Qiao Mengmeng, Kong Haijuan, Ding Xiaoma, Zhang Luwei, Yu Muhuo
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Shanghai Key Laboratory of Lightweight Composite, Donghua University Shanghai 201620 China
School of Materials Engineering, Shanghai University of Engineering Science Shanghai 201620 China
RSC Adv. 2019 Sep 6;9(48):28146-28152. doi: 10.1039/c9ra04732h. eCollection 2019 Sep 3.
In this paper, graphene oxide (GO) was successfully prepared by the modified Hummers' method and then uniformly dispersed in an aqueous solution containing a small amount of polyvinyl alcohol (PVA) as an adhesive. The solution was uniformly coated on the surface of polyacrylonitrile (PAN) fibers and then the fibers were pre-oxidized at 240 °C for 20 min in the air. The pre-oxidation degree of PAN fibers and fibers coated with different contents of GO was analyzed by the Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). In addition, the surface and cross-section of PAN fibers before and after pre-oxidation were observed by scanning electron microscopy (SEM). The experimental results showed that the presence of GO coatings significantly improved the pre-oxidation degree of PAN fibers, at the same time, the pre-oxidation degree of PAN fibers increased with the increase of GO contents from 0.2 to 1.0 mg ml. The cross-section morphology of the pre-oxidized PAN fibers revealed that the degree of pre-oxidation inside fibers was uniform. This was because the GO coatings acted as a medium to transfer heat, removing the heat released during the pre-oxidation process and increasing the pre-oxidation degree.
在本文中，采用改进的Hummers法成功制备了氧化石墨烯（GO），然后将其均匀分散在含有少量作为粘合剂的聚乙烯醇（PVA）的水溶液中。将该溶液均匀涂覆在聚丙烯腈（PAN）纤维表面，然后将纤维在空气中于240℃预氧化20分钟。通过傅里叶变换红外（FT-IR）光谱、差示扫描量热法（DSC）、X射线衍射（XRD）和热重分析（TGA）分析了PAN纤维和涂覆不同含量GO的纤维的预氧化程度。此外，通过扫描电子显微镜（SEM）观察了预氧化前后PAN纤维的表面和横截面。实验结果表明，GO涂层的存在显著提高了PAN纤维的预氧化程度，同时，PAN纤维的预氧化程度随着GO含量从0.2增加到1.0 mg/ml而增加。预氧化PAN纤维的横截面形态表明纤维内部的预氧化程度是均匀的。这是因为GO涂层起到了传递热量的介质作用，带走了预氧化过程中释放的热量并提高了预氧化程度。
