Synthesis of Polymeric Nanogel via Irradiation of Inverse Micelles Technique

Covalently cross-linked nanogels were prepared via irradiation of inverse micelles that had been prepared from radiation crosslinkable polymer, water, oil and surfactant. A mixture of polymer, water, heptane and sodium dioctyl sulfosuccinate (AOT) at certain compositions forms inverse micelles with the size ranging from 2 to 8 nm. The hydrophilic head of the surfactant facilitates encapsulation of water soluble polymer. If the entrapped polymer is radiation crosslinkable, it is expected that upon irradiation, polymerization shall take place in such small and confined space, leading to formation of nano-sized polymeric gel. Meanwhile, emulsion at 2 nm size was chosen for gamma irradiation process. The formation of the nano-sized discreet gel using irradiation of inverse micelles technique was proven at a dose as low as 5 kGy to obtain nanogel sized ~ 95 nm.