Highly Stable APTES Incorporated CNTs Based Ternary Polymer Composites with Improved Dielectric and Thermal Properties

High dielectric constant carbon nanotubes (CNTs) based polymer composites with enhanced thermal stability are promising materials for energy storage devices because of high breakdown voltage, ease in processing, enhanced flexibility and low cost. In the present work, 3-aminopropyltriethoxysilane (APTES) as additive was used along CNTs as filler and polymethylmethacrylate (PMMA) as matrix to enhance the dispersion of filler in matrix by increasing interfacial interaction between these two. These composites were synthesized by using solution casting method and monitored by FTIR spectroscopy whereas XRD and SEM analyses have been performed to explore the role of APTES in dispersion of CNTs. Significant improvement in the dielectric constant (Dielectric Constant: 40 at 1.6 wt% of CNTs) has been observed on adding small fraction of APTES-CNTs. An impressive increase in thermal stability of the composite was achieved because of APTES. It is noted that weight loss in APTES-CNTs/PMMA composite at 460 degrees C is less than that of CNTs/PMMA composite at 400 degrees C. Use of APTES-CNTs appears to be quite encouraging when the obtained values of dielectric constant and results of thermal stability of APTES-CNTs/PMMA are compared with those of pristine CNTs based PMMA (CNTs/PMMA) composites. Mechanism of APTES to control the agglomeration of CNTs in the composite is distinctive and effective in improving the features of composite.