Master thesis: Designing a bottom-up computational approach for sustainable polymers

The document is a Master thesis presented and defended in September 2024 within the Master in Nanoscience and Materials Technology of University of Cádiz, Spain.

Abstract:

This work presents a detailed study of polycaprolactone (PCL), a biodegradable polymer with potential applications in biomedicine and additive manufacturing. The main objective is to adapt computational methodologies to analyse the relationship between the structure, properties and performance of this polymer, using molecular dynamics simulations.

The bottom-up approach, based on atomistic simulations, allows us to understand the influence of the interactions at the molecular level on macroscopic properties. An optimised force field to study PCL in different environments (vacuum, dissolution and melt) is developed, with special emphasis on the structural and dynamic behaviour of the studied polymer systems.

To understand this behaviour, two fundamental structural properties of polymers have been calculated: the radius of gyration, Rg, and the end-to-end distance, Re. Quantitative results have also been obtained for some properties, essential for the development of future models of the systems in melt: the density and the terminal relaxation time. The data have been compared and verified with data published in literature. The behaviour of the chains with different molecular weights is in agreement with the theoretical models.

This study aims to establish a basis for future work, in order to optimise the use of biopolymers in sustainable applications, such as 3D printing, by improving their performance and compatibility with industrial processes.