A Latex‐Based Route to Disperse Carbon Nanotubes in Poly(2,6‐Dimethyl‐1,4‐Phenylene Ether)/Polystyrene Blends

Abstract

Electrically conductive composites consisting of carbon nanotubes (CNTs) in a poly(2,6-dimethyl-1,4-phenylene ether)/polystyrene (PPE/PS) blend are prepared by latex technology. The latter consists of 4 steps: preparation of an aqueous dispersion of CNTs, mixing with a polymer latex, solvent removal by freeze-drying and processing. In the first route, PPE/PS blend latexes are directly used to prepare nanocomposites by latex technology. The CNT/PPE/PS composites display an increased glass transition temperature compared to unfilled material and a percolation threshold as low as 0.3 wt% of CNTs. Secondly, CNT/PS masterbatches prepared by latex technology are mixed with PS/PPE blend pellets by extrusion. This approach constitutes a potential first step towards an industrially viable process.

Bimodal Latex Effect on Spin-Coated Thin Conductive Polymer–Single-Walled Carbon Nanotube Layers

“…CNTs can be incorporated into insulating polymers to make conductive composites by a variety of preparation techniques, including ball-milling, melt-mixing, slot-die-coating, and spin-coating, but most of them suffer from limitations in film homogeneity and thickness control. − Meanwhile, some researchers have tried to use solvent-based latex particle dispersions as a starting point for producing thin films and achieving an improved assembly of carbon nanotubes in a conductive network and lower percolation threshold. , In this so-called latex technology, small latex particles are mixed with ultrasonicated CNTs in a suitable solvent, where the large size difference of the CNTs and the latex particles are thought to aid the assembly of CNTs during the production of the final solid film. , Indeed, film formation of mixtures of latex particles and carbon nanotubes often results in a more highly conductive composite film and reduced percolation threshold, which has been explained in terms of so-called depletion interactions between the CNTs due to the presence of the much smaller latex particles …”