摘要:
A polyurea elastomer is disclosed. The elastomer includes an isocyanate, an amine terminated polyoxyalkylene polyol, and a chain extender. The isocyanate is preferably a quasi-prepolymer of an isocyanate and a material selected from at least one polyol, a high molecular weight polyoxyalkyleneamine or a combination thereof. The chain extender includes at least an alkyl substituted piperazine.
摘要:
Polyamide reaction products comprising: a dicarboxylic acid and a diamine component comprising a mixture of poly(oxytetramethylene) diamines and oligomers of said poly(oxytetramethylene) diamines,said mixture containing from about 85 to about 99.5 wt. % of said poly(oxytetramethylene) diamines and, correspondingly, from about 15 to about 0.5 wt. % of said oligomers,said poly(oxytetramethylene) diamines having the formula: ##STR1## wherein n represents 0 or a positive number having a value of 1 to about 30,said oligomers having the formula: ##STR2## wherein n represents 0 or a positive number having a value of 1 to about 30.
摘要:
A method is disclosed for the improved production of N-methylpyrrolidine at moderate conditions which comprises the steps of reacting N-methylpyrrolidone with hydrogen over a copper chromite catalyst at a moderate temperature and a pressure of 1000 psig to 5000 psig and thereafter isolating the N-methylpyrrolidine by extraction with an aliphatic hydrocarbon solvent having a boiling point less than 70.degree. C. or greater than 90.degree. C.
摘要:
Macrocyclic oxamides may be made easily, in good yield and in one step by reacting an oxalic compound, such as oxalic acid or oxalic esters, with a diamine, where the amine groups are separated by at least five atoms. The oxalic compounds may include, but are not limited to such materials as dimethyl oxalate and diethyl oxalate. The diamines may include, but are not limited to such materials as alkylenediamines; polyalkylene glycol diamines; alkyl-bis-(aminoalkyl)amines; imino bis-(alkyl)amines; and N,N' bis-(aminoalkyl)-N,N'-dialkylalkylenediamines and bis-(aminoalkyl)piperazines; and mixtures thereof. The macrocyclic oxamides made by this process may be used to selectively separate metal ions from solution, or complexed together with a metal ion act as a catalyst.
摘要:
Disclosed is an improvement in a process for production of cyclohexane by liquid phase hydrogenation of benzene wherein no diluent is necessary, which comprises contacting benzene and hydrogen in the presence of a mixed catalyst bed comprising a first catalyst which is a less active hydrogenation catalyst selected from elements of Group VIII of the Periodic Table and a second, more active catalyst, comprising a Group VIII metal supported on an oxide, such as, for example, alumina, silica or titania at a temperature of about 40.degree. C. to about 300.degree. C. and pressure sufficient to keep the benzene liquid at the chosen reaction temperature.
摘要:
Disclosed is a two-step method for the preparation of cyclic urea products which comprises: heating a diamine with urea in a mole ratio of about 1 at a temperature from about 120.degree. C. to 140.degree. C. until a mole of ammonia is liberated and slowly heating the intermediate with an alcohol or polyether solvent to a temperature from about 160.degree. C. to 200.degree. C. to produce the cyclic urea products.
摘要:
Disclosed is a process wherein cyanoethylation is accomplished by reacting a compound of the formula: ##STR1## where R=H or CH.sub.3, n=1 to 3 and m=0 to 50, and acrylonitrile over a heterogeneous catalyst comprising, potassium fluoride or cesium fluoride supported on an oxide of an element from the group consisting of Group IA, IIA or IIIA of the Periodic Table.
摘要:
Disclosed is a method for preparing aliphatic polyureas in varying reaction times which comprises reacting polyoxyalkylene polyamines, an aliphatic diisocyanate and a sym-dialkylethylenediamine.
摘要:
Disclosed is a method for selective formation of amidoamines which comprises reacting a carboxylic acid group, such as, for example, a diacid or an aliphatic acid terminated amide with an aminopropylated disecondary amine which contains a secondary amine terminus in the same molecule at a temperature of about 150.degree. C. to about 260.degree.0 C.
摘要:
A polyurea elastomer is disclosed. The elastomer includes an isocyanate, an amine terminated polyoxyalkylene polyol, and a chain extender. The isocyanate is preferably a quasi-prepolymer of an isocyanate and a material selected from at least one polyol, a high molecular weight polyoxyalkyleneamine or a combination thereof. The chain extender includes a minor amount of a tetraalkylpiperazine and a major amount of diethyltoluenediamine. A one-step method of making the tetraalkylpiperazine and tetraalkylpiperazinone is also disclosed. The method includes reacting a 2-amino-2-alkyl-1-alkanol in the presence of a nickel-iron-copper-manganese catalyst.