Ordered Multilayer Nanocomposites Prepared by Electrostatic Layer-by-Layer Assembly between Aluminosilicate Nanoplatelets and Substituted Ionic Polyacetylenes

Abstract

Ordered multilayer nanocomposites have been prepared by electrostatic layer-by-layer assembly between exfoliated aluminosilicate nanoplatelets and substituted ionic polyacetylenes. Aluminosilicate saponite particles were exfoliated by means of extensive shaking and sonication of their water suspension. Atomic force microscopy and transmission electron microscopy data suggest that the exfoliated platelets have the shape of ultrathin disks with an average width of 170 ± 30 nm. Conjugated ionic polyacetylene poly(N-octadodecyl-2-ethynylpyridinium bromide) (PEPy-C18) was synthesized by spontaneous polymerization of 2-ethynylpyridine quaternized with 1-bromooctadecane. Linear build-up of multilayer nanocomposites between the exfoliated saponite particles and substituted ionic polyacetylenes was monitored by UV−vis absorption spectroscopy. AFM surface topography of the resulting films indicates that the saponite platelets cover the entire surface of the underlying layers. TEM cross-sectional images of such films show that the saponite platelets are aligned parallel to the film surface to form ordered layers. Polarized UV−vis absorption spectroscopy suggests that the polyacetylene chains are oriented parallel to the surface of the saponite layers.

Spectroscopy of Nanostructured Conducting Polymers

“…Zeolite MFI (ZSM-5) [162,163] Zeolite Y [10,11,75] Zeolite LTL (L) [163] Zeolite FAU (Faujasita) [10,11] Porous Vycor Glass (PVG) [ the pores of these membranes can be performed chemically or electrochemically. By controlling the duration of polymerization, it is possible to obtain tubes or filaments of conductive polymers.…”

“…However, these first studies only produced oligomeric products inside the zeolite cavities. Nowadays, by using the layer-by-layer technique, ordered multilayer nanocomposites have been prepared by electrostatic assembly between exfoliated aluminosilicate (saponite) nanoplatelets (averaging from 170 to 30 nm) and substituted ionic polyacetylenes, poly(N-octadodecyl-2-ethynylpyridinium bromide, (PEPy-C18) [163].…”

Energy transfer between rhodamine 3B and oxazine 4 in synthetic-saponite dispersions and films

“…Such materials are of great interest because of their properties [2], and are potential candidates to be novel optical materials [3,4]. There are various methods that can be used for constructing hybrid organic/inorganic materials, based on inorganic solid hosts, for example, the Langmuir-Blodgett method for the preparation of thin films of organic molecules on an inorganic substrate (e.g., [5]), direct intercalation into an inorganic host (e.g., [2]), in situ formation of inorganic solids with organic molecules (e.g., [6]), and electrostatic layer-by-layer assembly (e.g., [7]). …”

Lamellar nanocomposites based on exfoliated nanosheets and ionic polyacetylenes

“…Organic and inorganic hybrid materials composed of conducting polymer molecules and the unilamellar nanosheet crystallites have been attracting considerable interest due to their promising properties [1][2][3]. In these materials, the polymer molecules form the oriented arrays within the galleries of nanosheet crystallites and cause the expansion of interlayer spacing thereby influencing the overall properties of the product lamellar nanocomposite.…”