Optical properties of polymer nanocomposites

Abstract

Nanomaterials have emerged as an area of interest motivated by potential applications of these materials in light emitting diodes, solar cells, polarizers, light -stable colour filters, optical sensors, optical data communication and optical data storage. Nanomaterials are of particular interest as they combine the properties of two or more different materials with the possibility of possessing novel mechanical, electronic or chemical behaviour. Understanding and tuning such effects could lead to hybrid devices based on these nanocomposites with improved optical properties. We have prepared polymer nanocomposites of well-defined compositions and studied the optical properties of powders and their thin films. UV-vis absorption spectroscopy on nanocomposite powders and spectroscopic ellipsometry measurements on thin films was used to study the effect of interfacial morphology, interparticle spacing and finite size effects on optical properties of nanocomposites. Systematic shift in the imaginary part of the dielectric function can be seen with variation in size and fraction of the gold nanoparticle. The thickness of the film also plays a significant role in the tunability of the optical spectra.

Influence of silver ion reduction on electrical modulus parameters of solid polymer electrolyte based on chitosan-silver triflate electrolyte membrane

“…The origin of the intense colour of chitosan-silver triflate is attributed to the surface plasmon resonance (SPR), collective oscillation of free conduction electrons induced by an interacting electromagnetic field . Complex impedance plots of pure chitosan at selected temperatures [38]. The colour of metal nanoparticles depends on the shape and size of the nanoparticles and dielectric constant of the surrounding medium.…”

New Technology for the Synthesis of New Materials Based on Cellulose and Sorption of Noble Metals

“…The capacity of Au was 0.24 g Au/g ion-exchanger. In contact with the Au solution, Cell-1-Me-PVPJ changed color into brown-red, which concludes the creation of a gold nanoparticles (Srivastava et al, 2008). Synthesis of lignin 1-metylpoly-4-vinylpyridine iodide (Lig-1-Me-PVPJ) and tannin 1-metylpoli-4-vinylpyridine iodide (Tan-1-Me-PVPJ) was performed in the same manner as the synthesis of Cell-1-Me-PVPJ with the difference that Lig-PVP and Tan-PVP with methyl iodide was used.…”

Thermal and Conductivity Studies of VO2+ Doped Methacrylic Acid - Ethyl Acrylate (MAA:EA) Copolymer Films

“…The conductivity data of pure and VO 2+ doped MAA:EA copolymer at room temperature are presented in Table 1. Figure (6) shows typical Nyquist impedance plots of the 10 mol% of VO 2+ doped MAA:EA copolymer electrolyte film at different temperatures in the frequency and temperature ranges 1 Hz -1 MHz and 30 -70 ºC, respectively. The plots exhibit the general behavior of ionic solids with blocking electrode i.e., a semi-circle with an inclined spike.…”

“…Copolymer films are used for a number of technological and scientific applications due to their optical, thermal, mechanical, electronic and electrical properties. In recent years, there has been considerable interest in the preparation and characterization of copolymer films for their possible use as light stable color filters 5 , solar cells and optical sensors 6 . If the properties of the copolymer are tuned in right direction by adding suitable dopants, these copolymers could be best candidates for space applications 7 .…”