Method for preparing porous polyurethane materials with controlled pore size and shape using isocyanates, polyols, and additives, and the porous polyurethane materials prepared therefrom. Method for preparing porous polyimides using at least one polyamine and a dianhydride and the porous polyimides materials prepared therefrom. The porous materials are useful for energy management, such as thermal, impact and vibration energy, and can exhibit improved fire-resistant performance.