Kwon Youbin, Lee Byoung-Sun, Park Sarang, Yu Woong-Ryeol
Department of Materials Science and Engineering, Research Institute of Advanced Materials (RIAM), Seoul National University Seoul 08826 Republic of Korea
RSC Adv. 2019 Jun 28;9(35):20248-20255. doi: 10.1039/c9ra03945g. eCollection 2019 Jun 25.
Excellent mechanical, electrical, and thermal properties of graphene have been achieved at the macroscale by assembling individual graphene or graphene oxide (GO) particles. Wet-spinning is an efficient and well-established process that can provide GO assemblies in fiber form. The coagulation bath in the wet-spinning process has rarely been considered for the design of mechanically robust GO fibers (GOFs). In this study, locating the amidation reaction in the coagulation bath yielded mechanically improved GOFs. The imides 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and -hydroxysuccinimide were used to form covalent amide bonds between GO flakes and chitosan, thereby reinforcing the GOFs. Evidence and effects of the amidation reaction were systematically examined. The tensile strength and breaking strain of the GOFs improved by 41.6% and 75.2%, respectively, and the toughness almost doubled because of the optimized crosslinking reaction. Our work demonstrated that using a coagulation bath is a facile way to enhance the mechanical properties of GOFs.
通过组装单个石墨烯或氧化石墨烯（GO）颗粒，已在宏观尺度上实现了石墨烯优异的机械、电气和热性能。湿纺是一种高效且成熟的工艺，能够提供纤维形式的氧化石墨烯组件。在设计机械性能强大的氧化石墨烯纤维（GOF）时，很少会考虑湿纺过程中的凝固浴。在本研究中，将酰胺化反应置于凝固浴中可使氧化石墨烯纤维的机械性能得到改善。使用1-乙基-3-（3-二甲基氨基丙基）碳二亚胺和N-羟基琥珀酰亚胺形成氧化石墨烯薄片与壳聚糖之间的共价酰胺键，从而增强氧化石墨烯纤维。对酰胺化反应的证据和效果进行了系统研究。由于优化的交联反应，氧化石墨烯纤维的拉伸强度和断裂应变分别提高了41.6%和75.2%，韧性几乎翻倍。我们的工作表明，使用凝固浴是增强氧化石墨烯纤维机械性能的一种简便方法。
