DE2403407C3 - Process for the reaction of epoxy compounds with phenols - Google Patents

Description

H, C-

O = C

R '

C = P-R

R C = O

wherein each substituent R is a phenyl or alkyl group having 1 to 18 carbon atoms and R 'represents hydrogen, a phenyl or alkyl group having 1 to 4 carbon atoms, in an amount from 0.001 to 10 percent by weight based on the weight of the epoxy compound and the phenol, used and that the reaction is carried out at a temperature in the range from 50 to 225 ° C.

2. The method according to claim 1, characterized in that the catalyst is used in an amount from 0.05 to 5 percent by weight based on the weight of the epoxy compound and the phenol, begins.

3. The method according to claim 1, characterized in that a polyepoxide of the formula

/
CH ₂

CH - CH ₂ -O

i - <^ (b \ - 0-CH ₂ CH-CH ₂

wherein the substituents R, Ri, R ₂ and R _{3 are} each hydrogen, chlorine and / or bromine and A is an alkylene or alkylidene group with 1 to 4 carbon atoms, -S-, -SS-, -SO-,

O
CH ₂ CHCH ₂

SO2 -, —CO— or —O— is used.

4. The method according to claim 1, characterized in that that use a polyepoxide! will which of the general formula

CH ₂ CHCH ₂

O
O - CH ₂ CHCH ₂

corresponds to where R is hydrogen or an alkyl group having 1 to 4 carbon atoms and π is 0.1-10.
5. The method according to any one of the preceding claims, characterized in that the phenol used is a polyhydric phenol which has the general formula

HO R

R OH

where each substituent R is hydrogen, chlorine or bromine and A is an alkylene or alkylidene group having 1 to 4 carbon atoms, -S-, -SS-, -SO ₂ -, -CO- or -O-.

The invention relates to a method for converting phenols, amines, mercaptans or water, for

of epoxy compounds with phenols in the presence of _b 5 formation of the corresponding phenol ethers, or amines

a catalyst. Thioether.

Epoxy compounds settle with a variety The implementation of epoxy resins with suitable

of compounds with active hydrogen, e.g. phenols, is a convenient method to determine the molecular

increase the weight of the epoxy resin, but otherwise maintain the basic chemical properties.

The reaction of epoxy resins with phenolic hydroxyl groups is quite slow, but it will accelerated (catalyzed) by bases and quaternary ammonium compounds. When using such catalysts typically encounter several problems. For example: this is how they usually react ailein with the epoxy resin and thus close the distribution possibility of a product that is called »precatalyzed Epoxy Resin «is known from. Second, they are typically not selective as they implement the Epoxy resin with both the phenolic hydroxyl groups of the reactant and the aliphatic groups Promote hydroxyl groups in the product. This leads to undesired branching and / oJ.er Networking. Thirdly, they need to be close to the epoxy resin and the phenolic raw materials mixed after use, which is due to the high speed of the subsequent reaction is. In these circumstances, formulation and complete mixing is difficult.

These and other problems are now solved by the invention.

The subject of the invention is therefore the method defined in the claims.

The catalysts used according to the invention are at the conventional storage temperatures essentially non-reactive with epoxy resins, jo Therefore, the epoxy resin and the catalyst can now be precatalyzed to form new types Epoxy resins are mixed.

Furthermore, the catalysts used in the present invention are specific in that they have the J5 Accelerate the reaction of epoxy resins with phenolic hydroxyl groups far more than the reaction the epoxy resin having aliphatic hydroxyl groups in the reaction product. Thus, if at all, only slightly branched and / or crosslinked product through conversion of a difunctional epoxy resin formed with a difunctional phenol in the presence of the catalysts used according to the invention.

Finally, the catalysts used in this invention fade unique in that their activity is katalylische latent at temperatures below 50 ⁰ C. Mixtures of epoxy resins, phenols and the catalysts used according to the invention therefore have a greatly increased pot life compared to mixtures according to the prior art. In cases where the epoxy resin is essentially non-reactive with the phenol (in the absence of a catalyst or at elevated temperature), the catalysts used according to the invention can be added and the mixtures can be marketed as fully formulated compositions.

The catalysts used have the basic core:

—C-

-C = P-

O = C

C = - 0

Such compounds are conventionally made by using a trihydrocarbylphosphine Maleimide or an inert substituted derivative thereof is brought into contact.

The catalysts used according to the invention are compounds of the general formula

H ₁ C-

O = C

R.
C = PR

R.
C = O

R '

wherein R is a phenyl or alkyl group having 1 to 18 carbon atoms and R 'is a hydrogen atom, a Denote phenyl or alkyl groups with 1 to 4 carbon atoms.

Illustrative examples are e.g. B. the following compounds: 3-Trimethyl-, 3-TriäthyI-, 3-Tri (n-butyl) -, 3-Trihexyl-, 3-tridecyl-, 3-tridodecyl-, 3-trioctadecyl-, 3-di (n-butyl) -3-hexyl-, 3-triphenyl-phosphoranylidene-2,5-pyrrolidinedione and the corresponding compounds which have an N-substituent, such as 1-methyl, 1-ethyl or carry 1-phenyl. Mixtures of such compounds can also be used.

The amount of catalyst used can be varied over a wide range. The catalyst is in concentrations of 0.001 to 10 wt .-%, based on the combined weight of the Epoxy resin and the phenol. The catalyst is preferably used in amounts of 0.05 to 5% by weight used.

The epoxy resins and the polyhydric phenols are each known classes of compounds, as they are, for. Am "Handbook of Epoxy Resins" by Lee and Neville, McGraw-Hill, New York (1967). Every member of these known classes is for the purpose suitable for the invention.

However, there are two preferred subclasses of epoxy resins. The first subclass corresponds to general formula

O
O - CH ₂ CHCH ₂

OO - CH ₂ CHCH ₂

CH ₂

-CH

O
O - CH ₂ CHCH ₂

where R is hydrogen or an alkyl group having 1 to 4 carbon atoms and π is 0.1 to 10, preferably I is to 2. The preparation of these polyepoxides is described in US Pat. Nos. 2,216,099 and 2,658,885

described. The second subclass corresponds to the general formula

CH ₂

CH - CH ₂ -O

Ο-CH ₂ CH-CH ₂

wherein the substituents R, Ri, R ₂ and R3 are independently 10 alkylidene (e.g. isopropylidene) groups with 1 to 4 of each other hydrogen, bromine and / or chlorine carbon atoms, and wherein A is an alkylene (e.g. methylene ) or

-S— —S —S S S C— or —O—

Il ο

means. Preferred phenols are those which have 2 to 6 hydroxyl groups and 6 to 30 carbon atoms to have. Phenols of the general formula are particularly preferred

HO

correspond, in which R is hydrogen, chlorine and / or bromine and A has the meaning defined above. 4,4'-Isopropylidenediphenol is the most preferred phenol.

The ratio of epoxy resin to phenol in the process of the invention can be varied over a wide range Vary the range according to the desired product. We.in z. B. a product is desired that is terminated with a phenol ether group, then naturally an excess of phenol is used.

In most cases the reactants will be liquid and not a solvent or diluent needed. In other cases where one or both of the reactants are solids or viscous Liquids, an inert solvent or diluent can be used with advantage will. Suitable inert solvents or diluents are, for. B. ketones (such as acetone or Methyl ethyl ketone) and hydrocarbons (e.g. benzene, toluene, xylene, cyclohexane and ligroin).

When carrying out the process, the reaction mixture is heated to temperatures in the range from 50% heated to 225 ° C (preferably 100 to 175 ° C) until one exothermic reaction begins. After the exothermic reaction peaks, it becomes a heated for a further period of time in the same area to achieve essentially complete conversion guarantee. Atmospheric or superatmospheric pressures, e.g. B. up to 14.6 at, are common.

The reaction products obtained by reacting an epoxy compound with a phenol in the presence of the According to the invention provided catalysts are obtained are phenolic hydroxy ethers, the aliphatic carry secondary hydroxyl groups. Such aliphatic hydroxyl groups are formed in the ring opening reaction formed between the oxirane and phenolic hydroxyl groups. Continue to bear in the case of Using epoxy resins, the reaction products have one or more terminal epoxy groups or one or more phenolic hydroxyl groups, depending in the individual case on the ratio of the reactants depends. There are therefore reactive intermediates that work with many known polyfunctional curing agents can be cured (crosslinked) to form hard, insoluble solids that are suitable coatings represent. The cured products (especially those with high molecular weight) are as Surface coatings, as adhesive layers in laminates, as coatings or thread wraps or for suitable for structural purposes. The reaction products that result from halogenating (especially brominated) Phenols produced are particularly suitable for flame retardant purposes as they are used to do so tend to be self-extinguishing. They are therefore suitable for hardened coatings for wood panels as well as for adhesive layers in wood laminates.

example 1

In a reaction vessel with a stirring device and a temperature receiving device were provided under a nitrogen flow of 75.79 parts by weight of the diglycidyl ether of 4,4'-isopropylidenediphenol, 24.21 parts of 4,4'-isopropylidenediphenol (bisphenol A) and 0.15 parts of 3- (triphenylphosphoranylidene) -2,5-pyrrolidinedione, dissolved in about 5 ml of methanol. The stirred reaction mixture was from Ambient temperature heated to 150 ° C at a rate of 3 ° C7nin. At 150 ° C the Heat taken away. An exothermic reaction took place, which peaked at 213 ° C achieve .. e. The reaction mixture was another 2.5 hours, after the exothermic reaction had subsided, heated to 150 ° C. Theoretical epoxy content: 8.20%. Observed content: 8.13%.

Examples 2 and 3

Similarly, there was 377.5 g of the diglycidyl ether of bisphenol A with 122.5 g of bisphenol A in the presence of (2) 1-methyl-3- (triphenylphosphoranylidene) -2,5-pyrrolidinedione (0.573 g) and (3) 1-phenyl-3- (iriphenylphosphoranylidene) -2,5-pyrrolidinedione (0.68 g) implemented. In each case the reaction mixture was

b5 heated to 150 ⁰ C at a rate of about 5 ° C / min and the temperature was allowed to rise.

Each mixture was then heated to 160 ° C for 5 hours. The theoretical epoxy content for the

«Sift =».

Examples 2 and 3 is 8%. Values of 7.31% and 7.82% were found for Examples 2 and 3.

Examples 4 to 6

The procedure of Example 2 was repeated except that different catalysts were used and that the Enderhitzungsstufe was. Carried out for 2 hrs. At 160 ⁰ C instead of 5 hours long. (4) l-Phenyl-3- (tri-n-butylphosphoranylidene) -2,5-pyrrolidinedione (0.458 g), (5) 3- (di-

ethylphenylphosphoranylidene) -2,5-pyrrolidinedione
(0.408 g) and (6) i- (Diphenyläthylphosphoranyliden) -2,5-pyrroIidindione (0.478 g) used. The theoretical epoxide content for Examples 4 to 6 is 8%. 7.82%, 7.84% and 7.92% were observed for Examples 4 to 6.

Pre-catalyzed epoxy resins were prepared by mixing the diglycidyl ether of bisphenol A with the catalysts given in Examples 1 to 6. ^{These mixtures were stored at 50 °} C. for up to four weeks and used in experiments according to Examples 1 to 6. The stored mixtures showed little, if any, loss in reactivity. Their reaction products with phenols had essentially the same properties as the products of Examples 1 to 6.

The products of Examples 1 through 6 were essentially linear compounds. You are with conventional hardening agents, e.g. B. dicyanamide, polyamines and anhydrides, curable (crosslinkable). the Cured resins are tough solvent-resistant materials that are suitable for coatings.

Branched and / or crosslinked products are produced in the process of the invention in a similar manner prepared by (1) an epoxy resin having at least three epoxy groups per molecule with a phenol with at least two hydroxyl groups or (2) an epoxy resin with at least two epoxy groups per Molecule with a phenol with at least three

Tabel

Reacts hydroxyl groups in the presence of the catalysts used according to the invention. Such branched ones and / or crosslinked products are equally suitable as coatings.

Example 7

Equimolar amounts of 1,2-epoxydodecane and phenol in the presence of air and 0.10 percent by weight, based on the total weight of the reactants, 3- (triphenylphosphoranylidene) -2,5-pyrrolo idindion 3 hours at 14O ⁰ C heated . A parallel test in the absence of the catalyst was carried out at the same time. After 3 hours the reaction mixtures were cooled to ambient temperature to give viscous oils. The crude products were dissolved in methylene chloride and washed with 15% NaOH and water and then dried and distilled. The distilled product was deprived of epoxy groups and had a molecular weight of 278 as determined by mass spectrophotometry. This is the correct molecular weight for i-phenoxy-2-dodecanol. The yield of isolated product in the experiment according to the invention with a catalyst was 87.9%. Without a catalyst, the yield was 40.1%.

The catalysts used according to the invention are the catalysts known from DE-AS 18 12 972 superior as they result in blends with better storage stability. This is shown by the following described comparative experiments.

In these experiments mixtures of liquid diglycidyl ether of bis-phenol A with a Epoxy equivalent weight of 187 and 0.15 percent by weight of the respective catalyst prepared and 10 Stored for weeks at ambient temperature. The table below shows the catalysts used as well as the epoxy group content and the viscosity at the beginning and at the end of the storage period.

catalyst

% Epoxy viscosity at 25 C cps

before after before after

According to DT-AS 1812972
Methyl triphenylphosphonium iodide

According to the invention

1-phenyl-3- (tri-n-butylphosphoranylidene) -2,5-pyrrolidinedione

3- (triphenylphosphoranylidene) -2,5-pyrrolidinedione

22.51 21.68

22.62 22.31

22.58 22.23

12910

13000
12825

27321

16217
16541

030208/192

Claims (1)

Patent claims: 1. Process for the reaction of epoxy compounds with phenols in the presence of a catalyst, characterized in that the catalyst used is a compound of the general formula