Patent GB-1090710-A (GB)
Title: Polyurethane elastomers
Inventor: ROSENDAHL FRIEDRICH-KARL
IPC: C08G18/10
Filed: 1965-12-08
Abstract: Segmented polyurethanes are prepared by reacting a substantially linear polyhydroxy compound with an excess of an organic diisocyanate to form a prepolymer containing free isocyanate groups, reacting this prepolymer in a polar solvent with an organic chain-lengthening agent containing reactive hydrogen atoms and a further chain-extending agent of the formula <FORM:1090710/C3/1> wherein A represents an amide, urethane, urea, acylsemicarbazide, acyl carbazinic ester, hydrazodicarbonamide or hydrazodicarboxylic ester amide group, R1 represents hydrogen, alkyl or an alkylsulphonate group, R2 and R3 represent an alkylene, cycloalkylene, arylene or aralkylene radical which may be interrupted by a hetero atom and/or closed to a ring and/or substituted by sulphorate groups and n represents 0 or an integer from 1 to 5, the amount of further chain-extending agent being 3 to 50 mols. per cent of the total quantity of chain-lengthening agents.  The polyhydroxy compound may be a polyester, polyesteramide, polyether, polyacetal or a poly-N-alkyl urethane, those exemplified being a polyester derived from adipic acid and a mixture of hexane-1,6-diol and 2,2-dimethylpentane-1,3-diol and a polyether which is a polytetramethylene ether diol. Aromatic and aliphatic diisocyanates may be used, more preferably diphenylmethane-4,41-diisocyanate. The organic chain-lengthening agent containing reactive hydrogen atoms may be e.g. ethylene diamine, carbodihydrazide, water and hydrazine hydrate.  Suitable further chain-lengthening agents are o ,o 1-diamino-amides, o ,o 1 - diaminourethanes, o ,o 1-diaminoureas, o ,o 1 - diamino - acylsemi-carbazides, o ,o 1 - diaminocarbazinic acid esters, o ,o 1 - diaminohydrazodicarbonamides and o ,o 1 - diamino - hydrazodicarboxylic acid esters of which many are exemplified.  The preferred solvents are those containing amide, sulphoxide or sulpho groups especially N,N-dimethylformamide.ALSO:Primary or secondary diamines of the formula <FORM:1090710/C2/1> wherein A denotes amide, urethane, urea, acyl semicarbazide, acyl carbazinic ester, hydrazodicarbonamide, hydrazodicarboxylic ester amide groups which may be substituted with alkyl sulphonate groups, R1 is hydrogen, alkyl or alkyl-sulphonate groups, R2 and R3, which may be the same or different, each represent an alkylene, cycloalkylene, arylene or aralkylene radical which may be interrupted by hetero atoms and/or closed to a ring and/or substituted by sulphonate groups, and n is 0 or an integer from 1 to 5 may be prepared by the following methods. o ,o -Diaminoamides from o -aminocarboxylic acid esters or lactams or dicarboxylic acid esters and diamines, those exemplified being (2) bis - (o  - aminoethyl) - succinamide from diethyl succinate and ethylene diamine; (6) an o ,o 1-diprimary ditertiary aminosuccinamide from diethyl succinate and g ,g 1-diaminopropyl-N-methylamine; (9) the sodium salt of bis-(6 - aminohexyl - 3 - sulphonic acid) - succinamide from diethyl succinate and sodium 1,6-diamino-3-sulphonate, and (10) the diaminoadipic acid amide of the K salt of g ,g 1-diaminopropyl - N - methylamine - (N1,g ) - butyl-sulphonic acid by adding diethyl adipate to the said amine, followed by reaction with KOH.  o ,o 1 - Diaminourethanes from diisocyanates and aminoalcohols with blocked amino groups, followed by liberation of the amino group or from carbobenzoxy-alkanolamines and nitro- or nitrile isocyanates with subsequent hydrogenolysis of the carbobenzoxy radical and reduction of the nitro or nitrile group or from cyanohydrins or hydroxyalkyl nitriles with isocyanates or nitro- or nitrile monoisocyanates, followed by reduction or from diamines or aminonitriles with bischlorocarbonic acid esters or monochlorocarbonic acid esters of cyanohydrins or hydroxyalkyl nitrites, those exemplified being (11) that of the formula <FORM:1090710/C2/2> from b -hydroxy propionitrile and hexane 1,6-diisocyanate, followed by reduction of the diurethane-dinitrile, and (12) that of the formula <FORM:1090710/C2/3> from ethylene-bis-chloroformic acid ester and b -aminopropionitrile, followed by reduction.  o ,o 1-Diaminoureas from diamines or aminonitriles with phosgene, carbonic acid esters, diisocyanates or biscarbamidic acid phenyl esters followed by reduction of the nitrile groups, those exemplified being (1) bis-(o -aminohexyl) urea from o -cyanopentylamine and phosgene, followed by reduction (3) that from hexamethylene-bis-carbamidic acid phenyl ester and g ,g 1-diaminopropyl-N-methylamine, (13) that of the formula <FORM:1090710/C2/4> from 2-aminomethyl-pyridine and diphenyl carbonate, followed by hydrogenation, and (14) that of the formula <FORM:1090710/C2/5> from N,N, - diethyl - N1,N1 - bis - (g  - aminopropyl)-propylene-1,3-diamine and diphenylcarbonate.  o ,o 1-Diamino-acylsemicarbazides from dicarboxylic acid hydrazides and diamines or carbamidic acid phenyl esters of aminonitriles, followed by reduction or from amino acid phenyl esters and bis-semicarbazides or from o -nitrile-semicarbazides and esters of amino acids, followed by reduction.  o ,o 1-Diaminoacyl-carbazinic acid esters from amino acid esters and bis-carbazinic acid esters or o -nitrile-carbazinic acid esters, followed by reduction.  o ,o 1 - Diamino - hydrazodicarbonamides from phenol splitters of bis-semicarbazides and diamines or aminonitriles or amino acid phenyl esters; from hydrazodicarboxylic acid phenyl esters and a diamine; from bis-carbazinic acid esters and diamines or aminonitriles; from bis-semicarbazides and o -cyano-alkyl-chlorocarbonic acid esters or from o -nitrile semicarbazides and amino acid esters, those exemplified being the reaction products of hydrazodicarboxylic acid phenyl ester and (4) g ,g 1-diamino-propyl-N-methylamine, and (5) g ,g 1-diamino-propyl piperazine.