The effect of pressurized and fast stabilization on one step batch foaming process for the investigation of cell structure formation

• Published in: The Journal of supercritical fluids 2016-06, Vol.112, p.143-152
• Main Authors: Shirvan, M. Mokhtari Motameni, Famili, M.H.N., Alkuh, M. Soltani, Golbang, A.
• Format: Article
• Language: English
• Subjects: Cell forming mechanism; Depressurization; Foaming; Foams; Formations; Forming; Morphology; Nucleation; Pressure drop; Saturation; Stabilization; Supercritical fluids
• ISSN: 0896-8446; 1872-8162
• DOI: 10.1016/j.supflu.2015.11.023

•A fast and pressurized stabilization section was designed and built.•The stabilization section was added to the one step batch foaming.•Stabilization was performed during and after the application of pressure drop.•The effect of stabilization process on cell structure was temperature dependent.•A new mechanism of cell formation in microcellular foams was proposed. Control of cell structure during pressure drop is essential for the investigation of cell formation mechanism. In this work, a one step batch foaming setup was totally redesigned to stabilize foam structure at initial stages of cell forming during and after depressurization as a novel idea. The saturation pressure, duration of pressure drop and foaming temperatures were 18.5MPa, 100ms and 70, 90, 110°C, respectively. The shortest stabilized foaming time was 5ms and the longest was 5000ms. For comparison purposes non-stabilized samples were also produced. It was concluded that the effect of stabilization on foam morphology is dependent on the foaming temperature. Foam structure at foaming temperatures of 70°C did not change with change of foaming time significantly. Foam structure at foaming temperatures of 110°C for the shortest and the longest foaming times changed from 90μm to 170μm and 7E+06cell/cm3 to 8E+06cell/cm3.