The Dow Chemical Company

Dow Global Technolgoies LLC

E.i. Dupont De Nemours and Company

Michael E Rowland

Michael J Mullins

Thoi H Ho

H Craig Silvis

Clark H Cummins

Wendy D Hoenig

Osborne K McKinney

Che-I Kao

Kyle G Kummer

David A Babb

Morgan Mark Hughes

Pak-Wing Steve Chum

Shih-Yaw Lai

Stephen R Betso

Morris S Edmondson

Robert R Turley

David A Eversdyk

Lawrence T Kale

Che I Kao

Kenneth E Springs

Alfred F Castello

James J Hill

Chad A Strait

Stanley W Smith

Che-l Kao

Jerry W Soape

Robert B Combs

Richard C Abel, Jr

Coupled polymers are prepared by a process comprising heating an admixture containing (1) at least one polyolefin comprising ethylene and optionally at least one comonomer and (2) a coupling amount at least one poly(sulfonyl azide) to at least the decomposition temperature of the poly(sulfonyl azide) for a period sufficient for decomposition of at least 80 weight percent of the poly(sulfonyl azide) and sufficient to result in a coupled polymer; particularly where the polyolefin is the product of polymerization of ethylene and optionally at least one other alpha-olefin in the presence of a single site catalyst.

Rheology modification of polymers prepared using metallocenes

The subject invention is directed to a rheology-modified ethylene polymer having less than 0.5 weight percent gel, a composition distribution breadth index (CDBI) greater than 50 percent, and a molecular weight distribution (M /M ) of less than 4.0, which is characterized as having improved rheological performance and/or melt strength attributes relative to the unmodified polymer. The subject invention is further directed to polymer blends which comprise the rheology-modified polymers, and to a process for preparing the rheology-modified polymers.

Rheology-modified polyolefins

The invention includes a process of reacting a poly(sulfonyl azide) with a polymer comprising steps (a) forming a first admixture of a first amount of a first polymer or in a liquid which does not require removal from the polymer and a poly(sulfonyl azide); (b) then forming a second admixture of the first admixture with a second amount of at least one second polymer; and (c) heating the second admixture at least to the decomposition temperature of the coupling agent for a time sufficient to result in coupling of polymer chains. The invention further includes all compositions obtainable by processes of the invention as well as blends of those compositions with one or more polymers of compositions different from the first or second polymer or the product of a process of the invention. Additionally the invention includes articles made from compositions of the invention, and shaping those articles particularly by processes which comprise shaping the compositions in a melted state into an article, more preferably when the process comprises thermoforming, injection molding, extrusion, casting, blow molding, foaming or blowing as well as the use of the compositions in those processes.

Process of rheology modification of polymers

The invention includes a process of preparing a coupled polymer comprising heating an admixture containing (1) at least one polyolefin comprising ethylene and optionally at least one comonomer which is selected from alpha olefins having at least 3 carbon atoms, dienes and combinations thereof said polyolefin having a molecular weight distribution of less than or equal to about 3 and (2) a coupling amount at least one poly(sulfonyl azide) to at least the decomposition temperature of the poly(sulfonyl azide) for a period sufficient for decomposition of at least about 80 weight percent of the poly(sulfonyl azide) and sufficient to result in a coupled polymer; particularly where the polyolefin is the product of polymerization of ethylene and optionally at least one other alpha-olefin in the presence of a single site catalyst (transition metal like Va or Cr, metallocene or constrained geometry). The amount of poly(sulfonyl azide) is preferably from about 0.01 to about 5 weight percent of the polyolefin. The poly(sulfonyl azide)and polyolefin preferably react at a temperature at least the decomposition temperature and greater than about 150&deg; C. The invention also includes any composition made by the process of the invention and any article made from the composition as well as processes for making the articles, particularly melt processing (especially where the article is formed from a melt of a composition of the invention), more preferably selected by molding, blow molding or extrusion blow molding the composition. The invention also includes the use of a composition of the invention in any of these processes.

Elastomers with improved processability

The invention includes a process of reacting a poly(sulfonyl azide) with a polymer comprising steps (a) forming a first admixture of a first amount of a first polymer or in a liquid which does not require removal from the polymer and a poly(sulfonyl azide); (b) then forming a second admixture of the first admixture with a second amount of at least one second polymer; and (c) heating the second admixture at lest to the decomposition temperature of the coupling agent for a time sufficient to result in coupling of polymer chains. The invention further includes all compositions obtainable by processes of the invention as well as blends of those compositions with one or more polymers of compositions different from the first or second polymer or the product of a process of the invention. Additionally the invention includes articles made from compositions of the invention, and shaping those articles particularly by processes which comprise shaping the compositions in a melted state into an article, more preferably when the process comprises thermoforming, injection molding, extrusion, casting, blow molding, foaming or blowing as well as the use of the compositions in those processes.

A process for improving the green strength of ethylene/&agr;-olefin/diene polymers is described comprising (A) selecting an ethylene/&agr;-olefin/diene polymer having a Mooney viscosity at 125 C up to about 80 and a percent gel (% gel) up to about 30 percent and (B) partially crosslinking the ethylene/&agr;-olefin/diene polymer selected in step (A) to make a modified ethylene/&agr;-olefin/diene polymer satisfying the equations MV&lE;100 and

Methods for devolatilizing polymer solutions have been invented which include, in certain aspects, dissolving a viscous polymer in a solvent forming a polymer-solvent solution, introducing the polymer-solvent solution into a thermal dryer, heating or cooling the polymer-solvent solution in the thermal dryer forming product polymer with solvent removed and separated solvent (which may include other residuals), the separated solvent with other residuals if present vaporizing in the thermal dryer forming a vapor, removing the vapor from the thermal dryer, and discharging product polymer from the thermal dryer.

Polymer recovery

The invention includes a process of reacting a poly(sulfonyl azide) with a polymer comprising steps (a) forming a first admixture, hereinafter referred to as a concentrate, of a first amount of a first polymer or in a liquid which does not require removal from the polymer, hereinafter diluent, and a poly(sulfonyl azide); (b) then forming a second admixture of the first admixture with a second amount of at least one second polymer, hereinafter second polymer composition; and (c) heating the second admixture at least to the decomposition temperature of the coupling agent for a time sufficient to result in coupling of polymer chains. The diluent is preferably a non-volatile, non-polar compound such as mineral oil in which the poly(sulfonyl azide) is sufficiently miscible to disperse the poly(sulfonyl azide) in the second polymer.

The subject invention is directed to a rheology-modified ethylene polymer having less than 0.5 weight percent gel, a composition distribution breadth index (CDBI) greater than 50 percent, and a molecular weight distribution (M.sub.w /M.sub.n) of less than 4.0, which is characterized as having improved rheological performance and/or melt strength attributes relative to the unmodified polymer. The subject invention is further directed to polymer blends which comprise the rheology-modified polymers, and to a process for preparing the rheology-modified polymers.

A method of improving the oxidative thermal stability of ethylene polymers is disclosed. The method comprises removing residual unreacted monomer(s), solvent and thermally unstable species from the molten polymer. The resulting polymer is characterized by having an oxidative exotherm of not more than about 50 percent of the original polymer, as measured by differential scanning calorimetry.

Method of improving the oxidative thermal stability of ethylene polymers

Substantially linear ethylene polymers, e.g., polyethylenes prepared by constrained geometry catalysis (substantially linear ethylene), which are grafted with one or more unsaturated organic compounds containing both ethylenic unsaturation and a carbonyl group, e.g., maleic anhydride, exhibit desirable adhesive properties. These graft-modified substantially linear ethylene polymers also impart desirable compatibility and impact properties to various thermoplastic polymer blends.

Graft-modified substantially linear ethylene polymers and methods for

Aqueous dispersions of ethylene/.alpha.,.beta.-unsaturated carboxylic

A homogeneous, random interpolymer of ethylene and an alpha-olefinically unsaturated carboxylic acid or ester having a melt flow rate in the range of about 0.1 to about 300 g/10 minutes, as determined by ASTM D-1238 (190.degree. C./2160 g), is improved during its manufacture when made in a substantially constant environment in a stirred autoclave under substantially steady-state conditions of temperature, pressure, and flow rates, said temperature and pressure being sufficient to produce a single phase reaction, using a free-radical initiator, said improvement being obtained by the use of a minor amount of a telogenic modifier in the reaction mixture, the process being further characterized by the use of either, or both, of (a) a temperature which is lower than that which would be required without the presence of the telogen, or (b) a pressure which is higher than that which would be required without the presence of the modifier.

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Lake Jackson, TX, United States of America

Michael E Rowland