简介:【中文摘要】采用扫描隧道显微镜(STM)对射频等离子法制备的聚丙烯腈(PAN)基预氧化纤维的表面超微结构进行了研究,定性了预氧化纤维的三级结构单元。结果显示:在微米尺度下,预氧化纤维表面分布有粗细不一、沿轴向排列的带状微纤,微纤之间相互交简介:【中文摘要】采用扫描隧道显微镜(STM)对射频等离子法制备的聚丙烯腈(PAN)基预氧化纤维的表面超微结构进行了研究,定性了预氧化纤维的三级结构单元。结果显示:在微米尺度下,预氧化纤维表面分布有粗细不一、沿轴向排列的带状微纤,微纤之间相互交叉;在纳米尺度下,观察到微纤由相互缠结、紧密排列的超微纤组成,随着扫描范围的逐渐缩小,进一步看到超微纤由堆积起来的细小微晶组成;在原子级尺度上,微晶表面碳原子与高取向热解石墨(HOPG)相比不很规则,但具有取向排列趋势。
【英文摘要】 The ultrastructure of PAN-based preoxidized fibers prepared by a radio frequency plasma was investigated by scanning tunneling microscopy,and micrometer-,nanometer-and atom scale surface structural(units) in the preoxidized fibers were qualitatively defined.At the micrometer scale,microfibrils with different diameters and in strip-like form are aligned parallel to the fiber axis,and these microfibrils intersect each other.At the nanometer scale,the microfibrils are seen to be composed of closely packed and ...详细>