2873-97-4Relevant articles and documents
A high-purity diacetone acrylamide preparation method
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Paragraph 0024-0041, (2019/02/13)
The invention discloses a high-purity diacetone acrylamide of the preparation method, the steps of the method are as follows: 1, acrylonitrile and diacetone alcohol in concentrated sulfuric acid under the catalysis of the one-step synthesis reaction, the crude product obtained diacetone acrylamide; 2, the diacetone acrylamide [...] alkali hydrolysis, removing high melting point acrylic amide; 3, hydrolysis is performed after fractionation, get colorless transparent molten shape liquid; 4, a molten shape liquid into the recrystallization in xylene, petroleum ether washing replacement xylene, drying, high purity diacetone acrylamide. The method is simple and environmental protection, not only yield as high as 80% or more, and the resulting diacetone acrylamide high purity, the purity of 99.5% or more.
Preparation method of diacetone acrylamide
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Paragraph 0018; 0022-0027, (2018/02/03)
The invention discloses a preparation method of diacetone acrylamide. The preparation method comprises the following steps: (1) acetone and propenenitrile are mixed and are added to concentrated sulfuric acid, acetone and propenenitrile and concentrated sulfuric acid undergo condensation reaction fully, and after the reaction is finished, a mixture is obtained; (2) the mixture is washed with a dispersing agent, after the washing is finished, solid-liquid separation is carried out, and an intermediate product is obtained; (3) the intermediate product is mixed in an organic solvent, then alkali is added, alkali and the intermediate product react in a liquid phase system, the reaction is finished when a ph value of the liquid phase system is greater than or equal to 7, and after the reaction is finished, the organic solvent in which products are dissolved is separated out, and a product solution is obtained; and (4) a polymerization inhibitor is added to the product solution, reduced pressure distillation is carried out for recovering the organic solvent, then rectification is carried out, and a fraction obtained through the rectification is diacetone acrylamide. According to the preparation method, an intermediate of diacetone acrylamide is separated out, the impurities like acrylamide and vinyl monomers can be removed, the impurity content in subsequent separation steps is few, and the content of diacetone acrylamide can be raised.
Stepwise Execution of Exothermic Reactions with Participation of Carbocations
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Page/Page column 2, (2009/01/20)
The invention relates to a method for carrying out reactions with participation of carbocations, whereby the initial most strongly exothermic phase of the reaction is carried out at high temperature (60 to 120° C.) and short residence time (1 to 30 seconds) in a microreactor and the subsequent less exothermic phases are carried out at optionally lower temperatures in two or more residence time units with longer residence times (1 to 30 seconds).