ISSN:
0308-0501
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Architektur, Bauingenieurwesen, Vermessung
,
Maschinenbau
Notizen:
We report here on the results of our continuing effort to study the flame-retardant mechanism of silica gel and potassium carbonate. These additives reduce the flammability of a wide variety of common polymers such as polypropylene, nylon, polymethylmethacrylate, poly(vinyl alcohol), and cellulose. In an effort to determine how these additives reduce polymer flammability, we have used electron paramagnetic resonance spectroscopy and solid-state 13C and 29Si nuclear magnetic resonance spectroscopy to characterize the combustion chars or residues. These data indicate that, in the case of poly(vinyl alcohol), the additives do not change the type of char formed, but they do change the rate of char formation relative to the rate of fuel generation. We also found that, using only CP/MAS 13C NMR, there can be significant intensity distortions which complicate interpretation, if the char is hydrogen depleted and contains paramagnetic centres. © 1998 John Wiley & Sons, Ltd.
Zusätzliches Material:
9 Ill.
Materialart:
Digitale Medien
Permalink
