Method for producing light stabilizer sebacic acid (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) diester

Abstract

The invention discloses a method for producing a light stabilizer sebacic acid (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) diester. In the method, dimethyl sebacate, 1, 2, 2, 6, 6-pentamethyl-4-hydroxypiperidines serves as the raw material and reaction is carried out in the presence of solvent and catalyst at certain temperature to obtain sebacic acid (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) diester. In the invention, the dimethyl sebacate, 1, 2, 2, 6, 6-pentamethyl-4-hydroxypiperidines serve as raw materials for synthesizing sebacic acid (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) diester, active carbon loaded tetraisopropyl titanate catalyst is employed; as a result, separation and purification process is simplified, the reaction time is short, product yield is more than 97%, the catalyst can be repeatedly used; in addition, the method of the invention features high purity of obtained product, reduced energy consumption, little environmental pollution, low cost, thus being an ideal technology for industrialized production.

Description

Technical field: [0001] The invention relates to a production method of a light stabilizer sebacic acid bis(1,2,2,6,6-pentamethyl-4-piperidinyl) ester. Background technique: [0002] Di(1,2,2,6,6-pentamethyl-4-hydroxypiperidinyl) sebacate is a hindered amine light stabilizer with low molecular weight, low alkalinity, high efficiency and low toxicity, which can prolong various The use time of plastics and coatings exposed to outdoor exposure. During use and processing, it will not produce odor with polymers, nor will it affect the original color of the material, and the product is not easy to volatilize during high-temperature processing. It has good miscibility with most industrial solvents and has excellent polymer compatibility. This product is a light stabilizer for paints and inks. It can be used in acrylic and polyurethane paints to effectively prevent foaming and surface peeling of the coating under exposure. It can also be used In latex paint, alkyd paint, epoxy pai...

AI Technical Summary

Problems solved by technology

[0007] At present, there are very few domestically published research reports on the synthetic method of di(1,2,2,6,6-pentamethyl-4-hydroxypiperidinyl) sebacate catalyzed by activated carbon supported tetraisopropyl titanate. In China, only the light stabilizer UV-292 [bis(1,2,2,6,6-pentamethylpiperidinol) sebacate and mono(1,2,2,6,6-pentamethyl The mixture of piperidinol) methyl sebacate] reported that bis(1,2,2,6,6-pentamethylpiperidinol) sebacate and mono(1,2 , 2,6,6-pentamethylpiperidinol) the mixture of methyl sebacate is darker in color, the reaction temperature is high, and the post-treatment process is more complicated, so it is not suitable for industrialized production

According to literature reports, adopting Lewis acid, alkali etc. as catalyst to carry out transesterification reaction, catalyst is easy to corrode equipment, the pollution that post-processing produces is big, and product quality is poor

A solid acid catalyst is used to catalyze the transesterification reaction. Although the product and the catalyst are easily separated, the corrosion to the equipment is small, and the catalyst can be recycled, but the selectivity and activity are low.

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