Surendra C Shah

US Patent:

6528151, Mar 4, 2003

Filed:

Apr 1, 1999

Appl. No.:

09/283765

Inventors:

Surendra P. Shah - Evanston IL
Yixin Shao - Evanston IL
Shashi Marikunte - Evanston IL

Assignee:

Northwestern University - Evanston IL

International Classification:

B32B 1302

US Classification:

428221, 4282947

Abstract:

An extruded fiber reinforced cement matrix composite having substantially improved tensile strength with strain hardening behavior and substantially improved tensile strain, and improved flexural properties in three-point bending is made by mixing cement, water, water soluble binder, and relatively short, discontinuous reinforcing fibers, preferably short polyvinyl alcohol fibers, to provide an extrudable mixture, the extruding the mixture to shape, and curing the cement.

US Patent:

20090229494, Sep 17, 2009

Filed:

Feb 6, 2009

Appl. No.:

12/322842

Inventors:

Surendra P. Shah - Evanston IL, US
Zoi S. Metaxa - Evanston IL, US

International Classification:

C04B 14/38
C04B 28/00

US Classification:

106816, 106638, 524 5, 977902, 977742

Abstract:

A composite cement material is prepared from cement material and carbon nanotubes, wherein the carbon nanotubes are present from about 0.02 wt % to about 0.10 wt % based on weight of cement material. The process for preparing such cement compositions includes sonicating a mixture of a surfactant, water, and carbon nanotubes; and blending the dispersion and the cement material to form a cementitious paste. The process may also include curing the cementitious paste. The composite cement materials are useful in a variety of cement applications where a reduction in nanoscale flaws and fractures is desired.

US Patent:

20120042806, Feb 23, 2012

Filed:

Jun 22, 2011

Appl. No.:

13/135004

Inventors:

Mark C. Hersam - Wilmette IL, US
Jung-Woo T. Seo - Evanston IL, US
Surendra P. Shah - Evanston IL, US
Zoi S. Metaxa - Kavala, GR

International Classification:

C04B 14/00
C01B 31/00
B82Y 30/00

US Classification:

106814, 106819, 423445 R, 4234151, 977742, 977902

Abstract:

Highly concentrated carbon nanotube or other nano-reinforcement suspensions and/or masses are prepared for use as admixtures in cement base materials to make cementitious composite materials.

US Patent:

58913742, Apr 6, 1999

Filed:

Sep 24, 1997

Appl. No.:

8/936349

Inventors:

Surendra P. Shah - Evanston IL
Yixin Shao - Evanston IL
Shashi Marikunte - Evanston IL

Assignee:

Northwestern University - Evanston IL

International Classification:

D01F 102

US Classification:

264108

Abstract:

An extruded fiber reinforced cement matrix composite having substantially improved tensile strength with strain hardening behavior and substantially improved tensile strain, and improved flexural properties in three-point bending. The composite is made by mixing cement, water, water soluble binder, and relatively short, discontinuous reinforcing fibers, preferably short poly vinyl alcohol fibers, to provide an extrudable mixture; then extruding the mixture to shape, and curing the cement.