The Dispersion and Coagulation of Negatively Charged Ca2Nb3O10 Perovskite Nanosheets in Sodium Alginate Dispersion

Abstract

Chemically exfoliated nanosheets have been extensively employed as functional nanofillers for the fabrication of polymer nanocomposites due to their remarkable electrical, magnetic and optical properties. However, achieving a good dispersion of charged nanosheets in polymer matrix, which will determine the performance of polymer nanocomposites, remains a challenge. Herein, we investigated the dispersion and aggregation behavior of negatively charged Ca2Nb3O10 (CNO) perovskite nanosheets in negatively charged sodium alginate (SA) aqueous dispersion using dynamic light scattering (DLS). When CNO nanosheets meet with SA, aggregation and coagulation inevitably occurred owing to the absorption of SA on nanosheets. By controlling the electrostatic attraction between positively charged poly(ethylene imine) (PEI) and negatively charged SA, the charge density and hydrodynamic size of SA can be tuned to enable the good dispersion of CNO nanosheets in SA. This result may provide a new strategy to achieve the good dispersion of charged nanosheets in charged polymers for the rational design of multifunctional nanocomposites.

From Ionic Nanoparticle Organic Hybrids to Ionic Nanocomposites: Structure, Dynamics, and Properties: A Review

“…The fluidity could be tuned by altering the graft density of the shell to the core and the shell–core, interaction which can be tuned by core preheating or by changing the surface functional moieties of the core by acid or alkaline etching [ 115 ]. In other types of materials, by controlling the electrostatic attraction between positively charged poly(ethylene imine) (PEI) and negatively charged sodium alginate (SA) dispersion, the charge density of SA can be tuned to enable the good dispersion of Ca Nb O perovskite nanosheets in SA [ 116 ]. MXene is modified using an organosilane (OS) with acidic moieties, then an alkaline oligomer is electrostatically grafted to form the resultant stable electron-balanced MXene nanoparticle organic hybrids.…”