CH628334A5 - Process for the preparation of aromatic uretdione diisocyanate disulphonic acids, and the use thereof - Google Patents

Description

628 334

2nd

PATENT CLAIMS 1. Process for the production of aromatic uretdione diiso cyanate disulfonic acids.

R

£ "5

0

II

c

SO ^ H R

0Cliî ~ ^ / (x) n \ 2ì ^ /

SCUH 5

0

wherein

Rj, R2, R3, R4, R5, R6 represent hydrogen, chlorine, bromine, methyl, ethyl or Cr to C4-alkoxy,

15

Compounds of formula I obtained for the production of polyurethane plastics as reactants of polyols. v I 4. Use of the according to the method of claim 1

x denotes -O-, ^ C = S02, Rt-C-R8 or -CH = CH-, compounds of the formula I obtained for the preparation of wherein '20 polyureas as reactants of polyamines.

R7 and R8 for hydrogen, methyl, ethyl or together 5. Use of the according to the method of claim 1

stand with the carbon atom for cyclohexylidene, and compounds of the formula I obtained for the preparation of Po tt 0 or 1, characterized in that a diisurethane polyureas as reactants of polyols cyanate of the formula and polyamines.

25th

The present invention relates to the production of aromatic Rp R1 shear uretdione diisocyanate disulfonic acids and their uses.

¥ 'x / dung as a structural component in the production of polyurethane

/ f \\ 30 than plastics.

(x) "«)} - NCO Aromatic diisocyanates with sulfonic acid groups are

\ / knows (DT-OS1 939 911). By reaction of tolylene diiso-

_ cyanate and sulfur trioxide, for example,

Installed high-melting product which dissolves in sodium hydroxide solution with rapid reaction and which can be used, for example, for the preparation of anionic PU dispersions. From DT-OS 2 227 111 it is also known that sulfur trioxide is used in anhydrous solvents which are inert towards S03 and isocy- sulfonic acid and / or sulfonate groups and polyisocyanate groups in the temperature range from 4Q anate, which, in addition to other reaction products, also converts uretdione at -30 ° C. to +100 ° C. Derivatives by sulfonation of liquid More-

2. The method according to claim 1, characterized in that component mixtures of aromatic polyisocyanates are obtained so that the reaction can be carried out with gas diluted by inert gas (cf. also DT-OSS 2 359 614 and 2 359 615). moderate S03. It has now been found that aromatic 4-core

3. Use of the general formula in which by the method according to claim 1 ^ uretdione diisocyanate disulfonic acids

Rb R2, R3j R4, R5 and R6 represents a hydrogen, chlorine or bromine atom, a methyl, ethyl or Ci-C4-alkoxy group,

is obtained if a particularly solid diisocyanate of the general formula

60

x represents -O-, C = 0, S02, Rt-C-R8 or -CH = CH-, where '

R7 and R8 represent a hydrogen atom, a methyl, ethyl or 65 together with the carbon atom a cyclohexylidene group, and n represents 0 or 1, generally as a crystallized powder

\ / 5

OCN

* - \ Q / ~ (Oy

NCO

3rd

in which R1; R2, R3, R4, R5, Ré, n and x have the meaning given above, sulfonated with sulfur trioxide in an anhydrous solvent which is inert to S03 and isocyanate groups in the temperature range from - 30 ° C to +100 ° C.

The compounds obtained are new. 5

Finally, the present invention also relates to the use of the new uretdione-diisocyanate-dis-sulfonic acids mentioned as a reaction partner for compounds having groups which are reactive toward isocyanate groups, in which, in the production of polyurethane plastics, 10 Rb R2, R3, R4, R5, Rg, n and x are the known isocyanate polyaddition processes mentioned above. Have meaning.

It is extraordinarily surprising that, in the case of the starting compounds preferred according to the invention, diisocyanates of the processes according to the invention quantitatively form uretdione in the formula mentioned, in which R 1 and R 4 for hydrogen or a medium take place under sulfonation conditions, since the bis- a methyl group, R 2, R3, R5 and R6 for hydrogen, x for known isocyanate dimerizations according to literature (High 15 is a methylene bridge and n is 1.

Polymers, Vol. XVI, “Polyurethanes, Chemistry and Tedinolo- Examples of such diisocyanates are 4,4'-diisocyanatodi-

gy », written by Saunders-Frisch, Interscience Publishers, New phenylmethane, 3,3'- or 2,2'-dimethyl-4,4'-diisocyanatodi-York, London, volume 1,1962, page 91) under basic Reactphenylmethane, 2,5,2 ', 5'-tetramethyl-4,4'-diisocyanatodiphention conditions or specific phosphine catalysis in front of nylmethane, 3,3'-Dimethoxy-4,4'-düsocyanato-diphenylmethane, go. It is also noteworthy that starting from diisocy- 20 3,3'-dichloro-4,4'-diisocyanato-diphenylmethane, 4,4'-diisocyanates, defined diisoanato-diphenyldimethylmethane containing a uretdione ring, Form 4,4'-diisocyanato-benzophe-cyanate disulfonic acids and no higher molecular weight polyons, 4,4'-diisocyanato-diphenyl sulfone, 4,4'-diisocyanato-di-lyuretdiones, such as those obtained from corresponding diisocyanates under phenyl ether, 4'-Diisocyanato-3,3'-dibromo-diphenylmethane, phosphine catalysis arise. As can be seen from NMR spectroscopic 4,4'-diisocyanato-3,3'-diethyl-diphenylmethane, 4,4'-diisocyte studies (see exemplary embodiments), 2S anato-diphenyl-ethylene- (1,2).

the sulfonic acid groups in the compounds according to the invention. The solvents in question must be chemically inert both against the exclusively ortho position to the NCO groups, the reaction conditions compared to S03 and with respect to the diisocyanates under the uretdione group in the products according to the invention. Ha-are preferred. As a result, only two of the total logenated or nitrated hydrocarbons, e.g. Dichloro-four aromatic nuclei selectively sulfonated. Overall, the ethane, tetrachloroethane, methylene chloride, chloroform, Fhiortri method according to the invention is surprising, since in a re-chloromethane, nitromethane, nitrobenzene or ether, such as e.g. tion stage simultaneous selective sulfonation on one of the dioxane, THF or pyridine or also sulfur dioxide, the aromatic nuclei and selective dimerization of the subsequent reaction. The reaction is preferably carried out in a molar ratio of diiso-

independent NCO group. cyanate / S03 such as 1: 1 to 1: 1.4. One can also

35 use a higher excess of S03, without the re-off of DT-OS 2 227 111, it was already known that the course of the action would change significantly. You can also work with a deficiency S03 in the partial sulfonation of liquid aromatic polyisocyanates and recover the unreacted diisocyanate to liquid, unspecified, sulfonic acid groups or, in a continuous procedure, also recycle uretdione groups in the polyisocyanates containing them.

which can be seen in the IR spectrum. The process according to the invention is carried out at temperatures between -30.degree. C. and +100.degree. C., preferably -10.degree. C. It could not be deduced from this, however, that at + 30.degree. C., particularly preferably -5.degree. C. and +10.degree -stoichiometric sulfonation of a 4,4'-diisocyanate-2 leads. In this case, the diisocyanate in anhydrous core aromatics is preferably submitted to a defined uretdione sulfonic acid, which is used in a nitrogen stream. 45 steamed SO 3 was passed onto the surface of the well-stirred mixture, the temperature preferably being maintained by cooling. Remarkably, even during the sulfonation of 4,4'-within the preferred ranges mentioned, it is maintained. Diisocyanatodiphenylmethane, a compound that is known- The uretdiones according to the invention fall as white or pink compounds containing two NCO groups of the same and pronounced reak-colored, insoluble, solid and active in organic solvents, practically exclusively the mono-uretdione-50- preferably in powder form crystalline products. You found besit sulfonic acid. The thermodynamically possible zen generally have no melting point and go smoothly into dimerization of a sulfonated diisocyanate with a non-dilute alkali with decomposition in solution. Even sulfonated diisocyanate does not occur. The second, an NCO combination of a solution of the starting dansocyanate and a group-bearing aromatic nucleus, is neither sulfonated nor a solution of SO 3 or its adducts can dimerize the sulfonation. 55 can be accomplished.

The sulfonation can be carried out with free S03 or with organic. The remaining mother liquors can be reused for further reac compounds in which S03 is additively bound.

closure of water. The S03 can react in liquid form as diisocyanates.

ger - or in gaseous, e.g. diluted with nitrogen - in accordance with the invention at elevated temperature, according to the known method. Diisocyanate polyaddition process, e.g. Glycols, poly

As organic compounds in which S03 additively bound, higher molecular weight polyols, e.g. Polyethers or the, preferably pyridine-S03, dioxane-S03, tetrahy polyesters, to the corresponding polyurethanes or poly-drofuran-S03, ether-S03, dimethylformamide-S03 may be mentioned. ureas or polyurethane polyureas. Due to the preferred method, however, the sulfonation is carried out using gaseous SO 3, diluted in 65% in each case with one sulfonic acid group per mole, using a nitrogen stream. cyanate, the isocyanato-uretdiones are practically completely non-toxic

Starting compounds for the process products according to the invention, which are also in the degradation of ren built therefrom, are the isocyanates of the formula polymers, again non-toxic substances (aminosulfonic acids)

628 334

4th

deliver. Furthermore, the products have no measurable vapor pressure. As a result, the isocyanato-uretdiones according to the invention are versatile as physiologically perfect diisocyanates, e.g. as structural components in the context of the di-socyanate polyaddition process, as a crosslinking agent, for the production of 5 polyisocyanurates, polycarbodiimides, polyimides or polyhydantoins. Owing to their strongly polar or ionic character, the uretdione diisocyanates according to the present invention are particularly suitable for the construction of water-soluble or water-dispersible polyurethanes and polyurethane ureas.

The uretdione diisocyanates are suitable as such and also in the form of their reaction products, for example for the production of binders and impregnating agents, in particular for inorganic or mineral substrates, and for the construction of 15 physically crosslinked ionomers, as well as cation exchangers and membranes. Furthermore, by mixing the uretdione diisocyanates according to the invention with compounds containing HO groups, plastisols which are stable in storage and which cure at temperatures above 100 ° C. can be produced. 20th

example 1

500 g (2 mol) of 4,4'-diisocyanatodiphenylmethane are dissolved in 1000 ml of 1,2-dichloroethane. An S03 / nitrogen stream is fed to the surface of this vigorously stirred solution at -5 to 5 ° C and is obtained by evaporation at 130 ° C from 101 ml (2.4 mol) of freshly distilled S03 in a stream of nitrogen. The amount of nitrogen is regulated

that no more S03 emerges from the reaction vessel. The mixture is stirred until the reaction mixture has warmed to room temperature, after which it is suctioned off.

This gives 470 g (yield: 71% of theory) of the uret-dione and that only 1 core of the starting diisocyanate has been sulfonated.

Example2

69.5 g ('A mol) of 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane are dissolved in 300 ml of 1,2-dichloroethane analogously to the procedure given in Example 1 with 11 ml (-' A mol ) S03 implemented.

The uretdione derivative is obtained

OCN

as a pink colored powder; Yield: 50% of theory; Mp> 280 ° C under decomp.

Analysis:

calculated:

found:

c%

H %

N%

0%

S%

57.0

3.9

7.8

22.3

9.0

56.2

4.2

7.2

22.6

9.5

OCN

as a pink colored powder. Mp> 280 ° C under decomp.

Analysis: C% H% N% 0% S%

calculated: 54.5 3.0 8.5 24.3 9.7 found: 53.8 3.4 8.6 23.9 10.1

45

IR spectrum: 2280 cm-1 (intense) —NCO band

1170 cm ~ 1 - (intensive) urtdione band 1185 cm-1 -S03H band.

The position of the uretdione band at 1770 cm-1 corresponds very well to the shift of the uretdione band by the ortho-standing sulfonic acid group discussed in Example 1, in the present case this band shift is partially compensated for by the ortho-standing methyl group which is also present.

NMR spectrum: signals between 6.80 and 7.60 ppm: aromatic protons;

Integration: 5 proton signal at 3.60 ppm: CH2 group; Integration: 2 proton signal at 2.10 ppm: CH3 groups; Integration: 6 protons

Example 3

69.5 g of QU mol) of 4,4'-diisocyanato-dimethyl-diphenyl-methane dissolved in 300 ml of 1,2-dichloroethane are sulfonated with 14 ml (0.33 mol) of SO3 by the same method described in Example 1. The precipitated white powder is the uretdione derivative

IR spectrum: 2275 cm "1 (intense) —NCO band 50

1790 cm-1 (intense and wide) -retention band 1180 cm-1 (wide) -S03H band

The IR band at 1790 cm-1 proves the presence of a S03H group ortho to the uretdione group, since 55 the uretdione band in ortho unsubstituted uretdions is normally around 1765 cm-1. The stated constitution was also corroborated by NMR spectroscopic investigations: by treatment with deuterated dilute alkali, the reaction product, under the development of CO 2, goes into solution. The sulfanilic acid derivative formed under these conditions has between 6.75 and 7.50 ppm a characteristic aromatic proton resonance spectrum for structures containing 1,2,4-ti-substituted benzene rings. The ratio between the aromatic protons and the aliphatic -CH2 protons determined by integrating the signals is 7/2. This proves that the -S03H substituents are ortho to the uretdione group

? H3

OCN - <0) -? ~ OK.

dar; Yield: 33% of theory; Mp> 285 ° C with decomposition. When the solvent is concentrated, a solid residue remains, which consists of the starting diisocyanate and other uretdione derivative.

Example 4

126 g ('A mol) of 4,4'-diisocyanatodiphenyl ether are reacted in 400 ml of 1,2-dichloroethane according to the procedure given in Example 1 with 21 ml (' A mol) of SO3 at 50 ° C. The partly precipitated slightly yellow colored powder (mp.>

628 334

280 ° C with decomp.) And the residue after the dichloroethane evaporation consist mainly of the uretdione derivative:

Treated diisocyanato-diphenylmethane in 300 ml of 1,2-dichloroethane with 11 ml of freshly distilled S03. After concentration of the solvent, the desired uretdione derivative

OCN

Example 5

According to the same procedure described in Example 1, but at 25-30 ° C, 80 g (Vj mol) of 3,3'-dichloro-4,4 '-

10th

15

0

[- Cl OCN

Cl

^)> - ch; KO

N

_ /

so3H

mp> 280 ° C under decomp. won.

C.