摘要 |
In a process of producing PBT, a mixture of BDO and TPA is esterified in the presence of a catalyst solution, and the esterification product is polycondensated. To avoid the formation of deposits in the PBT, the catalyst solution contains 0.05 to 10 wt-% alkyl titanate, 85 to 99 wt-% BDO, 50 to 50,000 ppm bifunctional carboxylic acid equivalents and/or monofunctional hydroxycarboxylic acid equivalents and not more than 0.5 wt-% water.
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