The invention relates to a preparation method for high melt strength poly
lactic acid, and an extruder thereof. The raw materials comprise, by weight, 100 parts of a poly
lactic acid resin, 1-3 parts of a reaction chain
extender, and 0.1-3 parts of an
antioxidant. The preparation method comprises:
drying the poly
lactic acid resin, mixing the poly lactic acid resin, the reaction chain
extender and the
antioxidant according to the weight part ratio, adding the resulting mixture to an extruder, and carrying out extruding through the extruder to obtain the high melt strength poly lactic acid, wherein the extruder comprises a primary stage extruder and a
secondary stage extruder, the primary stage extruder and the
secondary stage extruder are respectively provided with a temperature sensor and a heating device, the primary stage extruder is a
twin screw extruder, the
secondary stage extruder is a single screw extruder, the primary stage extruder is provided with a first material inlet and a first material outlet, the secondary stage extruder is provided with a second material inlet and a second material outlet, and the first material outlet is connected with the second material inlet. With the method of the present invention, the production method and the device thereof are provided, wherein the method adopts the double-single series reaction extruder structure to prepare the high melt strength poly lactic acid material, and is suitable for continuous
mass production of the poly lactic acid material with the
long chain branched structure.