10:30 - 11:00 a.m. Coffee with speaker | 11:00 a.m. - 12:00 p.m. Seminar
"Combining Plastics: Semicrystalline Multiblock Architectures Enhance Polymer Blend Properties"
James M. Eagan, Associate Professor, Department of Polymer Science, University of Akron
Abstract: Of all commercial plastic, nearly two-thirds consist of polyethylene (PE) and isotactic polypropylene (iPP). Recycling of these two materials is complicated and costly due to challenges in sorting polyolefins from one another as well as the physical phenomenon of phase separation and poor interfacial adhesion. In this talk, we will share our catalytic system capable of synthesizing block copolymers of iPP and PE is presented along with the properties these materials exhibit when added to PE/iPP blends. The effects of molecular weight and block copolymer architecture on interfacial adhesion and compatibilization will be discussed. For example, iPP-b-PE copolymers improve adhesive forces between Ziegler-Natta grade HDPE and iPP to the extent of cohesive PE failure, similar to the properties observed in metallocene grade LLDPE/iPP (hot-tack polyolefins). The block copolymers further improve mechanical tensile and impact performance of PE/iPP blends when added as a third component in small amounts (<1 wt%). A proposed mechanism of adhesion will be discussed along with the potential for enhancing the recyclability of plastic waste. Following on this work, a non-living polymerization method for producing polyolefin multiblocks has been discovered. This synthetic method relies on pre-forming telechelic PE and iPP before linking them together in randomly arrange “shuffled” block copolymers. These molecules also act as efficient compatibilizers, but also open the possibility of selectively tuning the crystallinity, density, and composition of the blocks while significantly improving the industrial scalability of multiblock synthesis.
Bio: James M. Eagan is an associate professor at the University of Akron School of Polymer Science and Polymer Engineering. He received his Ph.D. from Columbia University in 2014 under the guidance of Scott A. Snyder and completed postdoctoral studies at Cornell University under Geoffrey W. Coates. He is the recipient of an NSF Career award, the AAAS Newcomb Cleveland Prize, and is a senior fellow of the national academy of inventors. He serves on the advisory boards of the Akron Polymer Industry Cluster, several startup companies, and ACS Applied Polymer Materials.