From Aqueous Dispersions to Functional Materials: Capillarity and Electrostatic Adhesion

Abstract The author was first acquainted with polymer lattices as model particles for studying sedimentation phenomena, evolving towards the elucidation of synthetic and natural latex heterogeneity and microchemistry. This brought new elements to understand the remarkable mechanical properties of natural rubber, leading to the latex route for making nanocomposites. These materials show exceptional properties that are largely due to electrostatic adhesion, a concept that had been previously presented by Deryagin but was later abandoned. Electrostatic adhesion is the outcome of ion partition and self‐assembly within drying aqueous dispersions, producing co‐existing domains with opposite charges. Their examination allowed several experimental observations leading to the proposal of mechanisms to explain hitherto challenging electrostatic phenomena shown by solids and liquids. Water plays a decisive role in all the different phenomena described in this account. Drying aqueous dispersions of colloidal polymers, other particles and low‐MW solutes is an effective way to overcome compatibility limitations while making multi‐phase structural or functional materials. The remarkable properties of the solids thus obtained are largely due to electrostatic adhesion between patterned charge domains revealed by scanning electric probes and analytical electron microscopy.
Source: Contrast Media and Molecular Imaging - Category: Radiology Authors: Tags: Personal Account Source Type: research