文献类型：期刊文献

中文题名：聚酰亚胺辅助制备高定向石墨烯基全炭泡沫及其在导热聚合物复合材料中的应用

英文题名：Polyimide-assisted fabrication of highly oriented graphene-based all-carbon foams for increasing the thermal conductivity of polymer composites

作者：熊科[1];孙智鹏[1];胡吉辰[1];马成[1];王际童[1];葛翔[2];乔文明[1];凌立成[1]

机构：[1]华东理工大学化学工程联合国家重点实验室,上海200237;[2]常州富烯科技股份有限公司,江苏常州213144

年份：2024

卷号：39

期号：2

起止页码：271

中文期刊名：新型炭材料（中英文）

外文期刊名：New Carbon Materials

收录：CSTPCD;;EI(收录号：20241515900605);Scopus;北大核心:【北大核心2023】；CSCD:【CSCD2023_2024】；

基金：国家自然科学基金(22178107,U21A2060,22178116,21978097);新疆维吾尔自治区重点研发计划(2022B01030);上海市浦江计划(21PJD019).

语种：中文

中文关键词：石墨烯膜;二次利用;热导率;各向异性泡沫;热界面材料

外文关键词：Graphene film;Reutilization;Thermal conductivity;Anisotropic foam;Thermal interface materials

摘要：石墨烯及其衍生物具有高纵横比的二维层状结构,在加工过程中通常倾向于水平排列。因此,石墨烯基复合热界面材料虽然具有较高的面内热导率,但其表现出的低面外热导率难以满足实际应用需求。本文通过定向冷冻策略制备了竖直排列的聚酰亚胺/石墨纳米片(PG)导热骨架以提高聚合物复合材料的面外热导率,其中石墨纳米片(GNs)为高导热石墨烯薄膜的粉体边角料。在该过程中,采用水溶性聚酰胺盐溶液直接分散疏水的GNs,热亚胺化后获得的聚酰亚胺在辅助GNs定向排列的同时经石墨化处理转变为人造石墨。同时,GNs的引入提高了PG骨架的有序度和密度,进一步提高了聚二甲基硅氧烷(PDMS)基复合材料的强度和导热性能。结果表明,所制备的PDMS/PG复合材料(PG:21.1%)的面外热导率达14.56 W·m^(?1)·K^(?1),是纯PDMS的81倍。这种简便的聚酰亚胺辅助二维疏水填料定向排列的方法为各向异性热界面材料的规模制备提供了思路,同时实现了石墨烯薄膜边角料的再利用。
Graphene and its derivatives are often preferentially oriented horizontally during processing because of their two-dimensional(2D)layer structure.As a result,thermal interface materials(TIMs)composed of a polymer matrix and graphene-derived fillers often have a high in-plane(IP)thermal conductivity(K),however,the low through-plane(TP)K makes them unsuitable for practical use.We report the development of high-quality polyimide/graphite nanosheets(PG)perpendicular to the plane using a directional freezing technique that increase the TP K of polymer-based composites.Graphene-derived nanosheets(GNs)were obtained by the crushing of scraps of highly thermally conductive graphene films.A water-soluble polyamic acid salt solution was used to disperse the hydrophobic GNs filler to achieve directional freezing.The polyimide,which facilitated the directional alignment of the GNs,was then graphitized.The introduction of the GNs increases the order and density of the PG,thus improving the strength and heat transfer performance of its polydimethylsiloxane(PDMS)composite.The obtained PG/PDMS composite(21.1%PG,mass fraction)has an impressive TP K of14.56 W·m^(?1)·K^(?1),81 times that of pure PDMS.This simple polyimide-assisted 2D hydrophobic fillers alignment method provides ideas for the widespread fabrication of anisotropic TIMs and enables the reuse of scraps of graphene films.