The invention discloses a manufacturing method for producing an unsaturated vibrin by utilizing the wastes and the distilling fractions generated during a
phthalic anhydride production process, which belongs to the composing manufacture industry of a
macromolecule compound. In the invention, the wastes, the distilling fractions,
diethylene glycol, glycol and a catalyst are firstly fed into a reaction kettle and mixed uniformly; the temperature is gradually raised; when the temperature of the reaction kettle is raised to 200 DEG C, the temperature is controlled to be 200 to 220 DEG C for about 3 to 8 hours; when an
acid value achieves to 35 to 40, vacuumizing is carried out for 1 to 2h; then a
polymerization inhibitor and cinnamene are added into a diluting kettle; the adding amount of the
polymerization inhibitor is 100 to 200ppm; when the
acid value of the reaction kettle reaches a theoretical value (30 to 35), the temperature is reduced to 150 to 170 DEG C; then the unsaturated vibrin in the reaction kettle is transferred into the diluting kettle for
dilution, adjusted into a proper
viscosity and packaged. The technique of the method of the invention is simple and changes wastes to be valuable as well as changes the harm into benefit; in addition, the method of the invention can generate excellent
economic benefits, reduce the
pollution of the wastes to the environment and is beneficial to environment protection.