Chemistry, Materials & Packaging
Q&A:
DuPont Sorona and the Evolution, and Revolution, of Biomaterials

Over his more than 30 years in the business, Mike Saltzberg has seen firsthand how sustainability has grown to be of equal consideration with technical performance and cost in the development of new biomaterials.

Saltzberg is the Global Business Director for Biomaterials at DuPont Industrial Biosciences, the team that ideates and develops products derived from bio-based materials. Among their innovations is DuPont™ Sorona®, a partially plant-based fiber increasingly used in apparel and carpet.

We spoke with Saltzberg to learn more about the evolution of biomaterials and products such as Sorona®.

Throughout your 30+-year career at DuPont, with the last 12 being involved with Biomaterials, how has your work evolved as sustainability gained more traction as a global priority? What do you see as the biggest levers to create change in the materials science space?

Mike Saltzberg: It used to be that people would always talk about technical performance and cost whenever they were thinking about a new material, and sustainability was sort of a nice-to-have or compliance mandatory because of regulations. It’s come to the point now where the sustainability of a material — where it comes from, how it’s made, what its end-of-life scenarios are — has become at least of equal importance to technical performance and cost.

For us, dialling in sustainability has become much more important as time’s gone on. As materials suppliers, we can affect broad ranges in multiple industries. We can have a big impact because our customers, who are making the products that consumers or industry want to buy, are counting on us to bring them more sustainable materials that will still work in their processes. We have a role to play in bringing out more sustainable materials that also have high performance that can meet the customer’s needs.

This project that we’re known for, DuPont Sorona — we started working on that more than 20 years ago. So, this thought process has been around at DuPont for quite some time. If you’re starting with something really innovative, to research the idea and get it through to the market takes time.

DuPont™ Sorona® is made up of 37 percent annually renewable plant-based ingredients — can you walk us through the process of how it is made?

The beginning of the bio-PDO process was commercialized in October of 2006, and the Sorona business kicked off in January of 2007. So, we’ve been around now for about 11-and-a-half years. It’s a fantastic polymer that has some really nice properties. For example, Sorona makes a carpet that’s super soft and resilient and has built-in stain resistance that doesn’t require any chemicals on the surface. In apparel, it gives some of the garments stretch, similar to what you can do with spandex but a little bit different; a lot of softness, a lot of comfort. It was a difficult and expensive process to make both of the chemicals that are required to make it from petroleum. So, using this natural process from a renewable intermediate is not only more environmentally friendly, it’s also more effective and lower cost.

How do you see sustainability, product performance and innovation interacting when it comes to materials development?

MS: A lot of times in the biomaterials space, customers are asked to compromise. They’re told, “Here’s a product that doesn’t work quite as well as the one made from petroleum, but it’s natural or it’s made from renewable resources. It doesn’t have the same technical performance, but you should use it anyway because the process is better.” Or, “Here’s a material that can do what you want it to do and has a better sustainability profile, but it’s substantially more expensive.” Our belief is that’s not going to work.

We’re trying to have significant impact. We don’t just want to have niche, little products for those with higher income. We try to come up with solutions that first and foremost, have fantastic technical performance that will sell based on that. There’s a knock on biomaterials that they’re worse-performing, but ours are not; Sorona is a better polymer [than its petroleum-based alternative]. There also has to be a cost point that if it is a little bit more, the value has to be there so that the product sells itself.

For us, sustainability is now table stakes. We’re not ever going to bring out a new material that doesn’t, for example, have a better life cycle analysis (LCA) and a responsible end-of-life story. All of the materials that we bring out at DuPont Biomaterials have a substantially better LCA than the materials they replace and are either recyclable or biodegradable. That’s how we approach it: Performance first and sustainability integrated, too. Otherwise, why are we spending the innovation to introduce a new material? If it’s not better in all the dimensions, we shouldn’t be bringing it to market.

It’s been a great story for Sorona. It’s been embraced by the market — and the business has grown. We’ll be over $300 million this year in sales.

It’s great to hear that there’s been such a strong shift towards valuing LCA and improving end-of-life practices.

MS: The big retailers and consumer product companies have recognized that their consumers care about that now. So, they’re now telling the materials suppliers, “You’ve got to meet my sustainability goals.” In the past, consumers were just talking about it. They were not changing their buying behavior; if you wanted them to pay an extra penny or do something that was a little bit inconvenient, they wouldn’t do it. That’s really changed. It’s a generational change and a mindset change — that’s what’s driving the consumer product groups and then they drive us.

To your earlier point, as a materials supplier, you can also influence upstream producers and product manufacturers, as well.

MS: There’s no doubt. We have to reach all the way back — some of our partners are involved in the actual harvesting of the corn, and we have to go all the way back to that to make sure it’s all done in the right way.

You recently launched a new partnership with Archer Daniels Midland. Can you tell us more about this partnership and why we should be excited about it?

MS: Archer Daniels Midland is the world’s largest processor of corn; they have expertise in how to get renewable feedstocks that can be used to make renewable chemicals. They also are a company with deep knowledge of the chemistry of carbohydrates such as corn starch. Working with them, we’ve developed a process to take fructose from corn starch and through a chemical process — not a biotech process, in this case — and can make a monomer called FDME. That monomer allows us to make a family of polymers called furan polymers that have really exciting properties for beverage packaging.

If you’ve ever noticed that a plastic water bottle is much thinner than a plastic soda bottle, it’s because that soda bottle not only has to keep the liquid contained but it also has to keep the carbonation inside, so the soda doesn’t go flat. PET isn’t great at doing that, which is why they have to put a pretty thick wall on it to keep the CO2 inside. You could greatly reduce the amount of plastic and still maintain the same shelf life of the soda if you could keep the barrier properties needed to hold the CO2 inside of that plastic. Together with ADM, DuPont has developed a plastic that can do that and can either be used by itself or mixed with PET to improve the barrier properties substantially. On top of this, the plastic is made primarily from a renewable resource, as well — corn starch or fructose — and it allows us to substantially reduce the amount of plastic required to package beverages. I’m really energized about this partnership and its impact.

Another recent development from DuPont Biomaterials is an enzymatic polymerization technology that enables access to a range of engineered polysaccharide materials, which are renewable and inherently biodegradable. How can innovations such as this empower DuPont Biomaterials’ customers?

MS: Basically, nature has many different polymers of sugar — that’s basically what polysaccharides are — and they’re used commercially. Cellulose is used in paper; cellulose acetate goes into eyeglasses; and then there’s other things like guar gum, that’s used in food and oil well production. Nature makes them in a plant, then humans harvest the plant, chop it up and use chemicals to dissolve the rest of it and what’s left is the pure cellulose. That’s the way we work with polysaccharides today.

What DuPont has developed mimics what nature does. When nature makes cellulose in a tree, [it] takes in CO2 from the air and sunlight and uses these enzymes — natural catalysts — inside the tree to create sugar and then polymerize that sugar together into long chains, which are cellulose. What we’ve done is develop enzymes of our own.

We can start with regular cane or beet sugar — like you would put in your coffee — and by mixing it together with this enzyme, we can break the bonds inside that sugar and string together the molecules to form exactly the polymer that we want. The process is done at room temperature and room pressure [and] is done with water and sugar and a little bit of an enzyme; we can design fantastic new polymers directly from sugar in a very environmentally friendly way. Of course, because they’re made from sugar, they are biodegradable.

What’s interesting about polysaccharides is that they can have a whole range of properties. Cellulose will sit around for 100 years in a tree; it’s very durable. Or corn starch — another polymer of sugar — they’re both made from the same units but because they have a slightly different structure, corn starch dissolves in water and cellulose is extremely durable. Using enzymes to polymerize sugar, we can make a whole variety of different materials with fantastic properties, so it’s a great new process and we’re very excited about it.

You mentioned a variety of applications — can you share some examples?

MS: Sure! Some that we’re looking at include a paper-making operation. More and more people want to use recycled paper pulp, but that pulp is a lower quality than the fresh pulp, [so] the paper is weaker. If we add some of our polysaccharides in a very small amount to the paper-making process, we can enhance the strength of the paper, which allows you to use more recycled pulp and less virgin pulp.

Another example: If you think about the feeling of an acrylic sweater compared to a cotton sweater, the difference in comfort is really extreme. Cotton is a polysaccharide, so it’s natural; it breathes and it’s very comfortable. Acrylic has a lot of great properties, but because it’s a pure synthetic, it doesn’t have that same breathability. We’re finding that we can add it to some of these synthetic fiber materials and make them feel more natural and give them better properties.

Speaking of textiles, DuPont is a participant in the Ellen MacArthur Foundation’s ‘Make Fashion Circular’ initiative — can you tell us more about DuPont Biomaterials’ role in the initiative?

MS: We’re really thrilled to be part of what the Ellen MacArthur Foundation is doing. We’re also working in the Circular Economy 100 (CE100), which is sort of a precompetitive innovation program. We’re involved with both of those because we think in order to really make change in industry, we have to have collaboration all the way from the beginning, through material suppliers to all of the people who work throughout the value chain.

In the fashion industry, for example, we start with corn and make a monomer, we make a polymer, our customers turn that into a fiber, it’s woven into a fabric that’s made into a garment, and then someone has to dispose of that garment eventually in some way or another. It’s a very long value chain. We’ve all got to work together if we’re going to make an impact on the fashion industry. So, that’s what we’re really eager about with Make Fashion Circular; it’s a whole bunch of different industry partners. There are brands that everybody knows — like adidas, Burberry, Nike — but there’s also material suppliers like us and Gore; there’s people that are really interested in trying to make new raw materials. And we’re working to bring the whole value chain together to make holistic solutions.

It’s just getting started, but they had the first workshop recently in London. We’re looking at how companies can support key issues. One of them is business models that keep clothes in use, looking at longevity and durability in the world of fast fashion. Another is materials that are both renewable and safe; that’s a big area for us. How can we teach the industry to use more of these materials so that the renewable part really helps with these materials?

We believe that where the materials come from, how they’re used and how they’re disposed of — all three of them matter. A lot of the time when people hear ‘circular economy,’ all they’re thinking of is the last piece. But really, if you take a material that is very extractive from the earth and has a terrible process to make it, and then it’s biodegradable, that’s not really solving the problem. You have to look at all three parts.

The final area they’re looking at is turning used clothes into new clothes. They may need some chemical process or materials initiative that we at DuPont can contribute to, and I think that’s how we’re going to come up with great solutions. We’ll bring a different perspective than a garment maker or retailer will.

Is there anything else that you’d like to share with SB readers?

MS: It’s been so long that people have been waiting for the promises of biomaterials that there’s a perception that these products might not actually work or may not be cost competitive. It’s important for people to know that they are working. I’ve been working with Sorona for 12 years. The product grew 30 percent last year. It’s being well-accepted by the market because it works and it’s cost competitive and has a great sustainability story. I’ve been asked this for the past dozen years, and I’m as or more excited now than I have been in the whole time I’ve been working here.

I think biomaterials have had some false starts and some small companies that have over-hyped what they were doing and then failed, but we are on the way to really having an impact. DuPont remains super-driven in this area; we’re investing in it and we really see it as an important focus for the future.