(2e) Production of Spherical Polyamide Particles for Additive Manufacturing By Precipitation
In this contribution, we shed light on the formation process of spherical micron-sized polyamide particles via precipitation. Short-chained alcohols for polyamides are used in pressure resistant autoclaves at high temperatures to dissolve the polyamide and subsequently to precipitate spherical particles upon decreasing the temperature. This way, direct transformation of granular bulk material into spherical particles with narrow size distribution can be achieved. The precipitation products are thoroughly characterized regarding morphology and size, structural and thermal properties. Therefore analysis via electron microscopy, static laser scattering, X-ray diffraction and dynamic scanning calorimetry is conducted. Furthermore, the flowability of the powders is investigated and product properties are correlated to process parameters, especially to temperature-time dependencies.
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