| 摘要 |
<p>Alumina or alumina-silica fibers useful for heat insulation purposes are made by dry spinning a spinning dope incorporating an aluminium compound, with or without a silicon compound, an organic polymer such as polyvinyl alcohol to aid fiber spinning and a zinc, cooper or tin salt to reduce dope viscosity and thus allow a higher concentration of aluminium in the dope and to produce a more stable alumina structure in the final fibers. After collection of the spun fibers, for example as a yarn or tow or as a non-woven web, the fibers are heated, usually in air to a temperature of 1,300oC to 1,600oC, to convert the aluminium and additional metal compounds and if necessary the silicon compound into their oxides and to burn off the organic polymer.</p> |
