[Composites Communications]Superior wave-absorbing performances of silicone rubber composites via introducing covalently bonded SnO2@MWCNT absorbent with encapsulation structure
作者：Jia Zhao#, Junliang Zhang#, Lei Wang, Jiakun Li, Tao Feng, Juncheng Fan, Lixin Chen* and Junwei Gu*
關鍵字：wave-absorbing
論文來源：期刊
發表時間：2020年
With the rapid development of electronic communication technology, all kinds of electronic equipments have emerged in an endless stream, which generate a lot of unavoidable electromagnetic radiations while bring huge convenience to human life. These electromagnetic radiations not only affect the normal operation of electronic equipments, but also do harm to human health, and therefore it is particularly urgent to investigate the electromagnetic wave-absorbing materials. In this work, SnO2@MWCNT wave absorbent was firstly fabricated via a hydrothermal process followed by heat treatment. Then SnO2@MWCNT/silicone rubber wave-absorbing composites were obtained by solution casting method. XRD, Raman, TGA, XPS, and TEM analyses indicated the successful preparation of covalently bonded SnO2@MWCNT absorbent with encapsulation structure. When the mass fraction of SnO2@MWCNT was 7.5 wt% and the sample thickness was 2.6 mm, the SnO2@MWCNT/silicone rubber wave-absorbing composite displayed the minimum reflection loss (RLmin) of -56.9 dB and effective absorption bandwidth (EAB) of 3.1 GHz. The outstanding wave-absorbing performances of SnO2@MWCNT/silicone rubber wave-absorbing composites could be ascribed to the excellent impedance matching and dielectric loss capability. Furthermore, the corresponding 7.5 wt% SnO2@MWCNT/silicone rubber wave-absorbing composite exhibited heat resistance index (THRI) of 196.3oC, higher than that of neat silicone rubber (187.4oC). Our fabricated SnO2@MWCNT/silicone rubber wave-absorbing composites possess potential applications in the field of electromagnetic protection.隨著電子通訊技術的不斷發展，各類電子設備層出不窮，在給人類生活帶來巨大便利的同時也產生大量的電磁輻射。這些電磁輻射不僅影響電子設備的正常運行，也會危害人類的健康。因此，電磁波吸收材料（吸波材料）的研究就顯得尤為迫切。本文以硅橡膠為基體，以水熱法和后熱處理制備合成的SnO2@MWCNT為吸波劑，經共混澆注制備SnO2@MWCNT/硅橡膠吸波復合材料。XRD、Raman、TGA、XPS和 TEM分析表明已成功合成Sn-C共價鍵連接具備封裝結構的SnO2@MWCNT吸波劑。當SnO2@MWCNT用量為7.5 wt%且試樣厚度為2.6 mm時，SnO2@MWCNT/硅橡膠吸波復合材料具有最優的吸波性能，其最小反射損耗（RLmin）達到 -56.9 dB，對應的有效吸收帶寬（EAB）達到3.1 GHz。優異的吸波性能主要歸因于SnO2@MWCNT/硅橡膠吸波復合材料良好的阻抗匹配和介電損耗能力。此時SnO2@MWCNT/硅橡膠吸波復合材料具有優異的熱穩定性，其耐熱指數（THRI）達到196.3oC，高于純硅橡膠的187.4oC。因此，這種SnO2@MWCNT/硅橡膠吸波復合材料在電磁防護領域具有廣闊的應用前景。