| 摘要 |
<p>In the filtration of polyacrylonitrile-spinning solns. using inert plastic particles as filter aid, as in parent patent, the particles used are 20-200 mu polyamide powder. The polyamide powder is cheaper than the fluorocarbon polymers used previously and is available in different forms which can be chosen to suit the solvent used for the acrylonitrile and the other components to be removed. The polyamide powder can be regenerated and re-used by treating the filter residue with solvent esp. that used for the polyacrylonitrile soln. and the suspension formed wet sized.</p> |
