Polystyrene/magnetite hybrid foams prepared via ⁶⁰Co γ-ray radiation of high internal phase emulsions

In this study, polystyrene (PS) solid foam with cell size of about 1 um and low polydispersity is prepared via γ-ray radiation induced high internal phase emulsions (HIPEs) at room temperature. The density of the foams can be as low as 0.05 g/cm³. The kinetics and molecule weight of styrene (S) polymerizing in continuous phase of HIPEs is studied. It is found that the molecule weight is greatly lower than the PS obtained from the polymerization in dispersed phase of emulsion. In addition, the authors study the mechanical properties of solid foam. The compression resistance of solid foam obtained from radiation method is better than these obtained from conventional method. At the same time, magnetite is added into the dispersed phase when prepared the HIPEs to fabricate magnetite hybrid PS foam. The saturation magnetization (Ms), remanent magnetization (Mr), and coercivity (Hc) of the hybrid foam are 25 emu/g, 15 emu/g, and 350 Oe, respectively. The results revealed that the hybrid foams have some superparamagnetic.