PH Insulation’s R&D Center experts have tested a new PIR system with graphite pursuing increase of fire resistance characteristics of sandwich panels with polyisocyanurate foam. The new system has received the brand name PIR GT.
To create the new PIR system, the R&D Center specialists have conducted tests with over 20 different types of graphite from 18 suppliers from around the world. The samples have been tested in the combustion chamber of the R&D Center according to ISO 11925-2:2010 “Construction materials. Test method for flammability under the influence of small flame”.
The addition of graphite to polyisocyanurate foam has significantly increased the fire resistance of the resulting foam samples.
Experiments with the addition of graphite to PIR are being carried out around the world, but we still have not seen a system that really works. A few years ago, we also joined this race.
We were pleasantly surprised with results of the combustion tests of the new system. Increasing in the amount of graphite in the total foam volume to an average of 60%, resulted in samples self-extinguishing fire 4 times faster compared to standard PIR samples. We have witnessed the increase of the fire-resistant properties of the PIR system as a whole. The reason is quite obvious: graphite is one of the modifications of carbon: its combustion temperature exceeds 3500 degrees Celsius.
However, we have also revealed some challenges of the new additive to work upon: the more graphite, the less steady becomes the polyisocyanurate foam. Moreover, the structure of graphite does not allow it to dissolve in the polyol, so it settles to the bottom over time.
Head of PH Insulation R&D Center
In 2023, the PH Insulation’s R&D Center will continue experiments with graphite to increase fire resistance of PIR systems.