DE1959462C3 - Substituted Diphenylmethanletraiso cyanate - Google Patents

Description

NCO

wherein R, an alkyl radical with 1 to 18 carbon atoms or a phenyl radical optionally substituted by alkyl radicals with I to 4 carbon atoms, halogen atoms or nitro groups and R ₂ denotes a hydrogen atom or a radical R, and in which R ₁ and R. 2 together a cycloaliphatic;) ring can form.
2; Tetraisöcyänat according to claim 1 of the formula

NCO

NCO

3. Tetraisöcyanat according to claim 1 of the formula

(CH ₃ J ₂ CH - CH

NCO

4. Tetraisöcyanat according to claim 1 of the formula

CH ₃

CH ₃ -CH - \\ - NCO NCO materials and a higher Itesliindigkcii the KIebunueii with Wiinneeiiiffekt. The use of this triisocyaiilcs is found in many fields. /. Significantly eingeschr.'inkl 13 in C \ ar leather and imitation leather manufacturing industry by the fact that Klubunjicn mil this Triisocyaniil. especially under the influence of light, discolor diinkly violet.

To avoid this disadvantage, according to the German patent 11 31 001 the use

, o of light-colored isocyanaloarylpliosphoric acid b / w. -thiophosphoric acid dci'ivalcn proposed. In the Practice has shown, however, that these or other proposed light-colored polyisocyanates do not the strength and durability of the bonds could be maintained with 4,4 ', 4 "-tnphynylmcthan-triisocyanate was to be achieved, This proved to be especially true when using the in practice, z. B. in the shoe industry for gluing rubber materials, very often used and therefore special important adhesives made of polychloroprene and door which have recently been used for gluing Polyvinyl chloride synthetic leathers have become practically indispensable and are used on a very large scale Solutions of hydroxyl polyurethanes.

It has now been found that they are considerably cheaper Adhesive results can be obtained as with all previously known polyisocyanates if one is used as an adhesive Solutions of natural or synthetic rubber, e.g. B. the known rubber or polyurethane binders, in combination with new substituted diphenylmethane tetraisocyanates of the general formula

OCN

NCO

NCO

NCO

wherein R _{1 is} an alkyl radical with 1 to 18 carbon atoms or a phenyl radical optionally substituted by alkyl radicals with 1 to 4 carbon atoms, halogen atoms or nitro groups and R _{2 is} a hydrogen atom or a radical R, and in which furthermore R ₁ and R ₂ together can form a cycloaliphatic ring is used.

The present invention thus relates to tetraisocyanates of the general formula

CH,

Polyisocyanates are already being used extensively in the adhesives field together with solutions used by polymers of very different types.

For example, solutions made from natural or synthetic rubber (including nitrile rubber, "Chloroprene rubber) solutions of 4,4 ', 4" -TriphenyImethan-triisocyanat and reached such a more favorable adhesion to many to be glued

OCN

NCO

NCO

NCO

in which R _{1 is} an alkyl radical having 1 to 18 carbon atoms or a phenyl radical optionally substituted by alkyl radicals having 1 to 1 carbon atoms, halogen atoms or nitro groups and R _{2 is} a hydrogen atom or a ReStR ₁ and in which R ₁ and R ₂ together are cycloaliphatic Can form a ring.

iRoeyjintitc this ArI are
associations:

ζ. IJ. the following advantages

CH ₃

OCN- / V C

CH,

NCO

/ V

NCO

NCO

1, R ₁ = CHj-R ₂ = H

2, R ₁ = (CH ₃ ), - CH-R ₂ = H

3, R ₁ = CH ₃ - (CH ₂ ) J-CH-C ₂ H ₅
R, = H

5. R ₁ = R ₂ = CH ₃ -

6. R ₁ + R ₂ =

7. R ₁ = CH ₃

R, =

or induivn vinyl donwiiun. HydrnXylpolyiiiliur. Hvdl'oxylpolyeslerinlui diiiiiiisliLTyeslulllW l'olynrcth.inu- ·. in Uclmchl. Preferred envelopes are polymerizing of chloroprene (2-C'hlorbiitiidien-1,3) odci produced with it Mixed polymer. especially about linear or largely linear mydroxy polyurene. those from lisleni iius ulipluilischcn or iiromaiischun Diwirbonsiiiircn and Alkiiiidiolen b / w. from l.adoncn. insbusondcrc Cupiolaelon. and aromatic or

ίο aliphatic f) iisucyunulcn. before iillem Toluylcnch-

isoeyanal, Diphcnylmc (hitndiisouynnal- (4,4 ') oder HexaiT) cihylenendiisoeyanat- (1,6) have been manufactured.

The ratio of polymer to calcium isocyanate

can vary within wide limits in the adhesives and be up to 1% by weight of polymer to 2% of the amount of tetrahydrofuran. The preferred weight ratio of polymer to tetra-isoeyanate, however, is between 100: 1 and 4: I.
As a solvent come for the adhesive

z. B. methylene chloride, trichlorethylene, methyl ethyl ketone or alhylacelate. To modify their adhesive properties, the Invention adhesives in addition to the binders mentioned, e.g. B. to achieve a particularly lasting Kontaktbindefühigkit or to increase the cohesive strength of the adhesive layer, even more Substances, including natural resins, modified natural resins (e.g. rosin ester) or synthetic Heaters (e.g. phthalal resins) or other polymers, ζ. Β. Chlorinated rubber or soluble polymers or copolymers of vinyl acetate or others Vinyl compounds, contain,

The parts or ratios given in the examples are parts by weight or weight ratio

nits.

The new tetraisocyanates can be prepared by generally known processes. So z. B. 2,4-tolylenediamine with various aldehydes or Ketones are condensed to the tetraaminodiphenylmethane derivative. The tetramine is in itself in a known manner reacted with phosgene to give the corresponding tetraisocyanate.

Of particular interest for the use according to the invention is 3,3'-dimethyltriphenylmethane-4,4 ', 6,6'-tetraisocyanate. This tetraisocyanate is not only particularly easily accessible from a preparative point of view, but can also be represented in a particularly high degree of purity, so that its solutions are almost completely colorless particularly suitable for bonding extremely sensitive materials.

Compared to the known polyisocyanates, in particular 4,4 ', 4 "-TriphenyImethanriisocyanat the excellent color stability of this tetraisocyanate according to the invention is also surprising. Although this tetraisocyanate is also a triphenylmethane derivative, it occurs no violet discoloration whatsoever when exposed to light.

As binders for the production of adhesives known polymers such. B. Natural rubber or synthetic rubber polymers, e.g. B. from dienes such as butadiene or copolymers of serving with z. B. styrene, acrylonitrile

example 1

a) Manufacture of

CH

244 g (2 mol) of 2,4-toluenediamine are dissolved in 1500 g of methanol at 60.degree. At 30 to 40 "C is passed into the solution 73 g (2 mol) of hydrogen chloride under cooling with tap water are subsequently. Added dropwise at 6O ^'J C in the course of 15 minutes, 106 g (l mol) of benzaldehyde The reaction mixture is then for 6. Stirred at 60 "C for hours and finally cooled to room temperature. The precipitated crystals of the tetramine dihydrochloride are filtered off with suction and suspended in 2000 g of water at 2OC. The suspension is then instilled in a solution of 200 g of NaOH in 1000 g of water ^{at 0 to 5 ° C. (ice cooling) over a period of 30 minutes.} The resulting suspension of tetramine is stirred for 4 hours without cooling. The precipitated crystals are filtered off with suction at room temperature and washed neutral with water. For the further implementation of the product it is extremely important that the adhering alkali is completely removed. The crystals are dried to constant weight then in a vacuum oven at 8O ⁰ C.

Yield 2K5 to 3001 · '(N6 Ims yil.VO ι
Theory) light-pale crystals. Ip 272 to 274 C

Analysis:

Itereehnei ... C 75.3. 117.25. N Ift.V. ( ¹ I l)%:
found .... C 75.0. 11 7.7. N Ι6.'λ i I 0.2 V

b) Manufacture of

CII

A '

^X VN ( ¹ O
NCO

In a solution of 500 g (about 5 mol) of phosgene in 2000 g of chlorobenzene, 332 g of (IMoI) finely-tilverted tetramine [preparation as described under a)] are added at -5 ° C. with vigorous stirring (exothermic reaction cooling with ice table salt), The resulting suspension is stirred overnight at 0 to 10 ° C. and then heated to 1IOC within 4 hours while passing in phosgene. Phosgene is passed in at this temperature until no more hydrogen chloride is split off (about 6 to 8 hours). The clear dark solution is blown out at 90 "C to 100 C with nitrogen. Then, C is added a little A-Kohlc at 50 to 60 ^C and stirred for I hour at this temperature. Then, it is filtered and concentrated in vacuo at 60 ° C to a residue of about 600 g is evaporated down. The concentrated solution of the tetraisocyanate is cooled to room temperature, the resulting synthetic pulp is filtered off with suction and dried at 50 to 60 ° C. in vacuo.

Yield: 366 g (= 84.5% of theory) of light gray crystals. Mp. 140 to 142 C.

Analysis:
Calculated:

NCO 38.5, CI total 0. Cl saponifiable 0%;
found:

NCO 38.1, Cl total 0.25. Cl saponifiable 0.15%.

Example 2
a) Manufacture of

CH ₃

(CH ₃ J ₂ CH-CH

NH ₂

NH,

Ausheule 2 (H ¹ I-; vlbliclic Kiisliil ·,. Ip. ÜIK bis

IJeavlinel ... C 72.6. HU N IK.8%:

I N 7

μοίuiuicii .... '■ 71.1).
b | Production of

(CII ₁ I ₂ CH - ( ¹ H

-I- N IK.7%.

CH,

<>
NCO

77.5 g of Tctramins prepared according to a) be me aiii- in Example I b) method specified in Clilorben / ol phosgenating. The solution obtained by blowing out with nitrogen and clarifying with Α-carbon is evaporated in vacuo at 60.degree. 100 g of the diisocyanate of the above constitution remain in the residue in the form of a dark brown oil.

Analysis:
Calculated
found .

C 65.8. H 4.5. N 13.9%;
C 64.8, H 4.8. N 13.6%.

Example 3
a) Manufacture of

CII ₃

CH ₃ -CH

250 g of toluene-2,4-diamine are introduced into a solution of 100 g of concentrated sulfuric acid in water at room temperature with stirring. To the resulting suspension is added dropwise 44 g of acetaldehyde at 0 to 1O ⁰ C. The resulting dark, clear solution is stirred for 1 hour at 20 ° C. and then poured into 3 l of dilute ammonia solution. The precipitated crystals of tetramines are suction filtered and dried in vacuo at 80 ⁰ C.

Yield: 175 g of light yellow crystals, melting point 174 to 175 ° C.

Analysis: C. 71.0, H 8.15, N 20.7%; Calculated ... C. 70.2, H 8.4, N 20.4%. found ....

195 g of tolylene-2,4-diamine hydrochloride and 122 g of tolylene-2,4-diamine are dissolved in 2,200 g of ethanol at 60 ⁰ C. In the solution are added at 60 ⁰ C 72g isobutyraldehyde, keeps the temperature for 3 hours and then cooled to room temperature. The precipitated tetramine hydrochloride is filtered off with suction and introduced into a solution of 50 g of sodium hydroxide in 21% of water. The crystals which precipitate are filtered off, washed neutral with water and dried at 90 ° C. in vacuo.

Molecular weight (osmotic in acetone):

Computed ... 270;
found 280.

b) Manufacture of

CH ₃ -CH

NCO

170 g of the tetramine obtained according to a) are analyzed:
1.51 chlorobenzene as described in Example Ib) - Calculated

benen method phosgenated and processed. When '

159 g of tetraisocyanate are obtained from the reaction product

Obieer formula found as light brown crystals from the enamel 5: point 96 to 98 ° C. C 62.9, H 4.0, N 14.7, NCO 46.0%.

- ¹ I I W '

Claims (1)

Pn ten actual : I. Tctnusocyiiniiie of the uncommon formula OCN CH ₃ NCO c— ^< \ ₌ V ~ ^NC0