PDF《磁性石墨烯的制备初探》

包装工程第38 卷第13 期・32・ PACKAGING ENGINEERING

2017 年7月收稿日期:2017-03-21 基金项目:国家重点研发计划(2016YFD0600703) 作者简介:郭露(1994―) ,女,南京林业大学硕士生,主攻石墨烯复合材料.

通讯作者:徐长妍(1967―) ,女,博士,南京林业大学副教授,主要研究方向为包装材料、包装工艺和运输包装. 磁性石墨烯的制备初探 郭露,徐长妍,王希,林扬帆,李忆佳,季伟 (南京林业大学,南京 210037) 摘要:目的 制备磁性石墨烯,实现其定向排列,为进一步制备性能良好的热界面材料提供定向导热相. 方法 采用聚合物包覆和层层组装技术,在石墨烯表面均匀包覆带负电荷的聚磺苯乙烯(PSS)聚电解质 层,然后在静电力作用下包覆一层带正电荷的聚二烯丙基二甲基氯化铵(PDDA)聚电解质.最后,借助 静电力使带负电荷的磁性 Fe3O4 纳米粒子在附着有 PDDA 层的石墨烯表面形成均匀的致密覆盖层, 得到 磁性石墨烯,并在外磁场作用下使磁性石墨烯进行定向排列.结果 采用聚电解质层层组装技术可有效 地对石墨烯进行磁性化处理;

粉状石墨烯比片状石墨烯定向排列效果明显;

以片状石墨烯为原材料的实 验条件下,加入聚电解 PSS、PDDA 的量越多,磁性化效果更佳.结论 通过聚电解质层层组装技术可 有效地对石墨烯进行磁性化处理,并在磁场作用下实现定向排列. 关键词:石墨烯;

磁性化;

定向排列;

制备方法 中图分类号:TB484.9 文献标识码:A 文章编号:1001-3563(2017)13-0032-04 Preparation of Magnetic Graphene GUO Lu, XU Chang-yan, WANG Xi, LIN Yang-fan, LI Yi-jia, JIA Wei (Nanjing Forestry University, Nanjing 210037, China) ABSTRACT: The work aims to prepare magnetic graphene and achieve its alignment, in order to provide a directional thermal phase for further preparation of well-formed thermal interface materials. By means of polymer cladding and layer-by-layer assembly technique, the graphene surface uniformly was coated with a negatively charged polystyrene su- lronate (PSS) polyelectrolyte layer firstly, and then under the action of electrostatic force, it was coated with a layer of positively charged poly diallyldimethyl ammonium chloride (PDDA) polyelectrolyte, and finally by means of an elec- trostatic force, the negatively charged Fe3O4 magnetic nanoparticles formed a uniform dense covering layer on the gra- phene surface attached with PDDA layer, to obtain magnetic graphene. The magnetic graphene was aligned under the ex- ternal magnetic field. The results showed that the graphene could be magnetized effectively by the polyelectrolyte layer-by-layer assembly technique. The alignment effect of powdery graphene was better than that of flaky graphene. The more the polyelectrolyte PSS and PDDA were added, the better the magnetic effect was, under the experimental condi- tions that took flaky graphene as raw material. By using the polyelectrolyte layer-by-layer assembly technique, the gra- phene can be magnetized effectively and aligned under the action of the magnetic field. KEY WORDS: graphene;

magnetization;

alignment;

preparation method 随着当代电子技术的迅速发展, 电子元器件的集 成程度和组装密度不断提高, 在提供强大使用功能的 同时,也导致其工作功耗和发热量急剧增大.高温会 对电子元器件的稳定性、 可靠性和寿命产生有害的影 响,因此散热已成为微电子领域的一个重要问题,而 在热管理中起关键作用的是热界面材料(TIM).石墨 烯高导热性[1―4] 的发现迅速带动其在 TIM 中的应用, 且TIM 的导热率得到明显提高. Shahil 等在复合材料 中加入石墨烯, 由于石墨烯与基质的强偶联作用及其 高导热性使得复合材料的热导率大大增强[5―6] ;