Cationic polymer nanocapsules with oil cores as versatile water-dispersible photoreactors

The derivatization of poly(allylamine hydrochloride) with glycidyltrimethylammonium chloride and alkyl epoxides was used to obtain a library of amphiphilic polycations with variable charge density, as well as chain lengths (C8, C12) and content of the hydrophobic alkyl side groups. These polymers were investigated in detail to clarify their ability to stabilize oil-filled core–shell nanocapsules that are obtained in a facile ultrasound-assisted emulsification. The multimodal spectroscopic and microscopic characterization of the assemblies established typical values of shell thickness of ∼ 4 nm and hydrodynamic diameters of the capsules of ∼ 150 to ∼ 350 nm depending on both the shell and core materials composition. The aqueous dispersions of the capsules based on the polymers containing C12 chains (DS = 5–16 mol%) were found to be stable up to at least 1 year while the capsules based on the polymers containing shorter side groups (C8) were typically less stable for the applied liquid cores (olive oil, hexadecane, octadecene). The ability to encapsulate hydrophobic molecules and efficiently run reactions inside the nanocapsules was demonstrated for a model photooxdation reaction of perylene indicating the potential of these systems to be employed as water-dispersible photoreactors.