led to the development of the highly successful Vrentas-Duda free-volume theory that explains how the viscous behavior of polymer melts is coupled to the diffusional behavior in binary solutions. During this same period, Larry was granted a patent for a latent heat storage component in insulation to prevent the Alaska pipeline from melting the permafrost in summer.
In 1971, when Larry accepted a position as an associate professor of chemical engineering at Penn State, he began a long and remarkable academic career. In 1975, he was promoted to professor, and during 1978–1979, was a visiting professor at the National Taiwan University. For 17 years, he served as department head, retiring from that position in 2000. From 1990 until his death in 2006, he was co-director of the Center for the Study of Polymer-Solvent Systems. Unlike most administrators, however, he continued to teach courses and maintain a strong focus on his research and his students.
Working with his longtime colleague Jim Vrentas, he extended the free-volume theory and developed experimental techniques and methods of analysis to determine accurate diffusivity data over the wide range of temperatures and concentrations in polymer processing. Larry also developed a micro-reactor technique to study the thermal and oxidative degradation of lubricants under conditions that simulate many engine environments. In the course of his career, he published nearly 200 articles in refereed journals, 45 refereed proceedings, and 18 chapters in books.
Undoubtedly, he most enjoyed working with students. He collaborated with 70 master’s degree students, 45 doctoral students, and innumerable undergraduates in the classroom and the research lab. Larry was not the kind of advisor who would send his students off on their own. He worked closely with them, pointing out possibilities, challenging them, and molding their attitudes and approaches to research. The results of his mentoring are apparent in the success of many of his students in industry and academia.
Larry’s peers honored him with many awards. In 1981, the American Institute of Chemical Engineers presented the William H. Walker Award to Larry and Jim Vrentas for