Optical properties of (acetoxypropyl)cellulose mesophases: factors influencing the cholesteric pitch

The liquid‐crystalline properties of (acetoxypropyl)cellulose: Effect of chain length and degree of acetylation

“…The optical properties resulting from the arrangement of the chains in the cholesteric structure of both the thermotropic and lyotropic phases of APC have recently been reported. 16 For the thermotropic cholesteric mesophases of APC at a given temperature, a slight increase in the wavelength of the reflected light was observed for the samples with a lower weight average molar mass.…”

Characterization of Anisotropic Mesophase of Cellulose Acetate in Inorganic Solvent Mixture

“…As shown in Figure 9, the exponent x of these systems is about 3, in good accord with the result for cellulose/liq NH 3 /NH 4 SCN. 18 The coefficient a' becomes smaller with larger <(F)) for possibly same reason as the case of temperature dependence of P.…”

“…The pitch for the CA-SA/PPA/W system also depends on the polymer concentration CP. For many lyotropic liquid crystal systems, it is well-known that CP dependence of P at constant temperature can be represented as follows 18 1/P=a'C/+b (5) Here independent of CP. As shown in Figure 9, the exponent x of these systems is about 3, in good accord with the result for cellulose/liq NH 3 /NH 4 SCN.…”

Cellulosic Liquid Crystals

“…However, 2-ethoxypropyl cellulose shows a finite pitch at the clearing temperature, as is generally observed for lyotropic cellulose derivatives. X-ray investigations on thermotropic (acetoxypropyl) cellulose [75] For the latter derivative, a meridional reflection of the well-oriented fiber pattern was clearly visible, corresponding to a fiber repeat of 5.02 A (0.502 nm), which is the rise per glucose unit in cellulosics. From these data on the stretched sample, cluster formation in the thermotropic LC phase has been concluded for well-aligned chains (probably a 3/2 helix).…”

“…23) [Eq. (7)] established for lyotropic LC poly(alky1) glutamates holds also for different esters of HPC [75]. In addition, these derivatives exhibit a coinciding clearing and compensation temperature, T, and T,, which might just happen accidentally.…”