Method 1: Take isononanoic acid and isononanol as raw material, use acid catalyst or metal catalyst, but due to the activity problem of isononanoic acid and isononanol, through the direct reaction of isononanoic acid ester and isononanol, isononanoic acid and isononanol can not be fully reacted, which brings difficulties to the subsequent purification. Isononanoic acid and isononanol residue in the final product will affect the product performance and shorten the shelf life of the product.
Method 2: In order to make isononanoic acid and isononanol react completely, the organic substance toluene or cyclohexane is used as a water-carrying agent to synthesize isononyl isononanoate by esterification reaction. However, when toluene or cyclohexane is used as the water-carrying agent, toluene or cyclohexane may remain in the isononyl isononanoate after the esterification reaction and increase the subsequent purification step, and if toluene or cyclohexane remains in the final product, the product's application in cosmetics may be hazardous to humans.
Method 3: using isononanoic acid and ethanol as raw materials, using acid as a catalyst, carrying out an esterification reaction to synthesize ethyl isononanoate, adding isononanoic acid alcohol to carry out an ester-exchange reaction, and then adding an alkali neutralizer, washing with water, and carrying out a reduced-pressure distillation to obtain isonononyl isononanoate. Compared with the prior art, the preparation method of ethyl isononanoate described is simple and easy to operate, reduces the use of organic water-carrying agent toluene or cyclohexane, is environmentally friendly, and can obtain isononyl isononanoate of higher quality.
