Synthesis of Hybrid Nanocapsules by Miniemulsion (Co)polymerization of Styrene and γ-Methacryloxypropyltrimethoxysilane

Abstract

Hybrid nonacapsules are synthesized by miniemulsion (co)polymerization of styrene and 3-trimethoxysilylpropylmethacrylate silane (MPS) in one step. Hydrocarbon droplets are encapsulated by organic−inorganic hybrid material, which is formed by simultaneous free radical polymerization reaction and hydrolysis−condensation reaction of organosilane in MPS. The morphology and the microstructure are characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), solid-state NMR, and infrared (IR) spectroscopy. The capsule morphology is achieved by polymerization inducing phase separation within minidroplets dispersed in aqueous phase. The feasibility of the final morphology is analyzed by thermodynamic and kinetic factors first. Particle nucleation processes with different formulation are followed by DLS, and it has a great influence on the latex morphology. Monomer/hydrocarbon ratio in the droplets and MPS fraction in the capsules are also of great important to the morphology due to their influence on phase separation behavior and mechanic properties of capsules, respectively. Finally, the loading and releasing processes of this capsule are monitored by ultraviolet−visible (UV) measurement.