Cholesteryl nonanoate blue phases

The strange blue phase liquid-crystalline condition of certain cholesteryl esters (nonanoate and myristate) exists over a very narrow temperature range between the cholesteric and isotropic phases. Its structure has now been probed by study of deuterium-labelled materials. The H n.m.r. spectra have been inter-... 

Figure 7.3. Heat capacity CpjR versus temperature T in cholesteryl nonanoate (CN). Helical phase (CH), blue phases (BPI, BPII, BPIII), isotropic phase (I) (from Thoen [26]).

Figure 10. General overview for the reduced heat capacity per mole Cp/R for a temperature range covering all phase transitions involving the blue phases in cholesteryl nonanoate (CN) [56].

Figure 11. Detailed plot of the enthalpy near the phase transition from the blue phase III to the isotropic phase in cholesteryl nonanoate (CN). Note that for clarity a large linear background 140 R (T-T ) with Tg = 90.73°C, has been subtracted from the direct data. The two vertical dashed lines indicate the width of the two-phase region [56],...

Blue phase AV=7.5xlO cm-3g- (cholesteryl oleate) [28] - 0.004 [27] (cholesteryl nonanoate) No data reported... 

Further specific volume measurements with chiral mesogens, cholesteric, and blue phases have been made [26-28, 159-161]. The influence of chiral dopants on C/A and C/N phase transitions has been studied [37, 162]. Earlier studies, particularly on cholesteric mesophases and their mixtures, have been published, for example, for cholesteryl acetate [163], cholesteryl myristate [53], cholesteryl nonanoate [54], cholesteryl... 

---