Dielectric Properties of Nylon 11/CaCu 3 Ti 4 O 12 (CCTO) Nanocomposite Films with High Permittivity P. Thomas and A. Ashokbabu Dielectric Materials Division, Central Power Research Institute, Bangalore 560080, India R. S. Ernest Ravindran Department of Electronics and Communication Engineering, K L University Vaddeswaram, Guntur 522502, India Rahul Vaish School of Engineering, Indian Institute of Technology Mandi, Mandi 175005, India ABSTRACT Flexible nylon 11/CaCu 3 Ti 4 O 12 (CCTO) nanocomposite films (thickness ~100 μm) with varying CCTO nanoceramics (0 to 30 wt%) were fabricated by solution casting method followed by vacuum drying. The nanocomposites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy, and impedance analyzer to study their structural and dielectric properties. XRD analysis revealed the presence of γ-phase of nylon 11 both in as-cast film as well as in the composites. SEM micrographs indicated that the CCTO nanocrystals were distributed evenly throughout the nanocomposite films with less agglomeration. The room temperature dielectric permittivity was 168 at 50 Hz when the CCTO content increased to 30 wt% in the polymer and this was increased to 1007 at 423 K. Frequency independent dielectric behavior was observed for the frequency range of 100 kHz - 10 MHz. Temperature coefficient of permittivity showed that the permittivity of the nanocomposites is highly temperature dependent. Index Terms — nylon 11, CaCu 3 Ti 4 O 12 , dielectric permittivity, theoretical models 1 INTRODUCTION DIELECTRIC nanocomposites belong to a class of novel materials engineered for improved functions, performance for dielectrics and electrical insulation. The size reduction in the electronic components is associated with the development of newer and improved materials with high permittivity. Consequently, the usage of high permittivity materials in the application of electronic devices expands their efficiency [1, 2]. In the electronic packaging technology, the passive components such as capacitors, resistors and inductors were incorporated within the substrate as a layer instead of being used as discrete components to make the whole device compact and weight less. Among all, a distinct attention was given to capacitor, because huge quantities of them were employed in electronic devices and their unique nature of large energy storage [3]. Large number of literature reported high permittivity polymer-ceramic composites as promising materials for embedded device applications. Since the ceramic materials that were studied mainly contain lead as a major component, which is very hazardous and not environmental friendly, lead-free ceramics were sought after. In this context, BaTiO 3 ceramic which is lead-free and having relatively high dielectric permittivity compared with other ferroelectric ceramics was extensively studied to obtain high permittivity polymer-ceramic composite systems [4]. However, the materials developed for the capacitors required to possess low thermal coefficient of permittivity over a wide range of temperatures. In this regard, CaCu 3 Ti 4 O 12 (CCTO), a lead-free ceramic possessing giant permittivity (~10 4-5 ), which is nearly independent of the frequency (up to 10 MHz) and the temperature (100-600 K) has gained considerable attention over the recent years [5]. The CCTO nanoceramics, prepared via oxalate chemical route, were found to exhibit room temperature permittivity as high as 43,000 at 100 Hz [6]. Manuscript received on 8 June 2018, in final form 7 January 2019, accepted 8 January 2019. Corresponding author: P. Thomas. DOI: 10.1109/TDEI.2019.007578 568 P. Thomas et al.: Dielectric Properties of Nylon 11/CaCu 3 Ti 4 O 12 (CCTO) Nanocomposite Films with High Permittivity