کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5190781 | 1381216 | 2005 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Nitroxide-mediated polymerization of styrene initiated from the surface of fumed silica. Comparison of two synthetic routes
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Nitroxide-mediated free radical polymerization of styrene was performed from 13Â nm diameter fumed silica in two steps. First, an alkoxyamine, based on N-tert-butyl-N-(1-diethylphosphono-2,2-dimethylpropyl) nitroxide (DEPN) was covalently attached onto silica. Polystyrene chains with controlled molecular weights and narrow polydispersities were then grown from the alkoxyamine-functionalized nanoparticles surface in the presence of a 'free' sacrificial styrylDEPN alkoxyamine. Two strategies were investigated in order to immobilize the alkoxyamine initiator on the silica surface. In a first route, we synthesized a unimolecular alkoxyamine initiator carrying triethoxysilyl end groups reactive towards the silica surface. In a second route, the alkoxylamine was formed in situ by the simultaneous reaction of a polymerizable acryloxy propyl trimethoxysilane (APTMS), azobisisobutyronitrile (AIBN) and DEPN used as radical trap. In both cases, the grafting of both the initiator and the polystyrene chains was characterized and quantified by several techniques which allowed us to evaluate and compare the two strategies.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 46, Issue 19, 8 September 2005, Pages 8502-8510
Journal: Polymer - Volume 46, Issue 19, 8 September 2005, Pages 8502-8510
نویسندگان
Christèle Bartholome, Emmanuel Beyou, Elodie Bourgeat-Lami, Philippe Chaumont, Nathalie Zydowicz,