Isocyanurate-containing polyisocyanate composition with stable chromaticity, and preparation method thereof

A preparation method for an isocyanurate-containing polyisocyanate composition with stable chromaticity, comprising the following steps:

• (1) reacting an isocyanate monomer in the presence of the catalyst;
• (2) adding a terminator into the system to terminate the reaction when the reaction reaches a target conversion rate, so as to obtain a prepolymer;
• (3) subjecting the product obtained in step (2) to separation treatment to remove the unreacted isocyanate monomer to obtain a crude isocyanurate-containing polyisocyanate composition;
• and
• (4) subjecting the crude polyisocyanate composition obtained in step (3) to heat treatment under high temperature and reduced pressure to obtain the isocyanurate-containing polyisocyanate composition with stable chromaticity;
• wherein step (2) further comprises adding a phosphate salt into the prepolymer after terminating the reaction;
• based on a total weight of the polyisocyanate composition, a cleavable amine content of the polyisocyanate composition is less than or equal to 20 ppm;
• the cleavable amine is a decomposition product of a catalyst used in preparing the isocyanurate-containing polyisocyanate composition.