New liquid crystal polyethers and polyesters based on diphenylbutadiene mesogens
| ISSN: |
0887-624X
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| Keywords: |
nonlinear optics ; liquid crystal ; polymers ; photocrosslinking ; Chemistry ; Polymer and Materials Science
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| Source: |
Wiley InterScience Backfile Collection 1832-2000
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| Topics: |
Chemistry and Pharmacology
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| Notes: |
New liquid-crystalline (LC) polymers and small molecules have been synthesized based on the 1,4-diphenylbutadiene mesogen, a chromophore with χ(3) nonlinear optical properties. Polyethers were formed by phase-transfer reaction, and polyesters were prepared by Schotten-Bauman polymerization from these 4,4'-bisphenolic mesogenic structures. Liquid crystallinity was examined using differential scanning calorimetry (DSC) and optical microscopy. Most of the model compounds were found to be nematic. All mesomorphic polymers were nematic and displayed LC ranges of up to 50°C as well as a wide diversity of melting points. The melting points varied with the flexible (methylene) spacer length and were strongly dependent upon the presence of substituents in the mesogenic core. Crosslinking and cis-trans isomerization were observed under the influence of heat and ultraviolet radiation. © 1992 John Wiley & Sons, Inc.
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| Additional Material: |
3 Ill.
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| Type of Medium: |
Electronic Resource
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| URL: |