| 摘要 |
<p>Powders and beads, partic. of nitrocellulose, obtd. by the 'with solvent' technique, are subjected, after cutting and allowing to dry, to the following treatment in an aq. medium: (a) they are agitated in an aq. phase contg. >=1 combustion moderator, (b) the aq. phase is decanted and replaced by water without additive, (c) the beads and powders are agitated in water to eliminate solvents. The m.pt. of the combustion moderator or moderator mixt. is pref. less than 100 degrees C. The moderator is pref. a urea, nitric ester, phthalic ester, or cyclic ketone. The mass of water in steps (a) and (c) is pref. at least equal to the mass of powder, and the water temp. is close to the moderator m.pt. in step (a), and 60-70 degrees C in step (c). Step (a) pref. takes about 2 hrs. and step (c) 10 hrs. The method avoids the inconveniences of classical methods and the powders produced have ballistic properties analogous to those prepd. by classical techniques but posses superior chemical stability.</p> |
