A polyHIPE-templated composition-of-matter afforded by interfacial polymerization, comprising a polymer of alternating residues of hydrophobic and hydrophilic monomers. The described composition-of-matter is characterized by an open-, quasi-closed- or a truly closed-cell microstructure, whereas the latter is capable of non-releasably or releasably encapsulating an organic or aqueous composition therein for extended periods of time, as well as various uses thereof.