Technical Abstract: The Chemical Catalysis Program supports the efforts of Professor Li Jia of the University of Akron for the investigation of the cobalt-catalyzed, carbonylative polymerization of heterocycles (e.g., aziridines) and heteroalkenes (C=O and C=N bonds). The research focuses on understanding the mechanisms of these processes and developing efficient synthetic methods for preparing both commodity and functional polymers. The process, which could lead to new classes of aliphatic polyesters, remains unexplored. The key to realizing the polymerization appears to be the activation of the acyl-cobalt bond. Nucleophilic and bifunctional organic co-catalysts with nucleophilicity and latent Lewis acidity will be used to accomplish the metal-carbon bond activation. The polymerization reactions developed in this project are powerful tools for the synthesis of tailor-made polymers for biomedical materials and environmentally friendly plastics.
The Chemical Catalysis Program supports the efforts of Professor Li Jia of the University of Akron for the investigation of novel, catalytic copolymerizations of aldehydes and carbon monoxide (i.e, the carbonylative polymerization of aldehydes). The research focuses on the rational design of catalytic cycles that utilize inexpensive starting materials derived from non-petroleum sources. This high risk research effort may result in the high reward, commercial development of degradable polymers. The products of the reaction, aliphatic polyesters, have a wide range of applications as specialty and commodity plastics. The research activity trains students and postdoctoral associates at the interface of organic, inorganic and polymer chemistry.
According to the US EPA, 30 milion tons of plastic waste was generated in 2010, and only 8% of the waste was recycled. Most of the plastics produced today have a very slow rate of degradation in the environment. Accumulation of the plastic waste posts a significant threat to our environment. This project aims at developing a method, i.e., carbonylative polymerization of aldehydes, for producing plastics that can degrade at a desirable rate in the environment after they serve their function as packing, engineering, adhesive materials, etc.. In addition, the method uses carbon monoxide, which is available from industrial waste streams and gasification of renewable carbon feedstocks, as a raw material. This further reduces the environmental footprint of the plastic. In the EAGER grant period, the researchers have probed two likely venues in an effort to realize the proposed route for producing the environmentally friendly plastics. One venue utilizes a cobalt-based catalyst system and has proved to be infeasible. The second venue uses a new catalyst design featuring ionic nickel complexes. The nickel catalysts have proved very promising. Preliminary results for the catalyst to catalyze a related reaction are positive. The researchers are continuing with the improvement of the catalyst to eventually realize the proposed polymerization.
