Synthesis and Characterization of rGO-coated PMMA Beads Based TPU Nanocomposites for Gas Sensing Application

Abstract

Nanocomposites of polymers have recently gotten a lot of interest in the materials world since they often have more advanced properties than their counterpart polymer micro-composites. A novel reduced graphene oxide (rGO)coated poly (methyl methacrylate) (PMMA) beads based thermoplastic polyurethane (TPU) nanocomposites were prepared by the melt mixing method. Graphene oxide was synthesized by following improved hummer’s method and reduce it thermally at 300 oC. The PMMA beads were coated with reduced graphene oxide by the solution mixing method and then this synthesized rGO coated PMMA beads were introduced in TPU matrix in 1, 2, 5, and 8 % wt. of TPU along with 1% carbon nanotubes (CNTs) by following melt mixing method in an internal mixer. Scanning electron microscopy (SEM) was performed to examine the dispersion of fillers in the nanocomposites. Fourier transform infrared spectroscopy (FTIR) was applied for functional groups analysis. X-ray diffraction analysis results were obtained to know about the crystal structure of the GO, rGO and rGO coated PMMA beads. Raman spectrum was obtained to know the defects after oxidation and reduction of graphite and GO, respectively. The effect of rGO coated PMMA and CNTs was observed on the conductivity properties of the synthesized polymer nanocomposites. Electrical conductivity values were obtained using four probe for these nanocomposites and the data showed that the synthesized polymer nanocomposites were conductive. Gas sensing application of these composites could be possible.