摘要:
Blends of diaminoisopropylbenzene (DAIBP) and diaminoethylbenzene (DAEB) are provided for curing epoxy resins. The cured epoxy resins have increased tensile strength and slightly lower glass transition temperatures as compared with resins cured with either diamine alone.
摘要:
Blends of diaminoisopropylbenzene (DAIPB) and diaminoethylbenzene (DAEB) are provided for curing epoxy resins. The cured epoxy resins have increased tensile strength and slightly lower glass transistion temperatures as compared with resins cured with either diamine alone.
摘要:
Method of promoting the cure of unsaturated polyester resins with a peroxide initiator at room or below room temperatures (low temperatures) by including as a promoter N,N-dimethyl-p-toluidine (DMPT) or a blend of DMPT and N,N-dimethyl-m-toluidine (DMMT) and to the polyester composition containing such promoter. The use of the DMPT or blend of DMPT and DMMT as a promoter provides a fast cure at low temperatures without loss of physical properties of the cured resins.
摘要:
The selective ring-alkylation of anilines comprising providing a mixture of a lower alkanol and an aniline, exposing said mixture to a temperature of from 300.degree. C. to 500.degree. C., preferably from 350.degree. C. to 450.degree. C., in the presence of an acidic Y-type zeolite is described. The Y-type zeolites are predominantly selective to the formation of para-alkylanilines.
摘要:
A two-stage process for the co-production of aniline and m-phenylenediamine where, in the first stage, benzene, nitric acid, and sulfuric acid are reacted in a liquid phase to produce in greater amounts nitrobenzene (approximately 70%) and m-dinitrobenzene (approximately 30%), and in lesser or trace amounts o-dinitrobenzene and p-dinitrobenzene, and water; and in the second stage the products of the first stage are reacted with hydrogen in the liquid phase to produce aniline (approximately 70%) and m-phenylenediamine (approximately 30%) in greater amounts, and o-phenylenediamine and p-phenylenediamine in lesser amounts, and water. The reaction products are separated by distillation. The first stage of a preferred embodiment of the process is characterized in that a concentrated mixture of nitric acid and sulfuric acid are fed along with mononitrobenzene to a first reactor for producing dinitrobenzene, and then the dilute acid mixture recovered from this first reactor is fed along with benzene to a second reactor for producing the mononitrobenzene used as a reactant in the first reactor. The second stage, which provides the aniline and m-phenylenediamine, is characterized in that the hydrogenation is carried out in the liquid phase with the unpurified reaction products from the first stage.Preferably, the second stage reaction is carried out utilizing a palladium-on-carbon catalyst in an amount of from 0.006 to 0.25 wt. % based on the total weight of the first stage reaction product mixture. The process is applicable to the co-production of other aromatic mono- and diamines.
摘要:
A process of selectively recovering a nitrophenolic by-product, namely 2,4-dinitrophenol and picric acid, from nitration waste water in substantially pure form through the control of the solution pH of the nitration waste water and subsequent precipitation is provided. By adjusting the solution pH of the nitration waste water with an acid to a pH in the range of from about 4.0 to 0.5, the solubility of the selected nitrophenolic by-products is affected and the crystal formation of the individual by-products controlled.
摘要:
Disclosed is a method for the preparation of salts of N-phosphonomethylglycine which comprises the steps of (a) reacting hydantoin or a 3-substituted hydantoin, a compound of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, alkyl having from 1 to 10 carbon atoms, aryl having from 6 to 12 carbon atoms, alkylcarbonyl wherein the alkyl group has from 1 to 10 carbon atoms, and arylcarbonyl wherein the aryl group has from 6 to 12 carbon atoms, with paraformaldehyde in the presence of a low molecular weight carboxylic acid at a temperature and for a sufficient period of time to produce a mixture of intermediate products, including the 1-hydroxymethyl derivative of the starting hydantoin; (b) converting said 1-hydroxymethyl derivative to the 1-phosphonomethyl derivative by thereafter adding to the reaction mixture either (i) a substituted phosphorus compound selected from the group consisting of phosphorus trichloride, and phosphorus tribromide; or (ii) adding to the reaction mixture phosphorous acid and a anhydride selected from the group consisting acetic anhydride, propionic anhydride, butyric anhydride, or mixture thereof, and continuing said reaction at a temperature and for a sufficient period of time to cause completion of the reaction to form the 1-phosphonomethyl derivative; and (c) hydrolyzing the 1-phosphonomethylhydantoin product thus formed with a base selected from the group consisting of alkali metal or alkaline earth hydroxide, to produce a salt of N-phosphonomethylglycine.
摘要:
A process for selectively recovering a nitrophenolic by-product from nitration waste water in substantially pure form by solvent extraction is provided. The pH of the waste water is adjusted using an acid to affect the solubility of a particular nitrophenolic by-product in the waste water so that the by-product is selectively separable from the other components of the nitration waste water by solvent extraction.
摘要:
The selective N-alkylation of anilines comprising providing a mixture of a lower alkanol and an aniline, exposing said mixture to a temperature of from 250.degree. C. to 350.degree. C. in the presence of an acidic zeolite having a pore size of from 6 to 8 angstroms with a three-dimensional tubular shape, such as S-115 zeolite, is described. These zeolites are predominantly selective to the formation of N-alkylanilines.
摘要:
Arylphosphinic acids are prepared by reacting an aromatic compound with phosphorus trichloride in the presence of aluminum chloride to form an aluminum/phosphorus complex and then hydrolyzing the complex with aqueous phosphoric acid to form the arylphosphinic acid as an insoluble phase and a soluble aluminum salt. The arylphosphinic acid and aluminum salt are then easily separated.