Career: Damage Evolution In Polymeric Materials Undergoing Hydrolysis Or Photo-Degradation

This Faculty Early Career Development (CAREER) program supports fundamental research to improve the Nation's health by advancing the understanding of the combined effect of chemical reactions and mechanical deformation on degradation (material damage evolution) in polymers. As an example, for rEnvironmental Protection Agencyiring broken bone, knowledge of the evolving damage determines how the polymeric biomedical implant can provide proper support and commensurately degrade and absorb into the body, while a broken bone heals. Currently design engineers lack the information necessary to predict the load carrying capacity of degradable polymeric components and, therefore, the designs are not optimal. The results of this research will generate experimental data, mathematical models, and simulation tools that will uncover the relationship between chemical constituents and applied load on the degradation behavior of polymeric materials. That knowledge will enable improved engineering design in numerous applications where polymeric degradation occurs, thus advancing national prosperity and welfare along with scientific progress. The proposal includes an integrated education plan with several components, one of which is the development of new courses for undergraduate and graduate students at NJIT. The course material will also be modified and adapted into outreach programs for pre-college students through university-wide initiatives.The objective of this research is to bridge the behavioral knowledge gap currently limiting our predictive ability for polymeric materials undergoing degradation reactions due to hydrolysis or photo-degradation. Accordingly, the following research tasks are proposed: (i) Development of a pair of thermodynamically consistent, frame-indifferent, experimentally validated multiphysics constitutive theories for the behavior of soft materials undergoing hydrolysis and photo-degradation reactions. (ii) Experimentation on the industrially important and intellectually stimulating polymer PLA, under conditions that specifically probe the coupling between chemistry and mechanics in support of the constitutive effort and for validation purposes. (iii) Formulation of a new set of robust finite elements that couple large deformation implicit solid mechanics with reaction-diffusion systems and radiative traNational Science Foundation er. (iv) Integration of research and education to train and spark interest in students of all levels, from pre-college to graduate schools. This project will allow the PI to advance the knowledge base in mechanics of materials under multiple field effects?from modeling to computation?and establish a long-term career in mechanics.This award reflects National Science Foundation 's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.