Department of Chemical and Biological Engineering

To develop an understanding of how a composite influences structure, Eric Cochran is attaching block copolymers to a material that has extremely high surface area particles—clay. His work will help identify important parameters and adjustments for researchers as they work to create certain structures using different polymer properties.

Unlike traditional studies of composites, however, Cochran is working at the nanoscopic level. At this level, small property changes can have a large impact due to the high surface to volume ratio of nanocomposites. His research has the potential to improve the process scientists and engineers use to develop structures, and it recently received support from the National Science Foundation (NSF).

Cochran, an assistant professor in chemical and biological engineering, received a NSF CAREER award for his project “Block Copolymer Layered Silicate Nanocomposites: Thermodynamics, Dynamics, and Structure Property Relationships.” NSF gives CAREER awards in support of the early career-development activities of tenure-track assistant professors that most effectively integrate research and education within the context of their organization's mission.

“Receiving a CAREER award is an honor and a privilege,” he said. “I’m excited about this work. It’s not often that you can find something new to research in engineering, and this project will help build the foundation for future research projects.”

A new class of polymer composites

Underlying Cochran’s experience as a researcher is an interest in block copolymers, or what he calls the building blocks of new materials. “I uncover the basic mechanisms that cause polymer chains to change and react,” he said. “Knowing this fundamental science is important for more advanced applications.”

His newest project takes water that is naturally stuck to the surface of clay particles and replaces it with chemical groups that can cause polymers to form, essentially growing block copolymers directly from the surfaces of the clay.
The tough chemical structure of clay makes it a good candidate to begin research in this area. “The strength of the material can be imparted to the polymers, which will wrap each clay particle,” Cochran says. “Since block copolymers tend to self-organize, the clay particles will move with it, allowing us to precisely engineer where clay goes using synthetic techniques.”
An early passion for polymer research

Cochran began engineering research as an undergraduate at Iowa State, working on a composites project with a materials science faculty member. This work led him to a summer Research Experience for Undergraduate (REU) at MIT, which also focused on polymers.

From there, he attended the University of Minnesota, where he began building a foundation of theory to expand his research efforts, while also incorporating practical applications into his thesis project.

“I really enjoyed combining polymers to develop structures during experiments, but I was looking for something to complement this work,” he said. “That’s when I gained an appreciation for the theory behind the research, and I began balancing the two aspects of my work.”

Next up for Cochran’s career was a two-year postdoc position at the University of California at Santa Barbara, working under Glenn Fredrickson, one of world’s top polymer theorists. During this experience he concentrated more so on learning the theoretical aspects of polymers, which influenced his current research direction.

Making new materials

With a long-time interest pushing him to new boundaries in polymer research, Cochran’s NSF-funded project will help establish what types of structures are optimal for specific applications.

“First we will build an understanding of how molecular design leads to a certain structure,” he explained. “Then from the other side, we look at what properties we want a structure to have. The entire process is like a feedback loop, with each step informing the next and impacting how we approach the design for the final material.”

One area that could benefit from this work is the packaging industry. Cochran’s work could lead to a cheaper material that adequately meets the packaging requirements of sensitive products such as electronics and medical devices.