Multi-scale tomographic analysis of polymeric foams: A detailed study of the cellular structure

• Published in: European polymer journal 2018-12, Vol.109, p.169-178
• Main Authors: Pérez-Tamarit, S., Solórzano, E., Hilger, A., Manke, I., Rodríguez-Pérez, M.A.
• Format: Article
• Language: English
• Subjects: Anisotropy; Cellular structure; Comparative studies; Crosslinking; Foaming; Image analysis; Imaging; Low density polyethylenes; Multiscale analysis; Plastic foam; Polyethylene; Polymeric foams characterization; Polymers; Polyurethane; Polyurethane foam; Size distribution; Solid phases; Structural analysis; Struts; Synchrotron radiation; X ray microtomography; X-ray tomography
• ISSN: 0014-3057; 1873-1945
• DOI: 10.1016/j.eurpolymj.2018.09.047

[Display omitted] •A multi-scale tomographic approach was used to study the structure of polymeric foams.•Gaseous phase features were examined using conventional lab-scale X-ray tomography.•Solid phase parameters were analysed by means of synchrotron X-ray tomography.•A novel analysis method to separate the solid phase in struts and walls was developed. This manuscript presents a detailed characterization of the cellular structure of two types of polymeric foams by non-destructive multi-scale X-ray computed micro-tomography. This comparative study is conducted in two different polymeric materials –rigid polyurethane foams and cross-linked low density polyethylene foams-. Based on this technique and using 3D image analysis, conventional descriptors of the foams gaseous phase (cell size distribution, mean cell size and anisotropy ratio) are characterized at a standard voxel size of 5 µm. Complementarily, 0.4 µm voxel size synchrotron X-ray tomography data sets have been used to characterize, using a new image analysis approach, features of the solid phase of the foams (fraction of mass in the struts and thickness of the different entities of the solid architecture: struts and walls). The presented methodology, based on multi-scale tomographic analysis, allows obtaining a better understanding of the connection between foaming process and cellular structure and is important to gain knowledge on the structure-properties relationships for these materials.