FLO Materials Creates Infinitely Recyclable Eyewear, Commercializing Findings in Berkeley Lab Research

Manufacturing consumes two percent of U.S. energy to produce 300 million metric tons of virgin plastics annually. While packaging represents a very common application, plastics are also ubiquitous in what are called durable consumer goods—things like shoes, clothing, sporting goods, electronics, and eyewear. And while the circular economy, or the practice of designing products and their materials to remain in service as long as possible, could cut plastic’s climate impact and has become a key selling point for many brands, very few consumer goods are truly circular.

Many such goods marry multiple types of plastics, which cannot be easily separated and reused. Color is another circularity hurdle: Even products made of the same plastics but of different colors can’t be recycled together.

But a recent study in Science Advances describes successes that researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) have made in testing the infinite recyclability of a new class of plastics–even if the plastic is mixed with other materials, or if it is mixed with the same plastic but of different colors. 

One of the study’s co-authors, Peter Christensen, began work to commercialize this new type of plastic, called polydiketoenamine (PDK), in 2021, through FLO Materials, a startup that he co-founded with Kezi Cheng. The same year, Christensen and Cheng became Activate Fellows. They are part of our Activate Berkeley Community and are supported by Berkeley Lab’s Cyclotron Road, a Department of Energy Lab-Embedded Entrepreneurship Program. 

The co-founders have recently hit a key milestone toward developing a PDK-based product for FLO’s beachhead market: eyewear. 

“For products like eyewear, designers, brands, and consumers have high expectations for colors and patterns. Modern sunglasses and eyeglasses range in colors from crystal clear to complex multi-color patterns like tortoise shell. Because PDKs can be recycled in the presence of other materials, and we can remove the colors and then recolor the material in its next life, we can offer designers the same design palette that they have with virgin materials. Our goal is to help brands manufacture beautiful products for the circular economy, without compromising design.” says Christensen. 


 
While almost everybody has at least one pair of glasses or sunglasses, most people don’t know that the production of glasses frames can create up to 90 percent waste.
— Kezi Cheng

He and Cheng successfully created a set of eyeglass frames, made from PDKs, which can drop directly into existing manufacturing processes. This serves as an important proof point of the viability of using FLO’s material to create eyewear frames while using the same manufacturing equipment the industry already uses. Manufacturing eyewear frames is a complex process with multiple steps. Demonstrating that eyewear can be made also de-risks manufacturing for a broader category of products.

“While almost everybody has at least one pair of glasses or sunglasses, most people don’t know that the production of glasses frames can create up to 90 percent waste. Most eyeglass and sunglass frames are cut out of sheets of a plastic called acetate, and then the excess scrap produced in the manufacturing process is typically landfilled or burned for fuel,” says Cheng.

While some acetate could be collected and recycled, “doing so would not be economically or logistically feasible because the scrap would need to be segmented and recycled in small batches based on color, or because recycling and manufacturing systems are not co-located,” says Cheng. Furthermore, recycled acetate scrap has inferior mechanical properties to virgin materials. The PDK waste that is generated from frame production, however, could be collected and recycled with lossless aesthetic and mechanical performance, even if the material is a mix of colors, as the Berkeley Team researchers showed in their study.


We hope that the products we produce last forever and become heirlooms, but closing the loop in manufacturing waste will also allow us to collect broken or unused products from consumers and recycle them.
— Peter Christensen
 

What’s more, FLO Materials plans to create a system by which the lenses and metal components (hinges and temples), would be separated and could be then recycled, as well, making the full product infinitely recyclable.   

“We hope that the products we produce last forever and become heirlooms, but closing the loop in manufacturing waste will also allow us to collect broken or unused products from consumers and recycle them as well,” says Christensen.

For Christensen and Cheng, this is just the beginning. They are now scaling PDK production helping to close the loop for eyewear manufacturing, as well as other consumer-facing products. 

For more on that study and its broad implications for material circularity, check out the Berkeley Lab’s news release. For more information about FLO Materials, to inquire about partnerships or investment opportunities, visit its Activate profile or reach out to Christensen directly pete@flomaterials.com.