کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5404257 | 1392774 | 2007 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Structural control of photoluminescence of four poly(urethane-urea-co-1,3,5-triazine)s: Synthesis and characterization
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Structural control of photoluminescence of four poly(urethane-urea-co-1,3,5-triazine)s: Synthesis and characterization Structural control of photoluminescence of four poly(urethane-urea-co-1,3,5-triazine)s: Synthesis and characterization](/preview/png/5404257.png)
چکیده انگلیسی
A series of segmented poly(urethane-urea)s containing 1,3,5 triazine in the hard block and hexamethylene spacers in the soft block was prepared. The hard to soft segment ratio was varied systematically, to afford a series of polymers in which the chromophore concentration varied from 4.2% to 18.1%. Although triazine emission is located in the UV region, the films with higher content of the chromophore emitted a visible blue light (425Â nm) when excited at the very red-edge of the absorption band. The photophysical properties of the materials were strongly dependent on the relative amount of triazine moieties along the main chain. Isolated moieties emit in copolymers with small amount of triazine groups, indicating that even though in solid state, these moieties tend to be apart. Two photophysical consequences were observed when the amount of triazine increases: there is some energy transfer process involving isolated moieties with consequent decrease of the lifetime and an additional red-edge emission attributed to aggregated lumophores. The mono-exponential decay observed for the isolated form is substituted by a bi-exponential decay of the aggregated species. The materials were not strong emitters, but since the N-containing triazine moieties are good electron transport groups, the polymers have potential application as electron transport enhancers in various applications.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Luminescence - Volume 124, Issue 2, June 2007, Pages 343-350
Journal: Journal of Luminescence - Volume 124, Issue 2, June 2007, Pages 343-350
نویسندگان
V.A.F. Deichmann, P.N. Lisboa-Filho, T.D. Martins, Teresa D.Z. Atvars, L. Akcelrud,