SiBN陶瓷纤维的脱碳工艺研究  

Decarburization research of SiBN ceramic fibers

作　　者：黄先华[1] 刘勇[1] 张晨宇[1] 常雪峰[1] 崔永杰[1] 彭帅[1] 韩克清[1] 余木火[1] 

机构地区：[1]东华大学材料科学与工程学院纤维材料改性国家重点实验室高性能纤维与制品教育部重点实验室,上海201620

出　　处：《合成纤维工业》2017年第2期1-5,共5页China Synthetic Fiber Industry

基　　金：上海市自然科学基金项目(15ZR1400400);上海市科委重点项目(14JC1400100)

摘　　要：以三氯化硼、六甲基二硅氮烷、三氯硅烷和甲胺为原料,采用多步法合成、聚合得到可纺性良好的聚硼氮硅烷(PBSZ)前驱体,通过熔融纺丝得到前驱体纤维,再经热化学交联得到不熔化纤维;在氨气/氮气(NH_3/N_2)气氛下进行热解脱碳(C)处理制备了硅硼氮(SiBN)陶瓷纤维;研究了NH_3/N_2体积比、气体流量、升温速率、保温时间以及热解温度等对SiBN纤维中C含量的影响,分析了PBSZ的脱C机理。结果表明:较优的热解工艺是NH_3/N_2体积比为3∶1,升温速率为0.5℃/min,600℃和1 000℃分别保温3 h,气体流量为100 m L/min,可制备C质量分数小于0.1%的Si BN陶瓷纤维;NH3对脱C具有积极作用,在热交联反应、自由基反应和脱氢偶合反应的综合作用下,C主要以甲胺和甲烷的形式脱除。A polyborosilazane （PBSZ） precursor with good spinnability was synthsized by using boron trichloride, hexamethyld- isilazane, trichlorosilane and methylamine as raw material via multi-stage polymerization, from which the precursor fiber was ob- tained by melt spinning process and was produced into a non-molten fiber through thermochemical crosslinking. A silicon boron nitrogen （SiBN） ceramic fiber was prepared from the non-molten fiber by pyrolysis decarburization （C） treatment under ammo- nia/nitrogen（ NH3/N2 ） atmosphere. The effects of NH3/N： volume ratio, gas flow, heating rate, preservation time and pyrolysis temperature on C content of SiBN fiber were studied. The decarburization mechanism of PBSZ was analyzed. The results showed that the SiBN ceramic fiber containing C below 0. 1% by mass fraction could be produced under the optimized pyrolysis conditions as followed： NH3/N2 volume ratio 3 ： 1, heating rate 0.5 ℃/min, preservation time 3 h respectively at 600 ℃ and 1 000℃, gas flow 100 mL/min; NH3 contributed a positive effect on decarburization, and C was removed in the forms of methylamine and methane by the cooperation of thermocrosslinking reaction, free radical reaction and dehydrogenation coupling agent.

关 键 词：硅硼氮 陶瓷纤维 聚硼氮硅烷 热解 脱碳 

分 类 号：TQ343.41[化学工程—化纤工业]