Sebacic acid CAS 111-20-6

Most of the sebacic acid diester series products are used as low-temperature plasticizers in the plastics industry and the synthetic rubber industry. The two main products are dibutyl sebacate and di-n-hexyl sebacate. Dibutyl sebacate is a colorless and transparent liquid with fruit aroma and light oily odor. It is compatible with most resins and synthetic rubbers, so it can be used as the main plasticizer to make the product have excellent low temperature performance and oil resistance. . Dibutyl sebacate is non-toxic and has cold resistance. It has a wide range of applications in the food packaging material industry and synthetic fragrance industries. In addition, it can also be used as a solvent for some rubbers and resins. The traditional method for synthesizing dibutyl sebacate is to synthesize by esterification of sebacic acid and n-butanol under the catalysis of concentrated sulfuric acid. This method has disadvantages such as easy corrosion of equipment, long production process, unsatisfactory yield and purity. In recent years, many domestic scientific researchers have devoted themselves to developing new catalysts to replace concentrated sulfuric acid to catalyze the production of dibutyl sebacate. In recent years, using granular activated carbon-supported silicotungstic acid as catalyst, the optimal reaction conditions for the synthesis of butylene sebacate by orthogonal experiments are that the molar ratio of acid to alcohol is 1:3.5, and the amount of supported catalyst is the mass of sebacic acid. The final esterification rate of this method is 98.79%; the activated carbon-supported phosphotungstic acid is used as the catalyst, the molar ratio of acid to alcohol is 1:5, the amount of sebacic acid is 0.08mol, and the amount of catalyst is 0.08mol. 1.5g (solid load 25.3%), reaction time 3h, cyclohexane with water agent 10ml, reaction temperature 98-112℃ to synthesize dibutyl sebacate, the esterification rate reaches 98.1%; Ester is a non-toxic cold-resistant plasticizer with low volatility and low viscosity. It can be used as a plasticizer for agricultural films, wires, sheets, artificial leather, outdoor water pipes, frozen foods, and pharmaceutical packaging plastics. And because of its low viscosity, di-n-hexyl sebacate can also be used as a lubricant.

The traditional synthesis method of di-n-hexyl sebacate also uses sulfuric acid as catalyst. Using solid acid SO42-/TiO2-ZrO2 as catalyst, it was studied under the reaction conditions of reaction temperature of 220℃, reaction time of 2.5h, molar ratio of acid to alcohol 1:.3.25, and catalyst dosage of 0.8% of the total mass of the system. The yield of di-n-hexyl sebacate can reach the highest 98.41%. In addition, the synthesis of dihexyl sebacate was studied using silicotungstic heteropolyacid and activated carbon supported p-toluenesulfonic acid as catalysts, respectively. The optimal reaction conditions for the former synthesis of dihexyl sebacate were determined by orthogonal experiments: the amount of sebacic acid was 0.05mol, the molar ratio of acid to alcohol was 1:2.6, the catalyst was 0.5g, and the water agent toluene was 10ml, and the reaction time was 1h, the average esterification rate is 95.3%; the best reaction conditions for the latter are: the dosage of sebacic acid is 0.05mol, the dosage of n-hexanol is 0.13mol, the dosage of catalyst is 3g, the toluene with water agent is 15ml, and the reaction time is 1h. The average esterification rate under 98.2%.

Diethyl sebacate is a colorless and transparent liquid with fruit flavor. Its main purpose is to be used as food flavoring. In order to solve the defects of the traditional catalytic synthesis with concentrated sulfuric acid, the catalytic synthesis of diethyl sebacate by p-toluenesulfonic acid was studied. : 8:0.31, cyclohexane is a water-carrying agent, and the water is refluxed for 1 h. Under the reaction conditions, the ester yield reaches 96.9%. This method has the advantages of convenient operation, mild reaction, high product purity and yield; The acid cation exchange resin was used as the catalyst, and the optimal reaction conditions explored were that the molar ratio of acid to alcohol was 1:7, the amount of catalyst was 1.5g, and the amount of cyclohexane with water agent was 15ml (when the amount of sebacic acid was 0.1mol), Reaction at 80℃ for 7h, the esterification rate can reach 95.45%; gold nanocomposite solid superacid S2O82-/CoFe2O4 is prepared. The optimal reaction conditions of the catalyst are that the molar ratio of acid to alcohol is 1:4, sebacic acid is 0.1mol, The catalyst was 1.0g, the reaction time was 2.5h, and the esterification rate was 93.6% under this reaction condition.

Foreign researches related to the catalytic synthesis of diethyl sebacate also include research on titanium dioxide solid acid catalyst, which is made by impregnating powdered titanium dioxide in sulfuric acid solution. Catalytic performance in the esterification reaction of acid and ethanol, using this catalyst to participate in the esterification reaction of sebacic acid and ethanol, it will reach the reaction equilibrium point in about 80min.

Plastic products are one of the indispensable products in daily life. They are easy to process, light, and beautiful. With the improvement of the quality of life, plastic products are increasingly showing their irreplaceable status, but the problem of environmental pollution caused by waste plastics is also becoming more and more serious. Therefore, the development of materials to replace traditional plastics is also one of the important topics of contemporary environmental protection. Biodegradable aliphatic polyesters are ideal substitutes for traditional plastics. Using sebacic acid and hexanediol as raw materials and decalin as solvent for direct polymerization, degradable high molecular weight polyhexanediol sebacate was synthesized with a yield of 96%, and its melting point was determined to be 76.5 ℃, The crystallization temperature was 56°C.

After testing, polyhexylene sebacate has excellent mechanical properties, high strength and toughness, and can be used instead of traditional plastics. Biodegradable polyester materials also have a range of elastic aliphatic polyesters. This series of polyesters is prepared by a two-step reaction using sebacic acid, ethylene glycol and glycerol as raw materials. That is, sebacic acid and ethylene glycol are used to synthesize a prepolymer, and then the prepolymer and glycerin are mixed and reacted according to different ratios. The final product is a transparent polyester, which is tough, insoluble in organic solutions, and has a hydrophilic surface. At 37℃, the enzymatic degradation study was carried out with porcine pancreatic enzyme in phosphate buffer solution. The results showed that the enzymatic degradation degree of this series of polyesters increased with the increase of glycerol content. It is worth mentioning that the -COOC- group on the surface of the polyester is the decisive factor for the enzymatic degradation ability. In addition to biodegradable polyester materials, the synthetic green lubricant oleic acid neopentyl glycol sebacate mixed ester is prominent. The mixed ester is obtained by first synthesizing oligomers with sebacic acid and neopentyl glycol as raw materials, and then esterifying the oligomers with oleic acid. After testing, the mixed ester of oleic neopentyl glycol sebacate has good viscosity and thermal stability, and at the same time has good biodegradability, and can be used as a material to replace traditional mineral oil lubricants.

Sebacic acid is also widely used in medical synthetic chemistry. Aiming at the defect of strong hydrophobicity when polysebacic anhydride alone is used as a drug carrier for sustained and controlled drug release, a polysebacic anhydride-polyethylene glycol copolymer was synthesized from sebacic acid, acetic anhydride and PEG. In the copolymer, polyether PEG with oil-water amphiphilicity is introduced into the main chain of polysebacic anhydride, in order to achieve the purpose of improving the strong hydrophobicity of polysebacic anhydride. Through the determination of solubility, it was confirmed that the introduction of PEG indeed improved the solubility of the copolymer in polar solvents.