预氧化温度对中空多孔炭纤维介电常数的影响  

Effect of Preoxidation Temperature on the Complex Permittivity of Hollow-porous Carbon Fibers

作　　者：谢炜[1] 程海峰[2] 匡加才[3] 楚增勇[2] 陈朝辉[2] 龙春光[1] 

机构地区：[1]长沙理工大学汽车与机械工程学院,长沙410114 [2]国防科学技术大学新型陶瓷纤维及其复合材料国防科技重点实验室,长沙410073 [3]长沙理工大学材料科学与工程研究所,长沙410114

出　　处：《材料导报》2011年第10期44-47,共4页Materials Reports

基　　金：湖南省自然科学基金(08JJ3100);湖南省科技计划项目(2010FJ4094);长沙理工大学公路工程省部共建教育部重点实验室开放基金(kfj090109)

摘　　要：以中空多孔聚丙烯腈(PAN)原丝为原料,通过预氧化和炭化工艺制备了中空多孔炭纤维。研究了预氧化温度对其微观结构、元素组成和介电常数的影响。结果表明,预氧化温度对中空多孔炭纤维微观结构的影响不大;碳含量随预氧化温度的升高而减少,而氮、氧含量则相反。随预氧化温度的升高,所得中空多孔炭纤维的介电常数依次降低。在2GHz处,预氧化温度为250℃时ε′和ε″分别为23.12和73.51,而预氧化温度为310℃时ε′和ε″分别为19.32和9.87。因此,可通过预氧化温度来调节中空多孔炭纤维的介电常数。A series of polyacrylonitrile-based hollow-porous carbon fihres（PAN-HPCFs） were prepared by oxidating in air and carbonizing in nitrogen to get lightweight radar wave absorbers. The effects of preoxidation tempera- ture on the microstructure, composition and complex permittivity of the resultant PAN-HPCFs were investigated. Resuits indicate that the microstructure of the obtained PAN-HPCFs has not been effeeted by changing the preoxidation temperature. The C content of PAN-HPCF decreases with the increase of preoxidation temperature. The real and imaginary part of the complex permittivity（ε＇ and ε＂） decrease with the increase of preoxidation temperature. The values of ε＇ and ε＂ of composites of paraffin and PAN-PHCFs are 23. 12 and 73. 51 when preoxidation temperature is 250℃, 19. 32 and 9. 87 when preoxidation temperature is 310℃, and carbonization temperature is 800℃. The complex permittivity of PAN-HPCFs can be adjusted by heat-treatment process.

关 键 词：中空多孔炭纤维 预氧化 炭化 介电常数 

分 类 号：TB34[一般工业技术—材料科学与工程]