热处理升温速率对中空多孔炭纤维介电常数的影响  

Effect of Heating Rate on the Complex Permittivity of Hollow-porous Carbon Fibers

作　　者：谢炜[1] 程海峰[2] 匡加才[3] 陈朝辉[2] 楚增勇[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]国防科技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：《无机材料学报》2011年第9期939-943,共5页Journal of Inorganic Materials

基　　金：国家自然科学基金(50403010);湖南省自然科学基金(08JJ3100);湖南省科技计划项目(2010FJ4094)~~

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,研究了预氧化和炭化升温速率对其微观结构、元素组成、电导率和介电常数的影响.研究结果表明,热处理升温速率对中空多孔炭纤维微观结构影响很大.随热处理升温速率增大,所得中空多孔炭纤维体电导率和介电常数依次降低.预氧化升温速率为0.5℃/min所得炭纤维体电导率为1997.14 S/m,4℃/min时下降到153.39 S/m,中空多孔炭纤维/石蜡复合材料介电常数的ε″则从70.35降低到6.99.热处理升温速率引起中空多孔炭纤维碳含量和孔隙的变化,可用来调节中空多孔炭纤维的电导率和介电常数.A series of polyacrylonitrile-based hollow-porous carbon fibres（PAN-HPCFs） were prepared by oxi-dating PAN hollow-porous fibers in air and carbonizing their cured fibers in nitrogen.The effects of preoxidation and carbonization heating rate on the microstructure,composition,electrical volume conductivity and complex permittivity were investigated.The microstructure of the obtained PAN-HPCFs is changed greatly by the heating rate.The electrical volume conductivity and complex permittivity decrease with the increase of heating rate.The electrical volume conductivity is in the range 1997.14 S/m to 153.39 S/m with the preoxidation heating rate in-creasing from 0.5℃/min to 4℃/min.At 2 GHz,the value of ε″ of composites of paraffin and PAN-PHCFs de-creases from 70.35 to 6.99 when preoxidation heating rate increases form 0.5℃/min to 4℃/min.Results indicate that the electrical conductivity and complex permittivity of PAN-HPCFs can be adjusted by the heating rate.

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]