Aspy K. Mehta

Bio: Aspy K. Mehta is an academic researcher from ExxonMobil. The author has contributed to research in topics: Polymerization & Polymer. The author has an hindex of 27, co-authored 60 publications receiving 2391 citations.

Electrical devices comprising polymeric insulating or semiconducting members

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 3 to C 20 alpha-olefin and optionally at least one C 3 to C 20 polyene. The polymer utilized has a density in the range of about 0.86 g/cm 3 to about 0.96 g/cm 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.

Fibers of polyolefin polymers

Abstract: Fiber with unique elastic properties comprising copolymer of ethylene and comonomer, having density in the range of about 0.86 to about 0.91 g/cm3, 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 28 °C.

Heat sealable blend of very low density polyethylene or plastomer with polypropylene based polymers and heat sealable film and articles made thereof

Abstract: Heat sealable compositions suitable for film and film structures comprise: (a) from 30 to 70 weight percent of a low melting polymer comprising an ethylene based copolymer having a density of from 0.88 g/cm3 to 0.915 g/cm3, a melt index of from 1.5 dg/min to 7.5 dg/min, a molecular weight distribution no greater than 3.5, and a composition distribution breath index greater than 70 percent; and, (b), being different from (a), from 70 to 30 weight percent of a propylene based polymer having from 88 mole percent to 100 mole percent propylene and from 12 mole percent to 0 mole percent of an alpha-olefin other than propylene.

Propylene impact copolymers

Abstract: This invention relates to propylene impact copolymer compositions. In particular, these unique and improved compositions can be produced using conventional, commercial-scale processes.

Elastic articles having improved unload power and a process for their production

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 C3 to C20 alpha-olefins and C3 to C20 polyenes, wherein the copolymer has a density in the range of about 0.855 g/cm3 to about 0.9 g/cm3, a melt index in the range of about 0.5 to about 50, with a composition distribution index at least about 45 percent.

Isotactic propylene copolymers, their preparation and use

Abstract: Unique copolymers comprising propylene, ethylene and/or one or more unsaturated comonomers are characterized as having: at least one, preferably more than one, of the following properties: (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 wt%, (iii) a skewness index, S?ix?, greater than about -1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that reports more gamma-form crystals than a comparable copolymer prepared with a Ziegler-Natta catalyst. These polypropylene polymers are made using a nonmetallocene, metal-centered, heteroaryl ligand catalyst. These polymers can be blended with other polymers, and are useful in the manufacture of films, sheets, foams, fibers and molded articles.

Catalyst composition comprising shuttling agent for ethylene multi-block copolymer formation

Abstract: A composition for use in forming a multi-block copolymer, said copolymer containing therein two or more segments or blocks differing in chemical or physical properties, a polymerization process using the same, and the resulting polymers, wherein the composition comprises the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.

Polyolefin adhesive compositions and articles made therefrom

Abstract: Embodiments of the present invention relate to article comprising 1) a functionalized component, 2) tackifier, and 3) an olefin polymer comprising one or more C3 to C40 olefins, optionally one or more diolefins, and less than 5 mole % of ethylene having a Dot T-Peel of 1 Newton or more, a branching index (g′) of 0.95 or less measured at the Mz of the polymer; and an Mw of 100,000 or less; where the functional component is selected from the group consisting of functionalized polymers, functionalized oligomers and beta nucleating agents; and where the Gardner color of the adhesive does not change by more than 7 Gardner units when the adhesive has been heat aged at 180° C. for 48 hours as compared to the Gardner color of the unaged composition.