Abstract: Disclosed is an adhesive formulation that, when stimulated by a defeatable stimulation, reduces an adhesive bonding force of the adhesive formulation and defeats the adhesive formulation. The adhesive formulation having (i) programmable linkages made from Diels-Alder adducts and (ii) a concentration of diene traps. The Diels-Alder adducts may be furan-maleimide, and the diene traps may be (i) latent alkenes and (ii) selected from functional groups that will create irreversible reations with furan. The adhesive formulation may be capable of being applied as a coating, and the adhesive formulation may be capable of being extruded. The adhesive formulation may have a bonding temperature between 75 and 120° C. And the defeatable stimulation could, for example, be a temperature above 130° C. The adhesive formulation also may contain several types of programmable linkages and diene traps.

Abstract: A pourable opaque centerport for solid propellant rocket motors and method for applying the same are disclosed. The pourable centerport inhibitor for solid propellant rocket motors has a curing system that includes a prepolymer and a curing agent. The prepolymer and the curing agent are combined to form a pourable polymeric binder that cures into an amorphous solid. The pourable centerport inhibitor also includes an opaque agent. The pourable centerport inhibitor may also include a plasticizer. The plasticizer, the prepolymer, and the curing agent are preferably the same type that is in the solid propellant with which it will be used in conjunction.

Abstract: A reversible viscosity reducing polymer is provided that has a crosslinkage between subunits inclusive of a single Diels-Alder Such a reversible viscosity reducing polymer is particularly well suited as a matrix material for a heterogeneous propellant. A process for forming a reversible viscosity reducing polymer inclusive of a single Diels-Alder linkage includes reacting a native crosslinkable moiety with a crosslinker moiety having a Diels-Alder reactive moiety of a diene or dienophile to form a Diels-Alder reactive moiety capped polymer subunit. The Diels-Alder reactive moiety capped polymer subunit is then exposed to a Diels-Alder reactant inclusive of a complementary Diels-Alder reactive moiety where the reactant also includes at least one conventional crosslinkable moiety to form a crosslinkable moiety capped polymer subunit. Reaction of the crosslinkable moiety capped polymer subunit is then reacted with a conventional multifunctional crosslinking agent.

Abstract: A reversible viscosity reducing polymer is provided that has a crosslinkage between subunits inclusive of a single Diels-Alder Such a reversible viscosity reducing polymer is particularly well suited as a matrix material for a heterogeneous propellant. A process for forming a reversible viscosity reducing polymer inclusive of a single Diels-Alder linkage includes reacting a native crosslinkable moiety with a crosslinker moiety having a Diels-Alder reactive moiety of a diene or dienophile to form a Diels-Alder reactive moiety capped polymer subunit. The Diels-Alder reactive moiety capped polymer subunit is then exposed to a Diels-Alder reactant inclusive of a complementary Diels-Alder reactive moiety where the reactant also includes at least one conventional crosslinkable moiety to form a crosslinkable moiety capped polymer subunit. Reaction of the crosslinkable moiety capped polymer subunit is then reacted with a conventional multifunctional crosslinking agent.

Abstract: A pourable opaque centerport for solid propellant rocket motors and method for applying the same are disclosed. The pourable centerport inhibitor for solid propellant rocket motors has a curing system that includes a prepolymer and a curing agent. The prepolymer and the curing agent are combined to form a pourable polymeric binder that cures into an amorphous solid. The pourable centerport inhibitor also includes an opaque agent. The pourable centerport inhibitor may also include a plasticizer. The plasticizer, the prepolymer, and the curing agent are preferably the same type that is in the solid propellant with which it will be used in conjunction.

Abstract: A binder matrix suitable for use in a gas generant composition, a gas generant composition including the binder matrix, and a related method of igniting such a gas generant composition are provided. The binder matrix includes a non-energetic binder material and dimethyl malonate non-energetic plasticizer and has a softening temperature above at least about 125° C. A gas generant composition including the binder matrix includes a non-energetic binder material such as cellulose acetate, dimethyl malonate non-energetic plasticizer, a fuel such as a nitramine fuel such as RDX, HMX or a combination thereof, and a stabilizer such as N-methyl-p-nitroaniline.

Abstract: A nitrate ester plasticized energetic composition in which the binder is made of, prior to curing, lower alkylene glycol prepolymer blocks end-capped with ethylene glycol monomers and/or oligomers. The end-capped prepolymer blocks are preferably difunctional or trifunctional. The lower alkylene glycol are preferably propylene glycol, butylene glycol, and/or copolymers thereof. The difunctional end-capped alkylene glycol prepolymer blocks are cured with a diisocyanate or polyisocyanate. In the case of a trifunctional (or higher functional) end-capped alkylene glycol prepolymer block, preferably a diisocyanate is used to effect crosslinking.

Abstract: A thermoplastic, elastomeric block copolymer comprises at least one poly(butadiene) and at least one pair of poly(lactone) blocks flanking the poly(butadiene) block. Each poly(lactone) block is derived from a lactone having between 8 and 18 carbon atoms in the lactone ring, such as &lgr;-laurolactone and 10-hydroxyl decanoic acid lactone. Alternative methods of making these block polymers are also disclosed. In the first procedure diethyl zinc reacts with the hydroxyl end group of a butadiene polymer to form an intermediate zinc alkoxide-tipped polybutadiene which functions as the active initiating species. The laurolactone polymer then grows off the hydroxyl end groups of the butadiene to form the desired ABA block copolymer. In another related procedure for making ABA block polymers, previously prepared difunctional hydroxyl-terminated polybutadiene blocks are linked with monofunctional poly(&lgr;-laurolactone) blocks using a diisocyanate and a catalyst.

Abstract: The present invention concerns an erosion resistant, low signature liner for solid propellant rocket motors and rocket motors having such a low signature liner. The liner combustion products in the exhaust plume have low visibility in the IR and visible light spectra which is essential for use in low signature solid propellant rocket motors. The liner also forms an in-situ protective layer at elevated temperatures for enhanced erosion resistance. These erosion resistant properties eliminate the need for supplemental case insulation which would contribute additional smoke and combustion products to the exhaust plume as well as add additional costs and inert weight to the motor.

Abstract: A formulation is provided which is capable of performing as a liner layer between a rocket motor casing and the propellant grain disposed within the interior of the rocket motor casing. The composition produces relatively little smoke during the operation of the rocket motor and is capable of securely bonding a wide range of conventional propellants to a wide range of conventional casings. In one preferred formulation, the liner consists of from from about 50% to about 75% oxygen containing polymer; from about 3% to about 15% curing agent; from about 5% to about 50% filler and from about 0.01% to about 0.5% cure catalyst.

Abstract: Improved thermoplastic elastomer compositions having improved processing and mechanical characteristics without requiring addition of excessive quantities of plasticizer comprise at least one thermoplastic elastomer loaded with a crystalline modifier having a relatively low melting point. The modifier can be liquid at the processing temperature, resulting in increased ease in handling of the product. An exemplary crystallizable modifier is an alkylated pentacycloundecane dimer.

Abstract: Crosslinkable compositions, a process for their preparation, and their use as casting compositions and for the production of mouldings. The composition can be homogeneously crosslinked at low temperatures. The compositions contain, as a binder, an adduct of maleic anhydride and a polymer based on 70-100% of butadiene and 0-30% of C.sub.2-12 olefins and/or C.sub.4-12 dienes. The compositions are employed as cable jointing compositions or for the production of mouldings.

Abstract: An improved multifunctional polyalkylene oxide binder is obtained by tailoring the cross-linking with a multifunctional polyol having a functionality of 3 or more and a molecular weight from about 12,000 to about 27,000 daltons. The binder is useful in forming castable propellants and plastic-bonded explosive compositions having high tensile strength and elongation and low volume dilatation.

Abstract: The invention relates to a combustion inhibitor composition intended to cover partly the surface of blocks of double-base propellant. The inhibitor composition of the invention includes an aliphatic polyurethane obtained by the reaction of at least one polyisocyanate with a mixture of at least one polyetherpolyol containing at least three hydroxy groups per molecule and at least one polymer containing two hydroxy groups per molecule. This difunctional polymer is chosen from lactone polymers, such as poly-.epsilon.-caprolactone and polytetrahydrofuran. The inhibitor composition may also contain gasifiable fillers and an aliphatic plasticizer. The composition has good discreteness properties, while retaining excellent mechanical properties. The present invention has particular application in the field of solid weapon propulsion.

Abstract: This invention relates to an improved procedure for selecting hydroxy-terminated polybutadiene in making crosslinked products therefrom. The procedure is based on the discovery that like appearing hydroxy-terminated polybutadienes differing by very small amounts of epoxy functionality behave very differently in crosslinked matrices.

Abstract: A combustion inhibitor for a double base propellant is described which comprises a polyurethane elastomer having in chemically combined form a compound which is an aliphatic polyester polyol or an aliphatic polyether polyol, or a mixture thereof, which compound contains 2-6 hydroxyl groups per molecule, and an aliphatic polyisocyanate. The inhibitor also contains 0.1-10 parts by weight of mineral fibers or thermostable organic fibers of length between 0.1 mm and 15 mm per 100 parts inhibitor. The inhibitor may contain an organic gasifiable charge and an aliphatic plasticizer.

Abstract: Disclosed is a thixotropic flame inhibitor for a rocket propellant grain luding an organic thixotrope in amounts from about 5 parts to about 30 parts into HTPB liquid polymer in amounts from about 70 parts to about 95 parts by stirring at elevated temperatures. After cooling the mixture to room temperature, appropriate quantities of di- or polyfunctional isocyanates and cure catalysts are added to promote cure at room temperature. Fine particulate matter may also be added to increase viscosity. The resulting formulation is a room-temperature curable, thixotropic mixture which will not flow under its own weight when applied to wettable non-horizontal surfaces in appreciable thicknesses, and which, when cured, is suitable as an inhibitor for composite solid rocket propellants. Thixotropy may be controlled by the level of organic thixotrope in the formulation while viscosity may be adjusted by the level of particulate filler; these parameters determine the allowable thicknesses from one-coat applications.

Abstract: Cure shrink-resistant missile motor cases are disclosed along with their method for construction. These cases comprise a matrix resin composition which includes a bisspiroortho carbonate as a fourth component, a curing agent of o-phenylenediamine boron trifluoride etherate as a third component, butanediol diglycidyl ether as a second component, and equal parts by weight of diglycidyl ether of bisphenol A and epoxidized dimer of oleic acid as a second component and additionally, they comprise, in combination therewith, a high strength fiber reinforcement material selected from the group consisting of fibers of glass, graphite, and poly-p-ethylene terephthalamide (Kevlar). The specific bisspiroortho carbonate which achieves an expansion of the matrix resin on polymerization or curing is 3,9-bis(5'-norbornene-2'-yl)-1,5,7,11-tetraoxaspiro [5.5]undecane.

Abstract: This invention involves the synthesis of a novel family of azido esters and their utilization as energetic plasticizers for advanced solid propellant compositions. This family includes as an illustrative member, the novel compound 6-azidohexyl-6-azidohexanoate.

Abstract: A binder for a polydiene composite propellant obtained by reaction of a combination of (a) a polydiene glycol having a hydroxyl group number of 1.8-2.1 and a number average molecular weight of 1,000-5,000, (b) a polydiene polyol having a hydroxyl group number from more than 2.1 to less than 4.0 and a number average molecular weight compound of 1,000-5,000, and (c) a diisocyanate.

Abstract: A curable binder for use in forming a castable propellant of the hydroxy-terminated polybutadiene type which uses a combination of two bonding agents, an aziridine polyester and an amine polyester. The amount of aziridine polyester is reduced by a factor of 3 to 4 compared to known systems. Improved propellant properties, including elongation at maximum load and at rupture, while maintaining comparable tensile strength and initial moduli, are obtained. A diisocyanate curing agent, an antioxidant such as di-tert-butylhydroquinone or phenyl-beta-naphthyl amine and combinations of antioxidants, and isodecyl pelargonate as a plasticizer, may be included.

Abstract: The present invention is a binder for a polydiene composite propellant comprising a small amount of binder and has as its object the production of the binder, which can provide stable physical properties between production lots and has a long pot life, and consists mainly of a polymer which has a predetermined molecular weight between crosslinks and which is obtained by reacting a combination of a polydiene glycol having a hydroxyl group number of 1.8-2.1 and a number average molecular weight of 1,000-5,000, a trifunctional crosslinking agent, a diisocyanate and a bifunctional chain extender. When a diene polymer having a functional group number of not more than 1 is additionally added to the above described combination, the elongation of the binder is improved and the use of a plasticizer can be reduced or eliminated.

Abstract: A solid propellant restrictor for preventing erosive burning in solid prolant grain critical areas is described. The restrictor is a mixture of hydroxyl-terminated polybutadiene with 1% by weight of dissolved 2,2'-methylene-bis(4-methyl-6-tert-butyl) phenol, dioctyl adipate, triethanolamine, ferric acetylacetonate, carbon black, aluminum oxide, silicon oxide, and toluene diisocyanate, curing at room temperature and illustrates superior hardening, adhesive, and application properties.

Abstract: A double base propellant grain inhibitor is comprised of a hydroxyl-termied polybutadiene polymer having from 2 to about 3 hydroxyl groups per average molecule and an approximate molecular weight of 2800 to 3600, an inert filler, a cross-linking agent, a thickening agent, an antioxidant, a curative, and a catalyst. When properly applied to the surface of a propellant grain, the inhibitor bond does not weaken with age and the inhibitor produces planar, no-cone grain burning having a constant chamber pressure during the burning of the propellant grain. A 1,4-butylene oxide-type polyether barrier layer consisting of a poly-1,4-butylene oxide diisocyanate with an approximate molecular weight of 850 to 1000, a diol curative, a triol cross-linker, and antioxidant and a cure catalyst can be added between the propellant grain and inhibitor to reduce propellant plasticizer migration.

Abstract: An epoxy adhesive for bonding solid fuel to its case in a rocket motor uses chopped aramid fiber and microfine silicon dioxide filler to provide insulating properties to the adhesive without the use of asbestos.