Keith E Stephens

US Patent:

6759454, Jul 6, 2004

Filed:

Feb 6, 2003

Appl. No.:

10/359906

Inventors:

Keith E. Stephens - Houston TX
Robert Q. Kluttz - Houston TX
Carl L. Willis - Houston TX

Assignee:

KRATON Polymers U.S. LLC - Houston TX

International Classification:

C08L 9500

US Classification:

524 68, 524 59

Abstract:

The present invention is a polymer modified bituminous composition having improved phase stability, heat aging and viscosity characteristics. The bituminous compositions are blends comprising bitumen and from about 0. 5 to about 25% of a novel anionic block copolymer where one of the blocks is a controlled distribution copolymer of a conjugated diene and a mono-alkenyl arene having a specific arrangement of the monomers in the copolymer block. The composition of the invention is useful for paving, roofing felts, water-proof membrane, adhesive, mopping asphalt, carpet backing and pipe coating applications.

US Patent:

7402619, Jul 22, 2008

Filed:

Mar 31, 2005

Appl. No.:

11/095368

Inventors:

Keith E. Stephens - Houston TX, US

Assignee:

Kraton Polymers U.S. LLC - Houston TX

International Classification:

C08L 95/00

US Classification:

524 68, 524 69, 524 70, 524 71, 524202, 524400, 524432

Abstract:

The present invention relates to a bituminous composition comprising a bituminous component, an elastomeric polymer component, and a specific cross-linking composition component comprising elemental sulfur, a sulfur-containing derivative, a sulfur activator, a fatty acid or fatty acid derivative and a polymeric carrier. Compositions according to the invention are particularly useful in preparing polymer-modified asphalt (“PMA”) for road applications.

US Patent:

7576148, Aug 18, 2009

Filed:

Nov 9, 2005

Appl. No.:

11/270079

Inventors:

Robert Q. Kluttz - Houston TX, US
Harriet J. S. Kendrick - Cypress TX, US
Keith E. Stephens - Houston TX, US

Assignee:

Kraton Polymers U.S. LLC - Houston TX

International Classification:

C08L 95/00

US Classification:

524 68

Abstract:

A process for preparing compatible, selectively hydrogenated block copolymer-modified bituminous compositions comprising blowing a mixture of the block copolymer and bitumen with an oxidizing gas at temperatures of at least 375 C. for at least 75 minutes. The modifying polymer is a selectively hydrogenated styrenic block copolymer and no blowing catalyst is required. Stable bituminous compositions comprising 6 to 25 parts by weight of block copolymer per 100 parts of asphalt are also provided as well as their application as roofing shingles.

US Patent:

7592381, Sep 22, 2009

Filed:

Nov 13, 2006

Appl. No.:

11/598511

Inventors:

Robert Q. Kluttz - Houston TX, US
Keith E. Stephens - Houston TX, US

Assignee:

Kraton Polymers U.S. LLC - Houston TX

International Classification:

C08L 95/00

US Classification:

524 68

Abstract:

The present invention is directed to a process for preparing a polymer modified bituminous binder composition in the substantial absence of crosslinking agents by heating a bitumen component in a stirred tank to a temperature from 185 C. to 221 C. ; adding a block copolymer composition to the bitumen component while the bitumen component is being stirred to form a homogeneous mixture of the bitumen component and the block copolymer composition; and continuing to stir the homogeneous mixture while maintaining the temperature from 185 C. to 221 C. for a period of time from 4 hours to 30 hours thereby forming a cured polymer modified bituminous binder composition. The block copolymer composition utilized in the process comprises a diblock copolymer comprising one block of a monovinylaromatic hydrocarbon and one block of a conjugated diene having a peak molecular weight from 30,000 to 78,000 and a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene block, and optionally one or more block copolymers comprising at least two blocks of monovinylaromatic hydrocarbon and at least one block of conjugated diene, the block copolymer selected from linear triblock copolymers having a peak molecular weight that is 1. 5 to 3. 0 times the peak molecular weight of the diblock copolymer, multiarm coupled block copolymers having a peak molecular weight that is 1. 5 to 9. 0 times the peak molecular weight of the diblock copolymer, and mixtures thereof, wherein each block copolymer has a vinyl content from 35 to 80 mol percent based on the number of repeat monomer units in the conjugated diene block, wherein when both (i) and (ii) are present in the block copolymer composition, the ratio of (i) to (ii) is greater than 1:1.

US Patent:

7622519, Nov 24, 2009

Filed:

Apr 29, 2008

Appl. No.:

12/111249

Inventors:

Robert Q. Kluttz - Houston TX, US
Keith E. Stephens - Houston TX, US

Assignee:

Kraton Polymers U.S. LLC - Houston TX

International Classification:

C08L 95/00

US Classification:

524 68

Abstract:

The present invention is directed to a process for preparing a polymer modified bituminous binder composition in the substantial absence of crosslinking agents by heating a bitumen component in a stirred tank to a temperature from 160 C. to 221 C. ; adding a block copolymer composition to the bitumen component while the bitumen component is being stirred to form a homogeneous mixture of the bitumen component and the block copolymer composition; and continuing to stir the homogeneous mixture while maintaining the temperature from 180 C. to 221 C. for a total period of time from 4 hours to 30 hours thereby forming a cured polymer modified bituminous binder composition. The block copolymer composition utilized in the process comprises one or more block copolymers having at least one monovinylaromatic block and either (I) at least one polybutadiene block having a vinyl content of less than 15 mol percent and at least one polybutadiene block having a vinyl content of greater than 25 mol percent or (II) at least one polybutadiene block having a vinyl content that tapers from a vinyl content of less than 15 mol percent at the first end adjacent to the monovinylaromatic block to a vinyl content that is greater than 25 mol percent at the second end which is furthest from the monovinylaromatic block and optionally at least one polybutadiene block having a vinyl content of less than 15 mol percent. The present invention is further related to an alternative to this process, a specific class of bituminous binder compositions and concentrates and a specific class of block copolymer compositions.

US Patent:

7728074, Jun 1, 2010

Filed:

Aug 5, 2009

Appl. No.:

12/536191

Inventors:

Robert Q. Kluttz - Houston TX, US
Keith E. Stephens - Waxahachie TX, US

Assignee:

Kraton Polymers U.S. LLC - Houston TX

International Classification:

C08L 53/02

US Classification:

525 99

Abstract:

A block copolymer composition including a diblock copolymer (I) having one block of a monovinylaromatic hydrocarbon and one block of a conjugated diene having a peak molecular weight from 30,000 to 78,000 and one or more block copolymers (ii) comprising at least two blocks of monovinylaromatic hydrocarbon and at least one block of conjugated diene, the block copolymer selected from linear triblock copolymers having a peak molecular weight that is 1. 5 to 9. 0 times the peak molecular weight of the diblock copolymer, and mixtures thereof, wherein the ratio of (i) to (ii) is greater than 1:1.

US Patent:

20080114099, May 15, 2008

Filed:

Nov 9, 2007

Appl. No.:

11/937948

Inventors:

Robert Q. Kluttz - Houston TX, US
Keith E. Stephens - Houston TX, US
Willem C. Vonk - Amsterdam, NL
Jan Korenstra - Amsterdam, NL

Assignee:

KRATON POLYMERS US LLC - Houston TX

International Classification:

C08L 95/00

US Classification:

524 61, 524 60

Abstract:

The present invention is directed to bituminous emulsions comprising bitumen, water, one or more emulsifiers and a block copolymer composition.

Address:

13720 Hollowgreen Dr, Houston, TX 77082

VIN:

1HD1BW5167Y035011

Make:

Cadillac

Model:

Escalade ESV AWD 4dr

Year:

2007