Jia Zhao#, Junliang Zhang#, Lei Wang, Jiakun Li, Tao Feng, Juncheng Fan, Lixin Chen* and Junwei Gu*. Superior wave-absorbing performances of silicone rubber composites via introducing covalently bonded SnO2@MWCNT absorbent with encapsulation structure. Composites Communications, 2020, 22: 100486 (2019IF=4.915)
(https://doi.org/10.1016/j.coco.2020.100486)
Abstract: 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(shù)的不斷發(fā)展，各類電子設(shè)備層出不窮，在給人類生活帶來(lái)巨大便利的同時(shí)也產(chǎn)生大量的電磁輻射。這些電磁輻射不僅影響電子設(shè)備的正常運(yùn)行，也會(huì)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(jīng)共混澆注制備SnO2@MWCNT/硅橡膠吸波復(fù)合材料。XRD、Raman、TGA、XPS和 TEM分析表明已成功合成Sn-C共價(jià)鍵連接具備封裝結(jié)構(gòu)的SnO2@MWCNT吸波劑。當(dāng)SnO2@MWCNT用量為7.5 wt%且試樣厚度為2.6 mm時(shí)，SnO2@MWCNT/硅橡膠吸波復(fù)合材料具有最優(yōu)的吸波性能，其最小反射損耗（RLmin）達(dá)到 -56.9 dB，對(duì)應(yīng)的有效吸收帶寬（EAB）達(dá)到3.1 GHz。優(yōu)異的吸波性能主要?dú)w因于SnO2@MWCNT/硅橡膠吸波復(fù)合材料良好的阻抗匹配和介電損耗能力。此時(shí)SnO2@MWCNT/硅橡膠吸波復(fù)合材料具有優(yōu)異的熱穩(wěn)定性，其耐熱指數(shù)（THRI）達(dá)到196.3oC，高于純硅橡膠的187.4oC。因此，這種SnO2@MWCNT/硅橡膠吸波復(fù)合材料在電磁防護(hù)領(lǐng)域具有廣闊的應(yīng)用前景。
