A hollow spherical glass particle, comprising aluminum oxide Al.sub.2O.sub.3, silicon dioxide SiO.sub.2 and at least one metal oxide, wherein the metal oxide is selected from the group consisting of alkali metal oxides and alkaline earth metal oxides, wherein the ratio of aluminum atoms to alkali metal atoms is about 1:1 and the ratio of aluminum atoms to earth alkali atoms is about 2:1, with the proviso that the hollow spherical glass particle is free of boron.

The present disclosure concerns expandable silica particles having a coating comprising talc powder and kaolin powder provided on the outer surface of the expandable silica particle and expandable and expanded silica particles comprising silica fume and/or ultrafine quartz silica sand beneath the surface of the particles. Methods for producing expandable and expanded silica particles are disclosed, including a method using a vibration plate and a furnace having a vibration plate for carrying out that method. The expanded silica particles have high compressive strength, substantially uniform cell size and distribution, low water absorption, and low porosity on the outer surface. They are useful as a filler in matrix materials, like concrete or epoxy, as insulation material with various binder materials, and as water filtration medium.

Coated proppants which exhibit superior proppant coatings and less fines generation are prepared by coating proppant particles with a reactive hybrid resin prepared by reaction of a phenol-formaldehyde resin and a co-reactive organopolysiloxane having at least three repeating siloxy groups, and is in free flowing form.

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.2CFRf, 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.

A glass bubble includes a hollow glass body having an outer surface with a diameter of between about 16 micrometers and about 25 micrometers and a surface roughness of about 0.01% to about 0.1% of that diameter. A low density sheet molding compound incorporating a plurality of glass bubbles and resin is also disclosed.

A porous glass base material manufacturing system that does not require the manufacturing apparatus and building to be hazardous material-compatible and that can provide a stable supply of raw materials, even when organic siloxane raw material is used as raw materials to produce silica fine particles includes a raw material supplying apparatus and a porous glass base material manufacturing apparatus. The raw material supplying apparatus includes: a raw material tank in which organic siloxane raw material in a liquid state is stored and the remaining space is filled with inert gas; a liquid feed pump to pump the organic siloxane raw material from the raw material tank; a circulating piping and a branch piping through which the raw material pumped is passed; a liquid mass flow controller that controls the flow rate of organic siloxane raw material passed through the branch piping to a predetermined flow rate; and a vaporizer.

A method for producing hollow glass microspheres includes preparing an aqueous suspension of starting materials including finely ground glass and waterglass. Combustible particles are produced from the suspension and are mixed with an AlO(OH)-containing pulverulent release agent. The mixture of combustible particles and release agent is introduced into a combustion chamber of a furnace where it is expanded at a combustion temperature which exceeds the softening temperature of the finely ground glass, to form the hollow microspheres. Hollow glass microspheres produced according to the method are also provided.

Hollow glass microspheres are produced. An aqueous suspension is prepared of starting materials of finely ground glass and waterglass. Firing material particles are produced from the suspension and are mixed with a pulverulent release agent. The mixture of firing material particles and release agent is introduced into a firing chamber of a furnace where it is expanded at a firing temperature which exceeds the softening temperature of the finely ground glass, to form the hollow microspheres. The release agent is Al(OH).sub.3 and dehydroxylated kaolin.

Compositions and methods for glass composites suitable for tissue augmentation, biomedical, and cosmetic applications are provided. The glass microsphere component of the composites are biologically inert, non-reactive and act as a nearly permanent tissue filler. One embodiment provides a tissue augmentation composite containing an effective amount of solid glass microspheres, hollow glass microspheres, porous wall hollow glass microspheres, or combinations thereof with a suitable biocompatible matrix to serve as a bulking agent when injected into a patient. The compositions can be used for soft or hard tissue augmentation as well as delivery of cargos on demand.

A multi-layer thermal barrier may be applied to a surface of components within an internal combustion engine. The multi-layer thermal barrier provides low thermal conductivity and low heat capacity insulation that is sealed against combustion gasses. The multi-layer thermal barrier includes two, three, or more layers, bonded to one another, e.g., a first (bonding) layer, a second (insulating) layer, and a third (sealing) layer. The insulating layer is disposed between the bonding layer and the sealing layer. The bonding layer is bonded to the component. The insulating layer includes hollow microstructures that may be sintered together to form insulation that provides a low effective thermal conductivity and low effective heat capacity. The sealing layer may be formed of a ceramic material, and the insulating layer may include deformed microstructures having a greater width than height.