A Quantitative Investigation of the Effect of the Recipe on the Trimer-yield in Polyisocyanurate Foams

Abstract

The effect of the recipe on the isocyanurate yield in polyisocyanurate (PIR) foams has been studied quantitatively using ATR—FTIR spectroscopy and the adiabatic temperature method based on the measurement of the reaction temperature during the course of the reaction. In this way, the effect of the index on the PIR reaction could be studied quantitatively. The significance of isocyanurate concentration and isocyanurate yield with respect to flammability properties is also investigated. It could also be shown that, for example, the presence of water reduces the isocyanurate yield dramatically. During an investigation of various commercially available PIR-catalysts, it is shown that potassium 2-ethylhexanoate in diethylene glycol (75: 25) leads to higher isocyanurate yields than potassium acetate in diethylene glycol (25: 75). Even when different concentrations of active components in commercially available catalysts are taken into account, this is still found to be the case.

Keywords

polyurethane polyisocyanurate isocyanurate conversion isocyanurate yield rigid foam burning behavior PIR-catalyst blowing agent

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