Device and technology for synthesis of aromatic polyester polyol

Abstract

The invention discloses a device and technology for synthesis of aromatic polyester polyol. The device for the synthesis of the aromatic polyester polyol comprises a mixer, a polyol intermediate tank,an esterification reaction kettle, a polycondensation reaction kettle, a blending reaction kettle, a polyol recovery tower and the like. The technology of the synthesis of aromatic polyester polyolcomprises the following steps: preheating organic polycarboxylic acid to a certain temperature, mixing the preheated organic polycarboxylic acid with polyhydric alcohol under a certain temperature inthe mixer to obtain a mixture, and enabling the obtained mixture to sequentially pass through the esterification reaction kettle, the polycondensation reaction kettle and the blending reaction kettlefor reactions, so as to obtain polyester polyol products with different specifications; and enabling gaseous phases in the esterification reaction kettle and the polycondensation reaction kettle to enter the polyol recovery tower, and enabling the collected polyhydric alcohol to enter the polyol intermediate tank for recycling. Compared with a conventional intermittent multi-kettle type reaction technology, the method disclosed by the invention has the advantages that the technology technique parameters of three stages of esterification, polycondensation and blending are reasonably controlled,so that the adjustable ranges (average molecular weight, carboxy value and hydroxyl value and the like) of performance specifications of products are wide, the polyhydric alcohol recovery efficiencyis high, the loss is low, the reaction efficiency of an esterification reaction course and the reaction efficiency of a polycondensation course are effectively improved, the same performance index asthat in foreign countries is achieved, and the consumption of raw materials of the products is reduced.

Description

technical field [0001] The invention relates to a device and process for synthesizing polyester polyols, in particular to the synthesis process technology of aromatic polyester polyols, and belongs to the technical field of polyester polyols. Background technique [0002] Polyester polyols are usually a type of hydroxyl-terminated polyester formed by esterification and polycondensation of polyols and organic dicarboxylic acids (anhydrides) or polymerization of polyols and lactones, with an average molecular weight of 1000-4000 and carboxyl groups The concentration shall not exceed 0.02mol•kg. Polyester polyols are mainly used as raw materials for polyurethane synthesis. Compared with polyether polyols, they have better wear resistance, oil resistance and temperature resistance, and higher mechanical strength. According to the use of different dicarboxylic acids, it can usually be divided into aliphatic polyester polyols, aromatic polyester polyols and mixed acid polyester p...

AI Technical Summary

Problems solved by technology

However, the current batch stirred tank reaction technology does not consider the characteristics of different reaction stages. The two-stage reactions usually occur simultaneously in one or more reactors, resulting in polyol loss, high energy consumption in the process, and poor specifications of polyester polyol products. And other issues

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