Plastics are fundamentally linked to energy and the environment. They are derived primarily from crude oil. Per pound, making plastic from oil uses more energy than making iron, steel, glass and paper, though the use of plastic instead of those materials can save energy. Plastics emit a lot of greenhouse gases when produced, recycled and incinerated. Most plastics are not biodegradable, so what is not incinerated or recycled is discarded as waste throughout the environment.
“As the Woods Institute and Precourt Institute look toward integration into Stanford’s new school focused on climate and sustainability, we are keen to partner on important topics where our mandates and communities overlap. Reinventing plastics is a compelling topic,” said Chris Field, director of the Woods Institute and a senior fellow of the Precourt Institute.
“Plastics are a useful component of modern life, but we need to make them more sustainable. This huge challenge requires a holistic approach,” explained Field, who is also professor of earth system science and of biology.
While the Woods Institute has funded some research on plastic’s problems and potential solutions, the topic is fairly new for the Precourt Institute.
“The institute has always supported research to generate and use energy more sustainably, and we’ve worked with Woods a great deal, but this was our first call for proposals on a specific industry,” said Yi Cui, director of the Precourt Institute and a senior fellow of the Woods Institute.
The new research grants are the second set of Precourt Pioneering Projects.
“This new program and additional new research programs we’re developing will partner with other Stanford entities to create interdisciplinary research teams to overcome large, complex challenges in energy and the environment,” said Cui, who is also a professor of materials science and engineering, and of photon science at Stanford’s SLAC National Accelerator Laboratory.
All three of the new research projects will run for two years with funding of $200,000 to $225,000 per year each. Together, the projects will support the education, research and living expenses of nine graduate students and postdoctoral scholars, as well as the material and supply costs of the research.
One project reimagines manufacturing for plastic car components, which are growing in use due to light-weighting trends for fuel efficiency and electrification. The research team will leverage the revolutionary new approach to 3D printing called “continuous liquid interface production,” developed by team member Joseph DeSimone, professor of chemical engineering and of translational medicine. Researchers hope to create circular, additive automotive manufacturing coupled with new chemistry and reactive recycling process strategies.
“This work has the potential to enable circular economies in automotive materials,” said the project’s principal investigator, Robert Waymouth, professor of chemistry. “We aim to simultaneously develop new chemistries and new 3D printing techniques to re-imagine how plastic automotive parts are designed, manufactured, and recovered at the end of their useful life.”
The third investigator on this project’s team is William Tarpeh, assistant professor of chemical engineering.
Another new project aims to solve challenges in plastics recycling and upcycling, (recycling to a higher value material), by garnering a deeper understanding and control of the design and microstructures of polymers from the molecular to the bulk length scales. Specifically, researchers will try to establish the missing link between bond dynamics and macroscopic properties of a new class of plastics consisting of dynamic polymer networks. The bonds of DPN plastics are reversible. This reversibility can enable their upcycling and reduce waste generation.
“These advantages over single-use polymer networks could enable sustainability efforts worldwide, including packaging, textiles and construction. This research could also seed the growth of new technologies, including battery coatings, photovoltaics, electronic skin, portable power and soft robotics,” said the project’s principal investigator Zhenan Bao, professor of chemical engineering.
Bao’s co-investigators on this project are: Wei Cai, professor of mechanical engineering; Jun-Sik Lee, a lead scientist at SLAC; Mengning Liang, staff scientist at SLAC; and Jian Qin, assistant professor of chemical engineering;
The goal of this project is to reduce plastic waste from three-dimensional printing by developing a reusable 3D printing resin that can be printed, bulk erased and re-printed over numerous cycles. This will be enabled by orthogonal polymerization and depolymerization photo-chemistries that are triggered by distinct wavelengths of light. These chemical processes will be uniquely enabled by nanocapsules that are triggered by low energy light at longer wavelengths.
“The 3D-printing market is growing at a dizzying pace, yet the vast majority of materials are discarded after a single use, with most materials recyclable only through the use of expensive and specialized equipment,” said this project’s principal investigator, Dan Congreve, assistant professor of electrical engineering. “Using these nanocapsules allows us to access new recycling methods that could allow these materials to be recycled many times.”
“It is our goal to generate prints from recycled resin that have comparable physical properties to those of prints from fresh resin.” added Danielle Mai, assistant professor of chemical engineering and co-investigator on the project.
The urgency of climate and sustainability challenges facing the planet drove Stanford to align and expand its research and education resources for greater impact. The new school brings together and expands the School of Earth, Energy & Environmental Sciences, the Precourt and Woods institutes, the facilities at Hopkins Marine Station and the department of Civil & Environmental Engineering joint with Stanford’s School of Engineering. It will also include a new Sustainable Societies Institute and a Sustainability Accelerator.
Within the new school, Woods, Precourt and the new institute will bring faculty from across all Stanford schools together around challenges that require multiple perspectives, such as finding alternatives to current plastic use. They provide an open door to faculty and students who want to engage in climate and sustainability scholarship and impact, but aren’t members of departments or degree programs in the new school. The Sustainability Accelerator will draw on expertise from across the university and outside partners to co-create and scale policy and technology solutions for sustainability challenges.