The Synthesis, Characterization And Properties Of Adipic Acid-1,4-Butanediol-urea Copolymer

A new degradable adipic acid-butanediol-urea copolymer wasprepared by melt condensation under argon environment with adipic acid,urea and1,4-butanediol as raw materials. The influence of reaction time,catalytic agent, the ratio of the raw material, urea content, and reactiontemperature to the properties were studied. Then, an adipic acid-1,4-butanediol-urea copolymer (polyester amide urea) with high molecularweights were synthesized used toluene diisocynate (TDI) as chain extender,which influenced the products’ molecular weight, thermal properties anddegradable properties. Adipic acid-1,4-butanediol-urea copolymer(polyester amide urea) film could be formed by casting and milling,respectively. The structure and properties of the copolymer werecharacterized by FT-IR,1H-NMR, GPC, TG, DSC and SEM, respectively.The research results show that with the best reaction condition ofmolar ratio on n(1,4-butanediol+urea): n(adipic acid)=1.16:1, n(1,4-butanedio):n(urea))=5:1,dibutyltin dilaurate as catalyst(0.03wt%), the highest temperature at220℃and reaction time between10hours, a product with weigh-averagemolecular weight of12700, desired color, better thermal stability and betterdegradability was obtained. With the increment of urea content, thedegradability, water absorbency and α-crystal increased while β-crystaldecreased, it is good for the improvement of degradable properties. Whenthe molar ratio of urea to alcohol was1:5, the degrade temperature ofpolyester amide urea was30℃higher than that of PBA. TDI extendedpolyester amide urea with high weigh-average molecular weight of11.3×104was obtained under the best chain extending condition: reaction for1~2hours at80℃, then raised the temperature to160℃for1hour in argonatmosphere. The polymer prepared by this method had better thermalstability and degradability than prepolymer. Besides, polyester amide ureafilms with better degradability were prepared by casting and millingformation reaction, the tensile strength of the milling film could reach19.33MPa with better pellucidity.