Highly permeable macroporous polymers synthesized from pickering medium and high internal phase emulsion templates.

Effect of additives on the pore structure of polymer foams obtained from Pickering HIPE templates Various routes were investigated to create pore throats in closed-celled poly-Pickering-HIPEs; we tried to dissolve the silica particles used as emulsifiers out of the thin films separating individual pores by adding NaOH into the aqueous phase, which resulted indeed in the formation of interconnects of the size of the silica particles (from about 5-10 μm). We also explored the incorporation of 1 wt.-% degradable CaCO3 particles, 25 μm in size, into the polymer (walls) followed by their degradation using HCl but the particles were too well dispersed to form interconnects (leaving just a rough pore surface after etching). Furthermore, we investigated the addition of additives such as methanol and polypropylene oxide to the emulsion template, however interestingly enough the emulsion templates remained stable but no pore throats were observed in the poly-Pickering-HIPEs afterwards.