Showing papers by "Cabot Corporation published in 1998"

Effect of Polymer-Filler and Filler-Filler Interactions on Dynamic Properties of Filled Vulcanizates

Abstract: In the past few years, an enormous amount of work has been reported on the progress in the application of conventional fillers and the development of new products to improve the reinforcement of rubber, dynamic properties in particular. While all agree that the filler as one of the main components of the filled-rubber composite, has a very important role in improving the dynamic performances of the rubber products; many new ideas, theories, practices, phenomena, and observations about how and especially why the filler alters the dynamic stress-strain response have been presented. This, of course, suggests that not only is the real world of the filled rubber complex and sophisticated but also multiple mechanisms may be involved. However, it must be admitted that the possibility exists for explaining the effect of all fillers on rubber properties ultimately in similar and relatively nonspecific terms, i.e., the phenomenon related to all filler parameters should follow a general rule or principle. I...

Elastomer composite blends and methods for producing them

Abstract: Elastomer composite blends are produced by novel wet/dry mixing methods and apparatus. In the wet mixing step or stage, fluid streams of particulate filler and elastomer latex are fed to the mixing zone of a coagulum reactor to form a mixture in semi-confined flow continuously from the mixing zone through a coagulum zone to a discharge end of the reactor. The particulate filler fluid is fed under high pressure to the mixing zone, such as to form a jet stream to entrain elastomer latex fluid sufficiently energetically to substantially completely coagulate the elastomer with the particulate filler prior to the discharge end. Highly efficient and effective elastomer coagulation is achieved without the need for a coagulation step involving exposure to acid or salt solution or the like. Elastomer composites are produced. Such elastomer composites may be cured or uncured, and combine material properties, such as choice of filler, elastomer, level of filler loading, and macro-dispersion, not previously achieved. The coagulum produced by such wet mixing step, with or without intermediate processing steps, is then mixed with additional elastomer in a dry mixing step or stage to form elastomer composite blends. The additional elastomer to the coagulum may be the same as or different from the elastomer(s) used in the wet mixing step.

Oxygen-containing phosphor powders, methods for making phosphor powders and devices incorporating same

Abstract: The invention relates to phosphor powders and a method for making phosphor powders. The powders are oxygen-containing, such as metal oxides, borates or titanates and have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the continuous production of such powders. The invention also relates to improved devices, such as display devices, incorporating those shown by the figure, incorporating the phosphor powders.

Aerosol method and apparatus, particulate products, and electronic devices made therefrom

Abstract: Provided is an aerosol method, and accompanying apparatus, for preparing powdered products of a variety of materials involving the use of an ultrasonic aerosol generator (106) including a plurality of ultrasonic transducers (120) underlying and ultrasonically energizing a reservoir of liquid feed (102) which forms droplets of the aerosol. Carrier gas (104) is delivered to different portions of the reservoir by a plurality of gas delivery ports (136) delivering gas from a gas delivery system. The aerosol is pyrolyzed to form particles, which are then cooled and collected. The invention also provides powders made by the method and devices made using the powders.

A polishing composition including an inhibitor of tungsten etching

Abstract: A chemical mechanical polishing composition and slurry comprising a composition capable of etching tungsten and at least one inhibitor of tungsten etching and methods for using the composition and slurry to polish tungsten containing substrates.

Polymeric products containing modified carbon products and methods of making and using the same

Abstract: Various modified carbon products are disclosed which can form a part of a polymeric product containing the modified carbon product and a polymer. One type of modified carbon product disclosed is a carbon product having attached at least one organic group, monomeric group, or polymeric group. Another type of modified carbon product disclosed is a carbon product having attached a group having the formula: -Ar-CO2-R or -CnH2nCO2-R, where R is an organic group, monomeric group, or a polymeric group. The third type of modified carbon product contains a) a carbon product having attached at least one organic group directly attached to the carbon product, b) at least one ionic group, ionizable group, or a mixture thereof attached to the organic group, and c) at least one counter-ionic group or counter-ionizable group with at least one organic group, monomeric group, or polymeric group, or mixture thereof, where the counter-ionic or counter-ionizable group is attached to the ionic and/or ionizable group. A method of improving the dispersion of carbon products in polymers is also disclosed which involves dispersing the modified carbon products described above in a polymer to form a polymeric product.

Dispersible, metal oxide-coated, barium titanate materials

Abstract: Barium titanate-based particles having a coating comprising an oxide, hydrous oxide, hydroxide or organic acid salt of a metal other than barium or titanium, wherein at least 90 percent of said particles have a particle size less than 0.9 micrometer when said particles are dispersed by high shear mixing, useful in the fabrication of thin, fine-grained dielectric layers for multilayer ceramic capacitors with high breakdown voltage.

Polishing pad for a semiconductor substrate

Abstract: A polishing pad for polishing a semiconductor wafer which includes an open-celled, porous substrate having sintered particles of synthetic resin. The porous substrate is a uniform, continuous and tortuous interconnected network of capillary passage.

Particles having an attached stable free radical, polymerized modified particles, and methods of making the same

Abstract: A modified particle is disclosed wherein a particle has an attached group having formula (I), wherein A represents an aromatic group or an alkyl group; R1 represents a bond, an arylene group, an alkylene group (i), (ii) or (iii), wherein R4 is an alkyl or alkylene group or an aryl or arylene group; R?2 and R3?, which can be the same or different, represent hydrogen, an alkyl group, an aryl group, -OR?5, -NHR5, -NR5R5?, or -SR5, wherein R5, which is the same or different, represents an alkyl group or an aryl group; and SFR represents a stable free radical. Also disclosed is a modified particle or aggregate having attached a group having formula (II), wherein CoupA represents an Si-containing group, a Ti-containing group, a Cr-containing group or a Zr-containing group; R?8 and R9?, which can be the same or different, represent hydrogen, an alkyl group, an aryl group, -OR?10, -NHR10, -NR10R10?, or -SR10, wherein R10 represents an alkyl group or an aryl group; SFR represents a stable free radical; and n is an integer of from 1 to 3. A modified particle having an attached -SFR or -X-SFR is additionally disclosed. Also, modified particles with attached polymers are also disclosed as well as methods of making the modified particles.

A method to improve traction using silicon-treated carbon blacks

Abstract: A method of improving traction in an elastomer is disclosed. The method includes the step of adding an effective amount of an aggregate comprising a carbon phase and a silicon-containing species phase to an elastomer. Also disclosed is a method of improving the dynamic compliance of an elastomer which includes the step of adding an effective amount of an aggregate comprising a carbon phase and a silicon-containing species phase to the elastomer. The elastomer is preferably used in tires and results in improved traction, for instance, improved skid resistance on ice and snow.

Valve metal compositions and method

Abstract: Valve metal articles such as wire, sheet or powder having a second metal, preferably in a peripheral margin, prepared by coating the valve metal with a salt solution of the metal additive and heat treating in the presence of an oxygen getter to remove the oxygen from the valve metal and the anion of the metal salt to form the metal additive. For tantalum wire a preferred second metal is nickel. A preferred oxygen getter is magnesium. Nickel-containing tantalum wire is useful for enhance bonding to sintered pressed tantalum powder pellets in the production of electrolytic capacitors.

Method for making silver-containing particles

Abstract: Provided are silver-containing powders and a method and apparatus for manufacturing the silver-containing particles of high quality, of a small size and narrow size distribution. An aerosol is generated from liquid feed and sent to a furnace, where liquid in droplets in the aerosol is vaporized to permit formation of the desired particles, which are then collected in a particle collector. The aerosol generation involves preparation of a high quality aerosol, with a narrow droplet size distribution, with close control over droplet size and with a high droplet loading suitable for commercial applications.

Instability of thermocapillary–buoyancy convection in shallow layers. Part 2. Suppression of hydrothermal waves

Abstract: Hydrothermal-wave instabilities in thermocapillary convection are known to produce undesirable effects when they occur during the float-zone crystal-growth process, and perhaps in other situations. Suppression of the hydrothermal-wave instability produced in the model system of Part 1 (Riley & Neitzel 1998) is demonstrated through the sensing of free-surface temperature perturbations and the periodic addition of heat at the free surface along lines parallel to the crests of the hydrothermal waves.

Multilayer insulation composite

Abstract: The present invention is an insulating composite comprising (a) a first thermally reflective layer having a reflective surface and an opposing surface and (b) silica aerogel granules. The present invention further includes an insulating element in which the insulating composite is disposed within an air-impermeable container.

Process for producing low density gel compositions

Abstract: Processes for producing gel compositions comprising: esterifying a portion of the surface of a gel composition sufficient to produce a gel composition having a rod density of less than or equal to 0.27 g/cc, and/or a tap density of less than or equal to 0.2 g/cc through contact with at least one esterification agent and at least one catalyst. The processes may be utilized to produce low density gel compositions without the need for a supercritical drying step or thermal treatment.

Elastomeric compositions incorporating metal-treated carbon blacks

Abstract: Disclosed are elastomeric compositions including an elastomer and an aggregate comprising a carbon phase and a metal-containing species phase, optionally including a coupling agent. Also disclosed is an aggregate comprising a carbon phase and a metal-containing species phase. A variety of elastomers and formulations employing such elastomers are contemplated and disclosed. Elastomeric compositions incorporating an elastomer and the aggregate are also disclosed. Also disclosed are methods for preparing elastomers compounded with the aggregate, and methods of improving various properties of elastomeric compositions, such as abrasion resistance, hysteresis, wet skid resistance, and/or wet traction.

Analysis of flow between a wafer and pad during CMP processes

Abstract: In this paper, we summarize the development of a numerical model for the chemical mechanical planarization (CMP) process and experimentally investigate the effects of pad conditioning on slurry transport and mixing. A simplified two-dimensional numerical model of slurry flow beneath a stationary wafer was developed to determine the pressure and shear stress beneath a wafer. The initial results indicate that in the hydrodynamic regime a positive upward pressure is exerted on the wafer. We also examined three cases to study pad effects on slurry transport; polishing with an Embossed Politex pad, an unconditioned IC1000 pad, and a conditioned IC1000 pad. Cab-O-Sperse SC1 slurry was used in a 1:1.5 dilution with water. Mixing data show that conditioning has a negligible effect on the rate of slurry entrainment and mixing; however, conditioning has a large effect on the thickness of the slurry layer between the wafer and pad. Conditioning was found to increase the slurry thickness by a factor of two. In addition the gradients in slurry age beneath the wafer were compared among the three cases. The IC1000 pads supported a gradient in the inner third of the wafer only, while the Embossed Politex pad showed a linear gradient across the wafer implying it retains pockets of unmixed slurry in the embossed topography.

Nanoporous interpenetrating organic-inorganic networks

Abstract: Interpenetrating organic and inorganic networks with a maximum dimension of 100 nm are produced by: (1) mixing aqueous solutions or dispersions of organic polymers capable of forming polymer networks in aqueous phase, polymer precursors or the mixtures thereof and silicon dioxide components; (2) changing the pH value and/or thermally treating the aqueous solution or dispersion in order to form a gel made of interpenetrating organic and silica gel networks and (3) drying the gel

Multilayer composite materials with at least one aerogel-containing layer and at least one layer containing polyethylene terephthalate fibres, process for producing the same and their use

Abstract: Multilayer composite materials with at least one aerogel-containing layer and at least one layer containing polyethylene terephthalate fibres, process for producing the same and their use.

Tantalum metal power with controlled size distribution and products made therefrom

Abstract: A capacitor having a central electrode body having sintered metal anode with an electrode lead, the anode having a sintered product produced from a tantalum powder having deagglomerated particles such that the product of the volume mean diameter in microns multiplied by the specific surface area measured in m 2 /g is a number in the range of below about 25. Capacitors having a central electrode with the anode produced from a sintered product produced from a heat treated and oxidized tantalum powder wherein the oxidized particle size is greater than about 0.7 m 2 /g. Capacitors are defined in terms of anodes produced from powders having specified ratios of Scott Bulk Density to surface area or ratio of die fill rate to surface area.

Method for granulating aerogels

Abstract: A method is disclosed for the structural agglomeration of aerogel particles The method comprises the steps of feeding aerogel particles to a mixing apparatus A binder also is added to the mixing apparatus After thorough mixing agglomerates from the mixing apparatus optionally are separated according to their size

Toners containing positively chargeable modified pigments

Abstract: A toner composition is disclosed which contains modified pigment particles having attached organic groups and styrenic polymer-based resin particles. The organic groups which are attached to the pigment particles are positively chargeable. Developer compositions containing the toner compositions of the present invention and methods of imaging are also described which use the toner compositions of the present invention.

Methods for producing platinum powders

Abstract: Platinum powders and methods for producing platinum powders. The powders preferably have a small particle size, narrow size distribution and a spherical morphology. The method includes forming the particles by a spray pyrolysis technique. The invention also includes novel devices and products formed from the platinum powders.

Method for compacting aerogels

Abstract: A method of compacting aerogels into larger aerogel particles is disclosed. The method provides for molding small aerogel particles into larger aerogel particles and selecting a desired granular range of the molded aerogel particles. Additives, fillers, and binders may be added to the aerogel particles to achieve specific desired properties of the molded aerogel particles.

Charge-modified metal oxide particles

Abstract: The present invention relates to a charge-modified metal oxide and to toner and developer compositions incorporating same. The charge-modified metal oxide includes a metal oxide having a cyclic silazane treated therewith and optionally a second treating agent for imparting hydrophobicity. The charge-modified metal oxide have been found to provide effective free-flow attributes to the toner or developer composition and may further influence the charging characteristics of same.

Use of aerogels for deadening structure-borne and/or impact sounds

Abstract: Aerogel particles, in particular in the form of composite materials, are used to deaden structure-borne and/or impact sounds.

Carbon—Silica Dual Phase Filler: Part III. ESCA and IR Characterization

Abstract: A series of carbon—silica dual phase fillers have been analyzed using electron spectroscopy for chemical analysis (ESCA) and infrared spectroscopy (IR). These techniques reveal that the silicon in these materials is consistent with that in silica, and the predominant carbon in the carbon phase is similar to the predominant carbon in carbon black. ESCA and IR experiments demonstrate that the carbon—silica dual phase fillers are comprised of composite aggregates, each containing carbon and silica phases. In these dual phase aggregates the silica phase is intimately distributed with the carbon phase. Quantitative ESCA reveals that these dual phase fillers have excess oxygen over the expected stoichiometric amount for the silica present. This excess oxygen is likely due to oxygen groups on the carbon phase. Analysis of the ESCA oxygen Auger lines in combination with various chemical treatments substantiate the presence of carbon phase oxygen groups on the dual phase fillers. Quantitative ESCA in comb...

The use of modified carbon black in gas-phase polymerizations

Abstract: A process for the production of a polymer is disclosed wherein the polymerization occurs in a fluidized bed reactor or a reactor for the gas-phase production of a polymer and in the presence of a catalyst and a modified carbon black. Also disclosed are the polymer particles resulting from this process of the present invention and products made from the polymer particles of the present invention including hoses, such as radiator hoses, tires, and roofing material.

Process for producing metal oxide and organo-metal oxide compositions

Abstract: A process for producing metal oxide and/or organo-metal oxide compositions from metal oxide and organo-metal oxide precursors utilizing a rate modifying drying agent. The process allows metal oxide and/or organo-metal oxide compositions to be produced from a wide variety of metal oxide and organo-metal oxide precursors including metal halides and organometallic halides.