摘要:
There is disclosed a new process for preparing oxysulphides of yttrium, gadolinum or lanthanium doped with elements of the rare earth groups, that is to say oxysulphides of yttrium, gadolinum or lanthanium in which the base element is partially substituted by elements of the rare earths group and which, on excitation by ultraviolet radiations or by electrons, become luminescent and emit radiations in the visible spectrum. An aqueous suspension or solution of an oxide, nitrate or halide of yttrium, gadolinum or lanthanium, an oxide, nitrate or halide of a rare earth element, and a sulphurating element, is subjected to a hydrothermal synthesis, optionally in the presence of a base for adjusting the pH of the aqueous medium to a pH of from 8 to 12; the solid product of the hydrothermal synthesis is filtered and dried; the dried solid product is mixed with a sulphurizing compound, subjected to a heat-treatment, reduced to a pulp in water and filtered and dried to obtain the oxysulphide having the desired degree of luminescence.
摘要:
A polyolefin composition which is highly receptive to acid, metallized, and disperse dyes comprises a mixture of about 99 to 75 percent by weight of a polyolefin consisting essentially of isotactic macromolecules and about 1 to 25 percent by weight of a basic nitrogen-containing polyamide obtained from the amination of homopolymers and copolymers of esters of alpha, betaunsaturated acids. The preparation of fibers and shaped articles from this composition is also disclosed.
摘要:
Substantially linear, amorphous, unsaturated, high molecular weight copolymers of at least one monoolefin selected from ethylene and higher alpha-olefins, with 1, 4, 9-decatriene, alkyl, aryl, and arylalkyl-substituted 1, 4, 9-decatrienes, or 1, 5, 9-decatriene, are disclosed. The copolymers are sulfurvulcanizable to useful synthetic eleastomers. A process for obtaining the copolymers by copolymerizing a mixture of the selected monomers in contact with catalysts prepared from certain transition metal compounds and organometallic compounds or hydrides of Group I to III metals is also disclosed.
摘要:
New and novel copolymerizates of ethylene and/or aliphatic alpha-olefins containing three to eight carbon atoms with nonconjugated diolefins containing at least one terminal unsaturation of vinyl type are disclosed. The copolymerizates are obtained by copolymerizing nonconjugated aliphatic diolefins containing at least one vinyl unsaturation and from five to 15 carbon atoms with ethylene or with ethylene and aliphatic alpha-olefins containing three to eight carbon atoms in the liquid phase but in the absence of halogenated aliphatic hydrocarbons, with a catalyst prepared from particular vanadium compounds and alkyl aluminum halides, both the preparation of the catalyst and the copolymerization being carried out a temperature between -80*C and +10*C.
摘要:
A thermoplastic film for controlling plant growth which has a total light transmittance to sunlight of less than 40% for light with a wavelength of 300 - 700 m Mu and a light transmittance greater than 60% for wavelengths above about 900 m Mu and preferably between 90 and 1,500 m Mu . The foil or film thickness may be 0.01 to 0.5 mm and the light transmittance characteristics thereof correspond to the following table:
摘要:
1. A PROCESS FOR THE ANIONIC POLYMERIZATION OF PYRROLIDONE TO A FIBER-FORMING POLYPYRROLIDONE WHICH COMPRISES POLYMERIZING SAID MONOMER IN CONTACT WITH A CATALYTIC SYSTEM CONSISTING ESSENTIALLY OF AN ALKALI METAL OR QUATERNARY AMMONIUM PYRROLIDONATE AND, AS ACTIVATOR, A SUBSTITUTED OLEFIN HAVING THE GENERAL FORMULA
摘要:
THERE IS DISCLOSED A PROCESS FOR PRODUCING COPOLYMERS OF VINYL CHLORIDE WITH ACRYLIC ACID ESTERS WHICH COMPRISES POLYMERIZING A MIXTURE OF VINYL CHLORIDE, CARBON MONOXIDE AND A COMPOUND CONTAINING ALCOHOLIC FUNCTIONS IN CONTACT WITH AN INITIATOR OR CATALYST OF THE RADICALIC TYPE. SUCH AS A PEROXIDE, AZO-COMPOUND, REDOX SYSTEM, OR THE LIKE.
摘要:
IN SOLUTION IN AN ORGANIC SOLVENT, WITH TERT. BUTYL HYPOCHLORITE AND WITH AQUEOUS NITRIC ACID IN A CONCENTRATION NOT HIGHER THAN 85%.
in which R and R'' are Cl or -O-NO2, R and R'' being different. A method for preparing the new polyalkenamer chloro-nitroesters is also disclosed and comprises reacting a polymer the macromolecules of which consist essentially of one or more repeating units -CH CH - (CH2-)n and/or
in which n is a whole number from 2 to 10, and/or formula II:
New soluble substituted polyakenamers are disclosed, the macromolecules of which consist, predominantly or essentially, of one or more repeating units which are the same or different and which have formula I:
摘要:
ALCOLHOLS ARE DIRECTLY SYNTHESIZED FROM OLEFINS BY OXOREACTION IN A PROCESS COMPRISING A HYDROFORMYLATION PHASE AND A HYDROGENATION PHASE IN WHICH BOTH PHASES PROCEED IN THE PRESENCE OF AN OXO-REACTION CATALYST, MORE PARTICULARLY COBALT CARBONYLS OR CARBONYLABLE COBALT SALTS, AND THE HYDROGENATION PHASE IS CARRIED OUT IN THE PRESENCE OF FROM 5% TO 15% BY VOLUME OF WATER, BASED ON THE VOLUME OF THE OLEFIN, AND, OPTIONALLY, IN THE PRESENCE OF AN ORGANIC ACID.
摘要:
A NEW CLASS OF POLYMER COMPRISING A MAIN CARBON CHAIN AND HAVING POLYFLUOROPOLYETHER SIDE GROUPS. THE POLYMERS POSSESS EXCELLENT SOIL AND WATER RESISTANT PROPERTIES AND ARE USEFUL FOR RENDERING FABRICS SOIL AND MOISTURE RESISTANT. THE POLYMERS ARE PREPARED FROM A NEW CLASS OF POLYMERIZABLE POLYFLUORINATED POLYMER ACRYLATES, METHACRYLATES, ACRYLAMIDES AND METHACRYLAMIDES. A NEW CLASS OF ALCOHOLS, USEFUL FOR PREPARING THE ACRYLATE AND METHACRYLATE MONOMERS IS DISCLOSED AND METHODS FOR PREPARING THE ALCOHOLS, MONOMERS AND POLYMERS ARE DISCLOSED.