β-环糊精与EPA包结物的制备及包结物热分解动力学研究

THE PREPARATION OF INCLUSION COMPOUND OF Β- CYCLODEXTRIN WITH EICOSAPENTAENOIC ACID (EPA) AND IT'S PROPERTY OF THE THERMAL DECOMPOSITION KINETICS

采用竞争包结法,用紫外＿可见光谱研究了在pH=10 5的缓冲液中β＿环糊精与EPA包结物的制备,结果表明,1分子EPA与2 5分子β＿环糊精依据范德华作用力和疏水作用力发生包结作用,生成稳定的包结物.包结物适宜的制备条件为:β＿环糊精与EPA的摩尔比为2 5∶1,主客体溶液的浓度比为14 0∶1,包结温度25℃,反应时间2 8h.用非等温热重法研究了β＿环糊精与EPA包结物的热分解反应动力学,实验结果显示,β＿环糊精与EPA包结物热分解过程反应级数大于1,用Ozawa(I)法和Reich法求得的热分解反应的活化能分别为183 85kJ/mol和183

Spectrophotometrictitration were performed in aqueous buffer solution (pH=10.5) to determine the binding constants of β_Cyclodextrin(β_CD) with Eicosapentaenoic Acid (EPA), a kind of guest molecules, using phenolphthalein as a spectral probe. The results indicated that 2.5 moles of β_CD could include one mole EPA to form inclusion compound by means of several weak interaction and force, Van Der Waals force and hydrophobic interaction et, al. That optimum reaction conditions of inclusion compound of β_CD with EPA were: the mole ratio of β_CD/ EPA was 2.5∶1(mol/mol) and concentration ratio of β_CD/EPA was as follows: 14.00∶1(mol·L^(-1) /mol·L^(-1)) in the H_2O+ethanol solution, the included reaction time and temperature were 2.8 h and 25 ℃, respectively. And the thermal decomposition kinetics of inclusion compound of β_CD with EPA had been studied by using non_isothermal thermogravimetry. The results showed that the reaction order thermal decomposition β_CD and EPA was higher than first order. The average activation energy of the thermal decomposition calculated by using Ozawa(Ⅰ) and Reich method were 183.85 kJ/mol and 183.75 kJ/mol respectively.