Synthesis and properties of photochromic liquid-crystalline copolymers containing both spironaphthoxazine and cholesteryl groups

Influence of chemical structure on the optical properties of new side-chain polymers containing cholesterol

“…However, the cholesteric range of PChA-10 with a DP of approximately 18-360 is constant at approximately 4-5°C. (Recently, contradicting the results reported by Freidzon etc., [11][12][13] other reports that PChA-10 [22] and PChA-5 [15] form only a smectic phase have appeared in the literature; we cannot determine the reason for this discrepancy.) Unlike PChA-5 and PChA-10, which exhibit liquidcrystal properties, PHET forms a cholesteric phase over a wide temperature range of T g = −27-84°C.…”

“…Numerous researchers have investigated the possibility of sidechain cholesteric polymers with cholesterol in different alkylene spacers. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] In particular, during the past few decades, many researchers have investigated the thermotropic cholesteric phase of flexible side-chain polymers with cholesterol, including polyacrylate, [11][12][13][14][15][16][17][18][19][20][21][22] polymethacrylate [11][12][13][16][17][18][19][20][21][22] and polysiloxane. [11][12][13][23][24][25] Side-chain homopolymers with a cholesteryl group in flexible spacers such as poly(cholesteryl-ω-acryloyloxyalkanoates) (PChA-n), [11][12][13] poly(cholesteryl-ω-methacryloylalkanoates) (PChM-n) …”

Synthesis and characterization of a series of side chain chiral smectic liquid crystalline elastomers

“…It may be concluded that the P 4 -P 6 molecules are more inclined to slantwise arrangement [26]. The P 0 -P 6 films showed another peak (first sharp, and then broad) at 2h of 20.44-20.75u (d54.75-4.81 Å , q51.304-1.323 Å 21 ) due to, first, high order (P 0 ) and then low order (P 1 -P 6 ) corresponding to the distance between the mesogenic side groups in the smectic layer [27]. As the level of crosslinking agent increased, these broad peaks became weaker; this is simply related to the difference between the intrachain scattering of the mesogenic repeat and the crosslinking unit.…”

“…As the level of crosslinking agent increased, these broad peaks became weaker; this is simply related to the difference between the intrachain scattering of the mesogenic repeat and the crosslinking unit. Combining POM with XRD shown that polymer P 0 was in a smectic B phase, elastomers P 1 -P 3 were in the smectic A phase, while P 4 -P 6 were chiral smectic C elastomers and P 7 displayed stress-induced birefringence [26,27]. It may be concluded that the chirality content of the chiral crosslinking agent has a strong effect on the polymer phase, and that increased content of crosslinker and chiral crosslinker with a long flexible chain favours formation of the chiral smectic C phase.…”

Photochromic chiral liquid crystalline systems containing spiro-oxazine with a chiral substituent I. Synthesis and characterization of compounds

“…We have been studying spiro-oxazine-containin g l R 5 n Å p liquid crystal materials systematically [8][9][10]. As far as we know, there has been no study of a photochromic where n Å is the average refractive index of the chiral chiral nematic liquid crystalline system doped with a nematic system.…”