Surfing has a dirty secret: surfboard production techniques are often at odds with the sport’s eco-conscious image.
Most modern surfboards are a sandwich-like construction: a polyurethane foam core – known as a blank – coated in a fibre-reinforced composite. The reinforcements are usually glass, but they can also be carbon or plant fibres, like hemp and flax.
“There is a huge paradox between the idea we have of surfing and the materials we are using,” explains Pierre Pomiers from the French company Notox. “Most of the boards today are using dangerous material, for the health of the person manufacturing, but also for the environment, because we don’t know how to recycle materials like polyurethane, fibre glass and polyester resin.”
In 2006, Pomiers, who use to work in robotics, founded a startup, whose goal was to improve surfboard manufacturing. Now around 90% of the boards they produce are based on recycled EPS (expanded polystyrene) foam, renewable resources such as flax fibre and cork, and epoxy resins – for the composite – that are part bio-based.
They use recycled EPS foam blanks, Pomiers says, because there aren’t any decent bio-based alternatives. A simplified life-cycle assessment (LCA) – an analysis of the environmental impacts of a product’s life from raw material to end-of-life disposal – that the company uses, finds no real difference between bio-based options and recyclable EPS, he claims. This is mainly because the bio-based versions are not recyclable.
Indeed, the development of bio-based blanks is something the surf industry seems to have struggled with. A few years ago, there was hype around the idea of growing surfboard blanks from mushrooms, but it never took off. One Californian company that managed to create a mushroom-based surfboard switched to recycled EPS foam when they realised mushroom boards were going to be difficult to mass produce.
In 2013, two companies – Synbra and Tecniq – announced that they had developed “the world’s first certified 100% biodegradable and 99% bio-based surfboard foam”, but it has yet to come to market. Tecniq’s Managing Director, Rob Falken, says that they “are putting the finishing touches on the technology prior to commercial launch”, which he thinks will be in 2020, but adds that he “cannot publicly speak about the tech… at this time”.
According to Pomiers using flax and cork increases the sustainability of surfboard production because the waste off-cuts are non-toxic and can be recycled, for example to produce housing insulation. His company claims that making one of its surfboards produces a kilogramme of waste, 75 per cent of which can be recycled, while more common manufacturing processes result in around six kilogrammes of waste that is hard, if not impossible, to reuse.
Like most surfboards, however, these boards cannot be recycled. Once the composite has set, you cannot extract and process the different materials. But there is a solution on the horizon.
According to Jordi Oliva from RConcept, their partly-bio-based epoxy resins have around half the CO2 footprint of petroleum-based resins. And they use a hardener that makes them recyclable.
“We can dissolve the composite and split the matrix from the reinforcements,” Oliva explains. “It is a pretty easy process: you put the composite inside an acid solution, with a low PH, around three, and the matrix starts dissolving and once you rinse the reinforcement with water you can reuse it.”
Angela Daniela La Rosa, an expert in composite materials at the Norwegian University of Science and Technology, believes that such recycling systems could “work very well for sports equipment”. She says that end-of-life has always been the weak point of epoxy-based composites. “They can be ground and reused as powder,” she explains, “but you cannot separate the components.” She adds that the powder does not have a high value – it is often just used as a filler for other products.
When La Rosa tested hemp and carbon composites produced using a novel epoxy hardener that can be dissolved in a heated acid solution, she was able to recover what appeared to be good quality, clean fibres. Although she didn’t conduct detailed tests on the properties of the fibres, under a scanning electron microscope they looked similar to the original fibres.
The epoxy resin isn’t recoverable, but La Rosa explains that it is possible to extract a usable plastic from the acid solution, once the composite has dissolved.
A LCA of a recyclable composite reinforced with 300 grammes of carbon fibre showed that recycling the fibre would recover 523 Mégajoules of energy. This saving comes from avoiding the energy costs of making new carbon fibre for the next product. La Rosa says that this is significant because producing such a carbon fibre composite requires 600 Megajoules of energy. “You recover almost all the energy consumed in the production,” she explains. La Rosa hasn’t run a LCA of a recyclable hemp fibre composite.
Pomiers doesn’t think, however, that this form of recycling is a viable solution. “The problem is who will collect the products for dissembling them and separating the resin and fibre,” he says. “If a board breaks in Paris, who will send the board back to us? Nobody.” Instead he is working on another solution: 3D-printed boards.
For the last few years Pomiers has been developing 3D-printed surfboards from bioplastics, produced from cellulose. These surfboards, which he estimates will be available in two to three years, will not use any reinforcing fibres, instead the mechanical properties of the board will be tuned by their 3D-printed, internal honeycomb-like structure.
In theory, as these boards will be 100% thermoplastic, once finished with they could be recycled like other plastic products. They could even be melted down and fed back into a 3D-printer to make another surfboard.
Source: AllThings.bio, 2019-07-02.