大丝束PAN纤维热反应特性及其在连续预氧化过程中的结构性能演变  

Thermal reaction characteristics of large tow PAN precursors and their evolution of structure and properties during continuous pre-oxidation

作　　者：陈肖寒 郭利闯 黄翔宇 王晓旭[3] 刘杰[3] 王春华 CHEN Xiaohan;GUO Lichuang;HUANG Xiangyu;WANG Xiaoxu;LIU Jie;WANG Chunhua(Research Center of Carbon Fiber Engineering and Technology,Beijing University of Chemical Technology Changzhou Institute of Advanced Materials,Changzhou 213164,China;Shanghai Petrochemical CO.,LTD.,Shanghai 200540,China;College of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]北京化工大学常州先进材料研究院碳纤维工程与技术研究中心,常州213164 [2]上海石油化工股份有限公司,上海200540 [3]北京化工大学材料科学与工程学院,北京100029

出　　处：《复合材料学报》2023年第1期151-159,共9页Acta Materiae Compositae Sinica

基　　金：常州市应用基础研究计划(CJ20210029)。

摘　　要：利用热应力、DSC、FTIR、元素分析(EA)、XRD及力学性能、密度等测试表征手段,结合小丝束(24K)聚丙烯腈(PAN)原丝,解析了大丝束(48K)PAN原丝的热反应特性,并采用50 min连续预氧化制备高性能大丝束碳纤维,研究了大丝束PAN原丝连续预氧化过程中的结构性能演变规律。结果表明,大丝束PAN纤维的化学热应力是小丝束的1.13~1.43倍,且启动温度更低,当温度为250℃时,化学热应力差值最大,对应大丝束纤维密度为1.316 g/cm^(3);纤维内准晶区在反应初期即大量转化为无定形状态,准晶区晶粒尺寸呈现先增大后减小的趋势;50 min连续预氧化制备的大丝束碳纤维单丝拉伸强度和拉伸模量分别为4240 MPa和244 GPa,相关力学性能达到市售国外大丝束碳纤维同等水平。Thermal stress,DSC,FTIR,element analysis(EA),XRD,mechanical properties and density were used to analyze the thermal reaction characteristics of large tow polyacrylonitrile(PAN)precursors(48K)in combination with small tow PAN precursors(24K).The large tow carbon fibers were prepared by 50 min continuous pre-oxidation method,in which the evolution of structure and properties were studied.The results show that the thermal stress of large tow PAN precursors is 1.13-1.43 times of small tow PAN precursors,and the starting temperature is lower.The difference of thermal stress reaches maximum at 250℃and the corresponding density of large tow fibers is 1.316 g/cm^(3).The crystal regions of PAN precursors transform into amorphous regions rapidly at the initial stage of reaction,and the grain size of the crystal regions increases first and then decreases.The monofilament tensile strength and modulus of large tow carbon fibers prepared by 50 min continuous pre-oxidation are 4240 MPa and 244 GPa,respectively,which are at the same level as those commercial foreign large tow carbon fibers.

关 键 词：大丝束 碳纤维 预氧化 热应力 结构 性能 

分 类 号：TQ342.74[化学工程—化纤工业]