Abstract: A method of forming a porous mullite composition of acicular mullite grains having improved properties is described, where the mullite is formed at some time in the presence of a fluorine containing gas. For example, it has been discovered that improved properties may result from heating the mullite to a high temperature in an atmosphere selected from the group consisting of water vapor, oxygen, an inert gas or mixtures thereof or forming the mullite composition from precursors having an Al/Si ratio of at most 2.95.

Abstract: An improved energy absorbing member comprising, an thermoplastic cellular polymer in contact with a structural element such as a metal guard rail or automotive door, wherein the cellular polymer has an average cell size of at least about 0.75 mm and at least one of CE/CT, CV/CT and CH/CT is about 0.25 to about 0.4 said one of CE/CT, CV/CT and CH/CT having a compressive efficiency of at least 70% at a 60% strain, CE, CV and CH being the compressive strength of the cellular polymer in each of three orthogonal directions E, V and H where one of these directions is the direction of maximum compressive strength in the foam and CT equals the sum of CE, CV and CH.

Abstract: The present invention relates to a two-component epoxy adhesive composition comprising a) a first component comprising a first epoxy resin and a second epoxy resin, the second epoxy resin being flexibilized by an elastomer, and b) a second component comprising at least one amine compound with one or more primary and/or secondary amino groups, said amine compound having a molecular weight of less than 450 g/mol. The ratio of the total number of amino groups of the amine compound to the total number of epoxy groups of the epoxy resins is 0.01:1 to 0.5:1. The mixing of the two components a) and b) results in a wash-off resistant composition. Said wash-off resistant composition results upon heat-curing in a crash-stable structural adhesive.

Abstract: A mullite composition is comprised substantially of mullite grains that are essentially chemically bound wherein the composition has at least two adjoining regions that have substantially different microstructures. The composition may be produced by forming a mixture of one or more precursor compounds having the elements present in mullite; shaping the mixture into a porous green shape applying a nucleation control agent to a portion of the porous green shape and then heating the porous green shape under an atmosphere and to a temperature sufficient to form the mullite composition.

Abstract: A high char yield polybenzoxazine is formed by mixing (i) a benzoxazine compound, (ii) a furan compound, (iii) a benzoxazine-furan compound or combinations thereof, wherein the mixture has a benzoxazine ring to furan ring ratio from about 0.001 to about 10 and then heating the mixture for a sufficient time to form the polybenzoxazine.

Abstract: A ceramic-metal composite that is tough and stiff has been prepared and is comprised of an inert ceramic (e.g., alumina) embedded and dispersed in a matrix comprised of a metal (e.g., aluminum), a reactive ceramic (e.g., boron carbide) and a reactive ceramic-metal reaction product (e.g., AlB2, Al4BC, Al3B48C2, AlB12, Al4C3, AlB24C4 or mixtures thereof) wherein grains of the inert ceramic have an average grain size greater than or equal to the average grain size of grains of the reactive ceramic. The ceramic-metal composite may be prepared by forming a mixture comprised of an inert ceramic powder (e.g., alumina) and a reactive ceramic powder (e.g., boron carbide), the inert ceramic powder having an average particle size equal to or greater than the average particle size of the reactive ceramic powder, forming the mixture into a porous body and consolidating the porous body in the presence of a metal (e.g., aluminum) to form the ceramic-metal composite.

Abstract: A filler powder comprised of an alumina powder coated with a silicon containing coating, wherein the silicon containing coating at most partially covers the surface of said coated alumina powder and the filler powder, when mixed with a thermosetting epoxy resin, has an average spiral flow length that is at least about 1.1 times greater than a comparable filler powder containing uncoated alumina powder mixed with the thermosetting resin. A preferred process for making the filler powder comprises: heating, simultaneously, an alumina powder with a second powder coated with an organo-silicate to a temperature for a time sufficient to volatilize, deposit and pyrolyze at least a portion of the organo-silicate on the alumina powder to form a silicon containing inorganic coating thereon.

Abstract: A water-borne epoxy resin coating composition comprised of: (a) particles of an epoxy resin having a neutral or positive surface charge dispersed in (b) water, an amount of (c) surfactant sufficient to disperse the epoxy resin in the water, the surfactant being a nonionic surfactant, amphoteric surfactant or mixture thereof and (d) a latent curing agent, may be applied to a metal substrate absent a primer coating and, subsequently, heated to form a cured coating on the substrate. The latent curing agent is (i) at least partially dissolved in the water, (ii) essentially insoluble with the epoxy resin and (iii) present in a sufficient amount to cure the epoxy resin. An example of a suitable latent curing agent is dicyandiamide. The cured coating displays excellent adherence, wear resistance and resistance to solvents such as acetone, a 1N HCl solution and a 1N KOH solution.

Abstract: An aluminum-boron-carbon abrasive article is comprised of at least three phases selected from the group consisting of: B.sub.4 C; AlB.sub.2 ; AlB.sub.12 ; AlB.sub.12 C.sub.2 ; Al.sub.4 C.sub.3 ; AlB.sub.24,C.sub.4 ; Al.sub.4 B.sub.1-3 C.sub.4 ; AlB.sub.24 C.sub.4 and Al.sub.4 BC. At least a portion of the surface of the abrasive article is comprised of abrasive grains of at least one phase selected from the group consisting of AlB.sub.24 C.sub.4, Al.sub.4 BC and AlB.sub.2, where the abrasive grains have an average grain size that is at least about two times greater than the average grain size of the grains containing boron and carbon within the abrasive article. The aluminum-boron-carbon abrasive article of claim 1 is prepared by heating, under a vacuum or inert atmosphere, a body comprised of at least one boron containing phase and at least one carbon containing phase in the presence of a separate source of aluminum, such as aluminum metal or alloy thereof.

Abstract: A polyisocyanate prepolymer composition is comprised of the reaction product of (a) a polyisocyanate having an average functionality of at least 2 and containing at least about 20 percent by weight of a diisocyanate monomer, (b) a monohydric alcohol and (c) a polyol having an average hydroxyl functionality of at least about 1.8 to at most about 3.2, wherein the prepolymer composition has (i) an amount of isocyanate groups by weight sufficient to react with water in the absence of a supplemental blowing agent to make a foam, (ii) at most about 10.0 percent by weight of the diisocyanate monomer and (iii) an amount of the polyisocyanate that is capped by the monohydric alcohol sufficient to prevent gelling of the prepolymer composition. The prepolymer composition may be formed by contacting (i) an organic polyisocyanate having an average isocyanate functionality of at least about 2.

Abstract: A braking component such as a brake pad, brake rotor, brake drum or clutch disk is comprised of a metal substrate having a friction material laminated on at least a portion of at least one face of the metal substrate, the friction material being a ceramic-metal composite comprised of a metal phase and a ceramic phase dispersed within each other, wherein the ceramic phase is present in an amount of at least about 20% by volume of the ceramic-metal composite. In particular, the braking component is a metal substrate, such as aluminum, having laminated thereto a ceramic-metal composite of a dense boron carbide-aluminum composite having high specific heat and low density.

Abstract: A hard drive disk substrate is formed of a multi-phase ceramic-based material having at least two phases with amorphous phases being present in an amount less than about 1 volume percent based on the volume of the ceramic-based material or at least one phase being free metal. A process for producing the ceramic-based disk substrate is produced by forming a flat disk of a porous ceramic and then infiltrating the porous ceramic with a metal whereby a multi-phase ceramic-based computer hard drive disk is produced. Additionally, a step of passivating the porous ceramic by elevating it to a temperature of about 1300.degree. to about 1800.degree. C. before the infiltrating step may be performed, such that the surfaces are passivated and the reaction kinetics can be controlled during the infiltrating step. A preferred composite material is made of a multi-phase boron carbide composite material including grains having peaks with an average roughness value, Ra, of between about 1 to about 200.ANG.

Abstract: A submicrometer transition metal carbonitride is produced having the formula:M.sub.a M'.sub.b M".sub.(1-a-b) (C.sub.1-x) N.sub.x).sub.zwherein M is Ti, Zr or Hf; M' is V, Nb or Ta; M" is Cr, Mo or W; a ranges from 0 to 1; b ranges from 0 to 1 with the proviso that (a +b) is less than or equal to 1; x ranges from about 0.02 to about 0.95 and z ranges from about 0.9 to about 2. The transition metal carbonitride is produced by mixing (a) a transition metal oxide source of a transition metal in the above formula and (b) a carbon source such as carbon black.

Abstract: A transition metal carbide-Group VIII metal powder comprising discrete particles of a transition metal carbide and Group VIII metal wherein: substantially all of the particles have a size of at most 0.4 micrometer; the transition metal carbide is selected from carbides of the group consisting of tungsten, titanium, tantalum, molybdenum, zirconium, hafnium, vanadium, niobium, chromium, mixtures and solid solutions thereof; and the Group VIII metal is selected from the group consisting of iron, cobalt, nickel, mixtures and solid solutions thereof. Said powders are produced by heating an admixture comprising a finishing source of carbon (e.g., acetylene black), a source of a group VIII metal (e.g., Co.sub.3 O.sub.

Abstract: Polyimide precursor solutions comprise an organic liquid and the reaction product of an aromatic dianhydride and an aromatic diaminobenzoxazole capped, on at least one terminal end, with a bifunctional chain extender. The bifunctional chain extender has one functional group reactive with the amine of the aromatic diaminobenzoxazole or the anhydride of the aromatic dianhydride and another functional group which does not form amic acid linkages, but which is capable of further reaction to increase the molecular weight of the polyimide precursor under conditions other than those used to react the aromatic diamine and aromatic dianhydride to form the polyimide precursor. These polyimide precursors can be converted into polyimidebenzoxazole polymers.

Abstract: A polymer polyol is produced by a process comprising free radical polymerizing an addition polymerizable di-(substituted phenyl)monomer (e.g., methacrylic ester of diglycidylether of tetrabromobisphenol A) component in the presence of a polyol, wherein the monomer has at least one aromatic halogen and at least one aromatic ethylenically unsaturated substituent. The polymer polyol can also be made by copolymerizing said monomer with an additional ethylenically unsaturated monomer component such as styrene and acrylonitrile. Said polymer polyols are reacted with a polyisocyanate compound forming a flame retardant polyurethane foam.