Effect of Organic Co-blowing Agents on the Morphology of CO2 Blown Microcellular Polystyrene Foams.

0476682 - ÚCHP 2018 RIV NL eng J - Journal Article
Nistor, A. - Topiař, Martin - Sovová, Helena - Kosek, J.
Effect of Organic Co-blowing Agents on the Morphology of CO2 Blown Microcellular Polystyrene Foams.
Journal of Supercritical Fluids. Roč. 130, DEC 2017 (2017), s. 30-39. ISSN 0896-8446. E-ISSN 1872-8162
R&D Projects: GA ČR(CZ) GA14-18938S
Institutional support: RVO:67985858
Keywords : polystyrene * closed-cell microcellular foam * co-blowing agent
OECD category: Chemical process engineering
Impact factor: 3.122, year: 2017

Microcellular polystyrene (PS) foams blown with supercritical CO2 in batch processes have usually porosities lower than desired for good heat insulators. Porosities can be increased by co-blowing agents. We studied effects of n-pentane (nC5) and cyclopentane (cC5) on foaming in a batch. Neat PS films were impregnated first with nC5 or cC5, then with high-pressure or supercritical CO2, and finally foamed. Cell diameters and bulk porosities were determined from SEM images. The co-blowing agents reduced the solid skin, they acted mainly as plasticizers, both porosity and cell diameters increased with their concentration. After crossing a particular concentration, the cell size remained almost constant. Impregnation of neat PS with high-pressure liquid CO2 near room temperature enabled to prepare foams with cell diameters below 10 μm and porosities about 80 %, which has not been reported before. Hence, organic co-blowing agents could be used to increase the porosity of CO2 blown foams.
Permanent Link: http://hdl.handle.net/11104/0273591