Microstructure Characterization of Low Density EPS

Abstract:

This paper presents a procedure to determine the geometry of a representative unit cell for low density expandable polystyrene foams (EPS), specifically, 8.5 kg/m³, 12 kg/m³ and 23 kg/m³. Several researches used different geometries to describe a unit cell, but none indicate neither how they established the shape of it nor how they determinate its dimensions. The foam specimens preparation is described in order to be observed in a scanning electron microscope (SEM) and the average edge length and average face thickness are calculated, based on SEM images. A mathematical procedure to calculate the size that the edge geometry would present is described and is based on an analytic model available in literature. With the obtained values, a theoretical geometry adjusted to a tetrakaidecahedron was built in CAD software. Thereupon, this geometry is compared with the SEM observations, from this comparison it is concluded that said model is not applicable to these low density EPS foams. Finally, the geometry is readjusted to obtain a representative unit cell able to be used in future research.

• Periodical: Applied Mechanics and Materials (Volume 420)
• Pages: 167-176
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.420.167
• Online since: September 2013
• Authors: Diosdado De La Pena Jose Angel, Plascencia Mora Hector, Torres Cisneros Miguel, Mondragon Sanchez Maria de Lourdes
• Keywords: EPS, Microstructure Edge Geometry, Unit Cell

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