细直径聚硅氮烷纤维的碘蒸气不熔化机理  

Iodine vapor curing mechanism of fine diameter polysilazane fibers

作　　者：鲍之豪 李晓鸿 李金霞 罗小雨 张潇[1] 陈浩[1] 陈建军[1] BAO Zhihao;LI Xiaohong;LI Jinxia;LUO Xiaoyu;ZHANG Xiao;CHEN Hao;CHEN Jianjun(School of Materials Science&Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学材料科学与工程学院,杭州310018

出　　处：《浙江理工大学学报（自然科学版）》2023年第2期198-205,共8页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：国家自然科学基金项目(51572243;51872262)。

摘　　要：为探究聚硅氮烷纤维的碘蒸气不熔化机理,以甲基二氯硅烷和二甲基二氯硅烷为原料,采用先驱体转化法制备了直径为6.5μm的连续细直径聚硅氮烷(Polysilazane,PSZ)纤维,采用碘蒸气不熔化来制备PSZ交联纤维。利用凝胶液相色谱仪、扫描电子显微镜、傅里叶变换红外光谱仪、热重分析仪、X射线光电子能谱仪、X射线衍射仪和电子单纤维强力仪对PSZ纤维的化学结构、微观形貌、相组成和拉伸强度进行表征,探讨PSZ纤维的不熔化机理。结果表明:在80℃的条件下,碘蒸气不熔化仅需3 h即可将PSZ纤维转化为交联纤维,交联纤维经高温热解后得到抗拉强度为(1.53±0.27)GPa的SiCN陶瓷纤维。在交联过程中,Si—H和N—H被碘脱氢,在空气氛中重组为Si—O—Si和N—I,这有助于PSZ纤维的不熔化。与空气不熔化相比,该方法具有不熔化温度低,不熔化效率高等优点。In order to explore the iodine vapor curing mechanism of polysilazane fibers,continuous fine diameter polysilazane(PSZ)fibers with the diameter of 6.5μm were prepared using methyldichlorosilane and dimethyldichlorosilane as raw materials by the precursor conversion method,and PSZ cured fibers were prepared by iodine vapor curing.Gel permeation chromatograph,scanning electron microscope,Fourier transform infrared spectrometer,thermogravimetric analyzer,X-ray photoelectron spectrometer,X-ray diffractometer and electronic single fiber strength tester were used to characterize the chemical structure,micro morphology,phase composition and tensile strength of the PSZ fibers,in order to investigate the curing mechanism of PSZ fibers.The results showed that the PSZ fibers could be converted into cured fibers in only three hours at 80℃by using iodine vapor curing.SiCN ceramic fibers with a tensile strength of(1.53±0.27)GPa were obtained after the cured fibers were pyrolyzed at high temperature.In the curing process,Si—H and N—H bonds were dehydrogenated by iodine and recombined into Si—O—Si and N—I in air atmosphere,which contributed to the curing of PSZ fibers.Compared with the air curing method,this method has the advantages of low curing temperature and high curing efficiency.

关 键 词：先驱体转化法 聚硅氮烷 交联纤维 碘蒸气不熔化 不熔化机理 不熔化效率 

分 类 号：TQ174[化学工程—陶瓷工业]