Photo-Induced Optical Anisotropy and Morphological Study in Azobenzene Containing Block Copolymers

Abstract:

In this work, different types of nanostructured systems containing azobenzene groups were studied. With that aim, firstly, novel azo-functionalised block copolymers (BCP) were synthesized from epoxidized poly (styrene-b-butadiene-b-styrene) (SBS) modified with azobenzene units by one-step facile reaction between the epoxy groups and an azo-amine. The epoxy/amine reaction was verified by Fourier transform infrared spectroscopy. In addition, the effect of covalent attachment of the azobenzene moieties was investigated by analyzing the morphology and the optical anisotropic response of the resulting azo-containing BCP, with respect to solution mixing of the azobenzene as a guest in the BCP host without chemical bonding. On the other hand, epoxidized SBS was also used as template for the generation of nanostructured thermosetting epoxy matrices with azobenzene groups covalently linked. This BCP can self-assemble in the epoxy matrix to produce microphase-separated domains, thanks to the selective segregation of polystyrene blocks due to reaction induced microphase separation. In this case, the influence of the azobenzene content and the amount of epoxidized SBS on the generated morphologies and the photo-induced anisotropy was studied.

• Periodical: Materials Science Forum (Volume 714)
• Pages: 43-50
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.714.43
• Online since: March 2012
• Authors: Raquel Fernández, Iñaki Zalakain, José Angel Ramos, Loli Martin, Iñaki Mondragon
• Keywords: Azobenzene, Birefringence, Block-Copolymer, Epoxy, Microstructure

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