Tian Ming, Zhang Jing, Zhang Liqun, Liu Suting, Zan Xiaoqing, Nishi Toshio, Ning Nanying
State Key Lab of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China.
Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China.
J Colloid Interface Sci. 2014 Sep 15;430:249-56. doi: 10.1016/j.jcis.2014.05.034. Epub 2014 Jun 2.
A dielectric composite with high dielectric constant, low dielectric loss and low percolation threshold was prepared by using the combined strategy of encapsulating of graphene oxide nanosheets (GONS) on carboxylated nitrile rubber (XNBR) latex particles and the in situ thermal reduction in GONS at a moderate temperature. The encapsulation of GONS on XNBR latex particles was mainly realized via the hydrogen bonding interactions between GONS and XNBR during latex mixing. A segregated graphene network was obtained at a low content of thermally reduced graphene (TRG), resulting in a low percolation threshold (0.25 vol.%). The dielectric constant at 100 Hz obviously increased from 23 for pure XNBR to 2211 and 5542 for the composite with 0.5 vol.% and 0.75 vol.% of TRG, respectively. The dielectric loss of the composites retained at a low value (less than 1.5). Meanwhile, the elastic modulus only slightly increased with the presence of 0.1-0.5 vol.% of TRG, keeping the good flexibility of the dielectric composites. This study provides a simple, low-cost and effective method to prepare high performance dielectric composites, facilitating the wide application of dielectric materials.
通过采用在羧化丁腈橡胶（XNBR）胶乳颗粒上包覆氧化石墨烯纳米片（GONS）以及在适中温度下对GONS进行原位热还原的联合策略，制备了一种具有高介电常数、低介电损耗和低渗流阈值的介电复合材料。GONS在XNBR胶乳颗粒上的包覆主要是在胶乳混合过程中通过GONS与XNBR之间的氢键相互作用实现的。在低热还原石墨烯（TRG）含量下获得了一种隔离的石墨烯网络，从而导致低渗流阈值（0.25体积%）。100 Hz时的介电常数从纯XNBR的23明显增加到含0.5体积%和0.75体积%TRG的复合材料的2211和5542。复合材料的介电损耗保持在较低值（小于1.5）。同时，弹性模量仅在存在0.1 - 0.5体积%TRG时略有增加，保持了介电复合材料良好的柔韧性。本研究提供了一种简单、低成本且有效的方法来制备高性能介电复合材料，有利于介电材料的广泛应用。
