Introductory Remarks from AIChE President, Christine Grant
AIChE Annual Meeting
Sunday, November 13, 2022 - 3:00pm to 3:05pm
Foaming experiments were conducted isothermally in a free-foaming mode in a special foaming cell. Polymer samples (1mm-thick, 10 mm x 30 mm) were loaded in the foaming cell on a Teflon tray that minimizes direct contact of the sample with the cell body. Cell temperature was measured and controlled with an RTD 100. After closure of the cell, the cell was first purged with carbon dioxide, and then filled with carbon dioxide to a target pressure. In this study all foaming experiments were conducted after saturation in carbon dioxide at 200 bar for 1 h at a set of foaming temperatures followed by rapid depressurization. The saturation temperatures were selected based on the results of a parallel study in which melting and crystallization temperatures were identified for these polymers exposed to carbon dioxide. The foaming temperature ranges were from 92 to 112 oC (for EVACO-0010), from 72 to 90 oC (for EVACO-1010) and from 46 to 66 oC (for EVACO-2010).
The generated foams were characterized with respect to their foam bulk densities and pore morphologies. Bulk foam densities were determined by measuring the mass of a foam sample in air and then submerged in water to assess its volume and thus the density. Pore size determinations were carried out with a benchtop SEM unit using freeze-fractured, sputter coated samples. The SEM micrographs were further analyzed using ImageJ software to generate pore size distribution in the foams generated at different temperatures from different EVACO samples which will be presented in the poster.