DE2533123A1 - HYDROLYSIS-STABLE POLYTRIAZINE AND A PROCESS FOR THEIR PRODUCTION - Google Patents

Description

Bayer Aktiengesellschaft

Central Patents Department. Trademarks and licenses

509 Leverkusen. Bayerwerk

July 23, 1975

Hydrolysis-stable polytriazines and a process for their preparation

The invention "relates to hydrolysis-stable polytriazines polyfunctional aromatic cyanic acid esters with alkyl or Phenyl radicals or halogen atoms at least in the ortho, ortho 'position to at least one -OC'N group and a process for their preparation.

From DT-PS 1 190 184 it is known to produce high molecular weight polytriazines by polymerizing di- or polyfunctional aromatic cyanic acid esters, optionally in the presence of substances which promote the polymerization, at an elevated temperature. The polymers are distinguished, for example, by a remarkable stability at higher temperatures and, after a sufficiently long heat treatment, have a thermoset character. The resistance of the polytriazines to acids and various solvents should also be emphasized. If samples are stored for three months in benzene, dimethylformamide, premium gasoline, conc. Acetic acid, trichloroacetic acid, chromic acid, aqueous formaldehyde solution, heating oil, saturated sodium phosphate solution and conc. Hydrogen peroxide showed no changes in the test specimens (see Kunststoffe 58 , Issue 19, pages 827 to 832 (1968)).

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Furthermore, it was found by VY Korshak et al (see Vysokomolekulyarnye soedineniya 1974 , No. 1, pages 15 to 21) that the thermal and thermooxidative destruction of polytriazines based on aromatic cyanic acid esters is strongly influenced by moisture.

The object of the present invention was to improve the polytriazines with regard to their hydrolytic stability.

The object was achieved in that for the polytrimerization polyfunctional aromatic cyanic acid esters with alkyl or phenyl radicals or halogen atoms are used at least in the ortho, ortho 'position to at least one -OCN group will.

The invention thus relates to a process for the preparation of hydrolysis-stable polytriazines by polytrimerization polyvalent aromatic cyanic acid esters, possibly in the presence of catalysts that promote polytrimerization, characterized in that the cyanic acid esters used are those containing alkyl or phenyl radicals or halogen atoms at least in ortho, ortho · position to at least one -OCN group included.

The invention also relates to the polytriazines obtained by this process.

The aromatic cyanic acid esters correspond to the general IOrmel (I)

A (OCN) _n (I)

in the

A is an aromatic radical or an aromatic radical which is interrupted by bridges and has alkyl or phenyl radicals or halogen atoms at least in the ortho, ortho 'position to at least one -OCN group and

η one of the numbers 2 to 4

mean.

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The aromatic cyanic acid esters of the formula (I) to be used according to the invention can be prepared by the process of GB-PS 1 007 790 can be made.

1-1.1 mol of cyanogen halide and 1 mol of a base or base mixture can be used per phenolic hydroxyl group. The reaction temperatures can be between -40 G and +65 ⁰ C. Inorganic bases such as sodium hydroxide, potassium hydroxide, soda, potash, calcium hydroxide or tert-amines such as trimethylamine or triethylamine can be used as bases, and water, alcohols, ketones, hydrocarbons, chlorinated hydrocarbons or mixtures thereof can be used as solvents or suspending agents.

The aromatic cyanic acid esters preferably correspond to the general formula (II)

(NCO)

(OCN),

(II)

_m f λ

(R) ₁

where "mean

Halogen, linear or branched C ₁ to Cg-alkyl or phenyl, where several radicals R need not be the same, with the proviso that at least the ortho, ortho 'position to at least one cyanate ester group is substituted by R; has the same meaning as R or group (III)

(III)

again at least the ortho, ortho 'position to at least one cyanate ester group is substituted by R ';

A. a simple bond, an _{alkylene group with 1 to 9 carbon atoms optionally substituted by C 1} to C alkyl or phenyl, a cycloaliphatic or aromatic,

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5- or 6-membered sections possibly interrupted by oxygen Ring, oxygen, the sulfonyl group (-) the carbonyldioxy group (-OCO-), the carbonyl group;

Il

a is the number 1 or 2,
b one of the numbers 2 to 4,
c one of the numbers 2 to 4,
d the number 1 or 2,
e O or 1,

with one condition that the sum of a and d (a + d) always results in one of the numbers 2 to 4.

In particular, in the formula (II)

R chlorine or bromine, C ₁ -C.-alkyl,

A is a simple bond, oxygen, the sulfonyl group, the carbonyl group, the carbonyldioxy group, the methylene, ethylene, the 2,2-propylene group

GH *

I J

(-C-), the cyclohexylene radical; CH-

a is the number 1 if e = 1 and the number 2 if e = 0; b the number 2,

c is the number 2,

d the numbers 0 or 1 and

e the numbers 0 or 1,

with the condition that a + d = 2 or 3.

The following compounds which come under formula (I) may be mentioned by way of example:

2,4-diethyl-1,3-dicyanatobenzene, 2,6-di-tert. -butyl-1,4-dicyanatobenzene, tetramethyl-1,4-dicyanatobenzene, 2,4,6-trimethyl-1,3-dicyanatobenzene, 2,4,6-trimethyl-1,3,5-tricyanatobenzene; 3,3 ', 5,5' tetramethyl-4,4 ~ ^f -dicyanatodiphenyl, 3,3 ', 5,5'-tetrachloro-4,4'-dicyanatodiphenyl,

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3,3 ', 5,5'-tetramethyl 1-4,4'-dicyanatodiphenyl ether, 3,3 ', 5,5'-tetrachloro-4,4'-dicyanatodiphenyl ether, 3,3 ', 5,5' -Tetra "bromo-4,4'-dicyanato-diphenyl ether, 3,3 ', 5,5'-tetramethyl-4,4'-dicyanato-diphenylsulfone, 3,3 ', 5,5'-tetrachloro-4,4'-dicyanato-diphenylsulfone, 3,3 ', 5,5'-tetrabromo-4,4'-dicyanato-diphenylsulfone, 2,2'Bis (3,5-dimethyl-4-cyanatophenyl) propane, 2,2-bis (3,5-dichloro-4-cyanaophenyl) propane, 2,2-bis (3,5-dibromo-4-cyanatophenyl) propane.

If particularly pure aromatic cyanic acid esters with a long shelf life are to be used, it is recommended to work analogously to the method of German patent applications P 25 29 486.4 or P 25 29 487.5, which the Relate to the production of high-purity polyvalent cyanic acid esters. According to German patent application P 25 29 486.4 are di- or polytrialkylammonium phenolates (e.g. polytriethylammonium phenolates), optionally in the presence of catalytic amounts of trialkylamines, such as triethylamine, with an excess of cyanogen halide in an organic solvent to give the corresponding aromatic cyanic acid esters implemented.

According to German patent application ρ 25 29 487.5 alkali or Alkaline earth salt, preferably sodium, potassium, calcium and barium salts of aromatic di- or polyhydroxy compounds with cyanogen halide in a solvent, optionally in the presence of catalytic amounts of a tertiary amine implemented.

1 to 2 moles, preferably 1 to 1.4 moles, of cyanogen halide can be used per phenolic hydroxyl group; 1 to 1.8 moles, preferred 1 to 1.3 moles of a base or base mixture are used be, the base or the base mixture is always used in deficit to the cyanogen halide.

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The following solvents can be used, for example: water, lower aliphatic alcohols such as methanol, Ethanol, propanol, isopropanol, butanediol; aliphatic Ketones, such as acetone, methyl ethyl ketone, diethyl ketone, methyl isopropyl ketone, Methyl isobutyl ketone; aliphatic or aromatic hydrocarbons, with aliphatic hydrocarbons being preferred for the distillation fractions that occur naturally in mixtures, such as petroleum ether, light petrol, gasoline are used, while, for example, benzene, toluene and xylenes may be mentioned as aromatic hydrocarbons; aliphatic and aromatic chlorohydrocarbons such as dichloroethane, perchlorethylene, chlorobenzene, dichlorobenzene; Ether how Diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, di-sec-butyl ether; Nitro hydrocarbons, such as nitromethane, Nitrobenzene, nitrotoluene; Amide, such as dimethylformamide, Dimethyl acetamide; and their mixtures thereof.

The inorganic or organic bases used are those mentioned in GB-PS 1 007 790.

These processes are generally carried in the temperature range between -40 ⁰ C and +65 ⁰ O, preferably carried out between 0 and 30 ⁰ O. When using cyanogen chloride, the reaction is preferably carried out below the boiling point (13 ^° C.), but when using cyanogen bromide temperatures of over 50 ^° C. can also be used.

Tertiary amines based on the German patent application P 25 29 487.5 in catalytic amounts (0.001 to 10 wt .- ^, in particular 0.001 to 1.0 wt .- $, based on Alkali or alkaline earth phenolate) find use, according to the general formula

NR ₅

I <-

^R 3

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-V

in the

R ₁ , R ₂ , R _{3 are} alkyl, aryl and cycloalkyl radicals, which do not need to be identical to one another, with 1 ″ denote up to 36 carbon atoms, in particular up to 18 carbon atoms.

For example:

Trimethylamine, triethylamine, methyl diethylamine, Tripopylamine, tributylamine, methyldibutylamine, dinonylmethylamine, dimethylstearylamine, Dimethylcyclohexylamine, diethylaniline.

The aromatic cyanic acid esters can be converted into ^{partially crosslinked prepolymers soluble in organic solvents by heating to about 30 °} C. to 250 ^° C., preferably 50 ^° C. to 200 ^° C., in bulk or in solution, optionally in the presence of a catalyst or catalyst mixture . The prepolymers are polymeric triazines containing cyanate groups and have a liquid, waxy or solid consistency and are soluble in organic solvents. They are extremely stable in storage. As the IR spectrum shows, in addition to the triazine structure, they also have the band of the -OCN group at 4.5 / U.

The prepolymers may be prepared by heating to about 120 ⁰ O ⁰ O 35O, preferably from 150 ⁰ C to 25O ⁰ C, optionally in the presence of a catalyst or catalyst mixture in solution or substance can be converted into high molecular weight polymers with triazine structure. The end products are practically insoluble in solvents and can no longer be melted. As the infrared spectrum shows, apart from triazine structures, there are no other linking principles in the polymer.

Of course, the polytriazines can also be produced in

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take place in one process step.

_{Acids, bases, salts, nitrogen and phosphorus compounds, for example Lewis acids such as AlCl 5} , BF ,, FeCl ,, TiCl., ZnClp, SnCl, can be used as catalysts in the production of the prepolymer or the high molecular weight end polymer with triazine structures. , Protonic acids such as HCl, Η, ΡΟ .; aromatic hydroxy compounds such as phenol, p-nitrophenol, catechol, dihydroxynaphthalene; Sodium hydroxide, sodium methylate, sodium phenolate, trimethylamine, triethylamine, tributylamine, diazabicyclo (2,2,2) octane, quinoline, isoquinoline, tetrahydroisoquinoline, tetraethylammonium chloride, pyridine-N-oxide, tributylphosphine, phospholine-A ^ -I-oxa-1- phenyl, zinc octoate, tin octoate, tin naphthenate, and mixtures thereof.

The catalysts can be used in amounts of 0.001 to 10% by weight, based on prepolymer or on cyanic acid esters containing cyanamide groups, or, if desired, in even larger amounts.
The aromatic cyanic acid esters or the prepolymers can, dissolved in inert solvents such as acetone, benzene, xylene, chlorobenzene, ethyl acetate, tetrahydrofuran, dibutyl ether, dimethylformamide, or in powder form for the production of coatings on substrates such as metals, ceramics, glass, pottery, etc. can be used or dissolved in organic solvents, as impregnating varnish or laminating resins. If desired, the prepolymers can be combined with fillers, pigments, glass fibers, metal fibers and glass fabrics and used for the production of molded articles or laminates. After curing, yellow to brown-colored, transparent end products with high hardness and temperature resistance are obtained. The particular advantage of the polytriazines obtained according to the invention, in addition to their high heat resistance, is their insensitivity to hydrolyzing chemicals such as alkaline solutions.

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The percentages and parts given in the examples relate to weight, unless otherwise stated.

Example 1 :

15 g of bis-2,2- (4-cyanato-3,5-dimethyl-phenyl) propane zinc octoate are added and heated to 140 ⁰ C with 0.03 wt .-%. A clear melt is obtained, which is kept at 140 ° C. for 8 hours. After cooling, n _D ⁹⁰ is obtained a waxy at room temperature prepolymer of high viscosity and from about 80 ⁰ C is flowable from about 50 C: 1.5520-90 The IR spectrum of this prepolymer shows the characteristic band for the -OCN- Group at 4.5 / U and for the s-triazine ring at 6.4 / U and 7.25 / U. The hardening to a honey-colored, very hard polytriazine takes place at 200 ^° C. within 6 hours.

Hydrolysis test :

The polytriazine produced in this way is through 120 hours Cooking in 40% NaOH, in 25% ammonia solution or not dissolved in 20% hydrochloric acid. A polytriazine, made from bis-2,2- (4-cyanatophenyl) -propane is against it hydrolytically split into cyanuric acid and bisphenol-A after only 5 hours.

Example 2 ;

20 g of 2,2- (4-cyanato-3,5-dimethyl-phenyl) -propane are mixed with 0.1 wt .- # zinc octoate and heated for 3 hours at 150 ⁰ C. A clear, yellow-colored melt is obtained. The temperature is then increased to 180 ^° C. and kept at this temperature for 3 hours. After cooling, a very hard, honey-colored polytriazine is obtained.

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Example 3 :

1 kg of bis-2,2- (4-cyanat0-3,5-d.imethyl-phenyl) -propane are mixed with 0.5% by weight of pyrocatechol and 0.5% by weight of diazabicyclo- (2.2, 2) Octane is added and the mixture is heated at 150 ° C. for 8 hours while stirring. The highly viscous melt is then poured out. A pale yellow colored prepolymer which is flowable above 80 ⁰ C, _D ⁹⁰ = 1.5520-90 n. The IR spectrum shows the characteristic bands at 4.5 / U (-0-C = N) and 6.4 / U and 7.25 / U (s-triazine). 15 g of this prepolymer are mixed with 0.1 part by weight of stannous octoate and 96 cured within 3 hours at 190 ⁰ C to a very hard, light brown polytriazine.

Example 4 ;

10 g of 2,6-di-tert-butyl-hydrochinondicyanat are mixed with 0.1 wt .-% Zincchlorid and heated for 3 hours at 120 ⁰ C. The product obtained is then ^{kept at 200 °} C. for 3 hours. After cooling, a hard, yellow-brown colored polymer is obtained with the bands characteristic of the s-triazine ring at 6.4 / U and 7.25 / U.

Example 5 :

20 g of 2,4,6-trimethylresorcinol dicyanate are mixed with 0.02% by weight of tin octoate and heated to 150 ° C. for 5 hours. A prepolymer which solidifies slowly at room temperature is obtained (IR spectrum: -0-C = N at 4.5 / U, s-triazine ring at 6.4 / U and 7.25 / U). The curing of this prepolymer to a very hard, brown polytriazine takes place at 220 ⁰ C within

2 hours.

Example 6 ;

10 g of 2,3,5,6-tetramethylhydroquinone dicyanate are 0.01 % By weight of tin octoate heated to 160 ° C. for 4 hours. One receives a

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Hard, brittle prepolymer at room temperature, which is highly viscous above 75 ° C. The curing of this prepolymer takes place at 230 ^° C. within 5 hours. A brown, very hard polytriazine is obtained.

Example 7 ;

10 g of bis-2,2- (4-cyanat0-3,5-dichlorophenyl) propane are slowly heated to 150.degree. After 3 hours the temperature is increased to 180 ^° C. and after a further hour to 220 ^° C. After a total of 5 hours, a brown prepolymer is obtained with the characteristic s-triazine ring bands in the IR spectrum.

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Claims (3)

Claims: jo λ /.Ο ο ό \ Zo 1. Process for the preparation of hydrolysis-stable polytriazines by polytrimerization of polyvalent aromatic Cyanic acid esters or their prepolymers, optionally in the presence of catalysts which promote the polytrimerization, thereby characterized in that the cyanic acid esters used are those containing alkyl or phenyl radicals or halogen atoms at least in ortho, ortho 'position to at least one -OCN group included. 2. The method according to claim 1, characterized in that aromatic cyanic acid esters of the general formula (I) A (OCN) _n (I) in the A is an aromatic radical or an aromatic radical which is interrupted by bridges and has alkyl or phenyl radicals or halogen atoms at least in the ortho, ortho 'position to at least one -OCN group and η is one of the numbers 2 to 4, can be used. 3. Polytriazines obtained according to claim 1 or 2. Le A 16 471 - 12 - 609886/0962