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Abstract：
The integration of surface-modified multiwalled carbon nanotubes (fMWCNTs) into polymer nanocomposites has been extensively studied for their potential to enhance dielectric properties. This study, however, pioneers the use of a novel hybrid filler comprising fMWCNTs coated with metal nanoparticles, specifically aimed at augmenting the dielectric performance of polymers. In our research, poly(vinylidene fluoride) (PVDF) nanocomposite films were synthesized using fMWCNTs with a diameter of ∼6-9 nm and a length of 5 μm, adorned with gold nanoparticles (nAu) of ∼5.4 ± 0.9 nm via an adapted Turkevich method. Comprehensive analyses were conducted on nAu-fMWCNTs hybrid powder and their nanocomposites in PVDF with varying filler concentrations, confirming the formation of nAu-fMWCNTs with a weight ratio of 1.1 : 98.9. Three-phase percolative nanocomposites were produced by dispersing the hybrid filler in N,N-dimethylformamide, facilitated by interactions between the negative charge of nAu-fMWCNTs (zeta potential of ∼ -40.43 ± 0.46 mV) and polar phases of PVDF. This was verified through zeta potential and Fourier-transform infrared spectroscopy analyses. The dielectric permittivity (ε\') of the nanocomposites significantly increased from 17.8 to 524.8 (at 1 kHz) with filler loadings from 0.005 to 0.01 vol%, while the dielectric loss tangent (tanδ) showed a minor increase from 0.05 to 1.18. These enhancements are attributed to the elevated permittivity of nAu-fMWCNTs hybrid powder, PVDF\'s transition to the β-phase, and interfacial polarization effects. The restrained growth of nAu on fMWCNTs and the inhibition of conductive pathways in the polymer matrix contributed to the low tanδ values.
摘要：
将表面改性的多壁碳纳米管（fMWCNT）集成到聚合物纳米复合材料中已被广泛研究，以提高介电性能。这项研究,然而,先驱使用一种新型的混合填料，该填料包括涂覆有金属纳米颗粒的fMWCNT，专门旨在提高聚合物的介电性能。在我们的研究中,聚偏氟乙烯(PVDF)纳米复合薄膜是使用直径为~6-9nm，长度为5μm的fMWCNT合成的，通过适应的Turkevich方法装饰有~5.4±0.9nm的金纳米粒子(nAu)。对nAu-fMWCNTs杂化粉末及其在不同填料浓度的PVDF中的纳米复合材料进行了综合分析，确认重量比为1.1:98.9的nAu-fMWCNT的形成。通过将杂化填料分散在N，N-二甲基甲酰胺,nAu-fMWCNTs的负电荷(zeta电位~-40.43±0.46mV)与PVDF极性相之间的相互作用促进。通过zeta电位和傅里叶变换红外光谱分析验证了这一点。纳米复合材料的介电常数（ε'）从17.8显着增加到524.8（在1kHz），填料负载从0.005到0.01vol％，而介电损耗角正切(tanδ)显示出从0.05到1.18的微小增加。这些增强归因于nAu-fMWCNTs混合粉末的介电常数升高，PVDF向β相的转变，和界面极化效应。nAu在fMWCNT上的抑制生长和聚合物基质中导电途径的抑制导致了低tanδ值。
