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06/03/2015

Two chemistry students win IPRIME poster awards

Jacob Brutman and Suyue Chen were poster award winners at the recent IPRIME annual meeting.

Jacob Brutman
Jacob Brutman is a third-year graduate student advised by Professor Marc Hillmyer. His research interests include the development and improvement of healing cross-lined materials from renewable resources.

His poster and presentation: Crosslinked polymers with controllable healing characteristics have received significant attention over the last decade. However, there is still much to be developed with these materials in the sustainability arena. Herein, we studied the healing capabilities of crosslinked bioderived poly(lactones) through Lewis acid catalyzed transesterification reactions. Materials that use isodesmic reactions (e.g., transesterification) for healing are termed vitrimers and have been reported using a diverse range of chemistries. Our initial studies focused on the healing properties of amorphous star-shaped poly((±)-lactide) crosslinked with methylenediphenyl diisocyanate in the presence of stannous(II) octoate. These materials exhibited remarkably fast stress relaxation rates when compared with previously reported polyester-based vitrimers, and exhibited similar stress relaxation rates at temperatures 140 °C lower. Furthermore, the materials were able to recover their original tensile strengths post-healing by heating the system at 140 °C for only 30 min. These results will be described in this presentation, as well as our ongoing research efforts on utilizing renewable cross-linkers, a variety of Lewis acid catalysts, and other amorphous polyesters derived from substituted lactones.

Suyue Chen
Suyue Chen is a third-year graduate student advised by Professor Lee Penn. His research interests include metal nanostructure synthesis, nanomaterial characterization, nanomaterial-based electronic device fabrication and crystal growth.

His poster and presentation: Silver nanostructures have been the focus of intense research in the last few decades for their potential use in electrodes, surface enhanced Raman spectroscopy (SERS), antimicrobial materials, etc. Our eventual goal is to obtain silver nanowires (Ag NWs) with high purity and aspect ratio for their best performance in transparent conductive films (TCFs). Polyol synthesis is an effective method to make various silver nanostructures including Ag NWs. It is hypothesized that the size, morphology, crystal structure, and phase composition of silver seeds lay heavy influences on the final product in a polyol synthesis.  However, the understanding and control over silver seeds are hindered by the fast growth of these seeds in most polyol systems using elevated temperature. In this study, we proposed a mild polyol synthesis using room temperature under UV irradiation. Such reaction produced silver nanoparticles (Ag NPs) without subsequent growth, allowing a better investigation on such particles that can serve as seeds for further reaction.

Download a PDF with information about the award winners and their posters.