کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5186951 1381117 2010 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Thermoreversible crosslinking of polyethylene enabled by free radical initiated functionalization with urethane nitroxyls
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Thermoreversible crosslinking of polyethylene enabled by free radical initiated functionalization with urethane nitroxyls
چکیده انگلیسی

This paper describes the functionalization of polyethylene with urethane derivatives of 2,2,6,6-tetramethylpiperidinyloxy (TEMPO), resulting in thermoreversible crosslinking of the polymer, which exhibits thermoplastic characteristics at sufficiently elevated temperatures. The urethane TEMPO adducts were synthesized by the reaction of 4-hydroxy TEMPO with various diisocyanates using appropriate catalysts, and were subsequently grafted to polyethylene using free-radical chemistry. A model study conducted on urethane isopropanol adducts confirmed that endothermic urethane reversion occurred with aromatic and alkyl diisocyanates at temperatures greater than 170 °C, and no exothermic urethane decomposition was observed. In contrast, urethane TEMPO adducts underwent exothermic decomposition at elevated temperatures, probably because of participation of the free nitroxyl species in urethane decomposition. Hence, the urethane TEMPO adducts were most effective when used as crosslinkers below their decomposition points.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 51, Issue 1, 6 January 2010, Pages 153-163
نویسندگان
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