本发明涉及制备含有脲基甲酸酯以及异氰脲酸酯基团的多异氰酸酯的方法，具体涉及一种生物基型五亚甲基二异氰酸酯固化剂及其制备方法与应用。本发明提供的生物基型五亚甲基二异氰酸酯固化剂的制备方法，可制备含有脲基甲酸酯以及异氰脲酸酯基团的多异氰酸酯固化剂，其是将水解氯浓度0～50ppm的PDI单体与催化剂A混合后，预反应0～5h，PDI三聚体催化剂在混合溶剂(溶剂B与溶剂C)稀释下匀速分段滴加，进行聚合反应，在转化率达到30％‑40％，加入阻聚剂终止反应，加入抗氧剂D后，经薄膜蒸发器和分子蒸馏器两级分离得到PDI型多异氰酸酯组合物，产品中的残余PDI单体≤0 .5％，黏度低，颜色浅，同时与羟基树脂的相容性好，具备反应活性高，光泽度高，耐化学介质性好等优点。

The present invention relates to a method for preparing polyisocyanates containing urea formate and isocyanurate groups, in particular to a biologically based pentamethylene diisocyanate curing agent and its preparation method and application. The preparation method of the biologically based pentamethylene diisocyanate curing agent provided by the present invention can prepare a polyisocyanate curing agent containing urea formate and isocyanurate groups. The method involves mixing PDI monomers with a hydrolysis chlorine concentration of 0-50ppm with catalyst A, pre reacting for 0-5h, and uniformly adding the PDI trimer catalyst in stages under dilution with a mixed solvent (solvent B and solvent C) for polymerization reaction, with a conversion rate of 30-40%, After adding an inhibitor to terminate the reaction, antioxidant D is added, and a PDI type polyisocyanate composition is obtained through two-stage separation through a thin film evaporator and molecular distillation. The residual PDI monomer in the product is ≤ 0.5%, with low viscosity, light color, good compatibility with hydroxyl resin, high reactivity, high glossiness, and good resistance to chemical media.