Patents by Inventor Aspy K. Mehta

Aspy K. Mehta has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20010053837
    Abstract: The copolymerization reaction of one or more olefin monomers, such as propylene, with &agr;,&ohgr;-diene units and the resulting copolymers are provided. More specifically, the copolymer may have from 90 to 99.999 weight percent of olefins and from 0.001 to 2.000 weight percent of &agr;,&ohgr;-dienes. The copolymer may have a weight average molecular weight in the range from 50,000 to 2,000,000, a crystallization temperature (without the use of externally added nucleating agents) in the range from 115° C. to 135° C. and a melt flow rate in the range from 0.1 dg/min to 100 dg/min. These copolymers may be employed in a wide variety of applications, the articles of which include, for example, films, fibers, such as spunbonded and meltblown fibers, fabrics, such as nonwoven fabrics, and molded articles. The copolymer may further include at least two crystalline populations.
    Type: Application
    Filed: February 20, 2001
    Publication date: December 20, 2001
    Inventors: Pawan Kumar Agarwal, Weiqing Weng, Aspy K. Mehta, Armenag H. Dekmezian, Main Chang, Rajan K. Chudgar, Christopher R. Davey, Charlie Y. Lin, Michael C. Chen, Galen C. Richeson
  • Publication number: 20010044506
    Abstract: This invention relates generally to crystalline propylene polymers, to methods for their production and to methods for their use in film applications. Specifically, this invention relates to crystalline propylene polymers comprising both propylene homopolymer and propylene copolymer. The compositions are prepared using metallocene catalyst systems comprising at least two metallocenes in a polymerization process that involves the sequential or parallel polymerization of propylene homopolymer and copolymer using propylene with a small amount of comonomer, preferably ethylene. The polymerization is catalyzed by a dual metallocene catalyst system. The resulting polymers have a broad, bimodal molecular weight distribution. The resulting polymers are excellent for use in the production of biaxially oriented films or non-oriented films.
    Type: Application
    Filed: March 6, 2001
    Publication date: November 22, 2001
    Inventors: Aspy K. Mehta, Michael C. Chen, James J. McAlpin, Anthony N. Speca, Kelly Tormaschy, Chon Y. Lin
  • Publication number: 20010039314
    Abstract: This invention relates generally to crystalline propylene polymers, to methods for their production and to methods for their use in film applications. Specifically, this invention relates to crystalline propylene polymers comprising both propylene homopolymer and propylene copolymer. The compositions are prepared using metallocene catalyst systems comprising at least two metallocenes in a polymerization process that involves the sequential or parallel polymerization of propylene homopolymer and copolymer using propylene with a small amount of comonomer, preferably ethylene. The polymerization is catalyzed by a dual metallocene catalyst system. The resulting polymers have a broad, bimodal molecular weight distribution. The resulting polymers are excellent for use in the production of biaxially oriented films or non-oriented films.
    Type: Application
    Filed: March 6, 2001
    Publication date: November 8, 2001
    Inventors: Aspy K. Mehta, Michael C. Chen, James J. McAlpin, Anthony N. Speca, Kelly Tormaschy, Chon Y. Lin
  • Patent number: 6306960
    Abstract: This invention relates generally to articles formed from polypropylene polymer foams and desirably isotactic polypropylene polymer foams. The polypropylene polymers are obtained from metallocene catalysis. The polypropylene polymer has molecular weight distributions and densities that fall within broad ranges. The polypropylene polymer foam may be prepared in a multiple stage polymerization process using the same metallocene component in at least two stages.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: October 23, 2001
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Pawan K. Agarwal, Aspy K. Mehta
  • Patent number: 6174930
    Abstract: This invention relates generally to foamable polypropylene polymer, and more particularly a foamable isotactic polypropylene homopolymer obtained from metallocene catalysis and to their methods of production and articles formed therefrom. The foamable polypropylene polymer has molecular weight distributions and densities that fall within broad ranges. The foamable polypropylene polymer may be prepared in a multiple stage polymerization process using the same metallocene component in at least two stages.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: January 16, 2001
    Assignee: Exxon Chemical Patents, Inc.
    Inventors: Pawan K. Agarwal, Aspy K. Mehta
  • Patent number: 5530054
    Abstract: Disclosed are hot melt adhesives comprising ethylene/alpha-olefin copolymers prepared with either supported or unsupported metallocene-alumoxane catalysts for applications in hot melt adhesives used in automotive product assembly, packaging and food packaging. These ethylene copolymers have weight average molecular weight ranging from about 20,000 to about 100,000 and comonomer weight percent ranging from about 6 to about 30. The hot melt adhesive composition includes the ethylene copolymer and a compatible tackifier at a ratio of tackifier to copolymer of from 70:30 to 30:70 and may also include up to 30 weight percent of a paraffinic and microcrystalline wax of the copolymer and tackifier.
    Type: Grant
    Filed: March 24, 1995
    Date of Patent: June 25, 1996
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Mun F. Tse, Aspy K. Mehta, Vince L. Hughes
  • Patent number: 5451450
    Abstract: Disclosed is an elastic film having improved properties. The elastic film can be blown, cast or cast embossed. The elastic film is processed by polymerizing olefins in the presence of a metallocene catalyst system.
    Type: Grant
    Filed: July 14, 1993
    Date of Patent: September 19, 1995
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Thomas C. Erderly, Aspy K. Mehta, Jeffrey A. Middlesworth
  • Patent number: 5358792
    Abstract: Disclosed are heat sealable compositions comprising: (a) from about 30 to about 70 weight percent a low melting polymer comprising an ethylene based copolymer having a density of from about 0.88 g/cm.sup.3 to about 0.915 g/cm.sup.3, a melt index of from about 1.5 dg/min to about 7.5 dg/min, a molecular weight distribution no greater than about 3.5, and a composition breadth index greater than about 70 percent; and, (b) from about 70 to about 30 weight percent of a propylene based polymer having from about 88 mole percent to about 100 mole percent propylene and from about 12 mole percent to about 0 mole percent of an alpha-olefin other than propylene. Further disclosed are films and articles made thereof.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: October 25, 1994
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Aspy K. Mehta, Michael C. Chen
  • Patent number: 5322728
    Abstract: Fiber with unique elastic properties comprising copolymer, of ethylene and comonomer, having density in the range of about 0.86 to about 0.93 g/cm.sup.3, MWD in the range of about 2 to about 3.5, melt index in the range of about 4 to about 1000, and SDBI less than about 25.degree. C.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: June 21, 1994
    Assignee: Exxon Chemical Patents, Inc.
    Inventors: Christopher R. Davey, Thomas C. Erderly, Aspy K. Mehta, Charles S. Speed
  • Patent number: 5266392
    Abstract: Compatibilized blends of polypropylene, linear low density polyethylene and a low molecular weight plastomer are disclosed. The blend preferably contains at least about 50 percent by weight of crystalline polypropylene, from about 10 to about 50 percent by weight of LLDPE dispersed in a matrix of the polypropylene, and a compatibilizing amount of an ethylene/alpha-olefin plastomer having a weight average molecular weight between about 5,000 to about 50,000, a density of less than about 0.90 g/cm.sup.3, and a melt index of at least about 50 dg/min. The blend is useful in the formation of melt spun and melt blown fibers. Also disclosed are spun bonded-melt blown-spun bonded fabrics made from the blends.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: November 30, 1993
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Louis P. Land, Angelo A. Montagna, Kenneth W. Bartz, Aspy K. Mehta
  • Patent number: 5246783
    Abstract: Disclosed are electrically conductive and semiconductive devices utilizing polymers having resistance to water treeing and good dielectric properties. The polymer comprises ethylene polymerized with at least one C.sub.3 to C.sub.20 alpha-olefin and optionally at least one C.sub.3 to C.sub.20 polyene. The polymer utilized has a density in the range of about 0.86 g/cm.sup.3 to about 0.96 g/cm.sup.3, a melt index in the range of about 0.2 dg/min to about 100 dg/min, a molecular weight distribution in the range of about 1.5 to about 30, and a composition distribution breadth index greater than about 45 percent. For the polymer utilized, the tree rating is generally less than about 40, the power factor is in the range of about 0.0002 to about 0.0005, and the dielectric constant is in the range of about 1.8 to about 2.4.
    Type: Grant
    Filed: August 15, 1991
    Date of Patent: September 21, 1993
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Lawrence Spenadel, Monica L. Hendewerk, Aspy K. Mehta
  • Patent number: 5241031
    Abstract: Disclosed is a process for improving the unload power of a precursor elastic film comprising orienting the film to a draw ratio in the range of about 2:1 to about 20:1 followed by annealing. Further disclosed is an elastic film oriented to a draw ratio in the range of about 2:1 to about 20:1 and comprising a copolymer of ethylene polymerized with at least one comonomer selected from the group consisting of C.sub.3 to C.sub.20 alpha-olefins and C.sub.3 to C.sub.20 polyenes, wherein the copolymer has a density in the range of about 0.855 g/cm.sup.3 to about 0.9 g/cm.sup.3, a melt index in the range of about 0.5 to about 50, with a composition distribution index at least about 45 percent.
    Type: Grant
    Filed: February 19, 1992
    Date of Patent: August 31, 1993
    Assignee: Exxon Chemical Patents Inc.
    Inventor: Aspy K. Mehta
  • Patent number: 4510078
    Abstract: Electrically conductive compositions comprising an ethylene polymer, a mineral filler and carbon black having a surface area greater than about 500 m.sup.2 /gram, these compositions being useful as extrudates about electrical conductors providing conductive shields thereon.
    Type: Grant
    Filed: August 15, 1983
    Date of Patent: April 9, 1985
    Assignee: Union Carbide Corp.
    Inventor: Aspy K. Mehta
  • Patent number: 4421678
    Abstract: Electrically conductive compositions comprising an ethylene polymer, a mineral filler and carbon black having a surface area greater than about 500 m.sup.2 /gram, these compositions being useful as extrudates about electrical conductors providing conductive shields thereon.
    Type: Grant
    Filed: December 29, 1980
    Date of Patent: December 20, 1983
    Assignee: Union Carbide Corporation
    Inventor: Aspy K. Mehta