First-generation bioplastics were made from food crops like corn and sugar. A new biomaterials startup is using something very different: the autumn leaves collected by cities each fall.
The startup, Perennial Polymers , extracts the natural polymers in leaves—lignin and cellulose—to make plastic that can easily break down. It’s an approach that can ultimately be less expensive than making other bioplastics, the company says.
“I spent the last 12 years or so in the biomaterial space, and got to see from the inside how challenging it is, largely due to the economics,” says Nathan Noyes, founder of Perennial Polymers. “Two of the main reasons for that seemed to be that we were always relying on food-grade agricultural feedstock when moving away from petrochemicals, and the route to turn that into a plastic relied on fermentation, which is quite expensive.”
Urban leaves, he realized, didn’t require any agricultural land to grow, and there was already infrastructure in place to collect them. The startup, which works in a lab in Delaware, was inspired by previous academic research about the potential to use leaves to make new materials (like this study of maple leaves ). After launching this summer, Perennial developed its own new material with a process designed to easily scale up, and filed provisional patents.
The startup’s formulation includes not only lignin and cellulose, but minerals from leaves to strengthen the bioplastic. Production is designed to be low cost, both because of the cheap feedstock and because it doesn’t require the expensive step of fermentation. The plastic can be used in existing industrial equipment to make products.
One potential application is on farms, where huge plastic sheets are commonly used to reduce weeds and erosion. This plastic “mulch” helps increase farm yields, but also creates microplastic waste in farm soil. The plastic films currently in use can’t be recycled, and often are burned. A similar film made from Perennial’s material could safely break down in the field. “In very early testing in thin films, it looks like our material degrades in contact with soil over about two to three months,” says Noyes. That’s similar to the way leaves biodegrade in their natural state.
The material could also be used in packaging such as plastic mailers for products that have to be protected from the weather, or other uses where plastic serves a useful purpose, but can’t easily be recycled today, Noyes says.
Large cities like New York collect thousands of tons of leaves each fall. Leaves are often composted, but EPA data suggests that nearly a third end up in landfills, where they can’t easily break down. Perennial wants to tap into existing urban leaf collection systems to make its products, and although the company just launched a few months ago, a municipal partnership is already in the works. Other natural materials, including waste from the forestry industry, could also potentially be used to make the plastic.
The startup is scaling up to begin testing its material with customers, and aims to commercialize the bioplastic in 2027.
