Polymers, a type of giant molecules with high molecular weights, are found in many facets of everyday life that utilize plastics, rubbers, resins, and foams. To provide robust and affordable polymer materials, one thrust in polymer chemistry is to develop efficient and inexpensive polymerization method that can prepare well-defined polymers with precisely controlled structures, compositions and dimensions. These polymers could be translated into functional materials for specific applications, such as self-healing materials, nanocomposites, coatings, lubricants, microelectronics and nanomedicines. In this project, funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Division of Chemistry, Professor Haifeng Gao at the University of Notre Dame develops a facile one-pot one-batch polymerization method that can prepare functional polymers with highly branched structures and very narrow size distribution. The research program is integrated with an education plan to develop undergraduate-level polymer courses and outreach activities (which including an annual Notre Dame Soft Materials Symposium and Science Fair) to stimulate academic-industrial collaboration and to engage the participation of local high school students and teachers.
This research seeks to develop a conceptually new polymerization method that applies the copper (Cu)-catalyzed azide-alkyne cycloaddition (CuAAC) polymerization of ABm (m is greater than or equal to 2) monomers to form polytriazole-based hyperbranched polymers in one pot. An important feature of this method is the confinement of the Cu catalyst within each hyperbranched polymer molecule, resulting in a chain-growth polymerization mechanism with a linear increase of polymer molecular weight and decreased polydispersity with reaction conversion. In addition, the dangling B group in the linear unit is expected to demonstrate higher reactivity than those in the terminal unit, resulting in a fast conversion of linear unit to dendritic unit in hyperbranched polymers and ultimately achieving a high degree of branching. The research activities provide hands-on laboratory training to the graduate and undergraduate students at Notre Dame in organic synthesis, polymer chemistry, and various characterization techniques. The students are developing presentation skills targeting both expert and non-expert audiences. The broader education and outreach impacts are magnified by: 1) improving the impact of current and new polymer chemistry topics in the undergraduate and graduate curriculum, 2) lecturing at local high schools to raise the public awareness of advanced polymer materials and nanotechnologies, and 3) organizing an annual Notre Dame Polymer Materials Symposium to stimulate academic-industrial collaborations and engaging the participation of high school students and teachers in a local science fair.
