Plastic is here to stay. Can we make it more sustainable?

Bradley Olsen, a professor of chemical engineering at MIT and a 2020 principal investigator at the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS), whose work focuses on developing biopolymers that can compete from a material and cost perspective with petroleum-based polymers, discusses the challenges and opportunities for a bio-based plastics market. Bradley says, “We need things like clothing, health care, shelter. The idea is to provide for those needs with the best materials solution.”


Plastic is a material of possibilities. It can hold groceries and take photographs; it constitutes ski coats and desk chairs and toothbrushes and suitcases. It can do all these things with the same basic building block—polymers, which are hefty strings of molecules. Whether a polymer becomes a rigid suitcase or a thin sheet of Saran wrap depends on the type of polymer, the chemicals that are added, and the way it’s cooked up into the final product.

This diversity is what makes plastic so cool and versatile and successful. But that success is one of the reasons we’re now facing a massive plastic pollution crisis. We rely so heavily on plastic that the current amount on the planet weighs more than all land and sea animals put together. Microplastics have been found in human blood and breastmilk, Antarctic snow, and rain. Of the thousands of chemicals added to plastics, about one-third of them remain poorly understood. And the wide range of components in plastic—the diversity that makes it such a useful material—is also what makes it really hard to recycle, contributing to the plastic pollution crisis we’re in today, says Costas Velis, an international expert on the circular economy of plastic.

The plastic problem has gotten so bad that last year more than 170 countries came together to discuss writing a treaty like the Paris climate accords but for plastic. Many experts say that the treaty needs to focus on reducing plastic production. But while this is an important goal, the idea that we’ll just stop needing plastic is “total wishful thinking,” says Velis. “Historically, we’re just producing more and more plastic, because it’s affordable and because it gave us functionalities that we didn’t have.” In fact, plastic production is on track to almost triple by 2060. And the treaty is facing a “coordinated campaign” by the petrochemical industry to slow progress, as seen during the latest negotiations in Nairobi, Kenya, earlier this month.