文献类型：期刊文献

英文题名：Core/shell-structured hyperbranched aromatic polyamide functionalized graphene nanosheets-poly(p-phenylene benzobisoxazole) nanocomposite films with improved dielectric properties and thermostability

作者：Feng, Hao[1];Ma, Wenjun[1];Cui, Zhong-Kai[2];Liu, Xiaoyun[1];Gu, Jinlou[1];Lin, Shaoliang[1];Zhuang, Qixin[1]

机构：[1]East China Univ Sci & Technol, Key Lab Adv Polymer Mat Shanghai, Key Lab Specially Funct Polymer Mat & Related Tec, Minist Educ,Sch Mat Sci & Engn, Shanghai 200237, Peoples R China;[2]Univ Montreal, Dept Chem, CP 6128,Succ Ctr Ville, Montreal, PQ H3C 3J7, Canada

年份：2017

卷号：5

期号：18

起止页码：8705

外文期刊名：JOURNAL OF MATERIALS CHEMISTRY A

收录：;EI(收录号：20172803899288);WOS:【SCI-EXPANDED(收录号:WOS:000400983400058)】；

基金：This work was financially supported by the National Natural Science Foundation of China (51573045), the International Collaboration Research Program of Science and Technology Commission of Shanghai (16520722000) and the Key Laboratory of Advanced Polymer Materials of Shanghai (Grant No. ZD20150202).

语种：英文

外文关键词：Nanocomposites - Elastic moduli - Electric breakdown - Cyclization - Graphene - Dielectric materials - Nanosheets - Stability - Aromatic compounds - Dielectric properties of solids - Nanocomposite films - Oxide films - Tensile strength - Dielectric devices

摘要：This study reports the synthesis of core/shell-structured hyperbranched aromatic polyamide functionalized graphene nanosheets-poly(p-phenylene benzobisoxazole) (GNs-HAP-PBO) nanocomposite films with improved dielectric properties and thermostability. PBO precursor polymer chains were grafted onto the ample amino-terminated GNs-HAP via in situ polymerization, and then the reduction of GNs-HAP and the intramolecular cyclization of PBO precursors were achieved through thermal treatment. The unique core/shell-structure is effective to prevent the aggregation of GNs and improves the dispersion of GNs in the GNs-HAP-PBO nanocomposites, forming microcapacitor networks in the matrix. The GNs-HAP-PBO nanocomposite films exhibit lower dielectric loss in comparison with solvothermally reduced graphene oxide/PBO nanocomposite films. At 1 kHz and 200 degrees C, a dielectric constant of 66.27 and a dielectric loss of 0.045 are observed in the GNs-HAP-PBO nanocomposite films with 2 wt% GNs-HAP. Moreover, the maximum energy density of the GNs-HAP-PBO nanocomposite films is up to 6 J cm(-3) owing to the high breakdown strength (132.5 +/- 9.3 kV mm(-1)). The GNs-HAP-PBO nanocomposite films with 2 wt% GNs-HAP also exhibit excellent tensile strength (125 MPa), Young's modulus (6.4 GPa), and high thermal stability (temperature of 5 wt% loss = 643 degrees C). This work demonstrates a promising strategic approach to fabricating high dielectric materials under extreme environments.