The invention relates to a novel
oil soluble viscosity breaking agent for thickened oil
recovery. The novel
oil soluble viscosity breaking agent for thickened oil
recovery consists of the following raw materials in part by weight: 60 to 80 parts of
maleic anhydride, 10 to 20 parts of para-hydroxyl
anisole, 130 to 170 parts of methylbenzene, 2 to 4 parts of crylic acid, 3 to 5 parts of para-toluenesulfonic acid, 0.2 to 0.6 part of azodiisobutyronitrile and 260 to 300 parts of
dichloroethane. The novel
oil soluble viscosity breaking agent for thickened oil
recovery is prepared by the following steps of: adding the
maleic anhydride, the para-hydroxyl
anisole and the methylbenzene into a reaction kettle; stirring and heating to 80 DEG C; after
dissolution, adding the crylic acid and the para-toluenesulfonic acid; performing
reflux reaction for 3 to 4 hours; cooling to
room temperature; filtering to obtain a
maleic anhydride solvent; placing the maleic anhydride
solvent into the
dichloroethane; heating to 60 DEG C; stirring for 2 to 3 hours; adding the azodiisobutyronitrile under the condition of introducing
nitrogen; heating to 90 to 100 DEG C; after 4 hours, stopping heating; washing by using a 10 percent
sodium hydroxide solution until the material is alkalescent; washing by using
distilled water until the material is neutral;
drying at the temperature of 40 DEG C for 6 hours, wherein the vacuum degree is -0.02 to -0.03 mpa; filtering;
drying at the temperature of 60 DEG C for 4 to 6 hours, wherein the vacuum degree is -0.05 to -0.06 mpa; and cooling to
room temperature to obtain the novel oil soluble viscosity breaking agent. The novel oil soluble viscosity breaking agent is needed to be used together with thin oil, wherein the ratio of the viscosity breaking agent to the thin oil is 1:4; and the adding amount of the pure agent is 1,300 to 5,000 ppm.