Effect of Spacer Length on the Liquid Crystalline Property of Azobenzene-Containing ABA-Type Triblock Copolymers via ATRP

Xin De Tang; Long Cheng Gao; Nian Feng Han

doi:10.4028/www.scientific.net/KEM.428-429.67

Paper Titles

Green Synthesis of Liquid Crystal Intermediates the Preparation of Phenylacetylenes in Ionic Liquids
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Synthesis and Mesomorphic Property of 2,5-Aryl-1,3,4-Oxadiazole/Thiadiazole Derivatives Bearing a Terminal Thiophene Unit
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Mesomorphic Properties of Three-Benzene-Ring Containing Bent-Core Liquid Crystals 1,3-Phenylene-bis[4-(alkylcarboyloxyl)benzylideneamine]
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Synthesis and Mesogenic Properties of a Novel Hyperbranched Triphenylene-Based Discotic Liquid Crystal
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Effect of Spacer Length on the Liquid Crystalline Property of Azobenzene-Containing ABA-Type Triblock Copolymers via ATRP
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Synthesis of Liquid Crystalline Epoxy Resin p-BDEPB and Cure Kinetics with 3-MeTHPA
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Design, Synthesis and Properties of Asymmetric Substituted Coronene Derivative as Discotic Liquid Crystal
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Synthesis and Mesomorphic Properties of Three-Benzene-Ring Containing Bent-Core Liquid Crystal 1,3-Phenylene-bis[4-(nonylcarboyloxyl) benzylideneamine]
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Synthesis and Characterization of Novel Triphenylene Derivatives Having Carboxylic Acid Groups at the Peripheral Chains
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HomeKey Engineering MaterialsKey Engineering Materials Vols. 428-429Effect of Spacer Length on the Liquid Crystalline...

Effect of Spacer Length on the Liquid Crystalline Property of Azobenzene-Containing ABA-Type Triblock Copolymers via ATRP

Abstract:

The effect of flexible spacer length on the liquid crystalline property of ABA-type triblock copolymers containing azobenzene groups was investigated. For the study, the monomers, n-[4-(4-ethoxyphenylazo)phenoxy]alkyl methacrylates with varying methylene groups (n = 0, 2, 6) were used to synthesize a series of azobenzene-containing amphiphilic triblock copolymers PAnC-PEG-PAnC by atom transfer radical polymerization (ATRP). Differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and one-dimensional X-ray diffraction (1D WAXD) have shown that the glass transition temperatures of these copolymers decreased as n increases. PA0C-PEG-PA0C has no mesophase, while both PA2C-PEG-PA2C and PA6C-PEG-PA6C have a nematic mesophase. These differences derive of the length of spacer groups between the polymer main chain and side chain.