Hsiao Sheng-Tsung, Ma Chen-Chi M, Tien Hsi-Wen, Liao Wei-Hao, Wang Yu-Sheng, Li Shin-Ming, Yang Chih-Yu, Lin Sheng-Chi, Yang Ruey-Bin
Department of Chemical Engineering, National Tsing-Hua University , Hsin-Chu 30013, Taiwan, ROC.
ACS Appl Mater Interfaces. 2015 Feb 4;7(4):2817-26. doi: 10.1021/am508069v. Epub 2015 Jan 22.
Flexible and lightweight graphene nanosheet (GN)/waterborne polyurethane (WPU) composites which exhibit high electrical conductivity and electromagnetic shielding performance were prepared. Covalently modifying GNs with aminoethyl methacrylate (AEMA; AEMA-GNs) through free radical polymerization effectively inhibited the restacking and aggregation of the GNs because of the -NH3(+) functional groups grafted on the AEMA-GNs. Moreover, the AEMA-GNs exhibited high compatibility with a WPU matrix with grafted sulfonated functional groups because of the electrostatic attraction, which caused the AEMA-GNs to homogeneously disperse in the WPU matrix. This homogeneous distribution enabled the GNs to form electrically conductive networks. Furthermore, AEMA-GNs with different amounts of AEMA segments were introduced into the WPU matrix, and the effects of the surface chemistry of the GNs on the electrical conductivity and EMI shielding performance of composites were investigated. AEMA-GN/WPU composites with a GN loading of 5 vol % exhibited remarkable electrical conductivity (approximately 43.64 S/m) and EMI shielding effectiveness (38 dB) over the frequency of 8.2 to 12.4 GHz.
制备了具有高导电性和电磁屏蔽性能的柔性轻质石墨烯纳米片（GN）/水性聚氨酯（WPU）复合材料。通过自由基聚合用甲基丙烯酸氨基乙酯（AEMA；AEMA - GN）对GNs进行共价改性，由于接枝在AEMA - GNs上的 - NH3(+)官能团，有效地抑制了GNs的重新堆叠和聚集。此外，由于静电吸引，AEMA - GNs与带有接枝磺化官能团的WPU基体表现出高相容性，这使得AEMA - GNs在WPU基体中均匀分散。这种均匀分布使GNs形成导电网络。此外，将不同量AEMA链段的AEMA - GNs引入WPU基体中，研究了GNs的表面化学对复合材料导电性和电磁干扰屏蔽性能的影响。GN负载量为5体积%的AEMA - GN/WPU复合材料在8.2至12.4 GHz频率范围内表现出显著的导电性（约43.64 S/m）和电磁干扰屏蔽效能（38 dB）。
