掺杂羧基化碳纳米管的纳米碳纤维前驱体的制备及表征

为获得结构完整、 性能优良的纳米碳纤维前驱体, 采用静电纺丝法制备了掺杂羧基化多壁碳纳米管(MWCNTs)的聚丙烯腈(PAN)纳米纤维. 用扫描电子显微镜、 偏振红外光谱、 透射电子显微镜、 拉曼光谱及拉伸性能测试等对杂化纳米纤维的微观结构和力学性能进行了研究, 分析了MWCNTs含量的影响. 实验结果表明, 5%(质量分数)的MWCNTs掺杂量为杂化纳米纤维直径的突变点, 且MWCNTs的加入有利于PAN分子链的取向, MWCNTs在PAN纤维中大体上沿纤维轴向取向分布. 3%MWCNTs/PAN杂化纳米纤维的拉伸强度和拉伸模量分别达到88.6 MPa和3.21 GPa.

Preparation and Characterization of the Precursor Nanofiber of Nano-Carbon Fibers with Carboxylated Carbon Nanotubes

In order to achieve the precursor nanofiber of nano-carbon fibers with integrated structure and good properties, hybrid polyacrylonitrile(PAN) nanofibers with different loading of carboxylated multi-walled carbon nanotubes(MWCNTs) were fabricated through electrospinning. Scanning electron microscopy(SEM), polarized FTIR spectroscopy, transmission electron microscopy(TEM), Raman spectroscopy and the tensile test were adopted to study the microstructure and mechanical property of the hybrid nanofiber. The diameter of PAN nanofibers was decreasing with the adding of MWCNTs, but the sample containing 5%(mass fraction) MWCNTs displayed a diameter mutation. The experimental results showed that adding MWCNTs into the polymer was propitious for the orientation of molecular chains. Most of MWCNTs embedded in the PAN and aligned along the fiber axis. When the concentration of MWCNTs was below 5%, the tensile strength and modulus of PAN nanofibers were both enhanced with the loading of MWCNTs, which respectively reached to 88.6 MPa and 3.21 GPa after adding 3% MWCNTs.