【摘要】 研究聚酰亚胺(PI)薄膜在1 000℃炭化不同时间获得的炭膜的结构与性能,并利用XRD、Raman、TEM等测试手段对其进行表征。结果表明,随着炭化时间的延长,XRD中2θ衍射角先增大后减小,在炭化9 h时达到最大,即最接近单晶石墨的衍射峰26°。ID/IG的变化规律与之一致,随着时间延长先增大后减小。这可能是由于随着时间的延长,炭化程度增加,炭膜中石墨碎晶成分增加,ID/IG增加。继续延长炭化时间,炭膜中石墨碎晶趋向于完整排列,ID/IG减小。炭膜的电导率也相应先增加后减小,在炭化9 h时达到最大。这与XRD和Laman的表征结果一致。更多还原

【Abstract】 The changes of structure and its effect on the performance of polyimide films were studied at high carbonization temperature in Ar atmosphere. The microstructures of carbon films at different carbonization time ranging from 1~17 h were investigated by XRD and Raman. The influence of carbonization time on the electrical conductivity of the samples was also studied. The results show that with the extension of carbonation time, XRD in 2θ diffraction angle increased, then stabilized or even decreased. The result show that with increasing of carbonization time between 1 h and 17 h, 2θ angle of the sample increases at first and then decreases, which reaches maximum at 9 h and is closest to the graphite crystal diffraction peak of 26°. ID/IGshows a similar tend of first increase and then decrease. This may be because that, with the prolongation of carbonization time, both the carbonization degree and graphite microcrystallites composition increase, resulting in bigger ID/ IG. As the carbonation time continues to extend, graphite microcrystallites of carbon films tend to be well-defined structure and arrange regularly, and ID/ IGdecreases. Electrical resistivity of carbon films becomes bigger firstly and then smaller, reaching maximum value at 9 h. This is consistent with the characterization results of XRD and Raman.更多还原