Self-polycondensation reaction of polyurethane isocyanate

——carbodiimideunder organic phosphine catalyst and heating conditions, isocyanate can undergo self-condensation polymerization reaction. compounds containing carbodiimino groups (—ncn—) are generated. this reaction is another important autopolymerization reaction besides isocyanate trimerization and dimerization. organophosphine catalysts include 1-phenyl-3-methylphosphine-1-oxide (structural formula as follows), triethyl phosphate, triphenylphosphine oxide, etc. the pentacyclic phosphine oxygen type catalyst has good effect and…