"Designer Functional Polymers For Energy And Optoelectronics"
University of Michigan
Alberta Innovates Engergy and Enviroment Solutions Lecture
Polymers have rapidly replaced metallic and ceramic materials in various applications due to their numerous advantageous properties including low weight, mechanical toughness, easy processability, low cost, corrosion resistance, and readily tunable physicochemical properties. However, their transporting properties for thermal energy and charge are rather not fully developed but limited so that applications that require efficient heat transfer and/or charge transport are the area in which polymers have yet to replace inorganic and metallic materials. In the first part of the seminar, I will discuss our recent effort for flexible solar cells and high performance plastic electronics by molecular design and directed self-assembly and alignment of conjugated polymers. The optical and electronic properties of CPs, such as absorption, emission, and conductivity, are highly anisotropic due to the 1-dimensional nature of the conjugated polymer backbone. These unique optoelectronic properties can be fully utilized in device applications only when the conjugated chains are aligned. We recently developed lyotropic liquid crystalline CPs and achieved nanoscopic and macroscopic arrangement and alignment and demonstrated more than 1600 times faster charge carrier mobility along the CP alignment direction than the perpendicular to the alignment direction in a thin film transistor (TFT).1 In the second part of my seminar talk, our recent development of high thermal conductivity in amorphous polymer thin films will be discussed. Recently, we demonstrated an order of magnitude enhancement in thermal conductivity of amorphous blends consisting of two hydrogen-bonding-capable polymers over a narrow range of composition fractions.2 We also revealed a strong positive correlation between thermal conductivity of polyacrylic acid (PAA) and its degree of ionization and established nearly one order of magnitude enhanced thermal conductivity in fully ionized PAA.3 These results suggest that significant gains are possible in engineering thermal energy transport property in amorphous polymer blends and homopolymer systems. If time allows, other functional polymer development projects will also be discussed.
Faculty Host: Dr. Hyun-Joong Chung
Jinsang Kim is a Professor of Materials Science and Engineering having a joint appointment in the Chemical Engineering, Biomedical Engineering, Macromolecular Science and Engineering, and Chemistry at the University of Michigan, Ann Arbor. He holds a M.S (1993) and a B.S. (1991) from Seoul National University, Korea, both in Fiber and Polymer Science. He earned his Ph.D. in 2001 in Materials Science and Engineering from MIT, where he studied the design, synthesis, and assembly of conjugated sensory polymers and energy transport properties in the controlled structures. He is also an expert in genetically engineered protein research. His postdoctoral work in this area at Caltech involved the expression of artificial genes to determine the extent to which artificial genetic information can be used to encode supramolecular assembly in macromolecular systems.
He has won several prestigious awards including 2016 Monroe-Brown Foundation Research Excellent Award, 2007 NSF CAREER Award, 2006 Holt Award for excellent teaching, 2002 IUPAC Prize for Young Chemist, 2002 ACS ICI Award. He was also named one of emerging investigators by the journal of materials chemistry in 2007. His current research interests at the UM are plastic electronics, self-signal amplifying molecular biosensors, highly emissive organic emitters, and high performance polymers. His research has been sponsored by NSF BES, NSF ECS, NSF DMR, AFOSR, ARO, DoE, NIH, ACS, KIMM, KRF, QIA, Qatar NPRP, Samsung, LG Chem, and Center for Chemical Genomics.