| 摘要 |
Mixtures of 50 to 90 mole-% terephthalic acid dialklesters and 10 to 50 mole-% 4,4'-diphenyldicarboxylic acid dialkylesters whose alkyl grps. may contain up to 4C-atoms, are transesterified, in presence of a catalyst, with 2 to 2.4 times the molar amount of a mixture comprising 50 to 90 mole-% of an aliphatic diol with 2 or 3C-atoms and 10 to 50 mole-% 1,4-dimethylolcyclohexane, at 160- to 210 degrees C, and the transesterification product is then polycondensed at 260 to 350 degrees C in known manner. The mixture pref. comprises 60 mole-% dimethyl terephthalate and 40 mole-% 4,4'-diphenyldicarboxylic acid dimethyl ester with 70 mole-% ethylene glycol and 30 mole-% 1,4-dimethylolcyclohexane. The products hav e freezing temps. between 100 and 130 degrees C, and are suitable for manufacture of amorphous mouldings which are resistant to relatively high temperatures. |
