Carbon dioxide used in sustainable polyurethane production


A team of researchers at the Fraunhofer Institute in Germany has used carbon dioxide and recycled material to make polyurethane in a more sustainable way.
The new process also avoids the use of toxic materials known as isocyanates, enabling safer production and biocompatibility.

Polyurethane is used as foam for mattresses, as packaging, elastic material for sporting goods, sealant, paint, adhesives, construction foam and much more. It is even used in medical applications, such as in tubes for intravenous catheters.

Instead of using fossil fuels such as oil or natural gas as a carbon source, the researchers used CO2 and polyurethane recyclates.
“This way, we can recycle the carbon and ensure that a lower amount of damaging CO2 is released into the atmosphere,” said project co-ordinator Dr Christoph Herfurth.

The team replaced isocyanates, which are normally used alongside chain extenders and polyols, with dicarbamate. “The polyurethane we produce in this way can also be certified as biocompatible,” said Dr Herfurth.

The process, which is already being used, requires high pressures and temperatures. The researchers are working on ways to optimise the technique to make it more efficient and industrially feasible, as well as working on more sustainable agents for foaming the polyurethanes.

The researchers aim to create three demonstrators to illustrate the various applications of the new form of polyurethane – tubes for medical applications, adhesives for bonding the tubes to devices such as catheters, and a polyurethane foam.