✦ LIBER ✦

Liquid crystal copolyethers with mixed mesogenic units and flexible spacers

✍ Scribed by A. Misyan; C. K. Ober

Publisher: Springer
Year: 1990
Tongue: English
Weight: 488 KB
Volume: 23
Category: Article
ISSN: 0170-0839
DOI: 10.1007/bf00419974

No coin nor oath required. For personal study only.

✦ Synopsis

Liquid crystalline copolyethers were prepared from monomer pairs selected from biphenol (BP), dihydroxy-a-methylstilbene (DHMS), and 2,2'-dimethyl-4,4'-dihydroxyazoxybenzene (DMAz) which were copolymerized with either dibromononane or dibromodecane spacers by phase transfer catalysis. Nematic LC mesophases were observed for most copolymers, but some exhibited dual mesophases. Smectic to nematic transitions were found in polymers with intermediate ratios of DMAz and DHMS with the nonamethylene spacer. These polymers showed excellent solubility in THF and CHC13. The longest mesophase range which consisted of two mesophases was found in a polymer composed of a 4:1 ratio of DHMS to BP and a nonane spacer.

📜 SIMILAR VOLUMES

Liquid crystal polymers: 19. Cholesteric

Liquid crystal polymers: 19. Cholesteric main chain polyesters with triad aromatic ester mesogenic units and chiral polyalkylene spacers

✍ Ho-Jin Park; Jung-II Jin; Robert W. Lenz 📂 Article 📅 1985 🏛 Elsevier Science 🌐 English ⚖ 630 KB

Comparative effects of resorcinol and bi

Comparative effects of resorcinol and bisphenol A in non-mesogenic units in liquid crystalline copolyesters containing a flexible spacer

✍ Rao, A. Kameswara ;Lenz, Robert W. ;Jin, Jung-Ii 📂 Article 📅 1989 🏛 Wiley (John Wiley & Sons) 🌐 English ⚖ 646 KB

Thermotropic polyesters with mesogenic g

Thermotropic polyesters with mesogenic groups based on substituted hydroquinone units and highly flexible siloxan spacer in the main chain

✍ C. Aguilera; H. Ringsdorf 📂 Article 📅 1984 🏛 Springer 🌐 English ⚖ 259 KB

Synthesis and characterization of a seri

Synthesis and characterization of a series of liquid crystal polymers with X-shaped two-dimensional mesogenic units

✍ Z. F. Li; L. Li; S. Y. Zhang; S. K. Cao; Q. F. Zhou 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 300 KB 👁 2 views

A series of liquid crystal polymers (LCPs) with X-shaped two-dimensional mesogenic units has synthesized via low temperature solution polycondensation. The liquid crystalline behaviors of the polymers were characterized using differential scanning calorimetry, polarized microscopy and X-ray diffract

Fibers from flexible liquid crystal main

Fibers from flexible liquid crystal main-chain polymers. II. Functional copolymers based on the 4,4′-dihydroxy-2,2′-dimethylazoxybenzene mesogen and spacers based on 2-dodecenedioic and nonanedioic acids

✍ C. H. Lin; M. Maeda; A. Blumstein 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 913 KB

Synthesis of new aromatic polyimides wit

Synthesis of new aromatic polyimides with various side chains containing a biphenyl mesogen unit and their abilities to control liquid-crystal alignments on the rubbed surface

✍ S. I. Kim; M. Ree; T. J. Shin; J. C. Jung 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 189 KB 👁 2 views

New poly(m-phenylene 4,4Ј-oxydiphthalimide)s containing various side chains, such as 6-(4-biphenylmethoxy)hexyloxy group and 6-(phenylphenoxy)hexyloxy isomers, were synthesized, giving thin films of a high quality. All the polyimides apparently were almost amorphous, but exhibited short-range orderi