This grant will focus on investigating the erosion of degradable polymers subject to the concurrent actions of mechanical force and a reactive environment. Degradable polymers have recently attracted increasing attention for their great potential of reducing polymer waste and diverse biomedical applications. In practice, degradable polymers often carry mechanical load during their degradation. As a result, the mechanical force will inevitably influence the erosion process of degradable polymers, and the degradation process will also gradually change the polymer's mechanical properties. Despite its importance in applications, the understanding of the interplay between mechanics and chemistry in degradable polymers has so far been extremely limited. This research program aims to use both experimental and theoretical approaches to investigate the fundamental science governing the erosion of degradable polymers under complex chemical and mechanical actions. This research will contribute to the intense global effort to develop new degradable polymers for reducing polymer waste as well as the incessant exploration of new biodegradable polymers for novel biomedical applications. The impact of the project will be further broadened via the integrated education and outreach programs including interdisciplinary education and training opportunities to graduate and undergraduate students, internships for disadvantaged, first generation high school and college students in the greater San Diego area and a STEM program for academically-advanced 7-10th grade students from nationwide.
The specific goal of the research is to discover the chemo-mechanical coupling effects in degradable polymers during its erosion. The research objectives of this project include: (a) establishing a new theoretical framework for predicting the time-dependent behaviors of degradable polymers during the erosion process;(b) creating a new model for predicting stress corrosion cracking in degradable polymers;(c) uncovering how applied stresses may affect the erosion modes of a degradable polymer (i.e., surface erosion vs. bulk erosion);(d)revealing the effects of applied stress on the morphological change, induction time and front propagation speed of degradable polymers during the surface erosion process. The project will create new knowledge of the interplay between chemistry and mechanics in degradable polymers, thereby laying the foundation for quantitatively predicting the chemo-mechanical behaviors of degradable polymers and designing new degradable polymers for diverse applications.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
