Maleic Anhydride → HCID 21326706, compound

Participants

Reaction Steps

A solution of 768 g (7.83 mol) of maleic anhydride (MA) in 1059 g (11.75 mol) of 1,4-butanediol was placed in the first reactor of a reactor cascade made of acid-resistant material, which cascade comprised 3 reactors connected in series each having a volume of 5 l and each being provided with a high-speed stirring system of conventional construction (turbine stirrer, speed: 800-1200/min) and a distillation column (10 theoretical plates), the solution was quickly heated while stirring to a reaction temperature of 105°-100° C. and the water of reaction which formed was distilled off. After a reaction time of 6 hours, the reaction mixture was transferred into the connected second reactor; there a further part of the water of reaction was distilled off at a reaction temperature of 110°-115° C. while stirring. After a reaction time of 4 hours, the reaction mixture was finally transferred into the connected third reactor; there the remainder of the water of reaction was removed under a pressure of 400 mbar and at a reaction temperature which was gradually increased from 115° to 125° C. After a further 2 hours (total of 12 hours), the esterification was ended. The oligomeric 1,4-butanediyl maleate obtained (1682 g) had a mean degree of oligomerization of n=3 (measured by gel permeation chromatography) and an acid number of 21 mg KOH/g of reaction mixture.

Provenance & Evidence