Copper Sols Stabilized by Poly(ethylene glycol-600-monolaurate) and Its Complexes with Poly(acrylic acid)

Copper sols stabilized by a polymer-colloid complex are studied via dynamic light scattering and transmission electron microscopy. It is shown that the polymer-colloid complex including poly(acrylic acid) and the nonionogenic polymeric surfactant poly(ethylene glycol-600-monolaurate) is an effective protector of copper nanoparticles formed via the reduction of Cu2+ ions in an aqueous medium. The sizes of sol particles of the nanocomposite consisting of the polymer-colloid complex and copper nanoparticles depend on the method of preparation of the nanocomposite. The incorporation of the copper nanoparticles being formed (an average diameter of 5 nm) into particles of the polymer-colloid complex leads to an insignificant change in the sizes of the complex particles. The same sizes are typical for particles of the nanocomposite formed during the introduction of surfactant micelles in the copper sol formed in the solution of poly(acrylic acid). The interaction of copper nanoparticles formed in an aqueous medium with surfactant micelles entails their aggregation; as a result, these nanoparticles turn out to be incorporated into large aggregates with equivalent radii of up to 100 nm. When poly(acrylic acid) is incorporated into this sol, the sizes of its particles insignificantly change apparently because of the low rate of structural rearrangements accompanying the formation of the polymer-colloid complex.