Advanced microstructures based on poly(trimethylene carbonate) : microfabrication and stereolithography

Abstract

There is an evident need in the biomedical field to develop (new) materials with tailored properties for specific applications. In addition it is essential to be able to process these materials into desired two- and three-dimensional shapes and (micro)structures. Microfabrication, and especially soft lithography, allows the creation of two-dimensional microstructures with features having size scales that match the dimensions of microorganisms and of individual cells of more complex organisms. Using twodimensional microstructured surfaces, investigations in the biomedical field involving cells, proteins and other biomolecules have been successfully conducted. Examples include microfluidics-based biological systems, microarrays and tissue engineering applications. Tissue engineering requires a three-dimensional scaffold, and multiple layers of two-dimensional microstructures have been stacked to realize this. However, significantly more reproducible three-dimensional structures can be obtained by stereolithography. This rapid prototyping technique allows creating designed scaffolding structures at high resolutions of upto 20 m. Unfortunately, most resins available for stereolithography do not yield the flexible and elastic biodegradable network materials that are required for the engineering of soft tissues or organs. This thesis describes the development of poly(trimethylene carbonate) (PTMC) macromers, their formulation into photo-crosslinkable resins and their processing into designed flexible and elastic creep-resistant structures.