通过熔融共混、流延成膜法制备了多壁碳纳米管/聚乙烯醇(MWCNTs/PVA)复合材料,并研究了碳纤维作为增强体的作用。扫描电子显微镜、傅里叶变换红外光谱、热重分析表明:MWCNTs在PVA基体中均匀分散且形成了良好的空间导电网络;MWCNTs的加入会使吸收峰转移并与PVA发生键合反应;MWCNTs/PVA复合材料具有优异的热稳定性,热分解温度低于105℃时只有少量水分蒸发。导电性和电磁屏蔽测试表明,MWCNTs/PVA复合材料电磁屏蔽性能随其导电性的增强而提高,MWCNTs质量分数为1.2%的复合材料样品,在干扰电磁波频率为1~18GHz频段上具有良好的屏蔽性能,当干扰电磁波频率为13.3GHz时,其屏蔽效能为36.7dB。碳纤维可以增强MWCNTs/PVA复合材料的屏蔽性能,MWCNTs质量分数为0.6%的碳纤维增强MWCNTs/PVA复合材料样品,在干扰电磁波频率为1~18GHz频段时,其电磁屏蔽效能大于40dB。
Multiwalled carbon nanotubes/polyvinyl alcohol (MWCNTs/PVA) composite films were prepared by melt blending and casting film forming method,and the effect of carbon fiber as reinforcements was studied.SEM showed that MWCNTs was uniformly dispersed in the PVA matrix and formed a good spatial conductive network.FT-IR analysis showed that the addition of MWCNTs would make the absorption peak transfer and the bonding reaction with PVA took place.Excellent thermal stability had only a small amount of water evaporation when below 105℃.Electrical conductivity and electromagnetic shielding tests shown that the electromagnetic shielding performance of MWCNTs/PVA-1.2wt% samples was improved with the increase of electrical conductivity.The shielding peak value of MWCNTs/PVA-1.2wt% samples was 36.7dB,when the interference frequency was 13.3GHz.At the same time,carbon fiber can enhance the shielding performance of MWCNTs/PVA film.The electromagnetic shielding efficiency of CF-MWCNTs/PVA-0.6wt% sample was greater than 40dB in 1~18GHz band.
[1] Maserang W L,Wright J W.Electromagnetic interference shielding device for a portable aircraft engine tester:US,4884171[P].1989-12-15.
[2] Shah T,Jones M,Alberding M,et al.Carbon nanostructures for electromagnetic shielding and lightning strike protection applications in aircraft[C]//The Workshop on Aerospace Emc.IEEE,2012:1-5.
[3] Chung D D L.Carbon materials for structural self-sensing,electromagnetic shielding and thermal interfacing[J].Carbon,2012,50(9):3342-3353.
[4] 杨玉山,董发勤,郑凯.膨胀石墨/金属网/ABS复合材料电磁屏蔽性能的研究[J].功能材料,2013,44(7):966-969.
[5] Hong Y K,Lee C Y,Jeong C K,et al.Electromagnetic interference shielding characteristics of fabric complexes coated with conductive polypyrrole and thermally evaporated Ag[J].Current Applied Physics,2001,1(6):439-442.
[6] Liang J,Wang Y,Huang Y,et al.Electromagnetic interference shielding of graphene/epoxy composites[J].Carbon,2009,47(3):922-925.
[7] Jiaxing H,James A M,J Henry A,et al.Mechanochemical route to the conducting polymer polyaniline[J].Macromolecules,2016,38(2):317-321.
[8] Kuzhir P,Paddubskaya A,Bychanok D,et al.Microwave probing of nanocarbon based epoxy resin composite films:toward electromagnetic shielding[J].Thin Solid Films,2016,519(12):4114-4118.
[9] Shao Z G,Wang X,Hsing I M.Composite nafion/polyvinyl alcohol membranes for the direct methanol fuel cell[J].Journal of Membrane Science,2002,210(1):147-153.
[10] Ren J,Yu D.Effects of enhanced hydrogen bonding on the mechanical properties of poly (vinyl alcohol)/carbon nanotubes nanocomposites[J].Composite Interfaces,2018,25(3):1-15.
[11] Falath W,Sabir A,Jacob K I.Highly improved reverse osmosis performance of novel PVA/DGEBA cross-linked membranes by incorporation of Pluronic F-127 and MWCNTs for water desalination[J].Desalination,2016,397:53-66.
[12] Kumar K N,Padma R,Vijayalakshmi L,et al.Promising red emission from functionalized multi walled carbon nanotubes embedded co-doped Bi3++Eu3+:PVA polymer nanocomposites for photonic applications[J].Journal of Luminescence,2017,182:208-219.
[13] Yue Z,Yu M Y,Lan X.Study on properties of carbon nanotubes/epoxy resin composite prepared by in situ polymerization[J].Advanced Materials Research,2013,750-752:132-135.
[14] Li N,Huang Y,Du F,et al.Electromagnetic interference (EMI) shielding of single-walled carbon nanotube epoxy composites[J].Nano Letters,2006,6(6):1141-1145.