Synthesis and Pickering emulsifier performance of Ag/poly((2-dimethylamino)ethyl methacrylate)-co-poly(hexafluorobutyl acrylate) amphiphilic random copolymer hybrid micelles

Abstract

A new type of comolymer containing nanoparticles, Ag/poly(2-(dimethylamino) ethyl methacrylate-co-hexafluorobutyl acrylate) (Ag/P(DMAEMA-co-HFBA)) amphiphilic random copolymer hybrid micelles was synthesized and used as the high-efficiency particulate emulsifiers to stabilize Pickering emulsion. Firstly, the amphilphilic random P(DMAEMA-co-HFBA) is facilely synthesized by a one-pot radical polymerization of poly(2-(dimethylamino)ethyl methacrylate)(DMAEMA) and hexafluorobutyl acrylate(HFBA). Then, this copolymer self-assembles into spherical-like polymeric micelles, and the effect of the copolymer content on the size and morphology of P(DMAEMA-co-HFBA) micelles was determined by dynamic light scattering(DLS) and transmission electron microscopy(TEM). Then, the Ag/P(DMAEMA-co-HFBA) hybrid micelles were prepared by in suit using P(DMAEMA-co-HFBA) micelles as the nanoreactors. The synthesis mechanism of the Ag/P(DMAEMA-co-HFBA) hybrid micelles was investigated by Fourier transform infrared spectroscopy(FT-IR), X-Ray Diffraction(XRD) and TEM. The hybrid micelles showed surface activity and pH sensitivity for producing Pickering oil-in-water emulsions. The emulsification performance of Ag/P(DMAEMA-co-HFBA) hybrid micelles with different surface activity demonstrated that the Pickering emulsion with long-time stability could only be stabilized by Ag/P(DMAEMA70-co-HFBA30) hybrid micelles, indicating that the surface wettability of Ag/P(DMAEMA-co-HFBA) hybrid micelles plays a crucial role in determining the type and stability of the prepared Pickering emulsions. Additionally, the effect of pH value of the aqueous solution of Ag/P(DMAEMA-co-HFBA) hybrid micelles on the Pickering emulsion were investigated. The Ag/P(DMAEMA70-co-HFBA30) had an excellent emulsification performance at pH value 1.98 and the pH-induced phase inversion derived from obtained emulsions observed at pH higher than 5.15. These results demonstrated that Pickering emulsion could be generated using self-assembled hybrid micelles as the stabilizer, and the prepared Pickering emulsion has promising potential to be applied in the medical and coating industries.