Título del libro: Elastomers: Types, Properties And Applications
Título del capítulo: Optical spectra of chiral elastomers during segregation and elastic processes
JUAN ADRIAN REYES CERVANTES; LAURA OLIVIA PALOMARES HERNANDEZ;
Autores externos:
Idioma:
Inglés
Año de publicación:
2012
Resumen:
Chiral elastomers (CEs) are rubbers formed by monomers of liquid crystals weakly cross-linked to polymeric chains, this union produces a flexible material whose molecular order is similar to cholesteric liquid crystals with the advantage that in this new material the responses to external stimuli are exceptionally large [1]. These stimuli could be mechanical, thermal, and electromagnetical with elastic and optical responses, giving rise to a wide range of applications such as artificial muscles, optical fibers, resonators and optical filters. In this chapter we focus in optical responses due to changes induced into the material by means of macroscopic deformations and chemical segregation processes due to their interesting applications. CEs, just like cholesteric liquid crystals [3] and chiral sculptured thin films [4], are structurally chiral materials that display the circular Bragg phenomenon (CBP) whereby a normally incident, circularly polarized plane wave of a specific handedness is highly reflected in a certain wavelength regime, whereas a similar plane wave but of the reverse handedness is transmitted. This polarization-discriminatory filtering characteristic of structurally chiral materials is very attractive in optical technology [5]. Additionally, materials with helical symmetry are unique periodic structures whose optical properties can be defined by equations which, for axial light propagation are exact and very simple, this analytical expressions give remarkable insight on the phenomena. Another outstanding property of CEs is segregation, which in fact is the ability to absorb and retain preferably left- or right-chiral molecules from a racemic solvent. Mechanical stress in CEs make feasible to control the optical properties for tunning the CBP and switching applications with the potential additional application of optical monitoring the chiral pump when the chemical segregation process is considered. Here, we revised in detail the representation of Marcuvitz-Schwinger with the transformation of Oseen, to calculate the band structure, transmittance and reflectance co-polarized and cross-polarized spectra of chiral-elastomer slabs. We study the modifications on optical spectra and band structure due to the action of some external agents. When an externally induced mechanical
Entidades citadas de la UNAM:
ISBN:
9781614701989
Editorial:
Nova Science Publishers, Inc. Nombre de la publicación:
Optical spectra of chiral elastomers during segregation and elastic processes
Página inicial:
97
Página final:
150
Tipo de producto:
Capítulo de un Libro
