Polymer Surface Topography in Life Science Applications: Impact of Manufacturing and Environmental Factors
Time: Fri 2024-10-04 09.00
Location: Kollegiesalen, Brinellvägen 8, Stockholm
Video link: https://kth-se.zoom.us/j/64926682181
Language: English
Subject area: Fibre and Polymer Science
Doctoral student: Álvaro Morales López , Polymerteknologi
Opponent: Dr Candice Majewski, University of Sheffield, England
Supervisor: Professor Anna Finne Wistrand, Polymerteknologi
QC 20240906
Abstract
The Life Sciences industry is leading the fifth industrial revolution, driving manufacturing towards precision, personalization and circularity through the implementation of additive manufacturing (AM). Since its origin in 1983, AM has enabled the fabrication of complex components previously inconceivable through conventional manufacturing techniques. In particular, powder bed fusion and material extrusion techniques have been adopted for their versatility with polymeric materials and ability to produce components meeting bioprocessing, biopharmaceutical and tissue engineering requirements.
Despite its potential, integrating AM in the Life Sciences presents crucial challenges, particularly due to the complex surfaces produced through the layer by-layer fabrication process, which result in rough surfaces and affect the functionality of the printed components. Traditionally, surface texture is characterized by contact stylus measurements employing profile roughness parameters such as the average roughness (Ra). However, the use of the Ra parameter is insufficient, as it fails to capture essential 3D topographical features and spatial variations.
This thesis addresses these challenges through two main research phases. First, it develops a comprehensive characterization workflow for polypropylene surfaces fabricated by conventional manufacturing, powder bed fusion and post-processing techniques. By implementing advanced roughness analysis, this research presents a deeper understanding of surface properties, such as texture and wettability, and their impact on essential bioprocessing applications, including cleanliness, bacterial adhesion, and biofilm formation.
The second phase extends this methodology to analyze environmental and sterilization effects on the surface properties of three dimensional-printed scaffolds. These platforms, made from degradable polymers, are intended for soft tissue engineering and regenerative medicine applications. The research examines how different thermal conditions and sterilization processes affect the surface texture and, consequently, the thermal and physical properties of the scaffolds.
The findings contribute to optimizing AM technologies for clinical and bioprocessing applications, providing a roadmap for future innovation. By emphasizing interdisciplinary collaboration, this thesis emphasizes the necessity of bridging materials science, engineering, and biology to create effective solutions for societal challenges.