Subhotosh I Khan

6929848, Aug 16, 2005

Aug 26, 2002

10/227998

Michael R. Samuels - Wilmington DE, US
Subhotosh Khan - Midlothian VA, US
Mikhail R. Levit - Richmond VA, US

E.I. du Pont de Nemours and Company - Wilmington DE

B32B003/00
B32B005/06

428209, 4282974, 4282977, 428901, 174258, 174259

A sheet comprising thermoplastic polymer (TP) and short high tensile modulus fibers, in which the concentration of TP in the middle of the sheet is higher than at the surface of the sheet, useful for making prepregs with a thermoset resin.

7459044, Dec 2, 2008

Feb 3, 2005

11/050264

Subhotosh Khan - Midlothian VA, US
Michael Robert Samuels - Wilmington DE, US
Mikhail R. Levit - Glen Allen VA, US

E. I. du Pont de Nemours and Company - Wilmington DE

B05D 5/12
B05D 3/08

156 622, 156 628, 1563082, 1563084, 1563086, 156314, 156296, 442 67, 442118, 442164, 427118, 427220, 427221

A sheet comprising thermoplastic polymer (TP) and short high tensile modulus fibers, in which the concentration of TP in the middle of the sheet is higher than at the surface of the sheet, useful for making prepregs with a thermoset resin.

7771809, Aug 10, 2010

Dec 15, 2006

11/639468

Gary Lee Hendren - Richmond VA, US
Mikhail R. Levit - Glen Allen VA, US
Subhotosh Khan - Midlothian VA, US

E. I. du Pont de Nemours and Company - Wilmington DE

B32B 3/12

428116, 428118, 428902, 428 342, 428 357, 1621571, 1621573

This invention relates to a honeycomb comprising cells having edges forming a face of the honeycomb, the face defined by a plurality of points and having an area of curvature wherein at least two of the points are located in different tangential planes, the walls of the cells comprising 5 to 50 parts by weight thermoplastic material having a melting point of from 120 C. to 350 C. , and 50 to 95 parts by weight of a high modulus fiber having a modulus of 600 grams per denier (550 grams per dtex) or greater, based on the total amount of thermoplastic material and high modulus fiber in the walls; wherein less than 25 percent of the honeycomb cells in the area of curvature have a re-entrant angle of greater than 180 degrees. This invention also relates to articles including panels and/or aerodynamic structures comprising the honeycomb.

7771810, Aug 10, 2010

Dec 15, 2006

11/639548

Mikhail R. Levit - Glen Allen VA, US
Subhotosh Khan - Midlothian VA, US
Gary Lee Hendren - Richmond VA, US

E.I. du Pont de Nemours and Company - Wilmington DE

B32B 3/12

428116, 428118, 428902, 428 342, 428 357, 1621571, 1621573

This invention relates to a honeycomb including articles such as a panel or aerodynamic structure comprising matrix resin and paper, the paper comprising 50 to 80 parts by weight fibrous material having a modulus of 600 grams per denier (550 grams per dtex) or greater, 0 to 50 parts by weight powdered inorganic material, and 20 parts by weight or greater thermoplastic fiber, the improvement comprising the thermoplastic fiber is a binder for the paper and has a melting temperature above the curing temperature of the matrix resin; a glass transition temperature of greater than 100 C. , and the weight average molecular weight of the thermoplastic polymer in the thermoplastic fibers changes 20% or less after being maintained for 10 minutes at the melting temperature.

7771811, Aug 10, 2010

Dec 15, 2006

11/640045

Mikhail R. Levit - Glen Allen VA, US
Subhotosh Khan - Midlothian VA, US
Gary Lee Hendren - Richmond VA, US

E.I. du Pont de Nemours and Company - Wilmington DE

B32B 3/12

428116, 428118, 428902, 428 342, 428 357, 1621571, 1621573

This invention relates to an improved high performance honeycomb, methods for making the same, and articles including aerodynamic structures comprising the honeycomb, the honeycomb made with a paper that allows rapid impregnation of the honeycomb by structural resins while retarding excessive impregnation of node-line adhesives during manufacture. The honeycomb comprises a paper having a thickness of from 25 to 75 microns and a Gurley porosity of 2 seconds or greater and comprising high modulus fiber and thermoplastic binder having a melt point of from 180 C. to 300 C. , wherein at least 30 percent by weight of the total amount of thermoplastic material is in the form of discrete film-like particles in the paper, the particles having a film thickness of about 0. 1 to 5 micrometers and a minimum dimension perpendicular to that thickness of at least 30 micrometers.

7785520, Aug 31, 2010

Dec 15, 2006

11/639550

Subhotosh Khan - Midlothian VA, US
Gary Lee Hendren - Richmond VA, US
Mikhail R. Levit - Glen Allen VA, US

E.I. du Pont de Nemours and Company - Wilmington DE

B29C 59/00
B31F 1/00
B32B 3/12

264320, 428116, 264294, 264299, 264314, 264319, 26433111, 26433117, 264345, 264348, 156197, 156205, 156469, 156470, 156471, 156292

A honeycomb containing a thermoplastic material, high modulus fiber and thermoset resin has process steps of fracturing the thermoset resin, bending, molding or forming the honeycomb in a mold or over a form, heating to allow flow of thermoplastic material and cooling of the honeycomb to retain the shape of the mold or form.

7815993, Oct 19, 2010

Dec 15, 2006

11/640011

Gary Lee Hendren - Richmond VA, US
Subhotosh Khan - Midlothian VA, US
Mikhail R. Levit - Glen Allen VA, US

E.I. du Pont de Nemours and Company - Wilmington DE

B32B 3/12
B29C 73/06

428116, 156197, 493966

This invention relates to an improved flame retardant honeycomb comprising high modulus fiber and a flame retardant thermoplastic binder having a melt point of from 120 C. to 350 C. and a limiting oxygen index of 26 or greater, methods for making the honeycomb, and articles comprising the honeycomb. In a preferred embodiment the paper in the honeycomb has a flame classification of UL-94 V-0.

7927691, Apr 19, 2011

Apr 3, 2009

12/417691

Subhotosh Khan - Midlothian VA, US
Halvar Young Loken - Roseland VA, US

E.I. du Pont de Nemours and Company - Wilmington DE

C08L 23/00
C08L 27/06
C08L 27/08
C08L 27/12
C08L 29/04
C08L 33/20
C08L 61/06
C08L 63/00
C08L 63/02
C08L 63/04
C08L 67/02
C08L 75/04
C08L 77/06
C08L 77/10
C08L 81/04

4282974, 525113, 525114, 525134, 525142, 525144, 525145, 525185, 525186, 525421, 525423, 525429, 525438, 525442, 525445, 525454, 525455, 525456, 525480, 525523, 525528, 525531, 525533

A prepreg composite material that includes a fiber layer and a resin comprising a thermoset resin component, a curing agent and a fibrous micropulp. The micropulp component is an aramid fiber having a volume average length of from 0. 01 to 100 micrometers. The prepreg is useful in composite panel construction for minimizing fluid permeation into the cured structure. This prepreg is particularly suitable for making honeycomb sandwich panels. Film adhesives, liquid and paste resins containing aramid fiber micropulp are also disclosed.