高介电常数低介电损耗PEG@graphene/PVDF复合材料的制备及性能研究

Fabrication and Characterization of PEG@graphene/PVDF Nanocomposite with High Permittivity and Low Loss

将单端氨基化聚乙二醇(PEG-NH2)接枝的石墨烯填充到聚偏氟乙烯(PVDF)基体中,通过溶液法制备了PEG@graphene/PVDF纳米复合材料,并借助扫描电子显微镜(SEM)、红外光谱(FTIR)、X射线衍射(XRD)、热重分析(TGA)以及阻抗分析仪等手段对复合材料的结构形貌及介电性能进行了分析表证。研究表明:改性的石墨烯具有较好的溶剂稳定性,能均匀分散在PVDF基体中,与基体界面结合良好;具有核壳结构的PEG@graphene有效提高了PVDF复合材料的介电常数,降低了介电损耗。PEG@graphene/PVDF质量分数3%复合材料的介电常数高达137,介电损耗为0.29(50 Hz)。

PEG@graphene/Polyvinylidene fluoride （PVDF） nanocomposite was fabricated by adding amino-polyethylene glycol monomethyl ether functionalized graphene via solution mixing method. The morphology, structure, and dielectric property of PEG@graphene/PVDF nancomposite were characterized by SEM, FTIR, XRD, TGA, and impedance analyz- er. Results show that the modified PEG@graphene has a good stability in many organic solvents, thus leading to a homogeneous dispersion and a better interfacial bonding within the PVDF matrix. The core-shell structure of PEG@graphene enables distinct enhancement in the permittivity and suppression in the dielectric loss of PEG@graphene/PVDF nancomposite. The permittivity for representative PEG@graphene/PVDF 3% （weight per- cent ）nanocomposite reaches as high as 137 with a low dielectric loss of only 0.29 at 50 Hz.