Cellulotech, a Canadian materials science company, says it has developed a food-approved process that makes paper products resistant to water, grease, oxygen and steam – while having no effect on recycling and composition. To learn more about this potential alternative to plastic coatings, waxes and PFAS, we spoke with the company’s founder and CEO Romain Metivet.
Could you introduce us to your innovation?
Chromatogenesis is a reaction of green chemistry that grafts long-chain fatty acids onto various substrates such as paper, starch, PVOH, minerals, etc. to make them superhydrophobic, while preserving their repulpability and composting properties.
In addition to strong and durable barriers and its environmental benefits, the process is extremely cost-competitive. We use only 2 mg of reagent per square meter of specific surface area. Then 20 mg is needed for a substrate with 10 square meters of specific surface area per geometric square meter. One kilogram of such a reagent costs less than 10 euros, so the entry price per square meter is ultimately less than 0.02 cents. It is difficult to find something more competitive.
What is important to understand is that it is very different from the coating – it is a chemical reaction. We do not add a layer of different material on the surface of the substrate, but we generate permanent ester bonds on its entire specific surface. The products treated with chromatogenicity are monomaterials, not composites, and as such cannot be altered by layering or cutting.
The contact angles are well above the 90 ° limit (in some cases can even reach 180 °), which completely inhibits any capillary uptake. These ester bonds are basically permanent, and the paper that was treated two decades ago still shows the same properties today as it did then.
Chromatogeny not only has the potential to solve many of the problems facing the packaging industry in terms of cost and sustainability, but also to expand the use of paper to other industries. Our planet is a giant organic pulp mill and our main belief is that we should use it as much as possible in our economy.
What is the story behind the invention and commercialization of the solution?
More than a hundred years ago, it was discovered that paper could be made hydrophobic with the help of long-chain fatty acids. However, this process involved solvent, complex conditions and took days.
Twenty-five years ago, Daniel Samhain, now chief scientist at Cellulotech, discovered a new process of solvent-free green chemistry that was able to do this much faster and called it chromatogeny. Since then, the environmental and barrier properties of this technology have been well studied and even published in peer-reviewed journals. However, it may have been too early, and the first pilot developed more than a decade ago was insufficient in terms of speed and efficiency, which we believe has limited the adoption of this technology so far.
Two years ago, Cellulotech was founded to start from scratch and develop a scalable process. Instead of adopting a traditional engineering approach to paper or printing, we used chemical engineering. The new process we have developed brings a response time from a few seconds to just 0.1 seconds. As our graft yields also increase, we can use fewer reagents and solve other problems that have been encountered in the past. In addition, we are not limited by the roll-to-roll approach and can process whole sheets of corrugated cardboard and some 3D shapes.
We have patented this new process and intend to license it, as well as produce some materials for niche applications. We are now finalizing our industrial pilot plans with several partners to demonstrate the scalability of this solution.
Generally speaking, what are the key applications for Cellulotech and what sets it apart from conventional alternatives?
The applications are extremely diverse, as this chemistry can offer a wide range of barriers and strengths, which offers us the opportunity to optimize the productivity / cost ratio. In fact, we discover new applications quite often. I will mention the main ones we are focusing on at the moment.
In food packaging, grafted PVOH can replace PE coatings in disposable food packaging, such as paper cups, as well as eliminate PFAS. It is already approved for food contact in some jurisdictions.
For non-food packaging, as we see a high demand for “paper”, graft paper offers great durable properties that could help switch from plastic packaging such as those we see for paper towels or toilet paper, for example, or be used for All kinds of plastic-free packaging for e-commerce. Grafted cardboard for frozen foods is also a big potential market for us.
The ability to make superhydrophobic corrugated cardboard is also extremely interesting, as it can help save pulp, but also get rid of things like paraffin for demanding applications. It also opens up a new world of possibilities for this great material in construction or manufacturing. There is also potential for labels, as grafted PVOH can be used as repulpable release paper.
Generally speaking, chromatogenesis also has the potential to get rid of the “creep” phenomenon during storage, which loses huge amounts of packaging and goods every year.
Beyond the packaging, because the grafted paper behaves like “top-tex”, we have shown that it can be used to make 100% paper face masks or to offer selective oil absorption to remove oil spills, for example. We also research applications with textiles and wood. This is a whole new world of organic products that is opening up to us and it is very exciting.
Let’s talk about the end of life – does the material affect the recyclability of the materials on which it is applied? Will coated paper packaging still be recyclable within existing paper waste streams?
Due to the process and the small amount of reagent used, any substrate that is initially repulpable and compostable will remain re-compostable after grafting into existing waste streams. In addition, the grafted molecules are esters of fatty acids, something completely natural that we find all around us, which is completely harmless to the environment.
What does the future hold for Cellulotech?
At the moment, our goal is to finalize our partnerships and the funding of our pilot. While under construction, we will continue to work on product development projects with various corporate and academic partners and will continue to develop our intellectual property portfolio, especially in terms of new substrates and applications.
Once the pilot is ready and running at 500 meters per minute or more, scalability will be demonstrated and we will be able to start producing niche organic products, conduct larger tests and start licensing this technology. We expect our machines to be commercially available within two to three years.