Ben B Duh

US Patent:

6403762, Jun 11, 2002

Filed:

Jun 26, 2001

Appl. No.:

09/891909

Inventors:

Ben Duh - Tallmadge OH

Assignee:

Shell Oil Company - Houston TX

International Classification:

C08F 600

US Classification:

528503, 528272, 528492, 528502

Abstract:

The present invention is an improvement upon the process for producing poly(trimethylene terephthalate) (PTT) wherein 1,3-propanediol (PDO), and optionally other diols, and an aromatic diacid or diester thereof, and optionally other diacids or diesters, are esterified or transesterified and the esterification or transesterification product is polycondensed to produce a prepolymer which is solid state polymerized to produce a polymer with a desired intrinsic viscosity (IV). The prior art process includes the SSP prereaction steps of crystallization, drying/annealing, and preheating. The improvement in the present invention comprises crystallizing and preheating the PTT polymer in one step, without a drying/annealing step in between. Thus, the prepolymer still has a substantial moisture content when it is first exposed to the SSP reaction temperature inside the crystallizer/preheater.

US Patent:

6441129, Aug 27, 2002

Filed:

May 15, 2001

Appl. No.:

09/858171

Inventors:

Ben Duh - Tallmadge OH
Ann Marie Corey - Akron OH

Assignee:

Shell Oil Company - Houston TX

International Classification:

C08F 600

US Classification:

528503, 528302, 528308, 5283086, 528481

Abstract:

The present invention is a process for producing poly(trimethylene terephthalate) (PTT) at an increased solid state polymerization rate, wherein 1,3-propane diol and an aromatic acid or a dialkyl ester thereof are esterified or transesterified, the esterification or transesterification product is polycondensed, and the polycondensation product is pelletized and then subjected to continuous solid state polymerization at a temperature of 200 to 225Â C. , preferably 210 to 225Â C. In one embodiment of the present invention, the temperature range is 200 to 220Â C. , and the pellet size of the polymer to be solid state polymerized is from 1. 0 to 1. 5 g/100. In another embodiment of the present invention, the solid state polymerization is carried out at 210 to 225Â C. for from 1 to 20 hours and then the temperature is increased to above the initial melting point of the polymer to produce a PTT polymer with an intrinsic viscosity of 1. 3 dl/g or greater.

US Patent:

6461575, Oct 8, 2002

Filed:

May 11, 1999

Appl. No.:

09/309921

Inventors:

Ben Duh - Tallmadge OH
Ye-Mon Chen - Sugar Land TX
Ann Marie Corey - Akron OH

Assignee:

Shell Oil Company - Houston TX

International Classification:

B01D 900

US Classification:

4222451

Abstract:

The pelletized product of melt condensation polymerization of 1,3-propanediol and terephthalic acid is crystallized in a vessel designed for continuous fluidized bed flow of the pellets in water at a temperature within the range of about 65 to about 100Â C. Hot-water treatment in the vessel permits crystallization of the pellets in a continuous operation and results in an increase of the crystallinity of the polymer to greater than about 35% and an increase in pellet density.

US Patent:

6610819, Aug 26, 2003

Filed:

May 30, 2002

Appl. No.:

10/158606

Inventors:

Ben Duh - Tallmadge OH
Robert Lawrence Blackbourn - Houston TX
Kathleen Suzanne Kiibler - Katy TX
Cecilia Zuqi Tse - Katy TX

Assignee:

Shell Oil Company - Houston TX

International Classification:

C08F 600

US Classification:

528499, 528503

Abstract:

The friability of crystallized PTT and solid stated PTT can be effectively reduced by lowering the temperature of the quenching water used in the pelletizing of the melt polycondensation polymer to between 32Â F. (0Â C. ) and 65Â F. (18Â C. ). In addition, the robustness of solid stated PTT pellets is effectively increased by using a prepolymer with a lower intrinsic viscosity (IV) or by increasing the IV of the solid stated product.

US Patent:

43749755, Feb 22, 1983

Filed:

Feb 2, 1982

Appl. No.:

6/345172

Inventors:

Ben Duh - Tallmadge OH

Assignee:

The Goodyear Tire & Rubber Company - Akron OH

International Classification:

C08G 6370

US Classification:

528272

Abstract:

A process for the continuous production of high molecular weight polyethylene terephthalate wherein the crystallized prepolymer having an intrinsic viscosity of at least 0. 3 is dried, preheated and polymerized in a single moving bed reaction zone. The method is characterized by an inert gas atmosphere and a reaction zone with a temperature gradiant ranging from about 170. degree. C. at the uppermost portion and a higher temperature of about 225. degree. C. at the lowermost portion.

US Patent:

57506442, May 12, 1998

Filed:

Oct 30, 1996

Appl. No.:

8/740547

Inventors:

Ben Duh - Tallmadge OH

Assignee:

Shell Oil Company - Houston TX

International Classification:

C08F 600
C08J 300

US Classification:

528481

Abstract:

A process is disclosed for the crystallization of a PEN prepolymer containing volatile components. The temperature is maintained at a temperature in the range of about 20. degree. C. above the Tg and about 10. degree. C. below the Tm while the PEN prepolymer is agitated. The PEN prepolymer is present as chips or pellets. The pressure during crystallization is maintained at a level higher than the vapor pressure of the volatile components in the PEN prepolymer chips or pellets.

US Patent:

42385938, Dec 9, 1980

Filed:

Jun 12, 1979

Appl. No.:

6/047849

Inventors:

Ben Duh - Tallmadge OH

Assignee:

The Goodyear Tire & Rubber Company - Akron OH

International Classification:

C08G 6326
C07D21130

US Classification:

528272

Abstract:

A high molecular weight polyester is produced by a two stage process: a partial melt process until the intrinsic viscosity of the polyester prepolymer reaches from about 0. 35 to about 0. 62 dl/g, and a solid state polymerization in a static bed until the intrinsic viscosity of the polycondensed polymer reaches at least 0. 70 dl/g. The melt process employs greater concentrations of initial acid in combination with a heel or the addition of make-up acid to achieve optimal carboxyl content for the polyester prepolymer capable of use in the static bed solid state polymerization. This prepolymer with an optimal carboxyl content achieves a maximum solid state polymerization rate in a static bed. The production of the high molecular weight polyester by the two stage process minimizes chemical instability and deleterious polymerization byproducts.

US Patent:

62973150, Oct 2, 2001

Filed:

May 11, 1999

Appl. No.:

9/309923

Inventors:

Ben Duh - Tallmadge OH
Ye-Mon Chen - Sugar Land TX
Ann Marie Corey - Akron OH

Assignee:

Shell Oil Company - Houston TX

International Classification:

C08L 6702

US Classification:

524605

Abstract:

The pelletized product of melt condensation polymerization of 1,3-propanediol and terephthalic acid (or alkyl ester thereof) is crystallized by immersion in water at a temperature within the range of 60 to about 100. degree. C. Hot-water treatment increases the crystallinity of the polymer to at least about 35% and increases pellet density to about 1. 33 g/cm. sup. 3.