Free Study: Ternary pentane blends show a potential for excellent long-term performance, which is an important parameter in the building industry.
Pentane blowing agents are widely used in the industry. Depending on the isomer used, the performance and characteristics of the foams may vary significantly. Haltermann Carless has explored the possibility of creating blends made from all three isomers n-, iso- and cyclopentanes. The results of these ternary pentane blends look promising and might offer additional benefits to the PU and PIR industry.
Haltermann Carless is the only European company that is in a position to offer all three pentane isomers, either in their pure state or as blends. Working closely with the polyurethane (PU) industry, which uses our pentanes as blowing agents, we have been able to gain valuable insights into the global market over the course of time.
In the recent past, chlorinated and fluorinated blowing agents were commonly used, avoiding pentanes as they are highly flammable. More recently and against a backdrop of environmental pollution and global warming concerns, pentanes now account for more than 50% of all blowing agents used in the PU (polyurethane) and PIR (polyisocyanurate) industry. Whereas pure pentanes and their binary blends are widely used, blends of all three isomers are rare and not described in scientific literature. This notwithstanding, ternary blends may have advantages for insulation board manufacturing that have so far not been identified.
To be able to offer our customers new product qualities, providing added value, whilst at the same time deepening our own knowledge, a series of experiments were set-up to further investigate this idea. For our experiments a standard PIR formulation was used to compare the performance of the different pentanes and blends. These experiments were planned and evaluated with the help of a design-of-experiment (DOE) software. We used the services of a specialised external laboratory to conduct the experiments. The behaviour of the PIR and the pentanes during the foaming process was recorded. In further steps, the fresh foam was examined for its insulation properties, artificially aged, and re-examined.
PU and PIR foams lose their insulation efficiency over time depending on the pentanes used. Therefore, we also recorded and evaluated the stability of the foam over the course of time.
The pentane blends for the most part showed the expected behaviour, but also revealed some interesting details:
- Cyclopentane-blown foam exhibits an excellent insulation efficiency but quickly loses its positive properties.
- Blends of iso-pentane are fairly stable and exhibit an insulation efficiency that can come close to that of cyclopentane foams over time.
- Ternary blends showed a good overall performance.
While our DOE model includes only relatively few experiments, the results and their interpretation lead us to believe that that ternary blends should be examined more closely for further applications. Ternary blends show a potential for excellent long-term performance, which is an important parameter in the building industry.
Would you like to get more information about our DOE study and the benefits of ternary pentanes?
The full article written by Dr. Henning Böckemeier, Technical Service & Development Manager at Haltermann Carless, was published in the Polyurethane Magazine (December 2019).