Biopolymer Composites With High Dielectric Performance: Interface Engineering
01 Jan 2017-pp 27-128
TL;DR: In this article, the preparation and dielectric behavior of various biopolymer composites is presented, including metal nanoparticles and carbon-based nanofillers such as carbon nanotubes, graphene, etc.
Abstract: In recent years, there is a growing interest in studying the dielectric behavior of biopolymer composites due to their potential application as a dielectric material in various electronic devices such as microchips, transformers, and circuit boards. Conducting electroactive polymer composites have also been investigated for various potential applications which include biological, biomedical, flexible electrodes, display devices, biosensors, and cells for tissue engineering. In this chapter, the preparation and dielectric behavior of various biopolymer composites is presented. These biopolymer composites generally consist of nanoscale metal nanoparticles and carbon-based nanofillers such as carbon nanotubes, graphene, graphene oxide (GO), etc., dispersed into the polymer matrix. The physical and chemical properties of these fillers and their interactions with polymers have a significant effect on the microstructure and the final properties of nanocomposites. The biopolymer composites with excellent dielectric properties show great promise as an energy storage dielectric layer in high-performance capacitor applications such as embedded capacitors. This chapter highlights some of the examples of such biopolymer composites; their processing and dielectric behavior will be discussed in detail.
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Abstract: In the present investigation, attempt was made to prepare blend hydrogel by esterification of polyvinyl alcohol with gelatin. The blend hydrogel was further converted into films by the conventional solution-casting method. These films were characterized by FTIR, DSC, and X-ray diffraction studies. The refractive index and viscosity of different composition of the blends were measured in the solution phase of the material. The mechanical properties of the blend films were measured by tensile test. Swelling behavior of the blend hydrogel was also studied. The FTIR spectrum of the blend film indicated complete esterification of the free carboxylic group of gelatin. The DSC results indicate that the addition of gelatin with PVA changes the thermal behavior like melting temperature of PVA, which may be due to the miscibility of PVA with gelatin. The interaction of gelatin with PVA molecule changes the crystallite parameters and the degree of crystallinity. The crystallinity of the blend film was mainly due to gelatin. The comparison of viscosity indicated an increase in the segment density within the molecular coil. The results revealed the changes observed in the properties of the gel, and it enhances the gel formation at viscoelastic phase of the material. The blend film had sufficient strength and water-holding capacity. The results obtained indicated that the blend film could be used for various biomedical applications such as wound dressing and drug-delivery systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
148 citations
TL;DR: In this paper, the authors have carried out dielectric and AC conductivity studies for chitosan-based proton-conducting electrolytes using the solution cast method.
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TL;DR: Here CNXLs are utilized in a bottom-up hierarchical assembly to produce a macroscale material using single-stranded oligonucleotides with an amino modifier grafted on separate CNXL populations.
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