Qu Chen, Zhao Peng, Ren Yifan, Wu Chuandong, Liu Jiemin
School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Institute of Urban Safety and Environmental Science, Beijing Academy of Science and Technology, Beijing 100052, China.
Polymers (Basel). 2022 Aug 19;14(16):3401. doi: 10.3390/polym14163401.
For preparing high-performance electrospun fibers with functional molecules that cannot cross-entangle themselves, such as conductive polymers, promoting the aggregation of functional molecules on the surface by surface segregation is a promising approach. In the present study, electrospun polymethyl methacrylate/polyaniline (PMMA/PANI) fibers were prepared under various conditions, including solution composition, applied voltage, tip-to-collector distance, temperature, humidity, and gas-phase solvent concentration, to examine the effects of the parameters on fiber morphology and surface segregation. The changes in fiber morphology and variations in the intensity of PANI and PMMA's characteristic bands were investigated with scanning electron microscopy (SEM) and Raman spectroscopy. The results demonstrated that by changing the saturation difference and the viscosity, the amount of PMMA and PANI added significantly influenced whether surface segregation could occur. The effect of other investigated parameters on surface segregation was concluded to alter the molecular migratable time by affecting the jet flight time and the solvent volatilization rate. Among them, increasing the solvent concentration could significantly promote surface segregation without sacrificing morphological advantages. When the solvent concentration increased from 1.4 to 158 mg/m, the Raman peak intensity ratio of PANI and PMMA increased from 2.91 to 5.05, while the fiber diameter remained essentially constant.
对于制备含有无法相互交叉缠结的功能分子（如导电聚合物）的高性能电纺纤维而言，通过表面偏析促进功能分子在表面的聚集是一种很有前景的方法。在本研究中，在包括溶液组成、施加电压、针尖到收集器距离、温度、湿度和气态溶剂浓度等各种条件下制备了电纺聚甲基丙烯酸甲酯/聚苯胺（PMMA/PANI）纤维，以研究这些参数对纤维形态和表面偏析的影响。用扫描电子显微镜（SEM）和拉曼光谱研究了纤维形态的变化以及PANI和PMMA特征带强度的变化。结果表明，通过改变饱和度差异和粘度，添加的PMMA和PANI的量显著影响是否会发生表面偏析。得出的结论是，其他研究参数对表面偏析的影响是通过影响射流飞行时间和溶剂挥发速率来改变分子可迁移时间。其中，增加溶剂浓度可显著促进表面偏析，而不牺牲形态优势。当溶剂浓度从1.4增加到158mg/m时，PANI和PMMA的拉曼峰强度比从2.91增加到5.05，而纤维直径基本保持不变。
