Effect of Blending of Cholesteric Cellulose Esters on the Pitch Height

Abstract

Butyric esters (BuPC) of hydroxypropylcellulose (HPC) with different degrees of substitution (DS) were obtained by the reaction of (2‐hydroxypropyl)cellulose with butyryl chloride. Blends of these BuPCs were obtained from ternary solutions by removal of the common solvent. The blends displayed thermotropic cholesteric mesophases and showed iridescent colors at ambient temperatures depending on the blend composition. The spectroscopic analysis of the blends showed systematic variations of the reflection colors with variations of the ratio of the blend components between the reflection colors of the pure blend components covering the range from 453–938 nm corresponding to pitch heights from 308–640 nm.

Supramolecular Nanocomposites: Dual‐Functional Cholesteric Hydroxypropyl Cellulose Esters Chemically Linked to Gold Nanoparticles

“…LCP of particular interest are thermotropic cholesteric LCPs which display reflective colors depending on the cholesteric pitch height. The cholesteric properties of the hydroxypropyl cellulose (HPC) ester can be modulated over a wide range by different lateral substituents, degree of substitution and blending . We recently introduced a cholesteric HPC ester with a controlled number of thioether groups .…”

Trend report macromolecular chemistry 2001

“…In blends of hydropropylcellulose butyroesters with different degrees of substitution the pitch of the cholesteric helix can be tuned 50. Reflection maximums of 453–938 nm were measured, which equals a pitch of 308–640 nm.…”