Raman spectroscopy of conducting poly (methyl methacrylate)/polyaniline dodecylbenzenesulfonate blends

Abstract

Polyaniline soluble in organic solvents was prepared using dodecylbenzenesulphonic acid (DBSA) as functional dopant. The solubility parameter was calculated and the most suitable solvent chloroform was checked for the solubility and the most compatible polymer PMMA was selected for blending. Miscibility was maximized with 1% by weight of hydroquinone. Blending of doped polyaniline with dodecylbenzenesulphonic acid (PAni.DBSA) in poly (methyl methacrylate) (PMMA) was explained by a change in the conformation of the polymeric chains leading to an increase in the conductivity. The electrical conductivity increased as the weight percent of PAni.DBSA increased, showing a percolation threshold as low as 3.0% by weight and the highest conductivity was achieved at 20% by wt of PAni.DBSA. Scanning electron micrographs showed lowest level of phase separation. Raman spectroscopy is used to characterize the blending process of two polymers aiming to understand the transformations in different types of charged segments. Raman results give complementary data about the blending process showing that together with the structural change of the polymeric chains, there is also a chemical transformation of these polymers. Analysis of Raman spectra was done investigating the relative intensities of the bands at 574 cm −1 and 607 cm −1 . A relationship between conductivity and Raman was also proposed.

Structural and Morphological Characteristics of Polyaniline Synthesized in Pilot Scale

“…PAni-B spectra presented characteristic bands at 1170 (C-H bending); 1206 (C-N stretching); 1502 (C=N stretching); 1560 (N-H bending) and 1598 cm −1 (C=C stretching) (Mažeikienė et al 2007;Cirić-Marjanović et al 2008;Moravková et al 2012). PAni-DBSA spectra, in turn, presented characteristic bands at 1190 (C-H bending); 1,260 (C-N stretching); 1,343 (C-N + stretching); 1,530 (C-C stretching); and 1620 cm −1 (C-H stretching) (Nobrega et al 2012;Ibrahim 2013;Shakoor and Rizvi 2010). The conductive nature of PAni-DBSA can be associated to the band located at 890 cm −1 (arrow in Fig.…”

Recent advances in linear and nonlinear Raman spectroscopy. Part V

“…They found that Raman intensities computed for chains of different lengths allow one to conclude that cumulenic molecules could be detected and identified. Solutions of polyaniline in organic solvents were prepared by Shakoor and Rizvi using dodecylbenzenesulfonic acid as a functional dopant . They then used Raman spectroscopy to characterize the blending process of two polymers with the aim of understanding the transformations in different types of charged segments.…”

A density functional theory study of Raman modes of cadmium hexathiohypodiphosphate (CdPS3)

“…Single crystals CdPS 3 were prepared by direct method by heating a mixture of stoichiometric amounts of elemental Cd, P and S powders in an evacuated quartz tube at 800 to 900°C for 10 days [26,27]. The resulting material contained mostly small crystals, but also included a few large, thin single crystals about 1 cm 2 in area and 5 to 20 mm in thickness.…”

“…Insertion of intrinsic conducting polymer in layered host materials results in a dramatic modification of the physical properties, which has led to various applications as nonlinear optical materials [14,15], magnetic materials [16,17], catalysts and cathode materials in battery applications [18,19]. Different synthetic approaches [20,21] combining a variety of host [22] and guest molecules [23][24][25] [26][27][28] and the literature on its counterpart using density functional theory based calculations is still lacking.…”