Synthesis of Mesoporous Polymer Networks using Thermokinetic Processing of a Colloidal Template

Solubility-induced phase separation techniques have arisen as popular methods for preparing porous polymeric materials, yet controlling the resulting pore size and tortuosity is difficult as it depends on heat and mass transport into the pre-cursor polymer solution. To help address the shortfalls of these and other conventional techniques, we introduce a new phase separation technique involving thermal processing of colloidal templates based on self-assembling nanoemulsions to create polymer networks with bicontinuous pore morphologies. Controlling a combination of temperature- and kinetically-dependent nanodroplet assembly with photocuring of polymer networks in one of the liquid phases produces bicontinuous structures across a range of length scales, which can be rendered porous through gentle solvent exchange to eliminate the colloidal template. We demonstrate control over the morphology and length scales of the droplet template structure by changing the temperature history and processing time during colloidal assembly and phase separation before photo-induced arrest. This control of processed structure is successfully translated to porous polymer networks, providing a new route to porous structures that is orthogonal to polymer chemistry.