Synthesis of hybrid nanocomposites based on new triazeno copolymers and montmorillonite used for detecting metal ions

Abstract

The modern synthesis of novel functional materials with improved properties includes that of hybrid nanocomposites composed of inorganic nanoparticles and organic derivatives, where controlling the molecular structure at atomic and macroscopic dimensions is a key factor, with a major effect on performance. An extension of this approach to the field of nanocomposites containing photopolymers with triazene groups attached on a methacrylic backbone could be of great interest in the future development of chemosensors and photoresists, among others. Photopolymer/clay nanocomposites were prepared by in situ free radical copolymerization of 1‐(phenyl)‐3‐(2‐methacryloyloxyethylcarbamoyloxyethyl)‐3‐methyltriazene‐1 or 1‐(p‐methoxyphenyl)‐3‐(2‐methacryloyloxyethylcarbamoyloxyethyl)‐3‐methyltriazene‐1 and vinyl acetate or styrene in solution and in the presence of 3 and 5 wt% of organically modified montmorillonite. The characterization of the nanocomposites and pure copolymers was achieved through 1H NMR and Fourier transform infrared spectroscopy, gel permeation chromatography, thermogravimetric analysis, X‐ray diffraction, atomic force microscopy and fluorescence analysis. The morphologies and properties of the nanocomposites are dependent on the nature of the triazene, on the co‐monomer structure and on the organoclay content. Also, the fluorescence response of these nanocomposites towards certain metal ions (Fe3+, Cu2+, Hg2+, Ni2+) in dimethylformamide solution was investigated. The effect of uranyl ions on the fluorescence intensity of the nanocomposites in solution or as films could be exploited in the development of ‘turn‐off’ or ‘turn‐on’ chemosensors for this type of analyte. Triazeno copolymer/organophilic montmorillonite nanocomposites with exfoliated (not completely exfoliated) or exfoliated and intercalated structures exhibit distinct characteristics concerning their fluorescence behaviour, a higher sensing ability towards certain target compounds (Fe3+, UO22+) being evidenced for those incorporating 3 wt% organoclay in solution and as films. Copyright © 2010 Society of Chemical Industry

Critical assessment of structural changes in some copolyamide‐clay hybrid materials in correlation with the filler characteristics

“…[ 60 ] The attenuated intensity of the peak is a clear indication of the incomplete exfoliation of clay nanosheets. [ 61 ]…”

Preparation of amphiphilic block copolymer containing triazene moieties and fluorescence study

“…In the literature, there are only few reports in relation to the quality of the triazene derivatives to act as fluorophores and especially, as chemosensors in the detection of ionic metals. 12,13,46 As a continuation of our work concerning the photochemical performance of some triazene polymers in the development of sensors for metal cations, we investigated some photophysical aspects of the triazene containing block copolymer in DMF solutions and in thin films. When excited at 320 nm, the PAA-b-(PDA-co-PUMA-T) solution emits a blue fluorescence with well-defined maximum positioned around 400 nm, whereas the maximum of the diblock copolymer in thin film is blue shifted with 25 nm (λ em = 375 nm).…”

“…[8][9][10][11] Moreover, in recent publications, the important attribute of the triazene copolymers to emit a strong fluorescence with a maximum around 400 nm was confirmed, feature of interest in chemosensor applications for the detection of some metal ions. 12,13 Meanwhile, the modern developments in reversible addition-fragmentation chain transfer (RAFT) polymerization have proved that this is one of the most versatile methods of controlled radical polymerization, successfully employed in preparing complex macromolecular architectures such as linear block copolymers, star and brush polymers, dendrimers. [14][15][16] Usually, RAFT polymerization is a living polymerization that yields polymers with a low polydispersity index and a predetermined molecular weight 16 and facilitates the controlled polymerization of a wide range of nonfunctional monomers under a great variability of experimental conditions.…”

Synthesis, characterization, and application of a triazene‐based polysulfone as a dye adsorbent

“…Recently, triazenes have been received much attention due to their novel physical and chemical properties, and prospects of their application in the synthesis of photosensitive polymers,1–5 13 N‐labeled azo compounds,6 conductive polymer,7 and hybrid nanocomposites are used for detecting metal ions 8. Moreover, they have been applied as coordination agents in inorganic chemistry,9, 10 triazene linkers,11–15 photolabile linker in solid‐phase chemistry,16 solid‐phase extraction,17 thiophenol synthesis,18 and improvement in semiconductor laser printing 19.…”