Synthesis and Characterization of New Chiral Side Chain Liquid Crystalline Polyoxetanes

Abstract

Two series of the side chain liquid crystalline polyoxetanes were synthesized via cationic ring-opening polymerization of oxetane monomers bearing pendant mesogenic units including two chiral carbons. The first two polymers have only one pendant group in the repeating unit, whereas the second polymers have two mesogenic groups per repeating unit. The oxetane monomer bearing one mesogenic unit produced high molecular weight polymers, whereas the ones bearing two mesogenic units at the same carbon in the ring produced only oligomeric products. Thermal and liquid crystalline properties of the polymers were investigated by optical polarizing microscopy, differential scanning calorimetry (DSC), and small-and wide-angle X-ray diffractometry. All of the polymers, with the exception of only one polymer, formed liquid crystalline phases such as S A, SC*, and SI* phases in melts. The molecular arrangement in the smectic phases was interpreted as an intercalated bilayer structure. An attempt to study the ferroelectric properties of the polymers was made, but the results obtained were not satisfactory.

3,3-Bis(azidomethyl)oxetane (BAMO) Synthesis via Pentaerythritol Tosyl Derivates

“…The yields of 3,3-bis(tosylmethyl)oxetane reported in Table 3 refer to the pure product after crystallization from a methanol-acetone mixture in a vol/vol 6 : 1 ratio. The 3,3-bis(tosylmethyl) oxetane after crystallization melted in the temperature range of 114-116 8C, which coincides with the literature data [19].…”

Studies on the modification of poly(ω‐bromoalkyl‐1‐glycidylether)s with 4′‐methoxybiphenyl‐4‐oxy mesogenic groups

“…Oxetane polymerization has also received considerable attention,26–28 but its cationic polymerization again produces low‐molecular‐weight polymers with low yields.…”

Cascade hole transport in efficient green phosphorescent light‐emitting devices achieved by layer‐by‐layer solution deposition using photocrosslinkable‐conjugated polymers containing oxetane side‐chain moieties

“…2,7‐Dibromo‐9 H ‐carbazole 1 was synthesized by following the method in the literature. 29 3‐((6‐Bromohexyloxy)methyl)‐3‐methyloxetane 2 was also prepared according to the method in the literature 28. The reaction of 3‐((6‐bromohexyloxy)methyl)‐3‐methyloxetan‐3‐methyloxetane with 2,7‐dibromo‐9 H ‐carbazole yields 2,7‐dibromo‐9‐(6‐((3‐methyloxetan‐3‐yl)methoxy)hexyl)‐9 H ‐carbazole 3 in the presence of sodium hydride.…”

“…Compound 1 and 2 were synthesized by following the literature method 28, 29. The synthesis of the polymer 6 (POx‐I) was described in our previous work 22…”