Preparation method of polyester synthesis composite catalyst

A method of preparing a composite catalyst for polyester synthesis, comprising the steps of:

• 1) performing a hydrolysis reaction by dissolving a titanium compound, a silicon compound and a tin compound in an organic solvent and adding therein a water solution of an acidic compound or a water solution of an alkaline compound at a temperature of 15° C.˜30° C. for 0.5 hour˜1 hour, wherein the water solution of the acidic compound has a pH of 1˜4 and the water solution of the alkaline compound has a pH of 11˜14;
• and
• 2) collecting, after the hydrolysis reaction, a hydrolysis precipitate and washing the hydrolysis precipitate with a deionized water to obtain the composite catalyst, wherein the titanium compound is of a formula of Ti(OR1)4, where is C2-4-alkeyl;
• wherein the silicon compound is of a formula of Si(OR2)4, where R2 is C2-4-alkeyl;
• wherein the tin compound is tin tetrachloride;
• wherein a molar ratio of the silicon compound to the titanium compound is 0.05:1˜0.5:1;
• and
• wherein a molar ratio of the tin compound to the titanium compound is 0.1:1˜5:1.