PI/石墨微片半导电复合薄膜的制备与表征

Synthesis and Characteristics of Polyimide/Graphite Microchip Semiconductor Composite Film

通过乙醇超声处理膨胀石墨的方法制备石墨微片,并用原位聚合法制备聚酰亚胺/石墨微片复合薄膜;探讨了复合薄膜的结构、微观形态;讨论了石墨微片的含量对复合薄膜的体积电阻率、表面电阻率、力学性能以及热稳定性的影响。结果表明,石墨微片能够在聚酰亚胺基体中均匀分布,并对复合薄膜亚胺化过程没有影响,复合薄膜亚胺化完全。复合薄膜较纯膜力学性能有所下降,热稳定性提高,在石墨微片质量分数为4%时,达到渗滤阈值,体积电阻率和表面电阻率均可下降到108数量级,达到半导电复合薄膜的要求。

The polyimide/graphite microchip composite film was prepared by insitu polymerization,and the graphite microchip was prepared by ethanol sonicating the expanded graphite.The structure and micromorphology of the composite film were characterized.Effects of graphite microchip amount on the surface resistivity,volume resistivity,the mechanical properties and the thermal performance were discussed.The results showed that graphite microchip can be uniformly distributed in the polyimide matrix and the imidization was complete.Mechanical properties of composite film were decreased but the thermal stability was improved,compared with pure film.When mass content of the graphite microchip was 4 wt%, percolation threshold was reached.The surface resistivity and the volume resistivity of the composite film could be down to 10^8Ω,which met the requirements of the semiconductor composite film.