1. introduction: dbu, the “star” in water-based polyurethane catalysts in the chemical world, there is a substance like a star on the stage that can always attract everyone’s attention. it is 1,8-diazabicyclo[5.4.0]undec-7-ene), referred to as dbu. although this name looks like a tongue twister, it has extremely powerful functions, especially in the synthesis of water-based...