In this work we present a study of polyisocyanurate (PIR) foams synthesized with the HFO 1233zd(E) (LBA). The effect of LBA content on the density, cellular structure, mechanical properties and thermal conductivity upon aging of polyisocyanurate foams has been evaluated. The obtained results showed that the foams produced with higher LBA content have lower density. In addition, all foams have similar cell sizes (around 900 microns) and the use of LBA as blowing agent induced the generation of foams with a very homogeneous cellular structure.

The initial thermal conductivity and the aged thermal conductivity has been studied using an accelerated laboratory test method that allows predicting the thermal conductivity up to 25 years by measuring for 90 days. The initial values of the thermal conductivity were very low, in the range of 20 to 22 mW/mK. These values increase to reach values in the range 30 to 32 mW/mK after the aging process. (figure 1). The rate of aging has been correlated with the content of HFO used to produce the foam and with the temperature reached during foaming. A higher amount of HFO allows producing foams with a slower aging of the thermal conductivity.

As a final conclusion, it can be said that LBA is a good alternative to replace traditional foaming agents, due to the strong improvement achieved for the aged thermal conductivity values when it is used for the production of PIR foams. The results obtained in this work shows how using HFO in combination with PIR systems opens the possibility of producing more efficient and environmentally sustainable foams.