| 摘要 |
PURPOSE:An aromatic polyester having melt moldability and an excellent balance between optical anisotropy and mechanical property, containing 2,7-dihydroxynaphthalene. CONSTITUTION:A mixture of p-acetoxybenzoic acid, a dihydroxynaphthalene diester such as dihydroxynaphthalene diacetate or dipropionate and 1,2-bis (phenoxy)ethane-4,4'-dicarboxylic acid or 1,2-bis(2-halophenoxy)ethane-4,4'-dicarboxylic acid is polycondensed by elimination of a monocarboxylic acid to obtain an aromatic polyester comprising structural units of formulas I -III (wherein the dioxynaphthalene include 2,7- and 2,6-dioxynaphthalenes and X is Cl or Br). In said aromatic polyester, units I amount to 0-85mol%, units II+III amount to 100-15mol%, the molar ratio of 2,7-dioxynaphthalene to 2,6-dioxynaphthalene in each of units II and III is 100/0-40/60, and the molar ratio, unit II/unit III, is 100/0-40/60.
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