306.

[38] Yajima S，Hasegawa Y，Hayashi J，et al. Synthesis of continuous silicon carbide fibre with high tensile strength and high Young’s modulus：part 1 synthesis of polycarbosilane as precursor[J].Journal of Materials Science，1978，13（12）：2569-2576.

[39] Huang T H，Yu Z J，He X M，et al. One—pot synthesis and characterization of a new，branched polycarbosilane bearing allyl groups[J].Chinese Chemical Letters，2007，18（6）：754-757.

[40] Schmidt W R，Interrante L V，Doremus R H，et al. Pyrolysis chemistry of an organometallic precursor to silicon carbide[J].Chemistry of Materials，1991，3（2）：257-267.

[41] Boury B，Bryson N，Soula G. Stoichiometric silicon carbide from borate—catalyzed polymethylsilane—polyvinylsilane formulations[J].Applied Organometallic Chemistry，1999，13（6）：419-430.