کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
28921 44104 2007 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Photoinduced chirality in achiral liquid crystalline polymethacrylates containing bisazobenzene and azobenzene chromophores
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
Photoinduced chirality in achiral liquid crystalline polymethacrylates containing bisazobenzene and azobenzene chromophores
چکیده انگلیسی

One new liquid crystalline polymer containing bisazobenzene, poly[4-{(2-methacryloyloxyethyl)oxy}-4′-(4-nitrophenylazo)azobenzene] (PM2BAN), and two liquid crystalline polymers containing azobenzenes with spacers of two and six methylene units, poly[(4-(4′-nitrophenylazo)phenyloxy)x-methylene methacrylate] (PMxAN, x = 2, 6), were synthesized and characterized. The level and rate of photoinduced chirality were studied in films of the achiral polymers by irradiation with one handed circularly polarized light (CPL) at 442 nm. The results of circular dichroism (CD) suggest that left-CPL induces left helical arrangements of the polymers and right-CPL reverses the resulting arrangements into right helices. Photoinduced chirality in film of PM2BAN is increased with the increase of irradiation time. However, the level and rate of photoinduced chirality in film of PM2BAN are lower than those in films of PMxAN (x = 2, 6) at similar irradiation time. Compared with PM2AN, photoinduced CD values are higher in PM6AN. The results are discussed in terms of interactions between azobenzene chromophores and circularly polarized light.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Photochemistry and Photobiology A: Chemistry - Volume 185, Issues 2–3, 25 January 2007, Pages 338–344
نویسندگان
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