%0 Journal Article %1 HAMANN2021102087 %A Hamann, Martin %A Quell, Aggeliki %A Koch, Lukas %A Stubenrauch, Cosima %D 2021 %J Materials Today Communications %K koch stubenrauch %P 102087 %R https://doi.org/10.1016/j.mtcomm.2021.102087 %T On how the Morphology Affects Water Release of Porous Polystyrene %U https://www.sciencedirect.com/science/article/pii/S2352492821000799 %V 26 %X Polymerizing a water-in-styrene high internal phase emulsion (HIPE) and subsequently expanding the polyHIPE through heating could present an environmentally friendly alternative to the synthesis of industrially expanded polystyrene foams where pentane is used as blowing agent. The polyHIPE has to have a closed-pore morphology to build up enough pressure during heating so that the polystyrene matrix expands before the water escapes. We found that the polyHIPE has to contain only small amounts of the crosslinker DVB to keep the Tg of the polystyrene matrix low and thus to ensure better expandability. In addition, the water volume fraction Φdisp should be as high as possible to obtain polymer foams with low densities. To find a HIPE with a suitable composition for expansion, we systematically varied Φdisp, the DVB concentration cDVB, and the surfactant concentration csurf. We investigated each composition by studying the stability of the HIPE before polymerization, by analyzing the morphology of the polyHIPEs with scanning electron microscopy, and by examining the water release rates of the polyHIPEs. To have a highly porous polystyrene foam, Φdisp must be ≥ 74 vol%. However, no suitable composition was found with this high Φdisp which is why we suggest that a stepwise, systematic reduction of Φdisp at the expense of the porosity could be a solution to this dilemma.

@article{HAMANN2021102087, abstract = {Polymerizing a water-in-styrene high internal phase emulsion (HIPE) and subsequently expanding the polyHIPE through heating could present an environmentally friendly alternative to the synthesis of industrially expanded polystyrene foams where pentane is used as blowing agent. The polyHIPE has to have a closed-pore morphology to build up enough pressure during heating so that the polystyrene matrix expands before the water escapes. We found that the polyHIPE has to contain only small amounts of the crosslinker DVB to keep the Tg of the polystyrene matrix low and thus to ensure better expandability. In addition, the water volume fraction Φdisp should be as high as possible to obtain polymer foams with low densities. To find a HIPE with a suitable composition for expansion, we systematically varied Φdisp, the DVB concentration cDVB, and the surfactant concentration csurf. We investigated each composition by studying the stability of the HIPE before polymerization, by analyzing the morphology of the polyHIPEs with scanning electron microscopy, and by examining the water release rates of the polyHIPEs. To have a highly porous polystyrene foam, Φdisp must be ≥ 74 vol%. However, no suitable composition was found with this high Φdisp which is why we suggest that a stepwise, systematic reduction of Φdisp at the expense of the porosity could be a solution to this dilemma.}, added-at = {2021-02-12T11:15:31.000+0100}, author = {Hamann, Martin and Quell, Aggeliki and Koch, Lukas and Stubenrauch, Cosima}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/281e24a7497c877abe387c389fad06d26/nataliepreisig}, description = {On how the Morphology Affects Water Release of Porous Polystyrene - ScienceDirect}, doi = {https://doi.org/10.1016/j.mtcomm.2021.102087}, interhash = {92832a8d0fa9654ab8353af3da1c2581}, intrahash = {81e24a7497c877abe387c389fad06d26}, issn = {2352-4928}, journal = {Materials Today Communications}, keywords = {koch stubenrauch}, month = {3}, pages = 102087, timestamp = {2021-12-10T10:54:35.000+0100}, title = {On how the Morphology Affects Water Release of Porous Polystyrene}, url = {https://www.sciencedirect.com/science/article/pii/S2352492821000799}, volume = 26, year = 2021 }