Abstract: A method for making an essentially unsaturated synthetic meixnerite with high CO.sub.2 adsorption abilities. The method comprises activating hydrotalcite, then cooling and rehydrating such activated material in a carbon dioxide-free environment. The resultant material can absorb more than 10 milliliters of CO.sub.2 per gram.

Abstract: There is provided a method for making a monovalent inorganic anion-intercalated hydrotalcite-like material by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free, aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a monovalent inorganic anion, in its acid or soluble salt form, to make a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a bromide-, chloride-, nitrate- or vanadate-intercalated, hydrotalcite-like material.

Abstract: A method for making a synthetic mixed metal oxide or meixnerite which, when activated, has a high B.E.T. surface area, typically about 290 m.sup.2 /g or greater. The method comprises activating hydrotalcite, then cooling and hydrating such activated material with a metal salt solution in a carbon dioxide-free environment. Such hydration can produce a material that absorbs more than 100% of its weight in water. Following hydration, this material is activated a second time in a virtually carbon dioxide-free environment. Such reactivation decomposes the salt and leaves a supported metal oxide readily available to be used for catalyst reactions.

Abstract: There is provided a method for making a polyvalent inorganic anion-intercalated hydrotalcite-like material by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free, aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a polyvalent inorganic anion, in its acid, acid salt or ammonium salt form, to make a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a borate- metatungstate- and paramolybdate-intercalated hydrotalcite-like material.

Abstract: There is provided a method for making monovalent organic anion-intercalated hydrotalcite-like materials by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free, aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a monovalent organic anion to form a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a stearate-, acetate- or benzoate-intercalated hydrotalcite-like material.

Abstract: There is provided an improved method for making synthetic hydrotalcite by first reacting a divalent metal compound with a trivalent metal oxide powder in a carboxylic acid-free, aqueous solution or suspension to form an intermediate. This intermediate is then contacted with an anion source such as carbon dioxide; a carbonate-containing compound; an acid or an ammonium salt to form a layered double hydroxide having the formula:A.sub.1-x B.sub.x (OH).sub.2 C.sub.z.mH.sub.2 O, where A represents a divalent metal cation, B represents a trivalent metal cation, C represents a mono- to polyvalent anion, and x, z and m satisfy the following conditions: 0.09<x<0.67; z=x/n, where n=the charge on the anion; and 2>m>0.5. Said layered double hydroxide is typically separated from the suspension by filtering, centrifugation, vacuum dehydration or other known means.

Abstract: There is provided an improved method for making synthetic hydrotalcite by first reacting powdered magnesium oxide with a high surface area, transition alumina in a solution or suspension to form a meixnerite-like intermediate. This intermediate is then contacted with an anion source such as an acid, and most preferably carbon dioxide, to form the layered double hydroxide which is separated from the suspension by filtering, centrifugation, vacuum dehydration or other known means. On a preferred basis, the transition alumina combined with activated magnesia consists essentially of an rehydratable alumina powder having a surface area of 100 m.sup.2 /g or greater. To make related double hydroxide compounds, still other reactants such as bromides, chlorides, boric acids, or salts thereof, may be substituted for the carbon dioxide gas fed into this suspension.

Abstract: There is provided a method for making a divalent inorganic anion-intercalated hydrotalcite-like material by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a divalent inorganic anion, in its acid, acid salt or ammonium salt form, to make a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a sulfate- and metavanadate-intercalated hydrotalcite-like material.

Abstract: There is provided a method for making a divalent or polyvalent organic anion-intercalated hydrotalcite-like materials by first reacting a magnesium-containing powder and a transition alumina powder in an aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a dicarboxylate or polycarboxylate anion to form a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include an oxalate-, succinate- or terephthalate-intercalated hydrotalcite-like material.

Abstract: A method of reducing the agglomeration of inorganic powdered material, the method comprising: (a) providing an inorganic powdered material comprising ceramic particles; (b) coating the ceramic particles with a solution containing from 0.05-0.5 wt. % of a polysiloxanol oligomer of a trialkoxysiloxane monomer having the structure Si(OR').sub.3 wherein R' represents a C.sub.1 -C.sub.4 alkoxy group selected from the group consisting of methyl, ethyl, isopropyl and n-butyl and wherein the oligomer has chains having a number average distribution with a number average degree of polymerization X.sub.n in the range above 2 but below the gel point; and (c) drying the inorganic powdered material.

Abstract: A composition is provided which comprises a 3,9-bis (2,4,6-tri-t-alkylphenoxy)-2,4,8,10-tetroxa-3,9-diphosphaspiro[5.5]undecan e, and polymer compositions are provided which include a polymer and an effective amount of one or more 3,9-bis(2,4,6-tri-t-alkylphenoxy)-2,4,8,10-tetroxa-3,9-diphosphaspiro[5.5] undecane.

Abstract: Poly(alkylene terephthalate) compositions containing a stabilizing proportion of a pentaerythritol diphosphite ester. The compositions are relatively stable under usual processing conditions which include high temperatures. Color formation, molecular degradation and acetaldehyde contamination are inhibited significantly.

Abstract: A protective dental film formed by exposing surfaces of the oral cavity to a preparation capable of coacting with saliva to produce one or more tenacious and continuous barrier layers upon tooth and tissue surfaces.

Abstract: Flame-retardant polycarbonate compositions containing a pentaerythritol diphosphonate or diphosphate. A halogenated organic compound having at least about 30% halogen may also be present.