Hybrid Composite Yarn

Abstract

This invention is a hybrid composite yarn comprising: a first polyolefin yarn having >about 80% crystallinity according to WAXS measuring techniques; a second yarn taken from the group consisting of: glass; quartz; carbon; poly(p-phenylene terephthalamide), poly(m-phenylene terephthalamide); poly(vinyl alcohol); poly(1,4-phenylene-2,14-benzibisoxazole) (PBO); poly(1,4-phenylene-2,14-benzobisthiazole) (PBT); poly(benzimidizole) (PBI); poly(ethylene-2,14-naphthalate) (PEN); lyotropic liquid crystalline polymers formed by polycondensation of aromatic organic monomers to form aromatic polyesters, polyamides, aluminia-silicates, basalt, regenerated cellulosic materials and ultra-high molecular weight polyethylene (UHMWPE); and, wherein the first polyolefin yarn and the second yarn are physically combined to form a composite yarn having at least one of the following properties: tenacity greater than about 100% of the expected tenacity based on the volume fraction of the second; an initial modulus >about 100% of the expected modulus based on the volume fraction of the second; elongation at break <about 320% of the elongation at break of the second.

What is claimed is: 
     
         1 . A hybrid composite yarn comprising:
 a first polyolefin yarn having greater than about 80% crystallinity according to WAXS measuring techniques;   a second yarn differing from the first polyolefin yarn taken from the group consisting of glass, carbon, poly(p-phenylene terephthalamide) and basalt yarns; and,   wherein the first polyolefin yarn and the second yarn are physically combined to form a composite yarn having at least one of the following physical properties: greater than about 100% of the expected tenacity based on the volume fraction of the second yarn, an initial modulus greater than about 100% of the expected modulus based on the volume fraction of the second yarn and elongation at break less than about 320% of the elongation at break of the second yarn.   
     
     
         2 . The composite yarn of  claim 1  wherein the first polyolefin yarn is a multifilament having at least one of the following physical properties: a melt flow index between about 0.2 and about 50; a denier of less than about 300 grams/900 meters; a modulus equal to or greater than 40 g/d, an elongation of less than about 10% as measured by ASTM D2256; at least one of the filaments has a ratio of equatorial intensity to meridonal intensity greater than about 1.0 obtained from known small angle x-ray scattering (SAXS) measuring techniques. 
     
     
         3 . The composite yarn of  claim 1  wherein the first polyolefin yarn is polypropylene. 
     
     
         4 . The composite yarn of  claim 1  wherein the first polyolefin yarn is a blend of a first polyolefin and a second polymer taken from the group consisting of: thermoplastic, thermoset, and non-olefinic polymer. 
     
     
         5 . The composite yarn of  claim 1  wherein the second yarn is E-glass in a quantity in the range of 20% to 80% by weight. 
     
     
         6 . The composite yarn of  claim 5  wherein the second yarn is E-glass in a quality of about 60% by weight and at least one of the following physical properties: tenacity greater than about 100% of the expected tenacity based on the volume fraction of the second yarn, an initial modulus greater than about 100% of the expected modulus based on the volume fraction of the second yarn and elongation at break less than about 320% of the elongation at break of the second yarn. 
     
     
         7 . The composite yarn of  claim 1  wherein the second yarn is carbon yarn in a quantity in the range of 30% to 80% by weight. 
     
     
         8 . The composite yarn of  claim 7  wherein the second yarn is carbon yarn in a quantity of about 75% by weight and at least one of the following properties: tenacity greater than about 100% of the expected tenacity based on the volume fraction of the second yarn; an initial modulus greater than about 100% of the expected modulus based on the volume fraction of the second yarn; elongation at break less than about 320% of the elongation at break of the second yarn. 
     
     
         9 . The composite yarn of  claim 1  wherein the second yarn is basalt in a quantity of about 50% by weight and at least one of the following properties: tenacity greater than about 100% of the expected tenacity based on the volume fraction of the second yarn, an initial modulus greater than about 100% of the expected modulus based on the volume fraction of the second yarn and elongation at break less than about 320% of the elongation at break of the second yarn. 
     
     
         10 . The composite yarn of  claim 1  having:
 filaments included in the first polyolefin yarn; and, 
 a plurality of microfibrils included in at least one of the filaments wherein the filament includes a plurality of voids interspersed within the microfibrils, wherein both said microfibrils and voids are aligned substantially parallel to the longitudinal axis of the first polyolefin yarn. 
 
     
     
         11 . A hybrid composite yarn comprising:
 a first polyolefin yarn having greater than about 80% crystallinity according to WAXS measuring techniques;   a second yarn differing from the first polyolefin yarn taken from the group consisting of: glass; quartz; carbon; poly(p-phenylene terephthalamide), poly(m-phenylene terephthalamide); poly(vinyl alcohol); poly(1,4-phenylene-2,14-benzibisoxazole) (PBO); poly(1,4-phenylene-2,14-benzobisthiazole) (PBT); poly(benzimidizole) (PBI); poly(ethylene-2,14-naphthalate) (PEN); lyotropic liquid crystalline polymers formed by polycondensation of aromatic organic monomers to form aromatic polyesters, polyamides, aluminia-silicates, basalt, regenerated cellulosic materials and ultra-high molecular weight polyethylene (UHMWPE); and,   wherein the first polyolefin yarn and the second yarn are physically combined to form a composite yarn having at least one of the following properties: tenacity greater than about 100% of the expected tenacity based on the volume fraction of the second yarn; an initial modulus greater than about 100% of the expected modulus based on the volume fraction of the second yarn; elongation at break less than about 320% of the elongation at break of the second yarn.   
     
     
         12 . The hybrid composite yarn of  claim 11  wherein the first polyolefin yarn and the second yarn are physically combined to form a composite yarn having a tenacity in the range of 4.6 to 7.9 grams per denier. 
     
     
         13 . The hybrid composite yarn of  claim 11  wherein the first polyolefin yarn and the second yarn are physically combined to form a composite yarn having an elongation break in the range of 2.9 to 6.6 percent. 
     
     
         14 . The hybrid composite yarn of  claim 11  wherein the first polyolefin yarn and the second yarn are physically combined to form a composite yarn having a modulus in the range of 162 to 539 games per denier. 
     
     
         15 . A hybrid composite yarn comprising:
 a multifilament polyolefin yarn wherein at least one of the filaments has a ratio of equatorial intensity to meridonal intensity greater than about 1.0 according to SAXS measuring techniques   a second yarn differing from the first multifilament polyolefin yarn taken from the group consisting of glass, carbon and basalt yarns;   wherein the first multifilament polyolefin yarn and the second yarn are physically combined to form a composite yarn.   
     
     
         16 . The composite yarn of  claim 15  having a tenacity in the range of 4.6 to 7.9 grams per denier, an elongation break in the range of 2.9 to 6.6 percent and a modulus in the range of 162 to 539 games per denier. 
     
     
         17 . The composite yarn of  claim 15  wherein the second yarn is at least 90% carbon and the modulus of the composite yarn is in the range of 1.8 to 2.76 time the modulus of the first multifilament polyolefin yarn. 
     
     
         18 . The composite yarn of  claim 17  wherein the modulus of the first multifilament yarn is about 195 grams per denier. 
     
     
         19 . The composite yarn of  claim 15  wherein the second yarn is at least 90% carbon and the elongation at break of the composite yarn is in the range of 32% to 43% that of the first multifilament polyolefin yarn. 
     
     
         20 . The composite yarn of  claim 15  having:
 filaments included in the first polyolefin yarn; and, 
 a plurality of microfibrils included in at least one of the filaments wherein the filament includes a plurality of voids interspersed within the microfibrils, wherein both said microfibrils and voids are aligned substantially parallel to the longitudinal axis of the first polyolefin yarn. 
 
     
     
         21 . The composite yarn of  claim 15  wherein the second yarn is at least 90% carbon and the tenacity of the composite yarn is in the range of 74% to 83% that of the first multifilament polyolefin yarn.