Dielectric composites with a high and temperature-independent dielectric constant

Abstract

Dielectric composites made using P(VDF-CTFE) 88/12 mol% as polymer matrix and both micro-sized and nano-sized CaCu 3 Ti 4 O 12 (CCTO) particles as filler are developed. These composites exhibit high dielectric constant with a small dielectric loss. More importantly, it is found that the dielectric constant of these composites is almost independent of temperature from 25 ℃ to 125 ℃. Comparing the composites made using micro-sized CCTO particles, the composites made using nano-sized CCTO particles exhibit a smaller dielectric loss. The dielectric properties of these composites indicate that the nano-sized CCTO particles have a smaller dielectric constant than the micro-sized CCTO particles.

Metal-polymer nanocomposites with high percolation threshold and high dielectric constant

“…It has to be mentioned that the configuration of the stack of as-cast films used in the hot-press process is also very critical as demonstrated by the experimental results obtained in dielectric-dielectric composites (i.e., CCTOpolymer and BST-polymer composites). [18][19][20] Therefore, during the hot-press process used in this study, the stack of four layer as-cast films was configured in the following manner: the top of one as-cast film facing the top of the next as-cast film and the bottom of one as-cast film facing the bottom of the next as-cast film. The hot-press was carried out at 150 C, and afterword they were annealed after being placed between two glass plates at 140 C for 8 h.…”

Recent progress on nanostructured conducting polymers and composites: synthesis, application and future aspects

“…With the requirement of high-power, high-efficiency and low-cost capacitive storage system, there is great need for the development of dielectric materials with a high dielectric permittivity, low loss and high energy density [241][242][243][244][245]. Compared to inorganic dielectric materials (i. e., ferroelectric ceramics) [246][247][248][249], polymer-based dielectric materials have received tremendous attentions because of their excellent mechanical properties, high electric breakdown field and ease of synthesis [250][251][252][253][254].…”

Physical aspects of 0-3 dielectric composites

“…[27][28][29] Composites using CCTO have been widely studied. [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45] It should be mentioned that, in most of DDCs using nanosized ceramic fillers, the dielectric constant can only reach the value around 50 even for the composites with a volume fraction of filler up to 50 vol.%. 7 It is well known that the high filler content reduces the composite flexibility and results in weak mechanical properties, which can limit its applications.…”