Functional Photochromic Methylhydrosiloxane-Based Side-Chain Liquid-Crystalline Polymers

• Published in: Macromolecular chemistry and physics Vol. 215; no. 8; pp. 742 - 752
• Main Authors: Tóth-Katona, Tibor, Cigl, Martin, Fodor-Csorba, Katalin, Hamplová, Věra, Jánossy, István, Kašpar, Miroslav, Vojtylová, Terezia, Hampl, František, Bubnov, Alexej
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01.04.2014; Wiley; Wiley Subscription Services, Inc
• Subjects: Applied sciences; azo-polymers; Backbone; Birefringence; Chemical modifications; Dichroism; Exact sciences and technology; Grafting; Inorganic and organomineral polymers; Monomers; Nematic; nematics; Physicochemistry of polymers; Polymers; polysiloxanes; Self assembly; Spectra; Benzophenone derivatives; Photoisomerization; Thermotropic state; Photoinduced effect; Hydrosilylation; Cis trans isomerization; Experimental study; Phase transitions; Azo compound; self-assembly; Chemical modification; Optical texture; Side chain; nematics; Liquid crystal polymers; Preparation; polysiloxanes; azo-polymers; Birefringence; Light sensitive copolymer; Molecular reorientation; Kinetics; Siloxane copolymer
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.201300729

A new azobenzene‐group‐containing monomer and several respective functional side‐chain polymers grafted on a methylhydrosiloxane backbone (with two different degrees of poly­merization; with and without the addition of a photoreactive benzophenone derivative) are designed, synthesized, and characterized. The resulting materials clearly show self‐assembly behavior and possess a nematic liquid‐crystal phase over a broad temperature range, which extends below 0 °C. The optical properties of these new photo­chromic liquid‐crystalline materials are determined from the absorbance spectra of oriented samples and by photo­induced birefringence studies. The results indicate a considerable dichroism of the side‐chain liquid‐crystalline polymers (SCLCPs), and hence demonstrate their potential applicability for optical storage. A new azobenzene‐group‐containing monomer and respective functional side‐chain polymers grafted on a methyl­hydrosiloxane backbone are designed, synthesized, and characterized. The resulting polymers possess a nematic liquid‐crystal phase over a broad temperature range, which extends below 0 °C. The side‐chain liquid‐crystalline polymers exhibit considerable dichroism, and hence demonstrate their potential applicability for optical storage.