A Surfactant Directed Microcrystalline Cellulose/Polyaniline Composite with Enhanced Electrochemical Properties.

Mahnaz Abdi,Rawaida Liyana,Ramin Javahershenas,Paridah Md Tahir

doi:10.3390/molecules23102470

Abstract

In this study a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was used as a soft template for in situ chemical polymerization of aniline on the surface of microcrystalline cellulose (MCC). The morphology of the wire-like and porous nanostructure of the resulting composite was highly dependent on the MCC and CTAB concentrations. The effect of the MCC and CTAB concentrations on the electrochemical and morphological properties of the polyaniline (PAni) nanocomposite was studied. Cyclic voltammograms of modified PAni/MCC/CTAB electrode displayed a high current response and the effect of scan rate on the current response confirmed a diffusion controlled process on the surface of the electrode that makes it suitable for sensor applications. The overlapping characteristic peaks of pure PAni and MCC caused peak broadening at 3263 cm−1 in the IR spectra of PAni/MCC/CTAB nanocomposite that revealed the interaction between NH of PAni and OH group of MCC via electrostatic interactions. The addition of MCC to PAni through chemical polymerization decreased the thermal stability of composite compared to pure PAni. Lower crystallinity was observed in the XRD diffractogram, with 2 theta values of 22.8, 16.5, and 34.6 for PAni/MCC, confirming the formation of PAni on the MCC surface.

Highlights

Natural cellulose fibers contain crystalline and amorphous domains
As the potential increased the conversion of the emeraldine form to the fully oxidized pernigraniline form occurred at 0.81 V, which is in agreement with the results reported by others [20]
In this work it has been shown that the physical and electrochemical properties of polyaniline were enhanced in the presence of Microcrystalline ellulose (MCC) and the cationic surfactant cetyltrimethylammonium bromide (CTAB)

Summary

Introduction

Natural cellulose fibers contain crystalline and amorphous domains. Microcrystalline ellulose (MCC) can be synthesized by different processes such as reactive extrusion, enzyme mediated, and acid hydrolysis in that way the amorphous regions are removed and the crystalline domains remain. The hydroxyl groups covering the cellulose surface and orderly arrangement of molecules in MCC allows the cellulose to react well with a variety of materials, including conducting polymers [1]. Conducting polymers are some of the most studied materials that have been used to modify the crystals and fibers of cellulose. The poor solubility and dispersibility of conducting polymers in common organic solvents are limiting factors for them to be used in different applications [5,6]. On the other hand the electron transfer in a bulky polymer is relatively slow which limits its application in Molecules 2018, 23, 2470; doi:10.3390/molecules23102470 www.mdpi.com/journal/molecules

Methods

Results

Conclusion