Ppg Industries, Inc.

Ppg Industries Ohio, Inc.

Dow Corning Corporation

Thomas G Krivak

Laurence E Jones

Harold E Swift

Harlan B Johnson

Timothy A Okel

James L Boyer

Melvin P Wagner

Walter H Waddell

J Douglas Mansell

Larry R Evans

Dennis W Carson

James T Dew

Robert C Wang

Stanley A Heimburger

James Richard Hahn

Roger A Crawford

Clifford Carlton Reese

Gary Thomas Burns

Qin Deng

David A Longhini

Narayan K Raman

Shantilal M Mohnot

Patrick G Malloy

Da-Hung Yang

Robert C Dilmore

Laura M Randall

Robert H Fear

Paul A Beauregard

Larry E Jones

Joseph P Tultz

The present invention is directed to an attrition resistant carrier product such as silica. Further, this invention is directed to the use of a binder to improve the attrition resistance or reduce the friability of a carrier product such as silica. In an embodiment, the median particle size is from 125 to 300 microns. Selection of the binder is such that the presence and/or addition of the binder does not result in substantial modification of the physical properties of the silica. Suitable binders include Group I and Group II silicates, Group I and Group II aluminates, and mixtures thereof, as identified by the Period Table of Elements.

Attrition resistant carrier product

A method for the preparation of hydrophobic precipitated silica. The method comprises contacting an aqueous suspension of a hydrophilic precipitated silica with (1) a catalytic amount of an acid and (2) an organosilicon compound in the presence of (3) a water-miscible organic solvent in an amount sufficient to facilitate reaction of the hydrophilic precipitated silica with the organosilicon compound to form a hydrophobic precipitated silica.

Method for preparation of hydrophobic precipitated silica

Amorphous precipitated silica which may be used to form battery separators of very low specific resistance is characterized by (a) a CTAB surface area in the range of from 140 to 185 m.sup.2 /g; (b) a DBP oil absorption in the range of from 210 to 310 cm.sup.3 /100 g; (c) a mean ultimate particle size in the range of from 10 to 18 nm; (d) a total intruded volume in the range of from 2.6 to 4 cm.sup.3 /g; and (e) an intruded volume in the range of from 0.9 to 2 cm.sup.3 /g for pores having diameters in the range of from 20 to 100 nm.

Amorphous precipitated silica

Amorphous precipitated silica which may be used to form battery separators of very low shrinkage is characterized by (a) a BET surface area in the range of from 60 to 200 m.sup.2 /g; (b) a CTAB surface area in the range of from 40 to 150 m.sup.2 /g; (c) a DBP oil absorption in the range of from 180 to 300 cm.sup.3 /100 g; (d) a mean ultimate particle size in the range of from 20 to 30 nm; (e) a total intruded volume in the range of from 2.5 to 4 cm.sup.3 /g; (f) an intruded volume in the range of from 0.3 to 1.2 cm.sup.3 /g for pores having diameters in the range of from 20 to 100 nm; and (g) a pore diameter at the maximum of the volume pore size distribution function in the range of from 30 to 200 nm.

Amorphous precipitated silica having a low proportion of small pores as evidenced by low Sears surface areas are useful as reinforcing pigments for various rubbers.

Amorphous precipitated silica having a low proportion of small pores

Amorphous precipitated silica is characterized by a standard white area of less than 0.8 percent. The low standard white area is a characteristic of the silica which is indicative of high (i.e., very effective) dispersion when the silica is incorporated into organic rubber compositions which are cured. Cured organic rubber compositions comprising amorphous precipitated silica exhibit low white areas which indicate high dispersion of the silica in the compositions.

Amorphous precipitated silica characterized by high dispersion in cured

A statistically large population of particles of amorphous precipitated silica comprising pigmentary phase particles and glassy phase particles and having a glassy phase fraction in the range of from 0.3 to 30 area percent is useful as an abrasive for dentifrice compositions, especially toothpaste.

Amorphous precipitated silica abrasive

Cured tread rubber compositions of tires contain cured organic rubber, from 40 to 150 phr of reinforcing carbon black, and reinforcing reinforced amorphous precipitated silica wherein the silica has a surface area of from 160 to 340 m.sup.2 /g and a pore diameter at the maximum of the volume pore size distribution function of from 5 to 19 nm. The presence of such reinforcing silica provides improved tire performance characteristics, especially improved paved highway performance, to tires having treads of the cured tread rubber compositions.

Tire tread composition comprising highly reinforcing reinforced

Particles comprising particulate amorphous precipitated silica in association with from 5 to 10 percent by weight sodium sulfate and less than 10 percent by weight water, wherein the percentages are based on the weight of the silica, the sodium sulfate, and the water, which particles have a BET surface area of from 100 to 300 m.sup.2 /g, a total intruded volume from 1.8 to 3.6 cm.sup.3 /g, and a DBP oil absorption of from 180 to 320 cm.sup.3 /100 g, may be employed in microporous battery separators to introduce all or a portion of the desired sodium sulfate to the battery electrolyte. Moreover the enhanced amount of sodium sulfate enhances silica characteristics and battery separator production.

Precipitated silica having high sodium sulfate content

Cured tread rubber compositions of tires contain cured organic rubber, from 0 to 20 phr of reinforcing carbon black, and from 40 to 120 phr of reinforcing reinforced amorphous precipitated silica wherein the silica has a surface area of from 160 to 340 m.sup.2 /g and a pore diameter at the maximum of the volume pore size distribution function of from 5 to 19 nm. The presence of such reinforcing silica provides improved tire performance characteristics, especially improved paved highway performance, to tires having treads of the cured tread rubber compositions.

Elastomeric compositions contain crosslinked poly(diorganosiloxane) and reinforced precipitated silica having, on a coating-free and impregnant-free basis, a surface area of from about 220 to about 340 square meters per gram, a pore diameter at the maximum of the volume pore size distribution function of from about 9 to about 20 nanometers, and a total intruded volume of from about 2.6 to about 4.4 cubic centimeters per gram.

Silicone rubber reinforced with reinforced precipitated silica

Reinforced precipitated silica having, on a coating-free and impregnant-free basis, a surface area of from about 220 to about 340 square meters per gram, a pore diameter at the maximum of the volume pore size distribution function of from about 9 to about 20 nanometers, and a total intruded volume of from about 2.6 to about 4.4 cubic centimeters per gram, is produced by a process wherein precipitated silica is heavily reinforced using a multiplicity of precipitation and aging steps.

Reinforced precipitated silica

Described are high solids aqueous slurries of amorphous precipitated hydrated silica, which slurries are of relatively low viscosity. The slurry typically contains from about 40 to about 60 weight percent of hydrated precipitated high structure silica. The viscosity of the high solids slurry is less than about 1000 centipoises. Processes for producing the aqueous high solids silica slurry are disclosed. In one embodiment, a wet cake of amorphous precipitated hydrated silica is liquified and the liquified wet cake charged to a high intensity mill wherein the silica is wet milled until the median agglomerate particle size of the silica is between about 0.3 and about 3 microns. In a further embodiment, finely-divided dry amorphous precipitated silica is slurried in a dispersion mill to the desired solids level and this slurry charged to a high-intensity mill and wet milled therein until the aforesaid agglomerate particle size range is attained. The resulting high solids slurry can be shipped in bulk with only mild agitation to prevent setting. A dispersant may also be added to the slurry prior to milling to retard settling of the silica.

High solids aqueous silica slurry

Corrosion inhibiting calcium-containing amorphous precipitated silica is described. The silica is prepared by admixing simultaneously in a reactor aqueous alkali metal silicate, e.g., sodium silicate, acidifying agent, e.g., hydrochloric acid, and a water-soluble source of calcium, e.g., calcium chloride. The product contains from 6 to 9 weight percent calcium (as CaO). The silica product may be incorporated into a coating composition used for corrodible metallic surfaces.

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Harrison City, PA, United States of America

Thomas G Krivak