Permeation Properties of Laser-Sintered Polyamide 12 Sheets in Comparison to an Extruded Polyamide 12 Film
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Laser sintering of polymers is widely used for the production of individual products and small-batch series. However, the qualification of laser-sintered polymeric components for new application fields, e.g. in the food and packaging industry, is still limited due to missing knowledge on physicochemical material properties. This work investigates the mass transfer of low molecular weight substances through laser-sintered polyamide 12 sheets in comparison to an extruded polyamide 12 film. Analysis of structural material properties reveals significant differences between both materials depending on the production processes. Despite their apparent porosity, laser-sintered sheets show lower permeation coefficients for water vapor and oxygen compared to extruded films. This might be related to the higher crystallinity of the laser-sintered vs. the extruded material, arising from the slow cooling rate of the polymer in the laser sintering process.
This research brings knowledge of the different permeation behavior of laser-sintered and extruded polyamide 12 in relation to the structural properties.
KeywordsLaser sintering Permeation properties Porosity Crystallinity Crystal structure Polyamide 12
The authors would like to thank Monika Gessler from EOS Electro Optical Systems GmbH (Krailling, Germany) for her helpful advice and for providing the LS samples for this research.
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