This is the second article examining more sustainable alternatives to virgin PU foam. In the first article, we looked at developments using lignin. In this final article, we examine other alternatives being developed to avoid the use of virgin PU, with the aim of reducing environmental impacts. Finding alternatives to PU foam is crucial for the furniture industry as the foam they use accounts for 105 million tonnes of CO2 emissions annually. Manufacturing an armchair, for example, emits an average of 43 kg CO2, almost half of which is due to the use of foam.
Why not avoid using foam altogether? That is, after all, what the waste hierarchy recommends as the best approach. Taking this advice Pearson Loyd developed a range of foam-free seating suitable for the workplace for Modus. ‘Made using coconut fibre, waste from the food industry, layered with wool [and natural latex] over steel springs within a timber frame, Edge Free has also been engineered to have a lower frame weight, a 33% reduction in weight, which makes this collection less carbon intensive in all its transportation phases.’
Another UK company is also taking the same approach and avoiding PU foams altogether. SCP use 100% natural and sustainable materials across their range. For padding burlap (jute fibres), latex and coconut fibres, as well as wool, feathers, and latex, are all used. While these attempts at avoidance should be applauded, they do result in higher costs, which of course are passed on to the end user.
PU foams are difficult to recycle but JLR, makers of Jaguar and Land Rover, have partnered with Dow and Adient to develop a closed loop recycling system. Foam from old seats can now be recycled, using (not specified) advanced recycling technologies, for use in seats destined for new luxury vehicles. JLR claims, ‘the recycled foam will be one element to a new ‘circular seat’ that it is estimated will half CO2e emissions impact while maintaining high performance, avoiding over 44kg of CO2e per seat.’ While it all sounds fabulous a footnote at the very end of the webpage announcing this innovation notes: ‘Initial lab testing proved technical feasibility based on 20% closed‑loop re‑polyol content. Next stage testing aims to increase percentage as high as viably possible.’ Rather an important disclaimer!
Spring Bond Ultraflex is made in the UK from recycled PET bottles and is suitable for upholstery and mattress uses.
While high-end brands can experiment with these alternatives manufacturers servicing the mass market are searching for more economical alternatives to virgin PU foam.
Agoprene has been specifically developed to replace PU foam as padding in furniture upholstery. It is derived from renewable seaweed biomass and other bio-based ingredients, which are processed (using renewable energy) into fire-retardant foams which can be produced at various densities. Agoprene is produced (in Norway) in sheets rather than large blocks, or moulded into specific shapes, and can be tailored to have minimal air pockets to ensure a dense seat that does not easily deflate over time. However, once it is buried it will decompose naturally over about 8 months. The manufacturers claim that the material is suitable for other applications including shoes (both padding and insole).
Brighi claims to have developed sustainable foams made from renewable sources, including bio-polyols derived from vegetable oils like soybean, castor, or palm.
Vita has developed foams ‘infused with‘ castor oil or soy oil-based polyols, although details of the materials and their sustainability benefits are not given.
Mycelium (fungi roots) offers promising potential as a replacement for PU foams. Indeed a large number of organisations are already experimenting or using mycelium foam for packaging solutions, for example, Ecovative. With many projects underway it is likely that materials suitable for furniture will soon be available.
The footwear industry is also always looking for alternative more sustainable materials. A Vietnamese company has launched Cirql Zero, a fully biodegradable, industrially-compostable midsole component. ‘Using our patented, chemical-free foaming for which Cirql is known, we developed Cirql Zero with a proprietary manufacturing process that can be deployed by any factory with supercritical foaming capabilities. Cirql Zero expands opportunities for footwear brands to reach climate and sustainability goals for their products and work toward true circularity in footwear,’ the company claims. At the end of the product’s life, Cirql Zero is fully compostable in industrial composting facilities. Also, check out Simplifyber (previously featured in this blog) who have taken a holistic approach to driving down emissions caused by the footwear industry.
See also my article on Tunera foam from Natural Fibre Welding, which has produced a foam alternative using natural rubber, vegetable oil, minerals and cork.
While alternative materials remain scarce, sustainably minded designers need to consider avoidance as a strategy to accelerate change. These two articles demonstrate that there are plenty of new materials on the horizon and that the days of virgin PU foam are numbered.
See also:
Soft, Strong, and Sustainable? The Quest for Better Foam
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