【摘要】 通过两步法以苯均四酸二酐和芳香二胺单体合成了芳香环状聚酰亚胺,并且用基质辅助激光解吸电离飞行时间质谱技术对其结构进行表征。以1,8,9-蒽三酚为基质,二甲基甲酰胺为溶剂,正离子方式记录谱图,谱图中可以观测到环状齐聚物的氢、钠、钾三组加合分子离子峰。质谱数据表明:环状聚酰胺酸室温放置时,部分三聚体转化为二聚体,可提高环状二聚体的收率。更多还原

【Abstract】 Aromatic cyclic oligoimides were synthesized by pyromellitic dianhydride and p,p’-oxydianline or p,p’-methylenedianline using two steps approach.Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS) was used for analyzing their structures.The samples were dissolved in dimethyl formamide(DMF).The 1,8,9-dithranol as the matrix and the data was recorded by positive ion mode.The adducts of hydrogen,sodium and potassium of cyclic oligomers were measured and the mass spectrometry data revealed that partial trimeric cyclic converts to dimeric cyclic after a long time at room temperature for cyclic oligoimide,so the yield of dimer is enhanced.更多还原