Abstract: Aqueous alumina coating compositions well adopted for directly impregnating/coating both ceramic and metallic catalyst supports to provide integral, both macroporous and microporous coatings therefor, which coated supports are useful for the fabrication of a wide variety of catalysts for catalyzing a broad spectrum of reactions, including those characterized by highly limited internal diffusion or by progressive catalyst poisoning, e.g.
Abstract: Microorganism-resistant, storage-stable, single-component room temperature vulcanizable organopolysiloxane compositions, especially adapted as sealants, are comprised of:(A) 100 parts of an .alpha.,.omega.-dihydroxydiorganopolysiloxane polymer;(B) 2 to 25 parts of an organosilane;(C) 5 to 200 parts of inorganic filler material;(D) 0.0003 to 15 parts of a hardening catalyst; and(E) 0.01 to 1.2% by weight, based upon the total weight of the composition, of at least one fungicidal tetraalkylthiuram disulfide.
Abstract: Aqueous cationic dispersions of synthetic polymers obtained by reacting at least one unsaturated tertiary nitrogen compound not capable of being hydrolyzed in an acid or alkaline medium with an aqueous emulsion reaction mixture, containing cationic species, of at least one non-ionic monomer capable of being copolymerized with the nitrogen compound to form synthetic polymers and at least one substance which generates cationic species capable of chemically binding with the said synthetic polymers.
Abstract: Molding compositions for the fabrication of shaped articles having enhanced mechanical properties are comprised of (i) a polymeric matrix, (ii) an inorganic reinforcing filler material therefor, and, advantageously, (iii) a polymer/filler coupling agent, said reinforcing filler material consisting essentially of intimate admixture of enstatite and silica advantageously prepared by calcination of a precursor clay at a temperature of at least 800.degree. C.
Abstract: Stable amphoteric latices based on conjugated dienes formed by preparing an amphoteric aqueous dispersion of particles by reacting at least one unsaturated nitrogen compound capable of being hydrolyzed in an acid or alkaline medium with an aqueous emulsion reaction medium, containing cationic species, and polymerizing, in the aqueous dispersion, without prior neutralization of the dispersion, at least one conjugated diene or a mixture of conjugated dienes and at least one non-ionic monomer in the presence of an initiator selected from the group consisting of an uncharged initiator and a cationic-charge-generating initiator.
Abstract: Provided are single component organopolysiloxane compositions which are hardenable at ambient temperatures and contain as the cross-linking agent silanes with hydrocarbonoyloxy (acyloxy) or ketoniminoxy groups. The compositions further comprise a cross-linking catalyst which is an organic derivative of titanium, e.g., a titanium ester, polytitanoxane, alkanolamine titanate, etc., or an organic derivative of zirconium, e.g., a zirconate, polyzirconate, etc. After cross-linking, the present compositions provide organopolysiloxane elastomers exhibiting good properties.The organopolysiloxane compositions are referred to as "single component" to contrast them with the two-component organopolysiloxane compositions which are not storage stable and must therefore be handled in two separate packages, which problem is overcome by the present compositions.
Type:
Grant
Filed:
July 29, 1983
Date of Patent:
June 25, 1985
Assignee:
Rhone-Poulenc Specialites Chimiques
Inventors:
Bernard Laisney, Michel Letoffe, Patrice Perrin, Jean Ulrich
Abstract: Storage-stable, pumpable, concentrated polymer suspensions, well adapted for use as thickening and flocculating agents, are comprised of (i) a water-soluble polymer, (ii) at least one water-soluble surfactant, and (iii) water, the amount of water being less than about 30% by weight of the total weight thereof.
Abstract: Compositions of matter, desirably in powder form, adapted for ready dispersion/dissolution in an aqueous medium, and which rapidly provide maximum viscosity values therefor, are comprised of an intimate admixture of a water soluble biogum heteropolysaccharide, a dispersion/dissolution enhancing amount of a water donor material, and, advantageously, an anionic and/or nonionic surfactant.
Type:
Grant
Filed:
January 25, 1983
Date of Patent:
May 28, 1985
Assignee:
Rhone-Poulenc Specialites Chimiques
Inventors:
Jean-Bernard Chaux, Pierre Gagne, Michel Garcia, Dominique Lespinasse, Josiane Roussos
Abstract: Novel organopolysiloxane/polyurethane block copolymers which are thermoplastic elastomers and which possess good thermomechanical properties, are comprised of the following recurring units (A) and (B): ##STR1## wherein Z is a divalent radical which comprises a polysiloxane block and has the formula: ##STR2## in which Y and Y' are each a divalent radical having one of the formulae: ##STR3## wherein T and T' comprise the divalent or trivalent residue having from 1 to 20 carbon atoms of an unsaturated isocyanate or alcohol having one of the formulae:OCN--T--CR.sub.1 .dbd.CR.sub.2 R.sub.3HO--T--CR.sub.1 .dbd.CR.sub.2 R.sub.3 ##STR4## or an oxygen, sulfur, silicon, nitrogen, ester or amide interrupted such T or T' residue, and further wherein R.sub.1, R.sub.2 and R.sub.3 are each hydrogen, alkyl or aryl, with the proviso that two of the radicals R.sub.1 and R.sub.
Abstract: Thick-layer hybrid electronic printed circuits are formed by printing predetermined circuit pattern onto an insulating substrate by deposition of predetermined ink pattern thereupon, advantageously by silk-screening or masking, and then baking said ink circuit pattern, and repeating the deposition/baking steps as required, the subject forming process featuring use of an insulating ink comprising a non-conductive metallic oxide extender, desirably cuprous oxide, which ink is thus either potentially conductive or potentially resistive, and the development of such conductivity or resistivity, after baking, by treating the ink pattern with a reducing agent, desirably a borohydride, as to readily and quantitatively convert said metal oxide into a conducting metal.
Abstract: Spheroidal alumina particulates well adapted as catalysts or catalyst supports and having enhanced pore volumes are facilely prepared by drop coagulating an aqueous suspension or dispersion of alumina, or an aqueous solution of a basic aluminum salt, said suspension, dispersion or solution comprising an oil-in-water emulsion, and then recovering, drying and calcining the gelled particulates which result.
Abstract: Polysiloxanes of relatively low molecular weight are catalytically polymerized/rearranged into high molecular weight polysiloxanes in the presence of a cationic catalyst comprising a porous, inorganic mineral particulate support having an average pore diameter in excess of 20 .ANG. and a pore volume ranging from 0.2 to 2 ml/g, said porous support being coated with less than 15 mg/m.sup.2 of a film of polymeric material comprising pendant sulfonic or phosphonic acid functions, and said polymeric material being characterized by an ion exchange capacity of less than 2 milliequivalents per gram.
Abstract: Organopolysiloxane compositions which rapidly harden to the elastomeric state, even at ambient temperatures, are comprised of (i) a polyhydroxylated polysiloxane, (ii) a polyacyloxysilane cross-linking agent therefor, and (iii) a hardening accelerator comprising water and an alkali or alkaline earth metal phosphate and/or polyphosphate. The subject compositions are useful, inter alia, for providing elastomeric seals.
Type:
Grant
Filed:
January 25, 1984
Date of Patent:
April 2, 1985
Assignee:
Rhone-Poulenc Specialites Chimiques
Inventors:
Michel Letoffe, Roger Favre, Patrice Perrin
Abstract: An improved fluorinated siliceous catalyst, well adapted for the catalytic synthesis of aromatic/aliphatic nitriles from their corresponding formamides, formanilides or amides, is comprised of a plurality of silica particulates, the specific surface of which ranging from about 200 to about 300 m.sup.2 /g, having a total pore volume ranging from about 1 to about 1.5 cm.sup.3 /g, with an average pore diameter ranging from about 100 to about 200 .ANG., having an exchange pH of less than about 3, and with the fluorine content thereof bonded to the silica, expressed in F.sup.-, ranging from about 0.05 to about 2% by weight based upon the silica, and the sodium content thereof, expressed as Na.sub.2 O, being less than about 1% by weight, also based upon the silica.
Type:
Grant
Filed:
May 14, 1982
Date of Patent:
March 12, 1985
Assignee:
Rhone-Poulenc Specialites Chimiques
Inventors:
Roland Jacques, Michel Reppelin, Laurent Seigneurin
Abstract: Ultrapure and homogeneous boehmites and/or pseudo-boehmites, suitable, whether before or after drying and/or calcination, as, e.g., fillers, binders, thickeners, dispersing agents, and the like, are prepared (i) by admixing an amorphous aluminum hydroxycarbonate, itself advantageously prepared by carbonating an alkali metal aluminate with carbon dioxide and then filtering and washing the precipitate which results, with a solution of an acid, a base, a salt, or mixture thereof, with the pH of the resulting reaction medium being maintained at a value of less than 11, (ii) next heating such reaction medium at a temperature of less than 90.degree. C. for a period of at least 5 minutes, and (iii) then heating the reaction medium resulting from the step (ii) at a temperature ranging from 90.degree. C. to 250.degree. C.
Abstract: An organopolysiloxane composition is facilely photocured, e.g., into a variety of non-stick coatings, by subjecting to a photocross-linking amount of ultraviolet irradiation, admixture of (i) a polysiloxane comprised of hydroxysilyl groups devoid of Si-H bonds and containing no organic radicals which include sites of activated ethylenic unsaturation, and (ii) an aminopolyalkoxysilane.
Abstract: Industrial waste gases containing objectionable/polluting compounds of sulfur, e.g., H.sub.2 S, SO.sub.2 and such organosulfur derivatives as COS, CS.sub.2 and mercaptans, are catalytically desulfurized, e.g., by Claus process, employing an improved catalyst comprising titanium dioxide and calcium, barium, strontium or magnesium sulfate.
Abstract: Bromohalogenobenzenes are isomerized to useful, e.g., pharmaceutical or phytosanitary intermediates, by contacting the same with an alkaline base and a catalyst compound which forms a complex with the cation of said alkaline base.
Abstract: At least one of the other functions comprising an aryl-aliphatic ether, e.g., veratrol, is catalytically hydrolyzed with water, e.g., to guaiacol, in the presence of a catalytically effective amount of a salt of a carboxylic acid.
Abstract: The N-benzylimides having the structural formula: ##STR1## wherein Ar comprises a benzene radical and R.sub.1 is an aliphatic or aromatic hydrocarbon, are prepared in good yield by reacting a compound having the structural formula:ArH (II)with a compound having the structural formula: ##STR2## in the presence of hydrofluoric acid.