Method for reducing crystallization point of polyester type modified MDI

The invention relates to the technical field of modified MDI production, in particular to a method for reducing the crystallization point of polyester type modified MDI. According to the method for reducing the crystallization point of the polyester type modified MDI, polyester polyol and acetyl trihexyl citrate are added into diphenylmethane diisocyanate for a reaction, then acetyl trihexyl citrate and carbodiimide modified MDI are added for a reaction, and therefore the crystallization point of the polyester type modified MDI is reduced. The method disclosed by the invention is scientific, environment-friendly, green and healthy, the crystallization point of the polyester type modified MDI is obviously reduced, the use is convenient, and the production energy consumption is reduced. 本发明涉及改性MDI生产技术领域，具体涉及一种降低聚酯型改性MDI结晶点的方法。所述的降低聚酯型改性MDI结晶点的方法，先在二苯基甲烷二异氰酸酯中加入聚酯多元醇、乙酰基柠檬酸三己酯进行反应，再加入乙酰基柠檬酸三己酯、碳化二亚胺改性MDI进行反应，从而降低聚酯型改性MDI结晶点。本发明的方法科学环保，绿色健康，聚酯型改性MDI结晶点降低明显，使用方便，降低生产能耗。