For Christian Nowak, the knowledge of objective permanence provided by the natural sciences sparked a life-long affinity for the subject. “English was my second language while growing up, which meant that I’d occasionally have difficulty interpreting certain linguistic idiosyncrasies or explaining concepts relating to the social sciences,” says Nowak.
“With the physical sciences and mathematics, however, misinterpretation was never an issue, because the fundamentals never change. Two plus two will always equal four, and I find myself drawn to this objective understanding of our world,” Nowak continues.
Having graduated from the Rensselaer Polytechnic Institute in Troy, New York, Nowak found Cornell University’s multifaceted chemical engineering graduate program the most conducive for exploring his varied scientific interests. Toward the end of his first semester at Cornell, Nowak joined the Fernando A. Escobedo lab, Chemical and Biomolecular Engineering, a research group specializing in what Nowak describes as his favorite area of research—polymers.
“When Professor Escobedo initially discussed the lab’s work on polymers with me, I found the research very pertinent to my interests. I also knew that, as soon as I had acquired a basic understanding of computer coding, I would be ready to contribute.” Moreover, Nowak explains, he and Professor Escobedo work well together, which he reasons is a big factor in his success as a graduate student.
New Materials, From Virtual Simulation to Virtual Experimentation
At the Escobedo lab Nowak and his lab members utilize computer simulations to create virtual models of molecular behavior and identify potential materials that could represent significant improvements on current materials. Upon analyzing the trove of data produced by the virtual simulation, if Nowak determines that a material has demonstrated potential in a certain function and can be feasibly produced, the composition of the material is conveyed to experimental collaborators. The virtual experimentation method employed by the Escobedo lab, Nowak explains, follows in the spirit of the nationwide Genome Project initiated during the Obama presidency.
“The plan is to generate newer, better performing materials for everyday functionality and to do it quicker through computational methods, which can severely shorten the timeline of innovation.” Consequently, Nowak says virtual experimentation is shortening the time between origin and operationalization of materials from years into months.
Virtual experimentation, however, is a complex process with the most salient challenge being to develop and verify a virtual model that can properly represent the material behavior. “We essentially simulate a material by creating different versions of it—each with slight tweaks that we think will impact the behavior of the material—and by determining the most efficient version. Using molecular dynamics simulations, we can test molecular behavior under various stress factors including deformation and temperature cycling," says Nowak.
Owing to the need to create highly realistic models, Nowak’s virtual simulations are naturally extensive, with some materials’ models taking months to complete the simulation phase. “Because a simulation can run for extremely long periods, it’s essential to get the specific details correct when formulating a virtual model.”
Innovating New Polymers
Nowak primarily works on two types of polymers. The first, elastomers, comprise rubber-like plastic. The newer materials Nowak is currently researching are similarly stretchable compared to traditional rubbers. The new materials, however, possess far more strength. According to Nowak, these materials demonstrate great potential for a wide range of functions, from shock absorbers in vehicles to foam inside an American football helmet.
“Silicone, the present material used in manufacturing most solar cells, is usually preferred because it’s relatively inexpensive. But it’s also commonly accepted as being quite inefficient. These materials could potentially replace silicone.”
Nowak’s other area of focus comprises electronically conducting polymers. Unlike regular plastics, these polymers possess a distinct chemical composition which allows them to conduct electric charges along them. An example of such polymers’ functionality can be utilizing them to create solar cells.
“Silicone, the present material used in manufacturing most solar cells,” Nowak explains, “is usually preferred because it’s relatively inexpensive. But it’s also commonly accepted as being quite inefficient. These materials could potentially replace silicone. It will cost a similar amount, but will provide substantially greater functional flexibility, and its organic composition will also render it safer for use.”
New Polymers for Healthcare
According to Nowak, the most promising sector for harnessing electronically conducting polymers is a new aspect of healthcare bio-interfacing. A lot of essential, as well as occasional, body processes require electronic signaling—the release and reception of ions. These signals, Nowak explains, can be monitored through the use of the aforementioned polymers, thus allowing doctors to diagnose and treat patients in a far more comprehensive manner. Such polymers have great potential to be incorporated into conventional healthcare, demonstrating what Nowak characterizes as an important link between his research and its impact.
“Graduate scientific research such as ours always demonstrates an inherent tension between purely academic research and commercial-oriented studies. I, like most researchers, have an affinity for the academic nature of research. But I also prefer to retain the link between my virtual models and their real-world applications.” Nowak graduates at the end of the 2019 spring semester.