Footwear has an outsized footprint on the environment. The modern sneaker is generally designed to be used for a year or two, yet traditional materials last for decades in landfill, and plastics, glues, and coatings can be toxic.
Materials innovation can have a positive impact on brands, especially those designing reusable or circular products. Up to 80 percent of a brand's environmental footprint comes from the raw materials used in its production, according to the Higg Materials Sustainability Index.
So what if we rethink sustainability from the ground – or at least the foot – up?
This is the challenge that Thousand Fell took on through an 18-month development process, creating new bio-textiles out of castor bean oil, sugar cane, coconut husk, and palm leaf fibers. The brand calls materials innovation their "superpower" and designed the shoe with circularity in mind. All components are selected for their reuse capability – bean-based foams can be down-cycled into construction materials.
Here co-founder Stuart Ahlum talks about the R&D process and how the brand is continually developing new materials technology.
“There are 100 billion garments that are gonna go to landfill in the next five years. Most of those are already manufactured and made, so we're not giving up on that product.” Thousand Fell
Thousand Fell sneakers are made with coconut and sugar cane. How did you develop this material?
We kind of started at the end where we were looking for products that were regenerative or renewable, or products that could be recycled really efficiently. And so we kind of have two camps of materials within our products; one is the natural substitutes where we're using bio polyoils instead of petroleum – coconut husk, sugarcane, palm tree leaf, and regenerative wood instead of your standard plastics – and fibers, pulling a lot of that from the post-industrial space. The second bit is still synthetic, so we still use rPET, but we selected that because it allowed us to actually recycle it. So we can turn rPET uppers back into rPET pellets and then into yarns and back into textiles. So it really allows us to build out these clean material feeds for recycling.
When you say you have these bio polyoils, how did you research those? Were you working with an in-house team?
We did a lot of work in conjunction with mills and what they were seeing was a kind of pressure from two different angles. There was a little bit on the sustainability side, there was a little bit also on the cost side, but they were seeing that petroleum inputs could be replaced with oils from bio byproducts, whether that's soy or castor bean or corn. So they were developing a lot of these lines with other in-uses, whether that's mattresses or for high-density foams. We came in and were like, 'Listen, we actually think this could be a really effective use in footwear. Could we test in some of this?' Then tested some of it and tweaked some of it in order for it to meet sort of SATRA test strength and our durability standards for footwear. So it was a little peculiar. I think we're the only footwear [brand] they work with. So it was it was in part pushed by the mills themselves, and in part kind of pushed by us to what we needed with footwear.
When we started in the footwear space, what was super interesting was that a lot of the mills were leading a lot of this material innovation. They were recognizing that brands were coming to them and saying 'Hey, do you have anything that's sustainable? Do you have anything that's renewable?' and they knew their formulations really, really well. They were able to test over the past 10 years some of these substitutes, so that's where you're getting a lot of this material innovation from. Brands now have the ability to weave that into the existing supply chain and existing product lines at scale, at cost, same in-use and usability, and durability. And that's been really amazing.
Were these suppliers that you were already working with and they came up with these materials? Or did you really sort of push that forward to find new ones?
We reached out to suppliers and we did it two different ways. One, we reached out through preferred vendors of teams like Lenzig and a couple of others that are mills that we've worked with that are doing really innovative stuff. The second thing that we did was we also identified partners that were the biggest players within their category, whether that was cotton, or rPET uppers, or rubber. We do all of the manufacturing in Brazil. They test, substituting soy or whatever, for example, or say we could take some of this fiber and do other inputs into it, whether that's sugar cane, or palm tree leaf, or coconut husk.
When you talk about recycling the plastics that you are using and spinning them into fibers, do the facilities exist? Is this an easy thing to do?
The technology exists [but] it's all very disparate, and there are a lot of very high bars to hurdle in order to access it, and that's a little oblique. The misconception is that recycling technology is so, so far away from being at scale for retail, and in truth, that's actually not the case. Recycling technology, especially mechanical recycling – that's actually taking cotton or polyester or nylon or rubber even, and doing some sort of shred or grind to get it back into the condition [of] a cotton ball and being able to have a blended, essentially raw fiber pile that can then be extruded back into yarns and then knitted back into textiles. All that technology is here and ready and available, it's really just geared towards the post-industrial machine. The reason why is because you need really consistent inputs, and you need a lot of it. The issue with retail is that it's hard to aggregate enough of that sorted into a way that you know exactly what's coming back and replicate the same clean material feeds at the same scale as your post-industrial feeds.
Are you looking at other new textiles and materials to experiment with?
We actively are. Our goal here has always been to push with material innovation. And sometimes the material innovation is kind of hiding in plain sight – we're going to be launching some really cool stuff with new silhouettes at a lower price point that kind of compare more closely to what you'd see in like the Vans and the Converse world, but the materials that we're using are much, much better from a sustainability POV, from an environmental impact, and from a carbon footprint. We are going to be launching another silhouette that's still in the leather material that includes rPET base that can recycle with a corn waste resin over the top of it. So again, a polyoil instead of petroleum. Then what we're actively doing is we're always testing new materials. Material innovation is very much at the core of it, but it's material innovation for recycling. It's a test kitchen of sorts.
How do you get plugged into these worlds? Is it difficult to find these suppliers?
I would say initially, it's really hard. And then, now that we've been in it for a while, it's a nice two-way street of inbound and outbound, and people are starting to know the brand a little bit, and so it's easier for us, but it's not easy. We've got a person on our team entirely dedicated to the sustainable sourcing side. There are a couple of good things, and with this too, like a lot of this early material, TK is but not quite yet at what they would call a commercial scale. When people think commercial scale, they're thinking like, how does a multinational brand incorporate this material? What's nice is, we can help with pilot programs, and we can help with smaller batch runs. And we can say like, great, you know, like, if you guys aren't quite a commercial scale yet, no problem, we'll take, you know, a couple 1000 Linear meters, we'll make a pilot program out of this will help you guys scale. So it's a way for us to also dip a toe in and help some of these earlier programs get off the ground, which is, which is always fun.
So when you are looking at your recycling capability, where are you at?
We're not able to fiber-to-fiber recycle everything. And by that, I mean, you've got a garment, you're able to recycle it, and from that, you create a usable yarn that can then be of a high enough quality to make a new garment. We're saying with footwear, it's componentry – like an old outsole into a new outsole. We can do that with a lot of materials - we can do that with cotton, polyester, nylon, wool, and rubber. We're actively trying to get that with cellulose. In our case, it's footwear, too. And we're starting to see more teams taking a page out of the Thousand Fell book and trying to build footwear roughly within those material feeds because that's what's easiest to recycle. I don't think we're 100% there by any means. When I think about some of the foam that we have, we actually do down cycling with those foams. So we're not actually taking that foam and turning it back into new foam that's used in an insole, etc., we're taking that foam, and it's going into insulation or into the upholstery. You can actually recycle foam, but the way to do it is you add a ton of adhesive and then like essentially spray it onto the inside of a product, which then makes the second product non-recyclable. So like you would get gotten one more turn had we gone kind of componentry to componentry. But then it would have ruined the next product. So we opted to go downcycling there, and as part of super circle, downcycling is a very real solution right now.
With coconut husk we're not doing fiber to fiber, we're actually doing composting there, but it's usable compost. It's not this like crazy industrial composting over 60 days that doesn't yield. It's good fertilizer, it's actually a useful product.
What's interesting here is that Thousand Fell had the luxury of designing for circularity from day one. The majority of fashion brands and retail brands out there don't have that luxury, and there needs to be a solution for this legacy product. Because there are 100 billion garments that are gonna go to landfill in the next five years. Most of those are already manufactured and made, so we're not giving up on that product. What we're doing instead is we're making sure that it's being captured and downcycled, so it's at least getting one more turn through the system, which I think is really important.
Note: Bucha Bio rebranded to Rheom Materials in January 2024 to better reflect their process and offerings. The new name combines the Greek word "rhéō" (meaning "flow") and "form," describing how a melt-extruder works, where the biopolymers flow into place and then solidify, or form, the final product.
