[Composites Part A] Highly efficient thermal conductivity of polydimethylsiloxane composites via introducing “Line-Plane”-like hetero-structured fillers
writer：Shuangshuang Wang, Dianying Feng, He Guan, Yongqiang Guo*, Xia Liu, Chao Yan, Lei Zhang and Junwei G
keywords：Thermally conductive composites
source：期刊
specific source：Composites Part A: Applied Science and Manufacturing
Issue time：2022年
Shuangshuang Wang, Dianying Feng, He Guan, Yongqiang Guo*, Xia Liu, Chao Yan, Lei Zhang and Junwei Gu*. Highly efficient thermal conductivity of polydimethylsiloxane composites via introducing “Line-Plane”-like hetero-structured fillers. Composites Part A: Applied Science and Manufacturing, 2022, 157: 106911. 2020IF=7.664.（1區(qū)材料科學Top期刊）https://doi.org/10.1016/j.compositesa.2022.106911
Graphite oxide (GO) and cetyltrimethylammonium bromide (CTAB) modified multi-walled carbon nanotubes (m-MWCNTs) are utilized to fabricate "Line-Plane"-like hetero-structured thermally conductive GO@MWCNTs fillers by electrostatic self-assembly, which are then introduced into polydimethylsiloxane (PDMS) to fabricate thermally conductive GO@MWCNTs/PDMS composites. When the mass ratio of GO to m-MWCNTs is 2:1, GO@MWCNTs fillers have optimal morphologies and thermal conductivity contribution. When the mass fraction of GO@MWCNTs is 20 wt%, the thermal conductivity coefficient (λ) of GO@MWCNTs/PDMS composites reaches 2.10 W/(m·K), 950% higher than that of pure PDMS (0.20 W/(m·K)), which is also superior to the λ of MWCNTs/PDMS (0.68 W/(m·K)), GO/PDMS (1.59 W/(m·K)) and (GO/MWCNTs)/PDMS (1.28 W/(m·K)) composites with the same amount of single or hybrid thermally conductive fillers. Meantime, the GO@MWCNTs/PDMS composites also present good thermal conduction stability (average λ after 15 heating-cooling cycles in the temperature of 21 to 100oC is 2.14 W/(m·K)) and thermal stability (heat resistance index is 249.3oC).
本文以聚二甲基硅氧烷（PDMS）為基體，以氧化石墨（GO）和十六烷基三甲基溴化銨改性多壁碳納米管（MWCNTs）靜電自組裝制備的“線-面”狀異質(zhì)結(jié)構(gòu)GO@MWCNTs為導熱填料，經(jīng)共混復合-澆注成型制備GO@MWCNTs/PDMS導熱復合材料。當GO和m-MWCNTs質(zhì)量比為2：1，GO@MWCNTs導熱填料具有最佳的形貌特征和最優(yōu)的導熱貢獻力。且當GO@MWCNTs質(zhì)量分數(shù)為20 wt%時，GO@MWCNTs/PDMS導熱復合材料的導熱系數(shù)（λ）為2.10 W/(m·K)，較純PDMS的λ（0.20 W/(m·K)）提高了950%，也優(yōu)于相同導熱填料用量下的MWCNTs/PDMS（0.68 W/(m·K)）、GO/PDMS（1.59 W/(m·K)）和(GO/MWCNTs)/PDMS（1.28 W/(m·K)）復合材料的λ。此時，GO@MWCNTs/PDMS導熱復合材料還具有良好的導熱穩(wěn)定性（21~100℃溫度范圍15次加熱-冷卻循環(huán)后的λ平均值為2.14 W/(m·K)）和熱穩(wěn)定性。