Study On Synthesis And Application Of Adipate Dihydroxy Higher Alcohols Ester By Transesterfication

Adipate dihydroxy higher alcohols has the feature of long straight alkali carbon chain and two ester groups in the molecular constitution. It can be used as the plasticizer of cold tolerance in the polymer materials, such as plastics and rubbers and so on. And it can be used as diesel pour point depressant. So the research of synthesis and application on adipate dihydroxy higher alcohols has high potential value in practice.For the nature of high-melting point, high boiling point and decomposition reaction and leakingout as side reactions in the high temperature of adipic acid and C₁₂～C₁₈ alcohols, so until now there is still no reports of synthetizing adipate dihydroxy higher alcohols in domestic and abroad by direct esterification.This thesis discussed the possibility of synthesizing the adipate dihydroxy higher alcohols by transesterfication when dimethyl adipate and C₁₂～C₁₈ alcohols were used as raw materials with butyl titanate and sodium methylate as catalysts. The influencing factors of the molar rate of raw-materials, amount of catalysts, and reaction temperature were discussed in detail. The conditions which are adapted for transesterfications were identified. When the molar rate of C₁₂～C₁₈ and dimethyl adipate was 2.1, 2.2, 2.3 and 2.2, the conversion of reaction was 96.85%, 91.31%, 88.53% and 82.47% with butyl titanate used as catalyst which the amounts were 0.3%, 0.3%, 0.25% and 0.35%. When the molar rate of C₁₂～C₁₈ and dimethyl adipate was 2.1, 2.2, 2.25 and 2.3, the conversion of reaction was 94.04%, 90.57%, 84.76% and 85.02% with sodium methylate used as catalyst which the amounts were 2.5%, 2.5%, 2.6% and 2.5%. The result showed that butyl titanate is better than sodium methylate.Base on the experiments, this research studied on the dynamics of transesterfication between dimethyl adipate and C₁₂～C₁₈ alcohols. It is proved that the reaction of transesterfication between dimethyl adipate and C₁₂～C₁₈ alcohols was second order reaction. And the equation of reaction rate of transesterfication between dimethyl adipate and n-Dodecanol is From the results of the research, the adipate dihydroxy higher alcohols which is got by experiments were good plasticizers of cold tolerance. The ability of plasticizer of didodecyl adipate was much better than dioctyl adipate which is wide used right now. Adipate dihydroxy higher alcohols also can be used as pour point depressant. On the amount of ditetradecyl adipate was 0.3%, solidification point of diesel 0^# dropped 11℃and cold filter plugging point of 0^# diesel dropped 8℃...