POLYURETHANE VARNISH PROVIDING STRONG ATTACHMENT OF ARMORED BIFUEL PROPELLANT CARTRIDGES TO ENGINE BODY Russian patent published in 2006 - IPC C09D175/06 

FIELD: rocket engineering.

SUBSTANCE: invention provides polyurethane varnish to be applied as sublayer to enhance adhesion of polymer compositions to the surface of removable charges armored with acrylate- or acetylcellulose-based compositions, to the surface of various types of alloyed steels, to titanium or aluminum bodies, to various types of heat-insulation coatings (including rubber, and glass-fiber materials) before gluing charges into engine body. Varnish is prepared by mixing adhesive agent with base and solidification catalyst, said adhesive agent being ethylene glycol/glycerol/sebacic acid condensation product, said base being combination of 2,4-tolylenediisocyanate and acetone, and said solidification catalyst being xylene or toluene solution of copper oleate used in amounts 0.5 to 2.0 wt %.

EFFECT: invention enables attachment of propellant cartridges to various parts of rocket engine with elevated adhesive strength and ensures level of adhesion, physico-mechanical, and ballistic characteristics during warranty-period storage.

1 tbl