Photoinduced birefringence in blends of a polyurethane bearing azobenzene moieties and a poly(amide-imide)
Authors: Ceridório, Lucinéia; Cardoso, Marcos R; Pavinatto, Felippe; Carvalho, Antonio JF; Mendonça, Cleber R; Balogh, Débora T
Source: Polymer International, Volume 55, Number 9, September 2006 , pp. 1069-1074(6)
Publisher: John Wiley & Sons, Ltd.
Abstract:A polyurethane (MDI-DR19Cl) bearing azobenzene moieties was prepared by condensation of 4,4′-diphenylmethylenediisocyanate and an azobenzene compound, 2-chloro-4-nitro-4′-[bis-(2-hydroxyethyl)]amine-azobenzene (DR19Cl). Blends of MDI-DR19Cl and a poly(amide-imide) were prepared and characterized by UV-visible and Fourier transform infrared spectroscopy and by DSC. The purpose of using the blends was to overcome the lack of stability of cast films of pure MDI-DR19Cl, which tend to crack on storage under ambient conditions. This was successfully achieved and, depending on blend proportions, flexible self-standing films could be prepared after thermal treatment. Optical storage experiments performed with the blends and pure MDI-DR19Cl cast films showed a decrease in the remnant values of photoinduced birefringence in the blends (60 % for the blend with 5 wt% MDI-DR19Cl) compared to pure MDI-DR19Cl (75%), but, taking into account the low content of MDI-DR19Cl used, the results obtained are probably sufficient to show the viability of these blends in optical storage applications. Copyright © 2006 Society of Chemical Industry
Document Type: Research article
Publication date: 2006-09-01