Catalytic Synthesis Of The Acetals From Polyethers By The Solid Acids And The Study Of Their Hydrolysis And Biodegradation

three TiO2-ZrO2/SO42- type solid superacids were prepared with the ratio of Zr to Ti was 1:3,1:4,1:5 respectively .Their acidity were all less than -14.52 by Hammett method and the structure was determined by IR. Acetals were prepared by condensation of diethyleneglycol monobutyl ether with paraformaldehyde in the presence of the above catalysts. The optimum condition obtained was: the amount of catalyst 5%, reaction time 3h, catalyst type Zr:Ti=1 :4 and the yield was high to 83.9%. The effect of the different factors on the acetalation was discussed and the structureof the acetal was C4H9OCH2CH2OCH2CH2OCH2OCH2CH2OCH2CH2OC4H9 determined by IR,NMR.Three noncyclic acetal-linked cleavable surfactants were prepared based on the optimum condition by condensation of para formaldehyde with polyethers O-9, O-15, O-20. The yield was 88.6%, 81%, 75%, respectively and the structure was determined by NMR. Comparing with polyethers which were raw materials, the acetals' cloud points were decreased, surface tensions raised, foam heights were low and the emulsifications were improved. Comparing with polyether which had the similar molecular, except cloud point and viscosity ,the other properties of the acetal-linked cleavable surfactant were all improved : the surface tension was decreased from 40.1 mN·m-1 to 36.5 mN·m-1, the emulsification was improved from 153s to350s, the original foam height was reduced from 60mm to 35mm.The study of hydrolysis of acetals indicated that the hydrolytic rate constant of acetals of O-9(was abbreviated for O-9s) was increased nearly 20 times after emulsified and those of theO-15s and O-20s were only improved 1.4 to 2.38 times. All of them can ascend 1.14 to 1.38 times further. When the pH value was invariable, the hydrolytic rate was accelerated as the temperature raised. The change range of hydrolytic rate was larger in high temperature when pH was high and was opposite when pH was low. When the temperature was fixed, the hydrolytic rate was fasterwith the lower of pH value. The more the molecular of acetal was, the more sensitive the hydrolysis to pH was. The low active energy can make hydrolysis fast. Hydrolytic Kinetics was studied and the result was: the hydrolytic formula was first class and the hydrolytic rate constant, half life, active energy were all obtained.The pH value of O-9s, O-20s and O-20s'(after hydrolysis) were decreased from 7 to 5.5 and from 9 to 6.5,respectively. The turbidity of O-20s' was more obviously than that of O-20s and the rate of biodegradation rate of O-20s' was the fastest, the O-20s was the second and the O-9s was the third. The biodegradation kinetics formula was the first class and accorded with the experimental data.