Two-step micro cellular foaming of amorphous polymers in supercritical CO2
DUMON, Michel
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 1 LCPO : Polymerization Catalyses & Engineering
< Réduire
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 1 LCPO : Polymerization Catalyses & Engineering
Langue
en
Article de revue
Ce document a été publié dans
Journal of Supercritical Fluids. 2011, vol. 57, n° 1, p. 87-94
Elsevier
Résumé en anglais
Microcellular foaming of amorphous rigid polymers, polymethylmethacrylate (PMMA) and polystyrene (PS) was studied in supercritical CO2 (ScCO2) in the presence of several types of additives, such as triblock ( styrene-co- ...Lire la suite >
Microcellular foaming of amorphous rigid polymers, polymethylmethacrylate (PMMA) and polystyrene (PS) was studied in supercritical CO2 (ScCO2) in the presence of several types of additives, such as triblock ( styrene-co-butadiene-co-methylmethactylate, SBM and methylmethacrylate-co-butylacrylate-co-methylmethacrylate, MAM) terpolymers. This work is focused in the two-step foaming process, in which the sample is previously saturated under ScCO2 being expanded in a second step out of the CO2 vessel (e.g. in a hot oil bath) where foaming is initiated by the change of temperature near or above the glass transition temperature of the glass/polymer glassy system. Samples were saturated under high pressures of CO2 (300 bar), at room temperature, for 16 h, followed by a quenching at a high depressurization rate (150 bar/min). In the last step, foaming was carried out at different temperatures (from 80 degrees C to 140 degrees C) and different foaming times (from 10 s to 120s). It was found that cellular structures were controlled selecting either the additive type or the foaming conditions. Cell sizes are ranging from 0.3 mu m to 300 mu m, and densities from 0.50 g/cm(3) to 1 g/cm(3) depending on the polymers considered.< Réduire
Mots clés en anglais
Nanostructured
Supercritical carbon dioxide
Microcellular foaming
Amorphous polymers
Additives
Origine
Importé de halUnités de recherche