کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5186292 | 1381100 | 2007 | 13 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Novel phosphorus-modified polysulfone as a combined flame retardant and toughness modifier for epoxy resins
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A novel phosphorus-modified polysulfone (P-PSu) was employed as a combined toughness modifier and a source of flame retardancy for a DGEBA/DDS thermosetting system. In comparison to the results of a commercially available polysulfone (PSu), commonly used as a toughness modifier, the chemorheological changes during curing measured by means of temperature-modulated DSC revealed an earlier occurrence of mobility restrictions in the P-PSu-modified epoxy. A higher viscosity and secondary epoxy-modifier reactions induced a sooner vitrification of the reacting mixture; effects that effectively prevented any phase separation and morphology development in the resulting material during cure. Thus, only about a 20% increase in fracture toughness was observed in the epoxy modified with 20 wt.% of P-PSu, cured under standard conditions at 180 °C for 2 h. Blends of the phosphorus-modified and the standard polysulfone (PSu) were also prepared in various mixing ratios and were used to modify the same thermosetting system. Again, no evidence for phase separation of the P-PSu was found in the epoxy modified with the P-PSu/PSu blends cured under the selected experimental conditions. The particular microstructures formed upon curing these novel materials are attributed to a separation of PSu from a miscible P-PSu-epoxy mixture. Nevertheless, the blends of P-PSu/PSu were found to be effective toughness/flame retardancy enhancers owing to the simultaneous microstructure development and polymer interpenetration.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 48, Issue 3, 26 January 2007, Pages 778-790
Journal: Polymer - Volume 48, Issue 3, 26 January 2007, Pages 778-790
نویسندگان
R.M. Perez, J.K.W. Sandler, V. Altstädt, T. Hoffmann, D. Pospiech, M. Ciesielski, M. Döring, U. Braun, A.I. Balabanovich, B. Schartel,