| Because of the excellent performance of citric acid esters product in the world,it has been used in many fields.andthe oversupply of citric acid in China is becoming increasingly serious.Therefore,Vigorously develop the application of citric acid esters is practical significance.Firstly,The thesis summarize the biodegradable elastomer and the plasticizer's application and the present world s production and the demand status,then had carried on the narration to the new non-toxic plasticizer TBC's nature research and the production status of domestic and foreign.Secondly,The Process for synthesis of tributyl citrate(TBC) by esterification of citric acid and n-butyl alcohol using a self-made solid acid as catalyst by microwave was studied.The optimum conditions of synthesis were determined as follows:the molar ration of butanol to citric acid was 4:1,the mass fraction of the catalyst was 3%,power of microwave irradiation was 500W, reaction time about 50min,Under such conditions.the yield of the product were up to 96.5%.Thirdly,Polyesters of citric acid and glycerol from different mole ratios of the reactants have been synthesized,The Polyesters insoluble in water and organic solvents. They have been characterised by their infrared spectroscopy, glass transition temperature and swelling behaviour. The acid to glycerol mole ratios 0.85 and 0.88 produce maximum cross-link density. Polyesters were amorphous,transparent and flexible.Glass transition temperatures (Tg) of Polyesters were all at 10℃.The hydrolytic degradation of the polymer film s in a buffer of pH value 7.4 at 37℃showed that polyesters had excellent degradability (all the films showed the weight losses more than 60% after 90h incubation). In addition,Polyesters was a new kind of antimicrobial material.Fourthly,The possible use of these polyesters as matrices for controlled release of drugs has been illustrated,The results show that the polyesters can control the drug re-leased.
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