• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.40-44
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• 2014

For the purpose of development of an effective process for purified CHMI particles, a series of experimental researches on the synthesis of CHMI from CHMAIE, purification and precipitation of CHMI were preformed. It is turned out that n-heptane reflux imidation is more beneficial than toluene put-out imidation not only to the synthesis but to the precipitation of CHMI. By washing the synthetic CHMI with cold n-heptane twice, purified CHMI with 99.7% purity could be obtained at the cost of 11.7% weight loss. And CMHI particles were effectively prepared by spouting molten CHMI through the spiral nozzle with 3 mm diameter under the pressure of $1.5{\sim}2.0kg/cm^2$.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.226-229
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• 2020

N-phenylmaleimide (PMI), a compound for strengthening the heat resistance of ABS resin, is a yellow crystal. Therefore, copolymers modified with PMI exhibit color, which limits their use. In order to overcome such disadvantage, the demand for N-cyclohexylmaleimide (CHMI), which has similar properties to PMI and also is a white crystal, is increasing. However, CHMI is difficult to industrialize due to the formation of various by-products during synthesis, which requires an additional purification process resulting in a low yield. In this study, composite catalysts were developed to improve these problems and industrially produce CHMI. Finally, CHMI was synthesized with a 85% yield and at least 99.5% purity.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.545-549
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• 2013

For the purpose of development of effective synthetic process of CHMI, a series of experiments were preformed on the preparation of CHMAIE, the intermediate of CHMI. For the first step, CHMA was synthesized by dropwise mixing of cyclohexylamine with maleic anhydride in toluene and 98.2% of theoretical CHMA was obtained by precipitation at $10^{\circ}C$ for 2 hours. The optimum reaction temperature of the esterfication, preparation reaction of CHAMIE from CHMA, was $68^{\circ}C$, and equilibrium conversion at optimum temperature was 98.5%. Equilibrium reaction time decreased with reaction temperature, and 4 hours was taken to reach equilibrium at optimum reaction temperature. Toluene in the final reaction product could be recovered by vacuum distillation. The recovery of toluene was increased with distillation temperature and 98% of toluene could be recovered at $55^{\circ}C$.