Preparation Of 5-hydroxymethylfurfural And Several Furan-based Polyesters

5-hydrozymethylfurfural(HMF)have been received much attention for its high activity and wide application,and expected to be a new "platform chemical".Usually,HMF can be produced by the dehydration of D-fructose.In view of green and efficient synthesis of HMF,our reactions are conducted in the aqueous system with heteropolyacid(HPA)as catalyst.Some factors including reaction time,temperature,solvent, additives,catalyst,amount of catalyst,concentration of fructose are investigated in this thesis. The result shows that:high temperature is beneficial to the selectivity;the addition of sodium chloride and Polyvinylpyrrolidone(PVP)can restrain the side reactions evidently;the catalytic activity of MxHy-xPA is almost equal to the corresponding HPA.The optimum conditions are drawn as follows:fructose 0.3 g,saturated salt solution(containing PVP 5 wt% based on fructose),165℃,10 min.The yield of HMF is up to 70.2%in the optimum conditions.Besides,the immobilization of HPA in different porous materials,and activities of these modified catalysts are investigated too.The catalyst immobilized in M₁H₂PA1/MCM-41 by impregnating method gives a best result with the yield of HMF being 60.2%,52.3%,and 50.1%in the three successive runs,respectively.In addition,some preliminary works on the synthesis of several furan-based polyesters are included in this thesis.These polyesters are all analyzed by ¹H NMR,gel permeation in chromatography(GPC),and thermogravimetric anaylsis(TGA).