| 摘要 |
Aromatic copolyamides, soluble in organic polyamide solvents, comprise at least 95 mol % of the recurrent structural units of the formulae OCArCO A HNAr'NH B <IMAGE> C <IMAGE> D and up to 5 mol % of structural units containing m-bonds. -Ar- and -Ar'- are here divalent, unsubstituted or substituted aromatic radicals, the valency bonds of which are in the para-position or in a comparable coaxial or parallel position, and -R and -R' are different from one another and are lower alkyl radicals or lower alkoxy radicals.
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