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Rocket propellants
Nitrate/sugar-based propellants
Composite ammonium perchlorate-based propellants
1 - Epon 815 epoxy & curing agent U Composite ammonium nitrate-based propellants
Composite potassium perchlorate-based propellants
NOTE: These propellants are based on polyethylene sulfide rubbers mixed with ammonium perchlorate. According to the Thiokol Cehmical Corporation, liquid thiokol is produced by condensing ethylene chlorohydrin to dichlorodiethylformal, which is then treated with sodium polysulfide to obtain the finished product. The proportion for liquid thiokol to perchlorate is usually 20-40% thiokol to 60-80% perchlorate. There are six types of thiokol liquid polymer (LP): LP-2, LP-3, LP-31, LP-32, LP-33, and LP-8. According to Urbanski, the difference in the polymers lies in the degree of polymerization or cross-linking. Curing the thiokol polymers is done with a special curing compound, composition C, for 24 hours at 80oF, then pressed for 10 minutes at 287-310oF.. Proportions for LP to C is 100 parts LP to 10-15 parts C. The table for the liquid polymers is in parts by weight. The table for composition C is in percent.
NOTE: Whistle rockets must be made in the same way as a standard firework whistle, in the sense that it must be pressed very firmly for it to produce a whistling effect. The catalyst can be any metal oxide, though the usual ones used are titanium dioxide, copper oxychloride, and red iron oxide. DANGER: Whistle compositions should NEVER be rammed. They must be pressed or an explosion may result.
NOTE: Strobe rockets function similar to strobe stars in that the reaction oscillates between flash and smoulder phase. The first formula given to me by John Steinberg can have the barium sulfate replaced with various other metal sulfates to obtain different colors. DANGER: Copper sulfate can not be used in the first formula to produce a blue strobe. Copper sulfate absorbs moisture readily from the surrounding atmosphere. This moisture would then cause the magnesium and ammonium perchlorate to react producing heat, and eventually spontaneous combustion.
NOTE: The zinc/sulfur mixture is not a very efficient propellant due to its low specific impulse. In addition, the relatively high density of zinc adds much weight to the rocket, further reducing the propellant's effectiveness.
Last updated May 16, 1997. Copyright (C) 1997, Andrew Krywonizka. All rights reserved. |