Polymer electrostatics: detection and speciation of trapped electric charges by electric probe and analytical electron microscopy

Abstract

This work reviews new probe and electron microscopy approaches for the detection of charged domains in insulating polymers, as well as for the identification of the charge‐bearing species: scanning electric potential microscopy (SEPM), electric force microscopy (EFM) and energy‐loss spectroscopy imaging in the transmission electron microscope (ESI‐TEM). The SEPM and EFM micrographs show patterned domains bearing excess electric charges and extending for tens of nanometers, in polymer latex particles and films. The charged species are identified by ESI‐TEM as emulsion polymerization initiator and surfactant residues, as well as the associated counter‐ions. Charged domains are also observed in common thermoplastic polymers, producing unexpectedly large electric potential gradients.

Multifunctional Nanocomposites between Different Carbon Nanostructures and Styrene Acrylic Latex

“…The KFM images of all samples reveal non-uniform charge distribution along the analyzed surfaces. Analogously to the well-known natural rubber latex, the SA latex is not an homogeneous material, with a pronounced amount of negative charges inside of the particles, 20 as can be seen on Figure 1. There is also evidence for positive charge in the edges of rGO but more so over the mica substrate.…”