(7by) Polymer Process Design and Modelling to Fabricate and Understand Unique Composite Architectures

Research Interests: Soft materials, such as polymers, continue to play an increasingly important role in virtually all engineering disciplines. Understanding the complex interplay between synthesis, processing, structure, and properties of polymers is critical to make any substantial advances in fields where polymers play a dominant role, such as packaging, filtration, bio-scaffolding, and energy storage to name just a few. As a graduate student at Case Western Reserve University studying under Prof. LaShanda Korley I gained expertise in applying polymer processing technologies to achieve unique structures. While studying deformation mechanics in multilayer films, I wrote a successful Department of Energy experimental grant for synchrotron time at Brookhaven National Laboratory that led to multiple publications for not only myself, but many others in our department. One of these manuscripts highlighted the role of structural evolution during post-extrusion processing of poly(ε-caprolactone) (PCL) nano-fibers. We not only correlated this structural evolution to mechanical properties of the PCL fiber mats, but also the reduced efficacy of peptide modification of the fiber surfaces which substantially altered their use as tissue engineering scaffolds. I was also able to use existing multilayer fiber/matrix coextrusion technology to develop a one-step method to fabricate well-distributed, randomly aligned, sub-micron scale polyester fiber-reinforced poly(ethylene oxide) (PEO) hydrogels. By varying fiber loading, post-extrusion take-up, and fiber material type, I was able to substantially improve the mechanical properties of these hydrogels, reaching similar stiffness to articular cartilage. By manipulating the mechanical environment of the hydrogels, we also manipulated cellular response and differentiation when using the hydrogels as bio-scaffolds. This work highlighted the ability to use polymer processing technology and commodity polymers to address a substantial challenge in the biomaterials community. In addition to existing publications on this technology, we have also filed a US Patent application and I assisted with writing a National Institute of Health grant to continue this work after moving on to my post-doctoral fellowship position.

As a post-doctoral fellow at the University of Minnesota working with Prof. Chris Macosko and Prof. Frank Bates, I have developed a substantial knowledge base in polymer processing fundamentals and rheology. My current research is focused on understanding polymer-polymer interfaces. I have been able to utilize rheological and thermal transport modelling to better understand the relationship between processing parameters, molecular structure, and catalyst selection on adhesion between polyolefins. The observed interfacial weld strengths between polyethylene (PE) and polypropylene (PP) vary over ~2 orders of magnitude, based on these variables. Each interface was also characterized with a suite of microscopy techniques. Further, we have been able to connect these interfaces and morphology derived from various processing techniques (extrusion and molding) with the final mechanical properties of polyolefin blends. This work demonstrates the role of not only molecular structure but also process modelling to maximize adhesion between immiscible polymer pairs to achieve tailored interfaces with specific mechanical properties, and forms the basis for two manuscripts currently in preparation. As I continue on as an independent faculty member, I would leverage my lifelong passion and ability to design new systems to better understand fundamental concepts at the intersection of chemical, mechanical, and materials engineering.

Selected Publications (13 total, 5 lead author, 98 citations via Google Scholar)

1. Jordan, A. M.; Kim, S.-E.; Van de Voorde, K.; Pokorski, J. K.; Korley, L. T. J., In Situ Fabrication of Fiber Reinforced Three-Dimensional Hydrogel Tissue Engineering Scaffolds, ACS Biomater. Sci. Eng., 2017, DOI: 10.1021/acsbiomaterials.7b00229.

2. Jordan, A. M.; Viswanath, V.; Kim, S-E.; Pokorski, J. K.; Korley, L. T. J., Processing and surface modification of polymer nanofibers for biological scaffolds: a review, J. Mater. Chem. B, 2016, 4 (36), 5958-5974, DOI: 10.1039/C6TB01303A.

3. Jordan, A. M.; Marotta, T.; Korley, L. T. J., Reducing Environmental Impact: Solvent and PEO Reclamation During Production of Melt-extruded PCL Nanofibers, ACS Sustainable Chem. & Eng., 2015, 3 (11), 2994-3003, DOI: 10.1021/acssuschemeng.5b01019.

4. Jordan, A. M.; Korley, L. T. J., Toward a Tunable Fibrous Scaffold: Structural Development During Uniaxial Drawing of Coextruded Poly(ε-caprolactone) Fibers, Macromolecules, 2015, 48 (8), 2614-2627, DOI: 10.1021/acs.macromol.5b00370.

Teaching Interests: I believe that teaching in a university setting can be divided into three separate but related roles: individual mentoring, classroom instruction, and community interaction. The role of faculty members as individual mentors cannot be understated. As a graduate student and post-doctoral fellow, I have personally mentored 11 undergraduate students over multiple academic terms. Each of these students has contributed to the progress outlined above and have gone on to successfully fill roles ranging from technical sales positions to graduate students at academic institutions. In addition to working with undergraduate students, I have also had the opportunity to work with high school students from the Cleveland Metropolitan School District (CMSD). Working closely (5 hours per week over a 2 year period) with two different high school students in a laboratory setting provided them with hands-on experience working in a scientific role and allowed me to adjust my mentoring style to reach students at different points in their lives and educational experience. Both of these students are currently enrolled in 4-year university programs studying forensic science and biology. These experiences highlight my ability to effectively lead a research team while simultaneously working on an individual basis to help students find their own path in science, technology, engineering, and medical careers.

In addition to their role as mentors, university faculty must be excellent classroom instructors. During my academic career I have served as an instructor for laboratory classes emphasizing polymer characterization techniques for both undergraduate and graduate students. I was also given the opportunity to lead the introduction to polymer mechanics class during the summer offered to CMSD high school students participating in our Polymer Envoys program. As a classically trained chemical engineer, I would feel comfortable teaching core courses ranging from introductory level to transport phenomena. Having gained substantial expertise in soft materials processing and mechanics throughout my graduate career, I would also feel comfortable teaching any advanced courses in polymer rheology, physics, processing, and mechanics. I would also welcome the opportunity to combine these concepts to develop a special topics course with a focus on innovative processing strategies for large-scale production of functional soft materials. While teaching courses, university faculty are often called to serve the needs of the department as a whole. As a graduate student, I was responsible for training users, obtaining and interpreting data for difficult experiments, and repairing departmental equipment including tensile testing equipment (4 years), small/wide-angle X-ray scattering (3 years), atomic force microscope (3 years), and equipment in the thermal analysis laboratory (2 years); currently as a post-doctoral fellow, I am responsible for supervising the polymer processing laboratory.

Finally, as community support of scientific funding is increasingly crucial, I feel that it is our role to interact with our local communities and stress the importance of not only scientific research, but also scientific literacy. This can be accomplished through local coffee shop chats, where members of the community can ask questions of university personnel in a relaxed setting to better understand our day-to-day job functions and added value. We can also achieve this through outreach events at local schools with 1-2 events per semester. I have also led these efforts both as a member of the Korley research group as we travelled to K-8 schools in the Cleveland area and also as the president of the graduate student organization where I worked with the CWRU community to organize and host groups for outreach days such as “Introduce a Girl to Engineering Day”. While not the event organizer as a post-doctoral fellow, I have continued this commitment to community involvement as a participant in numerous outreach events at the University of Minnesota. This multi-faceted approach to education and community engagement along with a proven track record of contributing to the academic community in both research, teaching, and support roles makes me an ideal candidate for a faculty position.