The Utilization of Rigid Polyurethane-Polyisocyanurate Foams by the Combined Alcoholysis-Aminolysis Process

摘要

Rigid PUR-PIR foams prepared (i) with addition or (ii) with no addition of a solid fraction of rye slops or potato slops were both alcoholyzed and aminolyzed. The alcoholyzate was used to replace the original poloyether polyol, 0.05-0.20 of chemical equivalent, which is used to prepare foams (Table 2). Three series of foams were prepared, varying in the amount of the alcoholyzate added. Apparent density, compression srtrength, brittleness, oxygen index, combustion residue, stability of linear dimensions, volume change (in 48 h at 120 deg C), and softening point (Table 3, Figs. 2-4) were determined. As the proportion of the alcoholyzate was raised from 0.05 to 0.2 chemical equivalent, the compression strength of the mode (ii) foams (foams 1.1-1.4) rose, whereas brittleness, oxygen index and softening point remained practically unaffected as compression with control foam (foam 1.0 with no alcoholyzate added). In the mode (i) foams (solid fraction of rye slops added) prepared with the alcoholyzate added (foams 2.1-2.4), the compression strength rose but slightly (from 208.7 kPa in control foam to 229.0 kPa softening point fell. The foams contianing the alcoholyzate and the solid fraction of potato slops (foams 3.1-3.4) exhibited not only lower brittleness and reduced softening points but also lower compression strengths. In each foam examined, the oxygen index and combustion residue remained poractically unaffected as compared with controls. IR specita confirmed the presence of the urethane and isocyanurate groups in the foams prepared.