n.二苯基
As the isocyan group is polymerized further, diphenyl carbondiimine may be formed, further polymerization of which forms a nitrogen-containing polycyclic aromatic compound. 异氰基化合物进一步二聚成二苯基碳化二亚胺，后者又聚合生成含氮杂环的多环芳烃。
