EP0306831A1 - Use of polyaralkyl amines as corrosion inhibitors - Google Patents

Abstract

It has been found out that polyaralkylamines of the formula stated in the claims are useful as corrosion inhibitors for metallic materials; furthermore were found out new polyaralkylamines of the formula stated in the claims and a process for their preparation.

Description

The invention relates to the use of polyaralkylamines as corrosion inhibitors for metallic materials as well as new polyaralkylamines and processes for their production.

It is known to use long-chain polyamines, especially those derived from longer fatty acids, as protective film-forming corrosion inhibitors (see, for example, T. Szauer, A. Brandt, Corrosion Science, Vol. 23, No. 5, 473-480 (1983) ; M. Duprat et al., Corrosion, Vol. 36, 262-266 (1981); U.S. Patent Nos. 3,718,604, 3,717,433 and 3,687,859). The effects are particularly notable for those derived from cyclic or polycyclic higher carboxylic acids, for example naphthenic acids or resin acids. However, naphthenic or resin acids are not freely accessible as natural products. In addition, their quality varies greatly with the respective origin.

On the other hand, amines with a short chain length or unsubstituted polyalkylene amines usually show no or insufficient corrosion-inhibiting effect on metallic materials.

worin
R¹ bis R⁴ gleich oder verschieden sind und Wasserstoff, C₁-C₁₈-Alkyl, C₅-C₁₂-Cycloalkyl, C₇-C₁₈-Aral­kyl, Poly-C₇-C₁₈-aralkyl mit 2 bis 50 Aralky­leneinheiten oder C₆-C₁₅-Aryl bedeuten oder
R¹ bis R⁴ untereinander so verknüpft sind, daß jeweils zwei der Reste zusammen mit dem sie verbinden­den Stickstoffatom oder mit der N-C-haltigen Restkette einen 5- bis 6-gliedrigen Ring bil­den, wobei mindestens einer der Reste R¹ bis R⁴ C₇-C₁₈-Aralkyl oder Poly-C₇-C₁₈-Aralkyl be­deutet, und
R⁵ und R⁶ unabhängig voneinander Wasserstoff, C₁-C₆-­Alkyl, C₅-C₇-Cycloalkyl, C₇-C₁₂-Aralkyl oder C₆-C₁₀-Aryl bedeuten,
m für eine ganze Zahl von 2 bis 10 steht und
n 0 bis 30 bedeutet,
wobei, wenn n = 0 mindestens einer der Reste R¹, R² und R⁴ Polyaralkyl bedeutet, die mit m definierte C-Kette unterschiedliche Reste R⁵ und R⁶ und die durch n definierte C-N-Kette verschiedene Werte für m besitzen kann,
als Korrosionsinhibitoren für metallische Werkstoffe.The present invention relates to the use of polyaralkylamines of the formula

wherein
R¹ to R⁴ are the same or different and are hydrogen, C₁-C₁₈ alkyl, C₅-C₁₂ cycloalkyl, C₇-C₁₈ aralkyl, poly-C₇-C₁₈ aralkyl having 2 to 50 aralkylene units or C₆-C₁₅ aryl or
R¹ to R⁴ are linked so that two of the radicals together with the nitrogen atom connecting them or with the NC-containing chain form a 5- to 6-membered ring, at least one of the radicals R¹ to R⁴ C₇-C₁₈-aralkyl or Poly-C₇-C₁₈ aralkyl means, and
R⁵ and R⁶ independently of one another are hydrogen, C₁-C₆-alkyl, C₅-C₇-cycloalkyl, C₇-C₁₂-aralkyl or C₆-C₁₀-aryl,
m represents an integer from 2 to 10 and
n means 0 to 30,
where, if n = 0, at least one of the radicals R¹, R² and R⁴ is polyaralkyl, the radical R⁵ and R⁶ defined with m and the CN chain defined by n can have different values for m,
as corrosion inhibitors for metallic materials.

Suitable alkyl radicals of the formula (I) are those having 1 to 18 carbon atoms, preferably 1 to 12 carbon atoms, particularly preferably 1 to 6 carbon atoms. Called his: methyl, ethyl, propyl, n-butyl, isobutyl, hexyl, ethylhexyl, decyl and stearyl, preferably methyl, ethyl, n-butyl and ethylhexyl, particularly preferably methyl, ethyl and n-butyl.

Suitable cycloalkyl radicals are those having 5 to 12 carbon atoms, preferably 5 to 7 carbon atoms. Called his: Cyclohexyl and Methylcyclohexyl.

Suitable aralkyl radicals are those having 7 to 18 carbon atoms, preferably having 7 to 12 carbon atoms, particularly preferably those having 7 to 9 carbon atoms. The following may be mentioned: benzyl, α-methylbenzyl, α, α-dimethylbenzyl, 4-methylbenzyl, tert-butylbenzyl, methoxybenzyl and 3-chlorobenzyl, preferably benzyl.

Suitable polyaralkyl radicals are those with 7 to 18 carbon atoms per aralkylene unit, preferably those with 7 to 12 carbon atoms, particularly preferably those with 7 to 9 carbon atoms. The polyaralkyl radicals generally have 2 to 50 aralkylene units, preferably 2 to 30 aralkylene units, particularly preferably 2 to 12 aralkylene units.

Suitable aryl radicals are those with 6 to 15 carbon atoms, preferably those with 6 to 12 carbon atoms, particularly preferably those with 6 to 8 carbon atoms. The following may be mentioned: phenyl, tolyl and chlorophenyl, preferably phenyl.

The radicals R¹ to R⁴, which may be linked to one another by a nitrogen atom connecting them, are the piperidinyl radical

The radicals R¹ to R⁴ which can be linked to one another with the NC-containing residual chain are the piperazinylene radical

Preference is given to using polyaralkylamines of the formula (I) in which m is an integer from 2 to 6, particularly preferably 2 and 3 and n is 1 to 20, particularly preferably 2 to 10.

wobei
R für Wasserstoff,

Methyl, Ethyl, n-Butyl, iso-Butyl, Stearyl, Cyclo­hexyl, Phenethyl, Phenyl, Chlorphenyl oder Tolyl steht,
X Wasserstoff, Methyl, Chlor oder Methoxy bedeutet,
p für 2 bis 50 und
n für 1 bis 8 steht.Corrosion-inhibiting polyaralkylamines include the following, for example:

in which
R for hydrogen,

Is methyl, ethyl, n-butyl, isobutyl, stearyl, cyclohexyl, phenethyl, phenyl, chlorophenyl or tolyl,
X represents hydrogen, methyl, chlorine or methoxy,
p for 2 to 50 and
n stands for 1 to 8.

For example, the following polyaralkylamines are mentioned by name: di-, tri-, tetra- and pentabenzyl-diethylenetriamine, -triethylenetetramine, -tetraethylenepentamine, -pentaethylenehexamine, -heptaethyleneoctamine, -N, N'-bis-aminoethyl-propylenediamine and -N, N'- bisaminopropylethylene diamine, perbenzyl triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine, hexaethylene heptamine, aminoethyl piperazine and aminopropyl piperidine, tetrabenzyl stearyl diethylene triamine and pentaethylene hexamine, tribenzyl cyclohexyl triethylene pentamines, monenzenzyl cyclohexyl triethylene pentamine -, bis- and tris- (polybenzyl) -diethylene triamine, -triethylene tetramine, -tetraethylenepentamine, -pentaethylenehexamine, -heptaethyleneoctamine, -1,2- and 1,3-dipropylenetriamine, -tripropylenetetramine, -stearyl-hexamethylenediamine, -N, N ′ -bis-aminoethylpropylenediamine, N, N'-bis-aminopropyl-ethylenediamine, -aminoethylpiperazine, and -aminopropylpiperidine, (polybenzyl) -tetrabenzyl-diethylenetriamine, -triethyle ntetramine, -tetraethylenepentamine and -N, N'-bis-aminoethyl-propylenediamine, (polybenzyl) -hexabenzyl-tetraethylenepentamine, -pentaethylenehexamine and -hexaethyleneheptamine, (polybenzyl) -tetrabenzyl-1,2- and 1,3-dipropylenetriamine, bis- (polybenzyl) -tribenzyl-diethylenetriamine, -dipropylenetriamine, -tetraethylenpentamine and -N, N′-bis-aminopropyl-ethylenediamine, bis- (polybenzyl) -pentabenzyl-tetraethylenepentamine and -heptaethylenoctamine, tris- (polybenzyl) -tribenzamine-triethylentetramine -tetraethylenpentamine and -pentaethylenhexamin, bis- (polybenzyl) -dibenzyl-phenyl-dipropylenetriamine and (poly-methylbenzyl) -di-methylbenzyl-diethylenetriamine.

The corrosion-inhibiting polyaralkylamines can be used both individually and in any mixtures with one another and in a mixture with other inhibitors to protect against corrosion in metallic materials. Additional, known corrosion inhibitors are: fatty amines, quaternary ammonium salts, N-heterocycles, such as imidazolines, imidazoles, thiazoles, triazoles and alkynols, such as propargyl alcohol, and phosphonic acids.

The polyaralkylamines of the formula (I) and the corrosion inhibitors mentioned can be used in any mixing ratio with one another. Preferred mixing ratios can easily be determined by appropriate preliminary tests.

The polyaralkylamines of the formula (I) according to the invention can be added to all media which have a corrosive action on these materials in order to protect them against corrosion in metallic materials. Examples of corrosive media are: heat transfer media (cooling and heating fluids), hydraulic fluids, petroleum (fractions), fuels and fuels, metalworking fluids or emulsions, acids for cleaning, pickling and for acidifying boreholes in oil extraction "acidizing", metal coating medium and plastics, for example as insulation or when processing at higher temperatures, for example during extrusion.

As metallic materials that can be protected against corrosion, e.g. called: ferrous metals (cast or steel), copper, brass, zinc, lead and aluminum, preferably ferrous metals and copper, very particularly preferably ferrous metals.

The amount of polyaralkylamines of the formula (I) to be used can be varied within a wide range and depends in particular on the type of the corrosive medium. As a rule, the polyaralkylamines are used in an amount of about 0.001 to 3% by weight, preferably 0.05 to 1% by weight, based on the corrosive medium.

The polyaralkylamines of the formula (I) are preferably used in combination with customary formulation agents, such as solvents and dispersants. The following may be mentioned as solvents and dispersants: aliphatic or araliphatic alcohols, such as isooctanol and benzyl alcohol, amides, such as dimethylformamide, ethoxylated derivatives of alcohols or amines, such as 2-ethylhexanol, lauryl alcohol, cetyl alcohol, dodecylamine, tallow fatty amine and nonylphenol.

The most favorable amount of solvent and / or dispersant can easily be determined by preliminary tests.

worin
R⁷ bis R¹⁰ gleich oder verschieden sind und Wasserstoff, C₁-C₁₈-Alkyl, C₅-C₁₂-Cycloalkyl, C₇-C₁₈-Aral­kyl, Poly-C₇-C₁₈-aralkyl mit 2 bis 50 Aralky­leneinheiten oder C₆-C₁₅-Aryl bedeuten oder
R⁷ bis R¹⁰ untereinander so verknüpft sind, daß jeweils zwei der Reste zusammen mit dem sie verbinden­den Stickstoffatom oder mit der N-C-haltigen Restkette einen 5- bis 7-gliedrigen Ring bil­den, wobei mindestens einer der Reste R⁷ bis R¹⁰ Poly-C₇-C₁₈-aralkyl mit 2 bis 50 Aral­kyleneinheiten bedeutet,
R⁵ und R⁶ unabhängig voneinander Wasserstoff, C₁-C₆-Al­kyl, C₅-C₇-Cycloalkyl, C₇-C₁₂-Aralkyl oder C₆-­C₁₀-Aryl bedeuten,
m für eine ganze Zahl von 2 bis 10 steht und
n 0 bis 30 bedeutet, wobei die mit m definierte C-Kette unter­schiedliche Reste R⁵ und R⁶ und die durch n definierte C-N-Kette verschiedene Werte für m besitzen kann.Another object of the present invention are new polyaralkylamines of the formula

wherein
R⁷ to R¹⁰ are the same or different and are hydrogen, C₁-C₁₈-alkyl, C₅-C₁₂-cycloalkyl, C₇-C₁₈-aralkyl, poly-C₇-C₁₈-aralkyl with 2 to 50 aralkylene units or C₆-C₁₅-aryl or
R⁷ to R¹⁰ are linked to one another in such a way that two of the radicals together with the nitrogen atom connecting them or with the NC-containing residual chain form a 5- to 7-membered ring, at least one of the radicals R⁷ to R¹₈ poly-C₇-C₁₈- aralkyl means 2 to 50 aralkylene units,
R⁵ and R⁶ independently of one another are hydrogen, C₁-C₆-alkyl, C₅-C₇-cycloalkyl, C₇-C₁₂-aralkyl or C₆-C₁₀-aryl,
m represents an integer from 2 to 10 and
n means 0 to 30, where the C chain defined by m can have different radicals R⁵ and R⁶ and the CN chain defined by n can have different values for m.

wobei
R für Wasserstoff,

Methyl, Ethyl, n-Butyl, iso-Butyl, Stearyl, Cyclo­hexyl, Phenethyl, Phenyl, Chlorphenyl oder Tolyl steht,
X Wasserstoff, Methyl, Chlor oder Methoxy bedeutet,
p für 2 bis 50 und
n für 1 bis 8 steht,
und mindestens einer der Reste R

bedeutet.The following are mentioned as new polybenzylamines, for example:

in which
R for hydrogen,

Is methyl, ethyl, n-butyl, isobutyl, stearyl, cyclohexyl, phenethyl, phenyl, chlorophenyl or tolyl,
X represents hydrogen, methyl, chlorine or methoxy,
p for 2 to 50 and
n stands for 1 to 8,
and at least one of the radicals R

means.

The following polyaralkylamines may be mentioned by name: mono-, bis- and tris- (polybenzyl) -diethylene triamine, -triethylene tetramine, -tetraethylenepentamine, -pentaethylenehexamine, -heptaethyleneoctamine, -1,2- and 1,3-dipropylenetriamine, -tripropylenetetramine, -stearyl- hexamethylenediamine, -N, N'-bis-aminoethyl-propylenediamine, -N, N'-bis-aminopropyl-ethylenediamine, -aminoethylpiperazine and -aminopropylpiperidine, (polybenzyl) -tetrabenzyldiethylenetriamine, -triethylenetetramine, -tetraethylenepentamine and -N, N' bis-aminoethyl-propylene diamine, (polybenzyl) hexabenzyl tetraethylene pentamine, pentaethylene hexamine and hexaethylene heptamine, (polybenzyl) - tetrabenzyl-1,2- and 1,3-dipropylenetriamine, bis- (polybenzyl) -tribenzyl-diethylenetriamine, -dipropylenetriamine, -tetraethylenepentamine and -N, N′-bis-aminopropyl-ethylenediamine, bis- (polybenzyl) -pentabenzyl-tetraethylenepentamine and -heptaethylenoctamine, tris- (polybenzyl) -tribenzyl-triethylenetetramine, - tetraethylenepentamine and -pentaethylenehexamine, bis- (polybenzyl) -dibenzyl-phenyldipropylenetriamine and (poly-methylbenzyl) -di-methylbenzyl-diethylenetriamine.

worin
R⁷ bis R¹⁰ gleich oder verschieden sind und Wasserstoff, C₁-C₁₈-Alkyl, C₅-C₁₂-Cycloalkyl, C₇-C₁₈-Aral­kyl, Poly-C₇-C₁₈-aralkyl mit 2 bis 50 Aralky­leneinheiten oder C₆-C₁₅-Aryl bedeuten oder
R⁷ bis R¹⁰ untereinander so verknüpft sind, daß jeweils zwei der Reste zusammen mit dem sie verbinden­den Stickstoffatom oder mit der N-C-haltigen Restkette einen 5- bis 7-gliedrigen Ring bil­den, wobei mindestens einer der Reste R⁷ bis R¹⁰ Poly-C₇-C₁₈-aralkyl mit 2 bis 50 Aral­kyleneinheiten bedeutet,
R⁵ und R⁶ unabhängig voneinander Wasserstoff, C₁-C₆-Al­kyl, C₅-C₇-Cycloalkyl, C₇-C₁₂-Aralkyl oder C₆-­C₁₀-Aryl bedeuten,
m für eine ganze Zahl von 2 bis 10 steht und
n 0 bis 30 bedeutet,
wobei die mit m definierte C-Kette unter­schiedliche Reste R⁵ und R⁶ und die durch n definierte C-N-Kette verschiedene Werte für m besitzen kann,
das dadurch gekennzeichnet ist, daß man Amine der Formel (III)

worin
R¹¹ bis R¹⁴ gleich oder verschieden sind und Wasser­stoff, C₁-C₁₈-Alkyl, C₅-C₁₂-Cycloalkyl, C₇-C₁₈-Aralkyl oder C₆-C₁₅-Aryl bedeuten oder
R¹¹ bis R¹⁴ untereinander so verknüpft sind, daß je­weils zwei der Reste zusammen mit dem sie verbindenden Stickstoffatom oder mit der N-C-haltigen Restkette einen 5- bis 7-­gliedrigen Ring bilden, wobei mindestens einer der Reste R¹¹ bis R¹⁴ Wasserstoff bedeutet, und
R⁵, R⁶, m und n die oben genannte Bedeutung besitzen,
mit Poly-C₇-C₁₈-Aralkylhalogeniden der Formel (IV)

worin
R¹⁵ für Wasserstoff, Halogen, C₁-C₄-Alkoxy oder C₁-C₆-Alkyl steht,
R¹⁶ und R¹⁷ gleich oder verschieden sind und Wasserstoff oder C₁-C₆-Alkyl bedeuten,
p für eine ganze Zahl von 2 bis 50 steht und
X für Halogen steht,
gegebenenfalls gemeinsam mit Mono-C₇-C₁₈-aralkylhaloge­niden der Formel (V)

worin
R¹⁵ bis R¹⁷ und X die obengenannte Bedeutung besitzen und
p 1 bedeutet,
umsetzt.The invention also relates to a process for the preparation of new polyaralkylamines of the formula (II)

wherein
R⁷ to R¹⁰ are the same or different and are hydrogen, C₁-C₁₈-alkyl, C₅-C₁₂-cycloalkyl, C₇-C₁₈-aralkyl, poly-C₇-C₁₈-aralkyl with 2 to 50 aralkylene units or C₆-C₁₅-aryl or
R⁷ to R¹⁰ are linked to one another in such a way that two of the radicals together with the nitrogen atom connecting them or with the NC-containing residual chain form a 5- to 7-membered ring, at least one of the radicals R⁷ to R¹₈ poly-C₇-C₁₈- aralkyl means 2 to 50 aralkylene units,
R⁵ and R⁶ independently of one another are hydrogen, C₁-C₆-alkyl, C₅-C₇-cycloalkyl, C₇-C₁₂-aralkyl or C₆-C₁₀-aryl,
m represents an integer from 2 to 10 and
n means 0 to 30,
where the C chain defined by m can have different radicals R⁵ and R⁶ and the CN chain defined by n can have different values for m,
which is characterized in that amines of the formula (III)

wherein
R¹¹ to R¹⁴ are the same or different and are hydrogen, C₁-C₁₈ alkyl, C₅-C₁₂ cycloalkyl, C₇-C₁₈ aralkyl or C₆-C₁₅ aryl or
R¹¹ to R¹⁴ are linked together so that two of the radicals together with the nitrogen atom connecting them or with the NC-containing residual chain form a 5- to 7-membered ring, at least one of the radicals R¹¹ to R¹⁴ being hydrogen, and
R⁵, R⁶, m and n have the meaning given above,
with poly-C₇-C₁₈ aralkyl halides of the formula (IV)

wherein
R¹⁵ represents hydrogen, halogen, C₁-C₄-alkoxy or C₁-C₆-alkyl,
R¹⁶ and R¹⁷ are the same or different and are hydrogen or C₁-C₆-alkyl,
p represents an integer from 2 to 50 and
X represents halogen,
optionally together with mono-C₇-C₁₈ aralkyl halides of the formula (V)

wherein
R¹⁵ to R¹⁷ and X have the meaning given above and
p 1 means
implements.

In addition to ammonia, the following are possible primary and secondary amines of the formula (III):
Methyl, ethyl, butyl, isooctyl, dodecyl, stearyl, allyl, cyclohexyl and benzylamine, dimethyl, dibutyl, methylcyclohexyl, methylbenzyl and ethyldodecylamine, aniline, N- Methyl, N-ethyl and N-butyl aniline, ethylenediamine, methyl, dimethyl, isooctyl, stearyl, cyclohexyl, allyl, benzyl, phenyl-ethylenediamine, 1,2- and 1,3- Propylene diamine, methyl propyl dodecyl, palmityl, cyclohexyl, phenyl 1,2 and 1,3 propylene diamine, butylene diamine, N-stearyl butylene diamine, 2,5-diamino-2,5-dimethyl hexane, hexamethylene diamine, N- Cyclohexyl-hexamethylene diamine, trimethyl-1,6-hexamethylene diamine, octamethylene diamine, diethylene triamine, dipropylene triamine, N-aminoethyl propylene diamine, dihexylene triamine, triethylene tetramine, tripropylene tetramine, N, N'-bis (aminopropyl) ethylenediamine, N, N'-bis (aminoethyl) propylene diamine, N, N'-bis (aminopropyl) butylene diamine, tetraethylene pentamine, pentaethylene hexamine, hexaethylene heptamine, heptaethylene octamine , Mixtures of higher polyethylene polyamines (distillation residue from ethylene polyamine production), N-methyl, N-stearyl, N-cyclohexyl, N-phenyl, N, N'-dilauryl-dipropylenetriamine, N, N'-dipalmitine-pentaethylene hexamine, diaminocyclohexane, Isophoronediamine, piperidine, N-aminoethyl, N-aminopropyl, N-aminoethylaminoethyl piperidine, piperazine, N-methyl, N-phenyl, N-benzyl, N-aminoethyl, N-aminopropyl, N, N '-Bis-aminoethyl- and N, N'-bis-aminopropylpiperazine, preferably ammonia, methylamine, allylamine, aniline, ethylenediamine, propylenediamine, N-methylpropylenediamine, N-phenylpropylenediamine, butylenediamine, hexamethylenediamine, diethylenetriamine, n-dipylenediamine diamine, dipropylenediamine diamine, dipropylenediamine diamine , Tripropylenetetramine, N, N'-bis (aminopropyl) ethylenediamine, N, N ' - bis (aminoethyl) propylene diamine, tetraethylene pentamine, pentaethylene hexamine, hexaethylene heptamine, isophorone diamine, piperidine, piperazine and N-aminoethyl-piperazine.

As poly-C₇-C₁₈ aralkyl halides with 2 to 50 aralkylene units of the formula IV (p> 1) are those which are derived from benzyl chloride, benzyl bromide, the o-, m- and p-isomers of methyl, ethyl and butyl - Derive, chlorine, methoxy-benzyl chloride and α-methyl and α, α-dimethylbenzyl chloride, preferably benzyl chloride.

The amines of the formula (III) are generally reacted in a stoichiometric ratio with the aralkyl halides of the formula (IV). However, it can also be advantageous to use an excess of amines of the formula (III) (2 to 10 mol of amine per mol of aralkyl halide) and to remove excess amine again after the reaction has ended. This is preferably done by distillation in vacuo.

The reaction of the amines with the aralkyl halides can be carried out without the use of special hydrogen halide acceptors. In this case, the hydrohalides of the process products according to formula (II) are obtained. In general, however, condensation is carried out in the presence of customary hydrogen halide acceptors, for example in the presence of tertiary amines, preferably in the presence of alkali metal hydroxides and / or carbonates.

The amines can be reacted in bulk without the presence of special solvents. Of course, solvents or mixtures thereof can also be used. As such, e.g. Water, hydrocarbons such as petroleum ether, cyclohexane, ligroin, benzene, toluene, xylene, chlorinated hydrocarbons such as methylene chloride, chloroform, tri- and tetrachloroethane, chlorobenzene, dichlorobenzene, esters such as ethyl or butyl acetate. Alcohols such as methanol, ethanol, isopropanol and methyl glycol.

The reaction temperatures can be varied within wide limits. They are generally from -20 to 200 ° C., preferably from 20 to 120 ° C.

The isolation of the new polyaralkylamines of the formula (II) depends on whether the hydrohalides or the free bases of the amines of the formula (II) are desired. If the hydrohalides are desired, any excess amine is separated off by vacuum distillation. The remaining residues are generally resinous; in many cases they can be made into aqueous and / or alcoholic, i.e. Process colloidal solutions.

If the free amine bases are desired, they are generally obtained in solution in an organic solvent when using alkali metal hydroxides as hydrogen halide acceptors. They can be processed as such or isolated by distilling off the solvent.

worin
R¹⁵ für Wasserstoff, Halogen, C₁-C₄-Alkoxy oder C₁-C₆-Alkyl steht,
R¹⁶ und R¹⁷ gleich oder verschieden sind und Wasserstoff oder C₁- bis C₆-Alkyl bedeuten,
p für eine ganze Zahl von 2 bis 50 steht und
X für Halogen steht,
das dadurch gekennzeichnet ist, daß man Mono-C₇- bis C₁₈-Aralkylhalogenide der Formel (V)

worin
R¹⁵ bis R¹⁷ und X die obengenannte Bedeutung besitzen und
p = 1 ist,
in Gegenwart von Kondensationsmitteln bis zu einem Um­satz von 5 bis 70 Mol-% der abzuspaltenden Menge an Halogenwasserstoff kondensiert und gegebenenfalls die nicht umgesetzte Menge an Ausgangsprodukt abtrennt.The present invention finally relates to a process for the preparation of poly-C₇-C₁₈ aralkyl halides of the formula (IV)

wherein
R¹⁵ represents hydrogen, halogen, C₁-C₄-alkoxy or C₁-C₆-alkyl,
R¹⁶ and R¹⁷ are identical or different and are hydrogen or C₁- to C₆-alkyl,
p represents an integer from 2 to 50 and
X represents halogen,
which is characterized in that mono-C₇ to C₁₈ aralkyl halides of the formula (V)

wherein
R¹⁵ to R¹⁷ and X have the meaning given above and
p = 1,
condensed in the presence of condensing agents up to a conversion of 5 to 70 mol% of the amount of hydrogen halide to be split off and, if appropriate, the unreacted amount of starting product is separated off.

Examples of condensing agents that can be used are: iron, zinc, ferric chloride, ferric oxide and ferric oxide, zinc chloride, zinc acetate, zinc stearate, aluminum chloride, aluminum oxide, silicon dioxide, clays, such as Montmoril lonite and / or zeolite. Zinc chloride and / or zinc stearate are preferably used.

The condensing agents are usually used in catalytic amounts, for example in amounts of 0.01 to 1, preferably 0.1 to 0.5 wt .-%, based on the C₇-C₁₈ monoaralkyl halide (V) used.

The aralkyl halides are preferably condensed up to a conversion of 10 to 50 mol%, particularly preferably up to a conversion of 15 to 40 mol%, of the amount of hydrogen halide to be split off.

The conversion of the condensation reaction according to the invention is controlled, for example, by determining the amount of hydrogen halide split off. This can e.g. by means of rotameters or by titration. To control the condensation by stopping the hydrogen halide elimination, inhibitors or deactivators are usually added to the condensation reaction. Examples include the following as inhibitors or deactivators: quaternary ammonium salts, amines and / or amides, such as caprolactam and / or phosphines, such as triphenylphosphine.

The condensation reaction according to the invention is generally carried out in bulk; can also be carried out with the participation of suitable solvents, for example chlorinated hydrocarbons, such as methylene chloride and / or chloroform. It can be carried out continuously or batchwise.

The reaction temperature can be varied within wide limits depending on the type and / or the amount of the condensing agent and in view of the desired degree of condensation. It is generally about -50 to 200 ° C, preferably 0 to 180 ° C, particularly preferably 50 to 150 ° C.

The unreacted monoaralkyl halide of the formula (V) can be separated off from the condensation mixture, for example by vacuum distillation.

Manufacturing examples example 1

126.6 g (1 mol) of benzyl chloride and 0.2 g of Zn stearate are heated to 80-110 ° C., with vigorous HCl evolution starting. After splitting off 0.25 mol of HCl (titration against sodium hydroxide solution), the reaction is stopped by adding 0.2 g of triphenylphosphine. Excess benzyl chloride is distilled in vacuo. (80 g / 0.63 mol), the resin is taken up in 100 ml of toluene and the solution is added dropwise at 25-35 ° C. to 103 g (1 mol) of diethylene triamine. The solvent is then distilled off in vacuo at normal pressure up to a bottom temperature of 200 ° C., then excess diethylenetriamine. In this way 44 g (d100% of theory) of a yellow-orange water-soluble resin are obtained. C₃₉H₄₄ClN₃ (590.3) Ber. C. 79.36% H 7.51% Cl 6:00 am% N 7.12% Gef. 79.09 7.60 6.18 7.20

To obtain the free base, the hydrochloride is taken up in approx. 300 ml of toluene and shaken out with dilute sodium hydroxide solution (∼0.2 mol). After drying and concentrating the toluene phase in vacuo, 37 g of a slightly cloudy brownish viscous oil are obtained.

Example 2

According to the procedure of Example 1, using 232 g (1 mol) of pentaethylene hexamine instead of diethylene triamine gives 53.5 g (∼100%) of a yellow-orange water-soluble resin (as hydrochloride). C₄₅H₅₉ClN₆ (719.5) Ber. C. 75.12% H 8.27% Cl 4.93% N 11.69% Gef. 74.89 8.33 4.69 11.80

Example 3

After adding 5.25 g of Zn stearate, 4431 g (35 mol) of benzyl chloride are heated to 80-100 ° C. with stirring, vigorous HCl being released. After splitting off 7 mol (20%) of HCl (titration with sodium hydroxide solution), the reaction is stopped by adding 7 g of caprolactam and excess benzyl chloride is distilled off in vacuo to a bottom temperature of approx. 100 ° C. 3080 g (24.3 mol) of benzyl chloride and 1076.5 g of a brownish, faintly fluorescent oil with a reactive Cl content of 9.05% are obtained.

Example 4

Analogously to Example 3, splitting off 10.5 mol (30%) of HCl gives 2668 g (21 mol) of benzyl chloride in addition to 1370 g of a brownish oil with a reactive Cl content of 7.25%.

Example 5

Analogously to Example 3, splitting off 14 mol (40%) of HCl gives 2288 g (18 mol) of benzyl chloride and 1630 g of a green-yellow fluorescent viscous oil with a reactive Cl content of 5.6%.

Example 6

50 g (0.1 mol) of the polybenzyl chloride according to Example 4 are added dropwise in 30 minutes at 50-80 ° C. with stirring to 23.2 g (0.1 mol) of pentaethylene hexamine. After ∼2 h after-reacting at 80 ° C, a water-soluble light yellow-brown resin is obtained (yield 100%).
C₄₅H₅₉ClN₆ (719.5) Ber. C. 75.12% H 8.27 Cl 4.93 N 11.69 Gef. 75.51 8.20 4.69 11.48

Example 7

In the same way as in Example 6, 50 g of the polybenzyl chloride according to Example 4 are reacted with 18.9 g (0.1 mol) of tetraethylene pentamine: 68.9 g (∼100%) of a light yellow-brown resin which is soluble in water with a slightly cloudy opaque consistency is. C₄₃H₅₄ClN₅ (676.4) Ber. C. 76.35% H 8.05% Cl 5.24% N 10.35% Gef. 76.59 7.95 5.12 10.18

Example 8

126.6 g (1 mol) of benzyl chloride and 0.2 g of Zn stearate are heated to 80-110 ° C. The vigorous development of HCl is stopped after reaching 50% (0.5 mol) elimination by adding 0.2 g of caprolactam. Excess benzyl chloride is distilled off in vacuo (approx. 46 g), the remaining resin is taken up in 150 ml of toluene and the solution is run into 116 g (0.5 mol) of pentaethylene hexamine at ∼25 - 30 ° C while stirring. While heating to boiling, solvent is removed under normal pressure and excess amine in an oil pump vacuum up to a bottom temperature of 250 ° C. 80.9 g (99% of theory) of a brownish, viscous, water-soluble resin are obtained. C₆₆H₇₇ClN₆ (989.85) Ber. C. 80.08% H 7.84% Cl 3.58% N 8.49% Gef. 80.25 7.70 3.39 8.28

The conversion into the free base analogously to Example 1 gives 72.2 g of a yellow-green fluorescent oil.

With the same procedure as in Example 8, the degrees of benzyl chloride condensation are varied in the following examples: E.g. % Cleavage HCl Benzyl resin polyamine.HCl free base 9 66 46.9 g (98%) 45.0 g C₇₃H₈₃ClN₆ (1080.0) Ber. C. 81.19% H 7.75% Cl 3.28% N 7.78% Gef. 80.87 7.77 2.95 7.93 10th 75 97.3 g (99.7%) - C₈₀H₈₉ClN₆ (1170.1) Ber. C. 82.12% H 7.67% Cl 3.03% N 7.18% Gef. 82.37 7.51 2.94 7.23

Example 11

253.2 g (2 mol) of benzyl chloride are kept together with 0.4 g of Zn stearate at 105-115 ° C. until 0.5 mol (25%) of HCl has been eliminated. The reaction is stopped by adding 0.4 g of triphenylphosphine, excess benzyl chloride is distilled off in vacuo to a bottom temperature of about 110 ° C., the resinous residue is taken up in 150 ml of toluene and the solution is left at 20-30 ° C. run into 146.2 g (1 mol) of triethylenetetramine with stirring. After heating to reflux, the solvent is distilled under normal pressure to a bottom temperature of about 200 ° C, then the excess triethylenetetramine in a high vacuum to the same temperature. 98.8 g (96.4% of theory) are obtained. a sticky water-soluble resin which, after shaking with 500 ml of toluene and 150 ml in sodium hydroxide solution, gives 77.8 g of the corresponding free amine base as an orange-brown resin.
Hydrochloride: C₃₄H₄₃ClN₄ (543.2) Ber. C. 75.18% H 7.98% Cl 6.53% N 10.31% Gef. 75.30 7.81 6.37 10.12

In the following examples, the procedure is analogous to Example 11 and the benzyl chloride condensation is varied: E.g. % Separation HCl Benzyl resin polyamine.HCl free base 12 33 104.1 g (89.2%) 86.4 g C₄₈H₅₅ClN₄ (723.5) Ber. C. 79.69% H 7.66% Cl 4.90% N 7.75% Gef. 79.82 7.51 4.69 7.53 13 50 140.9 g (99%) 117.4 g C₆₂H₆₇ClN₄ (903.7) Ber. C. 82.40% H 4.74% Cl 3.92% N 6.20% Gef. 82.61 7.31 3.70 6.39 14 75 182.4 g (99.5%) 150 g C₇₆H₇₉ClN₄ (1083.9) Ber. C. 84.21% H 7.35% Cl 3.27% N 5.17% Gef. 84.40 7.23 3.12 5.31

Example 15

If 378.6 g (2 mol) of tetraethylene pentamine are used instead of triethylene tetramine according to Example 11, 110.8 g (99.5% of theory) of a sticky, brownish, water-soluble resin (hydrochloride) or 95.5 g of the corresponding one is obtained Amine base.
Hydrochloride C₃₆H₄₈ClN₅ (586.3) Ber. C. 73.75% H 8.25% Cl 6.05% N 11.95 Gef. 73.93 8.11 5.89 11.78

In the examples below, the procedure is analogous to that in example 15, with benzyl chloride condensation rates being varied. E.g. % Separation HCl Benzyl resin polyamine.HCl free base 16 50 150.1 g ( ^∼ 100%) 128 g C₆₄H₇₂ClN₅ (946.8) Ber. C. 81.19% H 7.67% Cl 3.75% N 7.40% Gef. 81.32 7.51 3.65 7.51 17th 75 185.7 g (94.6%) 165.1 g C₇₈H₈₄ClN₅ (1127.03) Ber. C. 83.13% H 7.51% Cl 3.15% N 6.22% Gef. 83.21 7.43 3.07 6.34

Example 18

Using the same procedure as in Example 11, using 102 g (1 mol) of N, N-dimethyl-1,3-propylenediamine instead of triethylenetetramine gives 80.5 g (91.9% of theory) of a greenish, sticky resin ( free base).
C₃₃H₃₈N₂ (462.7) Ber. C. 85.67% H 8.28% N 6.06% Gef. 85.79 8.13 6.01

The following examples are carried out analogously to Example 18, with a variation in the degree of benzyl resin condensation: E.g. % Separation HCl Benzyl resin polyamine (free base) 19th 33 97.6 g (97.2% of theory) C₄₇H₅₀N₂ (642.9) Ber. C. 87.80% H 7.84% N 4.36% Gef. 87.97 7.71 4.21 20th 50 111 g (96.4% of theory) C₆₁H₆₂N₂ (823.2) Ber. C. 89.00 H 7.5759 N 3.40 Gef. 89.12 7.45 3.32

Example 21

Analogously to Example 11, 2 moles of benzyl chloride are condensed to give 25% HCl and excess benzyl chloride is removed in vacuo. 206 g (2 mol) of diethylene triamine are then stirred into the resinous, viscous residue in one pour at room temperature. The gradually starting exothermic reaction is completed by heating to 110 ° C. After 2 hours at this temperature, excess amine is distilled off in vacuo to a bottom temperature of 100 ° C. and 105 g (99.2% of theory) of a honey-colored, viscous resin (hydrochloride) are obtained, which is soluble in water with a soapy consistency .
C₃₂H₃₈ClN₃ (500.1) Ber. C. 76.85% H 7.66% Cl 7.09% N 8.40% Gef. 76.97 7.49 7.01 8.31

Example 22

If, analogously to Example 21, 292.4 g (2 mol) of triethylenetetramine are used instead of diethylene triamine, 113 g (98.3% of theory) of a honey-colored, viscous resin (hydrochloride) are obtained which form a 50% aqueous solution Can compound solution.
C₃₄H₄₃ClN₄ (543.2) Ber. C. 75.18% H 7.98% Cl 6.53% N 10.31% Gef. 75.29 7.87 6.38 10.20

The degree of benzyl resin condensation is varied in the following examples using the procedure according to Example 22: E.g. % Separation HCl Benzyl resin polyamine HCl 23 30th 112 g (98.2%) C₄₁H₄₉ClN₄ (633.3) Ber. C. 77.76% H 7.80% Cl 5.60% N 8.85% Gef. 77.89 7.69 5.48 8.77 24th 40 122 g (98.4%) C₅₅H₆₁ClN₄ (813.6) Ber. C. 81.20 H 7.56 Cl 4.36 N 6.89 Gef. 81.33 7.49 4.23 6.75 25th 50 140 g (93.3%) C₆₂H₆₇ClN₄ (903.7) Ber. C. 82.40 H 7.47 Cl 3.92 N 6.20 Gef. 82.52 7.35 3.80 6.11 26 60 149 g (94.2%) C₆₉H₇₃ClN (993.8) Ber. C. 83.39 H 7.40 Cl 3.57 N 5.64 Gef. 83.48 7.31 3.43 5.51

Example 27

189.3 g (1 mol) of tetraethylene pentamine are stirred into 47.5 g (0.075 mol) of the polybenzyl chloride resin according to Example 5, brought to 110 ° C. and kept at this temperature for 2 h. After removing the excess of amine in vacuo, 65 g (∼100% of theory) of one are obtained brownish, sticky resin (HCl form), which can be processed into an aqueous solution.
C₅₇H₆₆ClN₅ (856.65) Ber. C. 79.92% H 7.77% Cl 4.14 N 8.18% Gef. 80.04 7.61 4.01 8.10

Example 28

According to the procedure of Example 27, using 232.4 g (1 mol) of pentaethylene hexamine gives 67 g (99.3% of theory) of a yellow-brown, viscous resin.
C₅₉H₇₁ClN₆ (899.7) Ber. C. 78.76% H 7.95% Cl 3.94% N 9.34% Gef. 78.89 7.83 3.83 9.27

Example 29

∼C₄₁H₆₂Cl₂N₈ (737,9) Ber. C 66,74% H 8,47% Cl 9,61% N 15,19% Gef. 66,86 8,35 9,50 15,06 Analogously to Example 11, 126.6 g (1 mol) of benzyl chloride, 26.3 g (0.15 mol) of o-xylylene chloride and 0.15 g of Zn-stearate are co-condensed with 25% elimination of HCl and after removal of excess monomers in Vacuum the resinous residue (59.0 g; 15% saponifiable Cl) with 73.1 g (0.5 mol) of triethylene tetramine. 93.5 g (∼100% of theory) of a sticky, viscous resin are obtained, which can be compounded into a 50% aqueous solution (idealized formula):

∼C₄₁H₆₂Cl₂N₈ (737.9) Ber. C. 66.74% H 8.47% Cl 9.61% N 15.19% Gef. 66.86 8.35 9.50 15.06

Example 30

126.6 g (1 mol) of benzyl chloride and 0.1 g of Zn stearate are condensed analogously to Example 8 with 50% elimination of HCl, the reaction is stopped by adding 2-3 drops of triethylene tetramine, then - without removing the excess benzyl chloride - 14.6 g (0.1 mol) of triethylenetetramine were added dropwise at 100 ° C. in the course of 30 minutes. The mixture is stirred for 30 minutes at this temperature, 100 ml of toluene and a solution of 20 g (0.5 mol) of NaOH in 50 ml of water are added and the mixture is kept under reflux for 3 hours. After cooling, the organic phase is separated off, washed with water and concentrated in vacuo to a bottom temperature of approximately 150 ° C.: 99.8 g (95.3% of theory) of a brownish, viscous, non-water-soluble resin.
C₇₆H₇₈N₄ (1047.5) Ber. C. 87.15% H 7.51% N 5.35% Gef. 87.29 7.43 5.19

In the following examples, one varies accordingly by varying the degree of polybenzyl condensation: E.g. % Separation HCl Resin (free base) 31 30th 101, g (96.5% of theory) Gef. C. 87.20 H 7.39 N 5.21 32 40 100.5 g (95.9% of theory) Gef. C. 87.31 H 7.63 N 5.15

Example 33

Analogously to Example 30, 126.6 g (1 mol) of benzyl chloride, 0.15 g of Zn stearate (30% HCl elimination), 18.9 g (0.1 mol) of tetraethylene pentamine and 28 g (0.7 mol) of caustic soda implemented with each other. 107.8 g (98.8% of theory) of a brownish viscous resin are obtained.
C₇₈H₈₃N₅ (1090.6) Ber. C. 85.91% H 7.67% N 6.42% Gef. 86.09 7.53 6.30

Example 34

"C₇₄H₇₆N₄ (1021,5)" Ber. C 87,02% H 7,50% N 5,49% Gef. 87,23 7,32 5,61 Using the same procedure as in Example 33, 98.5 g (96.4% of theory) of a brownish, viscous oil are obtained using 12 g (0.2 mol) of ethylenediamine instead of tetraethylene pentamine.

"C₇₄H₇₆N₄ (1021.5)" Ber. C. 87.02% H 7.50% N 5.49% Gef. 87.23 7.32 5.61

Example 35

253.2 g (2 mol) of benzyl chloride and 0.3 g of Zn stearate are condensed analogously to Example 11 with 30% elimination of HCl, the reaction is stopped with 2-3 drops of diethylenetriamine, then the benzyl chloride mixture is stirred into a mixture of 62 g ( 0.6 mol) of diethylene triamine, 64 g (1.6 mol) of caustic soda, 150 ml of H₂O and 100 ml of toluene were added dropwise at 60-95 ° C. within 1 h. The mixture is kept at the reflux temperature for 3 h, the organic phase is separated off and concentrated in vacuo to a bottom temperature of 150 ° C.: 235 g (97% of theory) of an orange-brownish, viscous oil.
"C₈₂H₉₉N₉ (1210.8)" Ber. C. 81.35% H 8.24% N 10.41% Gef. 81.57 8.19 10.63

Example 36

According to Example 35, using 82.6 g (0.8 mol) of diethylenetriamine gives 249 g (94.8% of theory) of a light brown, viscous oil.
"C₈₆H₁₁₂N₁₂ (1313.9)" Ber. C. 78.62% H 8.59% N 12.79% Gef. 78.85 8.67 12.52

Furthermore, following the procedure of Examples 35 and 36, the following - partially benzylated - polyamines are obtained as yellowish, viscous oils when uncondensed benzyl chloride is used: E.g. Amine Benzyl chloride NaOH Polybenzylamine 37 Triethylene tetramine 4 moles 4 moles 496 g (97.9% of theory) C₃₄H₄₂N₄ (506.7) Ber. C. 80.59% H 8.36% N 11.06% Gef. 80.72 8.47 10.89 38 Bis (3-aminopropyl) amine 3 moles 3 moles 394 g (98.1% of theory) C₂₇H₃₅N₃ (401.6) Ber. C. 80.75% H 8.78% N 10.46% Gef. 80.56 8.67 10.31 39 Pentaethylene hexamine 4 moles 4 moles 585 g (98.7% of theory) C₃₈H₅₂N₆ (592.9) Ber. C. 76.99% H 8.84% N 14.18% Gef. 77.13 8.69 13.98

Examples of use Example 40 Testing the corrosion-inhibiting effect in hydrochloric acid (acidizing)

The tests were carried out under the following conditions: The corrosion inhibitor is dissolved or dispersed in hydrochloric acid, if appropriate in combination with an acetylene alcohol. It is advisable to prepare a formulation beforehand from a solvent that is miscible with water or hydrochloric acid and a surfactant. Preferred solvents are lower alcohols, ketones or glycols, and also dimethylformamide, formamide, acetonitrile, N-methylpyrrolidone. A degreased steel coupon is placed in the hydrochloric acid. After 6 hours, the weight loss of the coupon is determined and converted into a surface removal rate.

Table 1:

Temperature: 70 ° C
Pressure 1 bar
Steel grade K 50 Table 1 (acidizing inhibitors) Connection according to example Concentr. [ppm] Concentr. Propargyl alcohol [ppm] Acid strength [%] Removal [µm / h] 21st 670 500 15 0.139 22 670 500 15 0.247 27th 670 500 15 0.193 28 670 500 15 0.404 31 670 500 15 0.049 31 670 500 30th 0.181 32 670 500 15 0.050 32 670 500 30th 0.127 33 670 500 15 0.056 37 670 500 15 0.097 37 670 500 30th 5,323 38 670 500 15 0.172 39 670 500 15 0.210 comparison - 500 15 0.135 30th Coupon released after 1 h

Example 41 (Refinery inhibitors)

A 2 l two-necked flask is equipped with a 400 ml Soxhlet extractor and a reflux condenser. Another glass tube is placed between the extractor and the reflux condenser, into which dropping taps for the inhibitor solution are introduced. Two metal coupons made of ST 37 steel are hung in such a way that two are in the Soxhlet extractor, i.e. in the liquid phase, and two in the gas space below the dropping points for the inhibitor solution. The latter pair of coupons is placed so that the inhibitor solution drips directly onto the coupons.

About 1 l of a mixture of aromatic and aliphatic hydrocarbons, for example diesel, kerosene, gasoline or also artificially produced mixtures, 100 ml of H₂S-saturated water and 20 ml of 30% hydrochloric acid is now placed in the flask. It is heated and at the start of boiling the inhibitor solution is then added dropwise at a rate of approx. 0.4 ml per minute. The inhibitor solution is a hydrocarbon in which the active ingredient is dissolved at a concentration of 50-1000 ppm. The test run ends after about 4 hours, the coupons are evaluated gravimetrically and compared with the blank value.

Example 42 Testing as a corrosion inhibitor for copper

Bare and degreased copper samples were used for the corrosion test. Artificial seawater according to ASTM D665-IP135, to which the substance to be examined was added, served as the test solution. During the test period of 7.5 hours, the metal samples were completely immersed in the 55 ° C test solution, into which approx. 100 ml air / min was introduced.

wobei
m = Massenverlust der Metallprobe ohne Inhibitor (Blindprobe),
m₁ = Massenverlust der Metallprobe mit Inhibitor bedeuten.After the test, the samples were cleaned in semi-concentrated hydrochloric acid for 15 seconds and washed with water and acetone. The dry metal samples were weighed before and after the test. The protective potential S, based on a blank sample, was calculated from the loss of mass:

in which
m = loss of mass of the metal sample without inhibitor (blank sample),
m₁ = loss of mass of the metal sample with inhibitor.

The results of the percent protective effect are given in Table 3. Table 3 (Corrosion inhibitors for copper) Corrosion inhibitor Concentration in mg / l % Protective effect S without - 0 Liaison Ex. 9 50 91.3 "" 11 50 91.3 "" 12 50 78.9 "" 15 50 80.9 "" 16 50 82.9 "" 22 50 96.9 "" 23 50 96.0 "" 24 50 95.0 "" 25 50 81.9 Comparison: Pentaethylene hexamine 50 0 Bis (3-aminopropyl) amine 50 0

Example 43 Testing as a corrosion inhibitor for iron

Bare and degreased metal samples from unalloyed steel RST 14-03 according to DIN 1623 were left in corrosive water according to ASTM D1384-70 for 24 hours. Approx. 100 ml air / min was passed through the test solution, which contained the substance to be examined. The test temperature was 20 ° C. The pH of the test solution was 7-8 and, if necessary, was adjusted with dilute sodium hydroxide solution or dilute sulfuric acid.

After the test, the metal samples were cleaned in semi-concentrated hydrochloric acid for 15 seconds and washed with water and acetone. The dry metal samples were weighed before and after the test. The percentage protective effect S, based on a blank sample, was calculated from the loss of mass. The results are shown in Table 4. Table 4 (Corrosion inhibitors for iron) Corrosion inhibitor Concentration in mg / l % Protective effect S without - 0 Liaison Ex. 11 500 91.3 "" 21 500 97.6 "" 22 500 97.2 "" 23 500 88.1 "" 24 500 96.7 "" 25 500 92.6 "" 26 500 95.6 "" 28th 500 93.5

Example 44 Testing as a corrosion inhibitor in acids

The mass losses of samples from unalloyed steel RST 14-03 in 10% hydrochloric acid and in 10% sulfuric acid were determined. The temperature of the acid was 50 ° C, the test time 3 hours.

By comparing the mass losses in acids with and without inhibitor, the percentage protective action S was calculated according to the equation given in Example 42. The results are shown in Tables 5 and 6. Table 5 (Corrosion inhibitors in hydrochloric acid) Test solution: 10% HCl Corrosion inhibitor Concentration in% by weight % Protective effect S without - 0 Liaison Example 9 0.05 98.0 "" 10 " 96.6 "" 11 " 98.6 "" 12 " 98.3 "" 13 " 97.4 "" 14 " 91.0 "" 15 " 98.9 "" 16 " 98.6 "" 17th " 97.2 "" 18th " 98.1 "" 19th " 98.6 "" 20 " 97.6 "" 21 " 98.8 "" 22 " 98.0 "" 23 " 98.0 "" 24 " 97.6 "" 25 " 97.6 "" 26 " 97.0 "" 27 " 98.8 "" 28th " 97.6 "" 29 " 99.0 "" 30 " 99.5 "" 31 " 99.9 "" 32 " 99.9 "" 33 " 99.9 Corrosion inhibitor Concentration in% by weight % Protective effect S Liaison Example 34 0.05 99.6 "" 35 " 99.5 "" 36 " 99.5 "" 38 " 97.2 "" 39 " 97.5 Comparison: Ethylenediamine 0.05 39.6 Diethylene triamine " 47.8 Triethylene tetramine " 70.5 Tetraethylene pentamine " 78.0 Pentaethylene hexamine " 79.6 Bis (3-aminopropyl) amine " 53.0 Pentamethyl-diethylenetriamine " 38.6 (Corrosion inhibitors in sulfuric acid) Test solution: 10% H₂SO₄ Corrosion inhibitor Concentration in% by weight % Protective effect S without - 0 Liaison Example 11 0.05 89.6 "" 29 " 90.0 "" 32 " 87.0 "" 33 " 90.3 "" 36 " 87.0 "" 37 " 89.2 "" 38 " 98.7 "" 39 " 99.0

Claims (7)

1. Use of polyaralkylamines of the formula

wherein
R¹ to R⁴ are the same or different and are hydrogen, C₁-C₁₈ alkyl, C₅-C₁₂ cycloalkyl, C₇-C₁₈ aralkyl, poly-C₇-C₁₈ aralkyl having 2 to 50 aralkylene units or C₆-C₁₅ aryl or
R¹ to R⁴ are linked so that two of the radicals together with the nitrogen atom connecting them or with the NC-containing chain form a 5- to 6-membered ring, at least one of the radicals R¹ to R⁴ C₇-C₁₈-aralkyl or Poly-C₇-C₁₈ aralkyl means, and
R⁵ and R⁶ independently of one another are hydrogen, C₁-C₆-alkyl, C₅-C₇-cycloalkyl, C₇-C₁₂-aralkyl or C₆-C₁₀-aryl,
m represents an integer from 2 to 10 and
n means 0 to 30,
where, if n = 0, at least one of the radicals R¹, R² and R⁴ is polyaralkyl, the radical R⁵ and R⁶ defined with m and the CN chain defined by n can have different values for m,
as corrosion inhibitors for metallic materials. 2. Use of polyaralkylamines as corrosion inhibitors for metallic materials according to claim 1, characterized in that the polyaralkylamines are used in an amount of 0.001 to 3% by weight, based on the corrosive medium. 3. New polyaralkylamines of the formula

wherein
R⁷ to R¹⁰ are the same or different and are hydrogen, C₁-C₁₈-alkyl, C₅-C₁₂-cycloalkyl, C₇-C₁₈-aralkyl, poly-C₇-C₁₈-aralkyl with 2 to 50 aralkylene units or C₆-C₁₅-aryl or
R⁷ to R¹⁰ are linked to one another in such a way that two of the radicals together with the nitrogen atom connecting them or with the NC-containing residual chain form a 5- to 7-membered ring, at least one of the radicals R⁷ to R¹₈ poly-C₇-C₁₈- aralkyl means 2 to 50 aralkylene units,
R⁵ and R⁶ independently of one another are hydrogen, C₁-C₆-alkyl, C₅-C₇-cycloalkyl, C₇-C₁₂-aralkyl or C₆-C₁₀-aryl,
m represents an integer from 2 to 10 and
n means 0 to 30,
where the C chain defined with m different residues R⁵ and R⁶ and the CN chain defined by n can have different values for m. 4. Process for the preparation of new polyaralkylamines of the formula

wherein
R⁷ to R¹⁰ are the same or different and are hydrogen, C₁-C₁₈-alkyl, C₅-C₁₂-cycloalkyl, C₇-C₁₈-aralkyl, poly-C₇-C₁₈-aralkyl with 2 to 50 aralkylene units or C₆-C₁₅-aryl or
R⁷ to R¹⁰ are linked to one another in such a way that two of the radicals together with the nitrogen atom connecting them or with the NC-containing residual chain form a 5- to 7-membered ring, at least one of the radicals R⁷ to R¹₈ poly-C₇-C₁₈- aralkyl means 2 to 50 aralkylene units,
R⁵ and R⁶ independently of one another are hydrogen, C₁-C₆-alkyl, C₅-C₇-cycloalkyl, C₇-C₁₂-aralkyl or C₆-C₁₀-aryl,
m represents an integer from 2 to 10 and
n means 0 to 30,
where the C chain defined by m can have different radicals R⁵ and R⁶ and the CN chain defined by n can have different values for m,
characterized in that amines of the formula

wherein
R¹¹ to R¹⁴ are the same or different and are hydrogen, C₁-C₁₈ alkyl, C₅-C₁₂ cycloalkyl, C₇-C₁₈ aralkyl or C₆-C₁₅ aryl or
R¹¹ to R¹⁴ are linked together so that two of the radicals together with the nitrogen atom connecting them or form a 5- to 7-membered ring with the NC-containing radical chain, at least one of the radicals R¹¹ to R¹⁴ being hydrogen, and
R⁵, R⁶, m and n have the meaning given above,
with poly-C₇-C₁₈ aralkyl halides of the formula

wherein
R¹⁵ represents hydrogen, halogen, C₁-C₄-alkoxy or C₁-C₆-alkyl,
R¹⁶ and R¹⁷ are the same or different and are hydrogen or C₁-C₆-alkyl,
p represents an integer from 2 to 50 and
X represents halogen,
optionally together with mono-C₇-C₁₈ aralkyl halides of the formula

wherein
R¹⁵ to R¹⁷ and X have the meaning given above and
p 1 means
implements. 5. The method according to claim 4, characterized in that the amines are reacted in an at least stoichiometric ratio with the aralkyl halides. 6. Process according to Claims 4 and 5, characterized in that the reaction is carried out at -20 ° C to 200 ° C. 7. Process for the preparation of poly-C₇-C₁₈ aralkyl halides of the formula

wherein
R¹⁵ represents hydrogen, halogen, C₁-C₄-alkoxy or C₁-C₆-alkyl,
R¹⁶ and R¹⁷ are the same or different and are hydrogen or C₁-C₆-alkyl,
p represents an integer from 2 to 50 and
X represents halogen,
characterized in that mono-C₇-C₁₈ aralkyl halides of the formula

wherein
R¹⁵ to R¹⁷ and X have the meaning given above and
p 1 means
condensed in the presence of condensing agents up to a conversion of 5 to 70 mol% of the amount of hydrogen halide which can be eliminated and, if appropriate, the unreacted amount of starting product is separated off.