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Fire Phenomena of Rigid Polyurethane Foams
Martin Günther1, Alessandra Lorenzetti2, Bernhard Schartel3
1Bundesanstalt für Materialforschung und-prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany. martin.guenther2@bam.de.
Polymers
|April 10, 2019
Summary
Rigid polyurethane foams (RPUFs) show rapid flame spread due to low thermal inertia. Increasing foam density and using polyisocyanurate (PIR) foams improve fire resistance by altering combustion behavior.
Area of Science:
- Materials Science
- Polymer Chemistry
- Fire Safety Engineering
Background:
- Rigid polyurethane foams (RPUFs) present fire safety challenges due to rapid ignition and flame spread.
- Understanding the combustion mechanisms of different blowing agent formulations (pentane, water) and foam types (PUR, PIR) is crucial.
Purpose of the Study:
- To comprehensively investigate the fire phenomena and combustion behavior of rigid polyurethane foams.
- To elucidate the influence of foam density and composition on fire performance.
Main Methods:
- Thermogravimetry (TG) for thermophysical properties.
- Limiting Oxygen Index (LOI) and cone calorimetry for flammability.
- In-situ thermocouple measurements and Scanning Electron Microscopy (SEM) for morphological analysis.
Main Results:
- In-depth radiation absorption significantly impacts ignition time.
- Higher foam density shifts burning behavior towards solid-like characteristics.
- Polyisocyanurate (PIR) foams demonstrate superior fire performance due to retained cellular structure in residue.
Conclusions:
- The study provides detailed insights into RPUF combustion processes.
- Foam density and PIR composition are key factors influencing fire resistance.
- Cellular structure integrity plays a vital role in the enhanced fire performance of PIR foams.
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