Polymerica material suitable for making ammunition cartridge casings

Abstract

An ammunition article is provided which comprises a casing and a cap wherein the casing is formed from a polymeric material that has a room temperature notched Izod impact value greater than about 10 ft lbs/in and then has a ratio of notched Izod impact value at room temperature to notch Izod impact value at about −40° C. of less than about 4.

1 - 65 . (canceled) 
     
     
         66 . A method of improving the viscoelastic response of a polymeric ammunition cartridge casing material comprising a polyphenylsulfone by blending the material with a high modulus polymer, wherein said high modulus polymer is a rigid-rod polyphenylene polymer or copolymer. 
     
     
         67 . A blend comprising a polyphenylsulfone and a rigid-rod polyphenylene polymer or copolymer. 
     
     
         68 . The blend of  claim 67 , wherein the rigid-rod polyphenylene polymer or copolymer is a copolymer comprising the general structural formula: 
       
         
           
           
               
               
           
         
       
       wherein —Ar— is at least 0.1 mol % of the recurring units in (1) and wherein —Ar— is at least one arylene or heteroarylene repeat unit selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
       wherein one to three of the aromatic CH groups in (2) or (3) may be optionally replaced with N;
 the number average segment length of the arylene segments is greater than 4, the number average segment length of para-arylene repeat units is between 1 and about 8; the number average segment length of meta-arylene repeat units is greater than 1; 
 x is 0-4, and the pendent groups (A) are chosen independently from the group consisting of —F, —CN, —CHO, —COR, —CR═NR′, —OR, —SR, —SO 2 R, —OCOR, —CO 2 R, —NRR′, —N═CRR′, —NRCOR′, —CONRR′, and R, where R and R′ are selected independently from the group consisting of H, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl and substituted heteroaryl, and R and R′ if present together may form a bridging group; 
 Y is one or more divalent groups chosen from nil, —Z—, —Z-Ph-, and -Ph-Z-Ph-, where Z is a divalent group chosen from the group consisting of —O—, —S—, —NR—, —O(CO)—, —(CO 2 )—, —(CO)NH(CO)—, —NR(CO)—, phthalimide, pyromellitimide, —CO—, —SO—, —SO 2 —, —P(O)R—, —CH 2 —, —CF 2 —, and —CRR′— and where Ph is phenylene (ortho, meta or para); and wherein, if Y is nil, there are at least two different types of —Ar— repeat unit; 
 where at least 1 of every 100 repeat units has a pendent side group A; and 
 wherein n is greater than about 4. 
 
     
     
         69 . The blend of  claim 68 , wherein A is selected from the group consisting of alkyl, aryl, alkyl ketone, aryl ketone, alkoxy, aryloxy, alkylester, arylester, alkylamide and arylamide. 
     
     
         70 . The blend of  claim 69 , wherein A is selected from the group consisting of acetyl, benzoyl, carbomethoxy, formyl, phenoxy, phenoxybenzoyl, and phenyl. 
     
     
         71 . The blend of  claim 68 , wherein Y is nil and the polymer has the structure: 
       
         
           
           
               
               
           
         
       
       wherein the pendent group A′ is chosen independently from the group consisting of —F, —CN, —CHO, —COR, —CR═NR′, —OR, —SR, —SO 2 R, —OCOR, —CO 2 R, —NRR′, —N═CRR′, —NRCOR′, —CONRR′, and R, where R and R′ are selected independently from the group consisting of H, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl and substituted heteroaryl, and wherein R and R′ if present together may form a bridging group; and
 wherein n is greater than about 4. 
 
     
     
         72 . The blend of  claim 71 , wherein A′ is selected from the group consisting of alkyl, aryl, alkyl ketone, aryl ketone, alkoxy, aryloxy, alkylester, arylester, alkylamide and arylamide. 
     
     
         73 . The blend of  claim 72 , wherein A′ is selected from the group consisting of acetyl, benzoyl, carbomethoxy, formyl, phenoxy, phenoxybenzoyl, and phenyl. 
     
     
         74 . The blend of  claim 71 , wherein the meta-phenylene repeat units comprise at least about 10% of the repeat units. 
     
     
         75 . The blend of  claim 71 , wherein the metaphenylene repeat units comprise at least about 30% of the repeat units. 
     
     
         76 . The blend of  claim 68 , wherein Y is nil and the polymer has a structure selected from the group consisting of the following structures: 
       
         
           
           
               
               
           
         
       
       wherein the pendent groups A and A′ are chosen independently from the group consisting of —F, —CN, —CHO, —COR, —CR═NR′, —OR, —SR, —SO 2 R, —OCOR, —CO 2 R, —NRR′, —N═CRR′, —NRCOR′, —CONRR′, and R, where R and R′ are selected independently from the group consisting of H, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl and substituted heteroaryl, and wherein R and R′ if present together may form a bridging group; and
 wherein n is greater than 4. 
 
     
     
         77 . The blend of  claim 67 , wherein the rigid-rod polyphenylene polymer or copolymer is a soluble rigid rod polymer having repeat units of the formula: 
       
         
           
           
               
               
           
         
       
       wherein each R 1 , R 2 , R 3  and R 4  on each monomer unit, independently, is H or a solubilizing side group, where at least one out of one hundred of the monomer units incorporate a solubilizing side group and wherein the polymer has an intrinsic viscosity of greater than about 3 deciliters/gram when measured at 40° C. in a solvent selected from the group consisting of 0.05M lithium bromide in N-methylpyrrolidinone, N-methylpyrrolidinone, dimethylacetamide, phenylether, m-cresol, sulfuric acid, anisole, 5% N-methylpyrrolidinone/95% CHCl3, and chlorobenzene. 
     
     
         78 . The blend of  claim 77 , wherein at least about 30% of the monomer units incorporate a solubilizing side group. 
     
     
         79 . The blend of  claim 77 , wherein at least one of the R groups is: 
       
         
           
           
               
               
           
         
       
       wherein X is selected from the group consisting of hydrogen, amino, methylamino, dimethylamino, methyl, phenyl, benzyl, benzoyl, hydroxy, methoxy, phenoxy, —SC6 H5, and —OCOCH 3 . 
     
     
         80 . The blend of  claim 77 , wherein the rigid-rod polyphenylene polymer or copolymer is segmented. 
     
     
         81 . The blend of  claim 67 , wherein the rigid-rod polyphenylene polymer or copolymer has a room temperature flexural modulus of at least 500,000 psi (as measured by ASTM D790). 
     
     
         82 . The blend of  claim 67 , wherein the polyphenylsulfone has a room temperature notched Izod impact strength or value greater than about 10 ft-lb/in (as measured by ASTM D256-00) and that has a ratio of notched Izod strength value at room temperature to notched Izod impact value at about −40° C. of less than about 4. 
     
     
         83 . The blend of  claim 67 , which consists of the polyphenylsulfone and the rigid-rod polyphenylene polymer or copolymer. 
     
     
         84 . The blend of  claim 67 , which further comprises an additive selected from the group consisting of plasticizers, lubricants, molding agents, fillers, thermooxidative stabilizers, flame-retardants, coloring agents, compatibilizers, impact modifiers, release agents, reinforcing fibers, and combinations thereof. 
     
     
         85 . The blend of  claim 67 , wherein the amount of the rigid-rod polyphenylene polymer or copolymer is up to about 50% by weight. 
     
     
         86 . The blend of  claim 67 , wherein the amount of the rigid-rod polyphenylene polymer or copolymer is from about 5% by weight to about 50% by weight. 
     
     
         87 . The blend of  claim 67 , wherein the amount of the rigid-rod polyphenylene polymer or copolymer is from about 5% by weight to about 25% by weight. 
     
     
         88 . A method of producing a polymeric material useful for making an ammunition cartridge casing, said method comprising blending a high modulus polymeric material that has a room temperature flexural modulus of at least 500,000 psi (as measured by ASTM D790) with a resin material that has a room temperature notched Izod impact strength or value greater than about 10 ft-lb/in (as measured by ASTM D256-00) and that has a ratio of notched Izod strength value at room temperature to notched Izod impact value at about −40° C. of less than about 4,
 wherein the high modulus polymeric material is a rigid-rod polyphenylene polymer or copolymer material, and   wherein the resin material is a polyphenylsulfone material.