Structural characterization of solid cellular polymers by X-ray tomography and light scattering

Authors: Saul Perez-tamarit (University of Valladolid)
Co-authored by industrial partner: No

Type: Thesis

State: Published (Approved)
Published: November 2019

Abstract: Study of cellular materials from a radiation-matter interaction point of view. The materials studied correspond to the group of micro and submicrocellular foams, as well as nanocellular foams, which comprise the most promising materials within this field of research due to their large applications. The peculiar characteristics of these new materials (in particular the very small cell sizes, below the micron and the extremely small cell wall thicknesses, of the order of tens of nanometers) make it necessary to develop new characterization methods and / or adapt the current ones in order to obtain accurate information about the mechanisms that take place during the manufacturing process and their cellular structure. In this investigation we will focus our attention on the development of techniques based on the radiation-matter interaction to analyze these systems. It is important to mention here that these techniques have been used very little in this type of materials, which will make the research to be novel and of great interest to the scientific community that works in the field of cellular materials. In particular, two great techniques have been considered, the X-ray tomography and the so-called "LIght Scattering". X-ray tomography allows to obtain 3D reconstructions of the internal structure of materials with spatial resolution of microns and even nanometers, which has allowed for the first time to study structural parameters of the foams considered and their influence on physical properties. On the other hand, Light Scattering, widely used in the case of water-based cellular materials, allows to determine in a very simple way two crucial parameters of the structure of cellular materials, cell size and cellular anisotropy. This research has managed to adapt the existing results in aqueous foams in order to effectively apply Light Scattering in the case of solid polymeric foams. Finally, once both techniques have been successfully applied to the study of conventional cellular materials, they have been applied in non-conventional cellular materials, which has allowed us to visualize for the first time their structure in 3D and obtain the first evidence on the possibility of manufacturing transparent polymeric cellular materials, as long as the cell size is small enough.

Subject Areas: Biology and Bio-materials

Instruments: I13-1-Coherence