炭化气流诱导效应对聚丙烯腈基碳纤维微观结构和力学性能的影响  

Effect of carbonization airflow on the aggregation structure and mechanical properties of polyacrylonitrile based carbon fibers

作　　者：刘杰[1] 牛鹏飞[1] 薛岩[1] 梁节英[1] 

机构地区：[1]北京化工大学材料科学与工程学院碳纤维及功能高分子教育部重点实验室,北京100029

出　　处：《北京化工大学学报（自然科学版）》2014年第3期51-57,共7页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家自然科学基金(51073011)

摘　　要：采用广角X射线衍射(WAXD)、气相色谱(GC)、元素分析(EA)、扫描电子显微镜(SEM)等表征手段定量分析了炭化气流诱导效应对聚丙烯腈(PAN)基碳纤维聚集态结构及力学性能的影响。结果表明,PAN基碳纤维密度与炭化气流具有显著关联性,逆向气流可有效提高纤维密度,改善致密性;PAN基碳纤维的晶区含量同时取决于晶粒的大小和数量,逆向炭化气流有利于小晶粒的形成和晶区含量的提高,并对孔隙的形成具有抑制作用。保持炭化逆向气流比为3时,所得PAN基碳纤维的微晶尺寸(1.52 nm)较小,晶区含量(35.2%)最高,孔隙率(16.2%)较低,此时拉伸强度(4.03 GPa)最高,比正向气流条件下制备的PAN基碳纤维的拉伸强度提升了35.7%。The effect of carbonization airflow on the aggregation structure and mechanical properties of polyacrylonitrile( PAN) based carbon fibers has been quantitatively investigated by means of wide angle X-ray diffraction( WAXD),gas chromatography( GC),elemental analysis( EA) and scanning electron microscopy( SEM). The results indicate that the density of PAN-based carbon fibers depends significantly on the carbonization airflow induction,and increased markedly when using a reverse airflow. The crystallinity of the carbon fibers depends on the grain size and quantity. Reverse airflow of the carbonization atmosphere favors the formation of small crystalline grains and a reduced number of pores. When the ratio of reverse airflow( R0) is 3. 0,the microcrystallite size( 1. 52nm) and the porosity( 16. 2%) of the PAN-based carbon fibers both have their lowest values whilst the crystallinity( 35. 2%) is the highest; these PAN-based carbon fibers possess the highest tensile strength of 4. 03 GPa which is 35. 7% higher than other carbon fibers obtained under forward airflow.

关 键 词：聚丙烯腈 炭化气流 微晶结构 孔隙率 力学性能 碳纤维 

分 类 号：TQ342.742[化学工程—化纤工业]