A composite particle includes a discrete, hollow, ceramic spheroid and a fluoropolymer layer disposed thereon. The fluoropolymer is a homopolymer or copolymer of a perfluoroalkyl vinyl ether; a perfluoroalkoxy vinyl ether; at least one fluoroolefin independently represented by formula C(R).sub.2═CF—Rf, wherein Rf is fluorine or a perfluoroalkyl having from 1 to 8 carbon atoms and R is hydrogen, fluorine, or chlorine; or a combination thereof. Methods of making the composite particles, composite materials, and articles including them are also disclosed.

There is disclosed a talc particulate having a d.sub.50 of from about 0.5 to 5.0 μm and comprising less than about 500 ppm of particles having a particle size of equal to or greater than 45 μm and a shape factor equal to or greater than about 40. A process for making the talc particulate is also disclosed. The talc particulate may be used in polymer compositions as a filler from which polymer composites and articles may be formed.

There is disclosed a talc particulate having a d.sub.50 of from about 0.5 to 5.0 μm and comprising less than about 500 ppm of particles having a particle size of equal to or greater than 45 μm and a shape factor equal to or greater than about 40. A process for making the talc particulate is also disclosed. The talc particulate may be used in polymer compositions as a filler from which polymer composites and articles may be formed.

A highly purified diatomite composition may include greater than or equal to 90% silica, from about 0.5% to about 5% of a calcium-containing compound, and less than or equal to about 2% total of aluminum-containing oxides and iron-containing oxides. A method of making a highly purified diatomite composition may include providing a diatomite comprising at least 5% of a calcium-containing compound, calcining the diatomite, and acid washing the calcined diatomite. The calcined, acid-washed diatomite may include less than or equal to about 1% total of extractable aluminum-containing oxides and iron-containing oxides, and less than or equal to about 5% of the calcium-containing compound. The acid washing may include an acid selected from the group consisting of sulfuric acid (H.sub.2SO.sub.4), hydrochloric acid (HCl), and nitric acid (HNO.sub.3). The method may not include a flotation step.

A highly purified diatomite composition may include greater than or equal to 90% silica, from about 0.5% to about 5% of a calcium-containing compound, and less than or equal to about 2% total of aluminum-containing oxides and iron-containing oxides. A method of making a highly purified diatomite composition may include providing a diatomite comprising at least 5% of a calcium-containing compound, calcining the diatomite, and acid washing the calcined diatomite. The calcined, acid-washed diatomite may include less than or equal to about 1% total of extractable aluminum-containing oxides and iron-containing oxides, and less than or equal to about 5% of the calcium-containing compound. The acid washing may include an acid selected from the group consisting of sulfuric acid (H.sub.2SO.sub.4), hydrochloric acid (HCl), and nitric acid (HNO.sub.3). The method may not include a flotation step.

The present invention provides a novel surface-modified inorganic substance obtained by modifying the surface of an inorganic nitride or an inorganic oxide with a boronic acid compound, and a heat dissipation material, a thermally conductive material, and a lubricant which use the surface-modified inorganic substance. The present invention also provides a method for manufacturing the surface-modified inorganic substance, and provides, as a novel method for modifying the surface of an inorganic substance selected from an inorganic oxide and an inorganic nitride with an organic substance, a method for modifying the surface of an inorganic nitride or an inorganic oxide with an organic substance that includes making a contact between the inorganic nitride or the inorganic oxide with a boronic acid compound.

The present invention provides a novel surface-modified inorganic substance obtained by modifying the surface of an inorganic nitride or an inorganic oxide with a boronic acid compound, and a heat dissipation material, a thermally conductive material, and a lubricant which use the surface-modified inorganic substance. The present invention also provides a method for manufacturing the surface-modified inorganic substance, and provides, as a novel method for modifying the surface of an inorganic substance selected from an inorganic oxide and an inorganic nitride with an organic substance, a method for modifying the surface of an inorganic nitride or an inorganic oxide with an organic substance that includes making a contact between the inorganic nitride or the inorganic oxide with a boronic acid compound.

A radiation-scattering composition, comprising a plurality of colloidal crystals or aggregates of colloidal crystals, each said crystal comprising radiation reflecting particles in a colloidal array and radiation absorbing particles dispersed in the crystals. The composition scatters radiation in a wavelength band in substantially all directions and absorbs radiation.

A radiation-scattering composition, comprising a plurality of colloidal crystals or aggregates of colloidal crystals, each said crystal comprising radiation reflecting particles in a colloidal array and radiation absorbing particles dispersed in the crystals. The composition scatters radiation in a wavelength band in substantially all directions and absorbs radiation.

Provided herein is a process for treating dregs for the application thereof as vulcanization activator of rubbers, putting an end to this residue generated in the cellulose industry and providing vulcanized rubbers with similar or enhanced properties in relation to those already known. The process for treating dregs includes the steps of: (a) drying the dregs; and (b) micronization of the dry dregs to an average particle size (d50) from 2 to 45 micrometers. Further provided herein are treated dregs, a use of treated dregs as vulcanization activator, and a process for vulcanizing rubber and the vulcanized rubber.