This article is from the Space FAQ, by Jon Leech leech@cs.unc.edu and Mark Bradford tla@surly.org with numerous contributions by others.
Reference: "Shuttle Flight Operations Manual" Volume 8B - Solid Rocket
Booster Systems, NASA Document JSC-12770
Propellant Composition (percent)
Ammonium perchlorate (oxidizer) 69.6
Aluminum 16
Iron Oxide (burn rate catalyst) 0.4
Polybutadiene-acrilic acid-acrylonitrile (a rubber) 12.04
Epoxy curing agent 1.96
End reference
Comment: The aluminum, rubber, and epoxy all burn with the oxidizer.
 
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