Traditionally, petrochemical based physical products are manufactured, used by consumers and then thrown away to be landfilled or incinerated - this has been the case for flexible PU foam products.
We must remember that PU foam is irreplaceable in terms of the comfort it provides, it’s durability and the economics associated with manufacturing and supply chains. However, in the new age of sustainability and circularity we must find a way to make flexible PU foam more sustainable and circular.
All the players in the supply chain are aware of these issues and are developing and marketing innovative products that reduce the carbon impact and address the ‘end of life’ issues associated with flexible PU foam products.
The point of this presentation is simply to highlight that there is no one solution to this challenge and all of us will have to adopt a range of strategies to make flexible PU foam as sustainable and as circular as possible. There is no ‘silver bullet’ to solve this problem.
The solution will clearly have to include alternative raw materials produced from sustainable raw materials. Current projects are looking at polyols based on soy bean, castor oil, palm oil, sun flower oil, palm oil and rape seed. These alternative natural sources of polyols clearly resolve the connection with petrochemicals and fossil fuels but in all cases we must ensure that all the environmental impacts of these supply chains are considered including the impact on food supply chains, water usage and land use.
Ideally, the solution will also contain some end of life foam content. The utilisation of acidolysis/glycolysis technology, which was actually developed many years ago, to reprocess end of life mattresses into new polyol process is a truly circular option. The Dow Renuva project is a great example of this as end of life mattresses collected by Eco-mobilier will be reprocessed into polyol by Orrion chemicals and then used as a raw material for new products produced by Vita. The foams produced from this ‘re-polyol’ will have similar properties to products based on ‘virgin’ raw materials and will be used in all the same applications. There are other technologies being developed to make polyols from other waste polymers. Gasification, pyrolysis and hydrogenation are all technologies being studied with the intention of converting waste polymers into base chemicals that can then be converted into a range of polymers. This is arguably the most circular solution but the full environmental impact of these processes must again be carefully considered.
A simpler approach to the use of end of life foam is in PU foam rebond which can potentially be used to replace traditional flexible foam applications and also used for new applications.
In order to facilitate both the use of alternative raw materials in new products and the reprocessing of the end of life products, we will have to adopt ‘Eco design’ principles for both PU foam grades and the products produced from these foams. This process must also take into account the long time-scales associated with the typical life span of flexible PU products. The ‘Eco design’ process must take into account the choice of raw materials in order to avoid legacy chemical challenges in the future, design for recycling through reducing the number of component materials, the mechanical design and identification through labelling.
Clearly, creating ‘circular’ flexible PU foam products is a challenge and the industry will have to adopt multiple strategies to achieve this but there are both existing and emerging technologies that will enable this activity.