尼龙6/可膨胀石墨/Al_2O_3导热绝缘复合材料的制备与性能  

Preparation of Thermally Conductive,Electrically Insulating Polyamide 6 Composite with a Hybrid Network of Alumina and Low Temperature Expandable Graphite and Its Properties

作　　者：李瑶[1] 陈洋[1] 邹华维[1] 梁梅[1] Yao Li, Yang Chen, Huawei Zou, Mei Liang(Polymer Research Institute of Sichuan University, State Key Laboratory . of Polymer Materials Engineering, Chengdu 610065, China)

机构地区：[1]四川大学高分子研究所高分子材料工程国家重点实验室,四川成都610065

出　　处：《高分子材料科学与工程》2018年第9期120-125,共6页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51703137)

摘　　要：低温可膨胀石墨(LTEG)呈二维片层状,具有优良的导热导电性,可以作为导热填料提高高分子材料的导热性能。文中将Al_2O_3与LTEG复配,与尼龙6(PA6)树脂复合,制备了导热复合材料。实验控制LTEG的用量低于其导电逾渗阈值,保证最终材料的体积电阻率在较高水平。熔融挤出过程中,LTEG原位膨胀、剥离形成石墨微片,石墨微片起到"桥梁"作用,与Al_2O_3粒子相互搭接,促进导热通路的形成,明显提高了材料的热导率。试样EA5/60 (5%LTEG+60%Al_2O_3)的热导率达到2. 019 W/(m·K),比纯PA6热导率提高了596. 2%。引入石墨微片使复合材料的体积电阻率降低2~3个数量级,保持在10^(12)~10^(13)Ω·cm。Two-dimensional low temperature expandable graphite （LTEG） has outstanding electrical and thermal properties, and can be used to enhance thermal conductivity of polymer composites. A1203 and two-dimensi0nal LTEG were added into polyamide6 （PA6） resin to prepare composites with improved thermal conductivity and electrical insulation via the in-situ exfoliation of LTEG during a melt blending process. An optimal proportion of LTEG was used as part of the thermally conductive fillers to guarantee electrical insulation. LTEG flakes act as bridges between A1203 and promote thermally-conductive pathways, hence a higher thermal conductivity. The composite containing 5% of LTEG and 60 % of A1203 reaches the thermal conductivity of 2.019 W/（m＂ K）, which is 5961296 higher than that of the virgin PA6. Althoughincorp0rating LTEG deteriorates volume resistivity, decreasing by 2--3 orders of magnitude compared with that ofPA6 resin, and the volume resistivity reveals that the resultant composites still exhibit high volume resistivity, which is in the range of 1012 to 1013 ∩ cm.

关 键 词：尼龙6 可膨胀石墨 氧化铝 导热性能 电绝缘 

分 类 号：TQ323.6[化学工程—合成树脂塑料工业]