| abstract |
High internal phase emulsions (HIPEs) and polyHIPEs formed therefrom are described. HIPE components have been adjusted to delay and/or prevent polymerization and free radical decomposition at certain temperatures. Methods include preparing two water-in-oil emulsions; one emulsion includes an oxidizing initiator at a concentration not sufficient to induce polymerization, and another emulsion includes a reducing agent. The two emulsions may be stored for months. When combined, a redox reaction is induced, resulting in polymerization (polyHIPE formation) at temperatures below 100°C, such as between 20° C and 40° C. This allows a final composition to be formed in situ, with or without highly sensitive materials, including biologically-derived or active constituents (e.g., cells, growth factors, enzymes, proteins, drugs, chemoactive agents). The polymerization rate may be short, as fast as thirty seconds. HIPE components as well as the redox reaction may be controlled to manipulate time to cure, pore size, distribution of pores, and/or internal contents. |