A polybenzimidazole having a polymer chain with the following repeating unit: ##STR1## R.sub.2 is a divalent carbon ring with the linkage to an adjacent repeating unit through adjacent carbon atoms of the ring. Such polybenzimidazoles are formed by the condensation of (a) a substitute carbon ring compound, having at least one dicarboxylic anhydride or its equivalent substituted at adjacent carbon atoms and (b) an organic tetraamine of the following formula: ##STR2## Polybenzimidazoles of the foregoing type may be formed by the use of a tetracarboxylic dianhydride in the condensation reaction. These cross-linked polymers are characterized by minimal softening or burning at high temperature.
一种聚
苯并咪唑,其聚合物链具有以下重复单元:##STR1## R.sub.2是具有连接到环相邻碳原子的相邻重复单元的二价碳环。这种聚
苯并咪唑是由以下化合物的缩合而成:(a)一种取代碳环化合物,其在相邻碳原子上具有至少一个二
羧酸酐或其等效物,以及(b)以下公式的有机四胺:##STR2## 上述类型的聚
苯并咪唑可以通过在缩合反应中使用四
羧酸二酐来形成。这些交联聚合物的特点是在高温下具有最小的软化或燃烧。