Chemo-mechanical modelling of deformation and fracture in biodegradable polymers

Biodegradable polymers are eco-friendly and find use in various applications due to their ability to gradually break down once their purpose is served. They constitute a sustainable alternative to traditional plastics, especially in areas such as packaging, films, and coatings. They are also attractive materials in healthcare applications including implants, sutures, and drug delivery devices, thanks to their biocompatibility and adjustable properties. In these applications, biodegradable polymers must maintain their designed morphology and possess suitable mechanical properties (stiffness, strength, and toughness) before completing their structural function.
However, a major challenge in maintaining the performance of these polymers is their brittleness. In healthcare applications, the development of cracks can generate fragments that may result in complications and, in extreme cases, prove fatal. In sustainability applications, premature material fracture curtails the operational lifespan and diminishes overall performance. The chemical reactions that cause degradation (e.g. hydrolysis) can also create defects like voids and microcracks, and stress-assisted degradation can accelerate the rate of crack growth. This involves a complex interplay between chemistry and mechanics, not yet fully understood.
This project aims to develop a comprehensive chemo-mechanical continuum modelling framework to simulate the deformation and fracture by stress-assisted chemical degradation in biodegradable polymers. The continuum model will account for key aspects including the inelastic deformations of the polymer network, chemical reactions, and diffusion of reactants. It will be integrated into powerful computing tools for testing these materials under various loading conditions. The project will also explore how different environmental factors affect cracking and investigate various degradation pathways. Additionally, it will examine how the polymer's chemistry and structure...