DE1109889B - Process for the production of polyureas - Google Patents

Description

INTERNAT.KL. C 08 g

GERMAN

PATENT OFFICE

M37031IVb / 39c

REGISTRATION DATE: MARCH 17, 1958

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL: JUNE 29, 1961

The invention relates to a process for the production of polyureas, which optionally have cyclic radicals.

The invention aims to provide a process for the production of polyureas, which is disclosed in technically simple way using readily available reagents, under simple Reaction conditions and can be carried out with good yield.

It has been found that polyureas can be prepared by reacting carbon monoxide and sulfur with an organic compound having at least two —NH ₂ groups or an organic compound having at least one —NH ₂ group and at least one —NH group at elevated levels Temperature converts. Such compounds are referred to below as organic diamines. The position of the amino groups with respect to one another in the organic diamine determines the type of urea formed according to the invention.

In the case of aromatic organic diamines, polyureas are formed when the above Groups are attached to aromatic carbon atoms that are not adjacent to each other, z. B. are in the m or p position to each other.

In the case of aliphatic organic diamines, polyureas are formed when the above Groups attached to separate carbon atoms in the same chain, and these Carbon atoms are linearly separated from each other by more than 3 atoms.

According to the invention, carbon monoxide, sulfur and a compound with at least two NH ₂ groups or at least one —NH ₂ group and at least one —NH group are reacted at elevated temperature, with the —NH ₂ - or —NH groups are bonded to non-adjacent aromatic carbons and, in the case of aliphatic compounds, are bonded to different carbon atoms in the same chain which are linearly separated from one another by more than 3 atoms.

The reaction is preferably carried out at a temperature in the range from about 60 to 160 ° C and can optionally be carried out in the presence of an inert diluent.

The invention is explained in more detail below with the aid of a few examples.

example 1

In a 2-liter stainless steel autoclave, 108 g of m-phenylenediamine, 10.9 g of triethylamine, 64 g of Method of Preparation
of polyureas

Applicant:

Monsanto Chemical Company,
St. Louis, Mo. (V. St. A.)

Representative: Dr. E. Wiegand, Munich 15,

and Dipl.-Ing. W. Niemann,
Hamburg 1, Ballindamm 26, patent attorneys

Claimed priority:
V. St. v. America March 18, 1957

Fred Applegath and Raymond Amend Franz,

El Dorado, Ark. (V. St. A.) ₅
have been named as inventors

Introduced sulfur and an amount of CO sufficient to bring the autoclave to a pressure of 31.6 kg / cm ² . ^{The autoclave was heated to 120 °} C. for 4 hours while stirring. The contents were then taken out and unreacted amine extracted with hot methanol. A yield of 18% of poly-m-phenylene urea with a melting point above 300 ^° C. was obtained. The repeating unit of the polymer is represented by the following formula:

Example 2

A 1.8-1 stainless steel bomb was charged with 13.8 grams of 2,4,6-triaminotoluene, 9.7 grams of sulfur, 450 ml of methanol, and an amount of CO sufficient to pressurize the bomb to Bring 7 kg / cm ^a. The reaction was carried out at 115 ° C for 3V for _{2 hours.} The contents of the bomb would be evaporated to about 200 ml to remove the polymer

109 619/465

felling. A yield of 26% of a crosslinked (querverketteten) polymer having a melting point of 310 ⁰ C obtained.

Example 3

-Ν— '

Example 5

The procedure according to Example 4 was repeated, 32.4 g of p-tolidine, 9.76 g of sulfur, 54.2 g of triethylamine and an amount of CO being used which was sufficient ^{to generate a pressure of 7 kg / cm 2.} The reaction was carried out at 115 ^° C. for ^{3 ×} / _{2 hours.} A yield of 54% (14.5 g) of poly-4,4'- (3,3'-dimethylbiphenylene) urea with a melting point above 300 ^° C. was obtained. The repeating unit of this polymer is represented by the following formula:

CH ₃

H-C

N—

H ii
—Ν —C-

115 ° C. A yield of 10% (3 g) of poly-m- (4-methylphenylene) urea with a decomposition point above 300 ^° C. was obtained. The repeating unit of this polymer is represented by the following formula:

Into a 1-1 autoclave were placed 30 g of 2,4-diaminophenol hydrochloride, 9.76 g of sulfur, 54.2 g of triethylamine and an amount of CO sufficient to give a pressure of 7 kg / cm ² . The autoclave was heated to 115 ° C for _{3V 2 hours.} The polymer was washed with benzene, water and dilute HCl, and a yield of 72% (24.5 g) of poly-m- (4-oxyphenylene) urea was obtained. The repeating unit of this polymer is represented by the following formula:

Example 4

Into a 1-1 autoclave were placed 28.2 g benzidine, 9.76 g sulfur, 54.2 g triethylamine and a sufficient amount of CO ² to give a pressure of 7 kg / cm 2. The mixture was kept at 115 ^° C. for _{3 V for 2 hours.} The product was washed with dilute HCl and an Na ₂ S-Na OH solution, and a yield of 46% (14.6 g) of poly-p, p'-biphenyleneurea with a melting point above 30O ⁰ C was obtained. The repeating unit of this polymer is represented by the following formula:

40

45

60

Example 6

The procedure of Example 4 was repeated, using 30 g of 2,4-diaminotoluene, 24 g of sulfur, 2.5 g of triethylamine, 150 ml of methanol and an amount of CO sufficient ^{for a pressure of 21 kg / cm 2.} The reaction was at 3V for ₂ hours

Example 7

The procedure of Example 4 was repeated, using 25 g of o-dianisidine, 9.8 g of sulfur, 54.2 g of triethylamine and an amount of CO which was sufficient ^{for a pressure of 17.6 kg / cm 2.} The reaction was carried out at 115 ° C for 3 hours. A yield of 11% (3.0 g) of poly-4,4 '- (3,3'-dimethoxybiphenylene) urea with a decomposition point of 230 ° C. was obtained. The repeating unit of this polymer is represented by the following formula:

₃₅

Example 8

The same general procedure was followed as in Example 4 using a 2-1 Parr bomb and 88 grams of bis-3- (aminopropyl) ether, 21.2 grams of sulfur, 400 ml of methanol, and an amount of CO. which was sufficient for a pressure of 49.2 kg / cm ^2. The reaction was carried out at 120 ^° C. for 4 hours. There was obtained a yield of 100% (105 g) of poly (ditrimethylenoxy) urea having a melting point 191-193 ⁰ C. As determined from the specific viscosity of a 1 g sample of the polymer in 100 ml of 95% H ₂ SO ₄ at 25 ° C., the polymer had a degree of polymerization of 20. The repeating unit of this polymer is represented by the following formula :

f H H °)

\ _N — CH ₂ CH ₂ CH ₂ OCH ₂ CH ₂ Ch ₂ -NC- /

55

Example 9

486 g of p-phenylenediamine, 432 g of sulfur, 271 g of triethylamine, 900 ml of pyridine and an amount of CO sufficient ^{to generate a pressure of 35.2 kg / cm 2 were placed in a 7.5 l autoclave.} The reaction was carried out at 118 ° C for 2 hours. The reaction product was then _{washed twice with CS 3} and once with a concentrated Na ₂ S solution and then _{refluxed with a concentrated Na 2} S solution. The polymer was then washed twice with water and dried. A yield of 100% (600 g) of poly-p-phenyleneurea with a poly

degree of merization of 14 and a molecular weight of 1876. The repeating unit this polymer is represented by the following formula:

Example 10

The following polyureas were used in a

100 ml bomb made. In each case, 0.017 mol of diamine, 0.017 mol of sulfur, 20 ml of methanol and an amount of CO sufficient to ^{generate a pressure of 35.1 kg / cm 2 were used.}

The results are given in the table below. The degree of polymerization (DPn) was from the specific viscosity of 1 g of the polymer

ίο determined in 100 ml of 95% H ₂ SO ₄ at 25 ° C.

Diamine React
functional
tempe-
rature in
⁰ C Reak
tion time
in
hours Polymer produced yield
° / o DPn Softening
point in ⁰ C Hexamethylenediamine
Hexamethylenediamine
Hexamethylenediamine
Octamethylene diamine
Decamethylenediamine
Dodecamethylene diamine 120
140
160
160
160
160 4th
2
1
1
1
1 Polyhexamethylene urea
Polyhexamethylene urea
Polyhexamethylene urea
Polyoctamethylene urea
Polydecamethylene urea
Polydodecamethylene urea 73
59
49
71
80
83 22nd
30th
6th
12th
7th
6th 240 to 255
240
200 to 210

In addition to the diamines used in the preceding examples, organic diamines, the with one or more substituents (in addition to those already indicated) are substituted, the are not detrimentally reactive under the reaction conditions, in the reaction according to of the invention can be used. Under the expression »the under the reaction conditions not in harmful Wise reactive «are understood to mean groups that facilitate the formation of a desired Do not prevent polyurea. Such substituents are e.g. B. alkyl, aryl, cycloalkyl, alkenyl, Carboxy, oxy, thiol, cyano groups, halogen atoms including chlorine, bromine, fluorine and iodine atoms, Alkoxy, aryloxy, organosilyl, polysiloxanyl, alkylamino, dialkylamino groups or the like. Organic Diamines with 18 or more carbon atoms can be used. The molecular size of the organic diamine is not critical in this regard.

While not essential, in most cases it will be desirable to run the process in the presence of a run inert solvent or diluent. Aliphatic alcohols, especially methanol, are preferred for this purpose because they differ from the Polyurea e.g. B. easy to separate by evaporation and as they are solvents for many of the amines. Aromatic and aliphatic hydrocarbons, chlorinated hydrocarbons, ethers, tertiary amines and acid amides are also suitable. Water in and of itself is not a satisfactory diluent, albeit a minor one Amounts of water in the organic diluent can be tolerated. When a thinner is used, an amount sufficient to slurry the reagents is usually sufficient. Preferably, but not necessarily, a diluent in which the reagents are soluble is used. In the Manufacture of polyureas of the classes described should involve the use of oversized quantities of solvents should be avoided.

In addition to methanol, the following solvents or diluents can also be used: z. B. ligroin, isopropanol, isopropyl ether, ethanol, mineral oil, triethylamine, pyridine, isopropanol-water, ethylene glycol, glycol monomethyl ether, tetrahydrofurfuryl alcohol, Ν, Ν-dimethylaniline, N ₅ N-diethylethanolamine, formamide, amyl alcohol or benzene.

In general, the process does not require the addition of a catalyst. The reaction takes place in an alkaline medium. In most cases the amines used ensure sufficient alkalinity. When using aromatic diamines, an alkaline catalyst can be used to advantage, although this is not absolutely necessary. Alkaline catalysts with dissociation constants greater than 1 X 10 ^-10 are preferred. It should be noted, however, that an alkaline catalyst is desirable in making this type of polyurea. In the absence of an alkaline catalyst of the type described, the reaction is still going on; however, it gives lower yields.

Strong and weak inorganic bases appear to initiate the reaction alike, although the The resulting yields of polyurea are inferior to the preferred tertiary amine are. Inorganic hydroxides, alkaline inorganic and organic salts and tertiary aliphatic Amines can be used as catalysts. Tertiary alkyl amines are preferred.

The amount of catalyst to be added to help initiate the reaction depends depends on the selected connection. An amount from about 0.002 to about 0.2 moles of the alkaline Catalyst per mole of aromatic diamine is particularly beneficial, although considerably larger ones Amounts of catalyst as can be seen in the examples can be used.

The amounts of reagents that are used can vary significantly without that the scope of the invention is left. in the

in general, at least stoichiometric proportions of the reagents should be used. It can if desired, considerable excesses of one of the reagents can be used. The procedure has turned Proven to be particularly useful when considering molar ratios of organic diamine to sulfur used in the range 0.1: 1 to 8: 1. Even higher ratios can produce good results Application. In general, the particular ratio of reagents is made more economical Considerations as determined by responsiveness considerations.

The amount of carbon monoxide can be changed to a substantial extent; there can be an excess Be used above the stoichiometric ratio, the excess being primarily due the desired pressure is determined.

The process can be carried out over an exceptionally wide pressure range. It can be carried out at atmospheric pressure, although the reaction goes much faster at elevated pressure. In general, pressures from about 2 to about 100 kg / cm ² (abs.) Can be used. Higher pressures can also be used; however, they do not give any advantage.

The method can also be carried out within a wide temperature range. It is preferably carried out at an elevated temperature. Temperatures in the range from about 60 to about 300 ^° C. have proven to be applicable. In general, reaction temperatures in the range from about 60 to about 160 ^° C. are preferred, although these can be changed somewhat depending on the polyurea produced.

Claims (4)

PATENT CLAIMS: 1. A process for the preparation of polyureas, characterized in that carbon monoxide, sulfur and a compound having at least two - NH ₂ groups or at least one - NH ₂ group and at least one - NH group are reacted at elevated temperature, in the case of aromatic compounds which —NH ₂ or —NH groups are bonded to non-adjacent aromatic carbon atoms, and in the case of aliphatic compounds are bonded to different carbon atoms in the same chain which are linearly separated from one another by more than 3 atoms. 2. The method according to claim 1, characterized in that the reaction is carried out at a temperature in the range from about 60 to 160 ^c C. 3. The method according to claim 1 or 2, characterized in that the reaction in one inert diluent is run. 4. The method according to claim 3, characterized in that one carbon monoxide, sulfur and p-phenylenediamine, di-3- (aminopropyl) ether or hexamethylenediamine is implemented. Considered publications:
German patent specifications No. 745 684, 922 079. © 109 619/468 6.