| 摘要 |
Disclosed is a method for producing polyesters by means of esterification or re-esterification, precondensation of the esterified/re-esterified product, and polycondensation of the precondensed product at a pressure of 0.2 to 500 mbar and a temperature of 230 to 330 DEGREE C. According to said method, the vapors formed during precondensation and polycondensation are condensed and the obtained cooled diol is redirected into the condensation stage. In order to improve the degree of separation, the vapors are directed into a bottomless direct contact condenser, the base of which is immersed into the top funnel-shaped section of a barometrically dipped downpipe so as to form an annular space, cooled diol is sprayed into the vapors in the top section of the direct contact condenser, the remaining vapors are recovered via the annular space, and the formed polymer aggregates are removed.
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