Eswaraiah Varrla, Sankaranarayanan Venkataraman, Ramaprabhu Sundara
Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials, Technology Centre (NFMTC), Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India.
Nanoscale Res Lett. 2011 Feb 14;6(1):137. doi: 10.1186/1556-276X-6-137.
Novel polymer nanocomposites comprising of MnO2 nanotubes (MNTs), functionalized multiwalled carbon nanotubes (f-MWCNTs), and polyvinylidene fluoride (PVDF) were synthesized. Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy. Electrical conductivity measurements were performed on these polymer composites using four probe technique. The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs) to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m). Electromagnetic interference shielding effectiveness (EMI SE) was measured with vector network analyzer using waveguide sample holder in X-band frequency range. EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.
合成了由二氧化锰纳米管（MNTs）、功能化多壁碳纳米管（f-MWCNTs）和聚偏氟乙烯（PVDF）组成的新型聚合物纳米复合材料。通过场发射扫描电子显微镜证实了f-MWCNTs和MNTs在PVDF基体中的均匀分布。使用四探针技术对这些聚合物复合材料进行电导率测量。向PVDF基体中添加2 wt.%的MNTs（2 wt.%，f-MWCNTs）会导致电导率从10-16S/m增加到4.5×10-5S/m（3.2×10-1S/m）。在X波段频率范围内，使用波导样品架通过矢量网络分析仪测量电磁干扰屏蔽效能（EMI SE）。与7 wt.%的f-MWCNTs的EMI SE约为18 dB相比，向PVDF中添加5 wt.%的MNTs-1 wt.%的f-MWCNTs可获得约20 dB的EMI SE,这表明当前的MNT/f-MWCNT/PVDF复合材料在X波段区域作为低成本EMI屏蔽材料的潜在用途。
