DE2559833C2 - Aromatic onium salts and their uses - Google Patents

Description

CH ₃

J3

in which or

M phosphorus, arsenic or antimony: ok

R e ^; NEN monovalent aromatic Q (, _ u _; -hydrocarbon radical, which can contain 1 to 4 Qi- _S) -Aikoxy-, Qi_8) -alkyl, nitro, chlorine or hydroxy substituents or an optionally substituted by Br or NO> p- substituted r-phenacyl radical, the pyridyl or the furfuryl radical;

R 'is a Qi -8) -alkyl radical. which is optionally _{substituted by CH 3} O-, C ₂ H ₃ COO- or CHjCO-; 20 R ^{2 is} a polyvalent remainder of the form!

-CH ₂ -sQ PFT

3. Use of the aromatic onium salts according to claim 1 or 2 a! S photoinitiators for Hardening of epoxy resins.

25th

JO

35

40

X sulfur, selenium or tellurium;

ο an integer from 0 to 3:45

b is an integer from O up to and including 2 and c O or I

mean,

where the sum of a + b + c equals 3 or the

Valence of X is. to

excluding the compounds of the following formulas

S ⁺ PFT
CH ₃

60

(C ₆ H ₅ ) J (CH ₁ ) S PFT

65

2. Aromatic onium salt according to claim 1, characterized by the following formula:

The present invention relates to aromatic onium salts and their use, according to the preceding claims.

As described in US-PS 37 08 296, certain photosensitive aromatic diazonium salts used to harden epoxy resins. These aromatic diazonium salts set in by photolysis situ free a Lewis catalyst, which the rapid Can initiate polymerization of the epoxy resin. Although these one-part epoxy resin mixtures were rapid can result in curing compositions, but a stabilizer must be used during the Store these mixtures in the dark to avoid hardening as far as possible. Despite these measures gelation of the mixture can occur even in the absence of light. In addition, during the UV curing releases nitrogen, which can lead to defects in the film. Diazonium salts are generally thermally unstable and make use of them because of the possibility of uncontrolled decomposition Materials dangerous.

In j. Chem. Soc. (C), pp. 1764-1784 (1970) are S-alkylthiophenium salts, including those with PF (, - anions. These salts are strong alkylating agents.

In J. Amer. Chem. Soc. Pages 5360/61 (1964) is S-methylthiophenium hexafluorophosphate as a hydrogenation product of S-methylthiophpnium hexafluorophosphate called.

In Chemical Communications, page 409 (1968) is Diphenylmethyl-sulfonium-hexafluorophosphate called as electrolysis product.

In US-PS 34 12 046 are arylsulfonium salts described, which are exclusively salts with so-called simple anions, d. H. Chlorides, Nitrates, acetates, bromides or propionates and the like.

This arylsulfonium salts are used for heat curing, wherein a katalytisierter hardener from the arylsulfonium and an anhydride of a polycarboxylic acid is prepared by 30 minutes heating at 10O ⁰ C for this purpose, according to the Examples of US-PS 34 12 046 each as a precursor. The catalyzed hardeners obtained in this way require a relatively long time for the epoxy resin to gel. It follows from the table in column 4 of US-PS 34 12 046 that the catalyzed hardeners used there at 100 "C gelie-

Curing times of at least 3 and up to 23 minutes require.

In contrast, the present invention had the object of creating aromatic onium salts, which are more active in curing epoxy resins than the known arylsulfonium salts.

This object is achieved by the aromatic onium salts according to claim 1

The present invention is based on the discovery that radiation sensitive aromatic onium salts of sulfur, selenium or partur can be created when incorporated into epoxy resins result in compositions which are rapidly curable by radiation, consist of only one component, none Stabilizer need to be stable during storage at ambient temperatures, and all of them do not have the above-mentioned disadvantages of the aromatic diazonium salt compositions.

For example, a mixture of 80 parts of a commercially available epoxy resin with a radiation curing takes place Epoxy equivalents of 573 and 20 parts 4-vinylcyclohexene dioxide with 3% by weight triphenylsulfonium hexafluoroantimonate within a minute. 3 wt%

[(C ₆ Hs) ₃ Se] ^ (AsF ₆ ) - or (SbF ₆ ) "

in 4-vinylcyclohexene dioxide even only need 5 or 3 Seconds to radiation hardening.

Similarly short curing times result for the first-mentioned aromatic onium salt for others Epoxy resins and for c ":> s triphenylsulfonium hexafluoroarsenate.

Examples of radicals R are phenyl, ToIyI, naphthyl, anthryl and benzyl.

Examples of radicals R ¹ are mettiyl. Ethyl. -C ₂ H ₄ OCH ₃ , -CH ₂ COOC ₂ H ₅ and -CH ₂ COCHt.

The anions of the formula MF ₆ - in the above formula are PF ₆ -, AsF ₆ - and SbF ₆ -.

Examples of onium seeds of the above formula are:

PF7

O ₂ N

C-CH ₂ -SJ AsFT

SbFT

M and

C-CH ₂ Se

PF7

With the onium salts of the present invention Curable epoxy compositions can be created which comprise the following ingredients:

(A) An epoxy resin that has a higher state Molecular weight is polymerizable, selected from epoxy monomer, epoxy prepolymer, oxirane organic polymer and mixed

> gen of it, as well

(B) an effective amount of a radiation sensitive aromatic onium salt of the above formula, which can cause the hardening of (A) when exposed to radiant energy.

The onium salts of the invention of the above formula can be prepared as in the examples described, analogously to this or according to the methods described in the following publications

ι> are: Article by J. W. Knapczyk and W. E. McEwen in). Amer. Chem. Soc 91, 145 (1969); Article by A. L Maycock and G. A. Berchtold in J. Org. Chemistry 35, No. 8, 2532 (1970); U.S. Patent 2,8 07,648; Item from £. Goethals and P. De Radzetzky in Bull. Soc. Chim. BeIg.

2 »73, 546 (1964); Article by H. M. Leicester and F. W. Bergsif around. j. AfTicif. Chem. See 51,35S7 (i 929), etc.

The invention is explained in more detail below with reference to examples. All of these examples

specified parts by weight.
> ^

example 1

Triphenylselenoinium chloride was made according to the procedure by H. M. Leicester and F. W. Bergstrom in J. Amer. Chem. Soc. 51, 3587 (1929), where one started from diphenyl selenide. By adding sodium hexafluoroarsenate or potassium hexefluoroantimonate the corresponding hexafluoroarsenate were added to an aqueous solution of triphenylselenonium chloride and hexafluoroantimonate salts.

The products were white crystalline solids that were dried in vacuo.

Example 2

With stirring, 89 parts of Ahimintamchlorid were in

♦ ο added small amounts to a solution of 122 parts of 2,6-xylenol in 505.12 parts of carbon disulfide at IC ⁰ C. 79.5 parts of thionyl chloride were added dropwise to the greenish solution obtained, the temperature being kept between 10 and 15 ° C. A black precipitate was obtained, which was stirred in the solution for a further two hours and then poured onto 1000 parts of ice which contained 50 parts of concentrated HCl. The mixture was heated on a steam bath _{to remove the CS 2} and decompose the complex. An amber-colored solid was obtained which was filtered, washed with water and dried.

_{11.4 parts of KAsF 6} and 10 parts of water were added to a solution of 21.5 parts of the above crude product in about 117 parts of hot absolute alcohol. The reaction mixture was stirred and more water was added to cause the product to precipitate. The product was filtered, washed with water and washed with water ^. dried. A material with cmsrn, melting point of 245 to 25 ° C. was obtained. According to the manufacturing process and elemental analysis _{for C 21} H _{27 OtSAsF 6} , calculated 49.3% C. 4.62% H, 5.43% S and found 49.4% C, 4.59% H and 5.55% S. the product was tris (3,5-dimethyl-4-hydroxyphenyl) sul-

& 5 fonium hexafluoroarsenate.

Claims (1)

Patent claims: I. Aromatic onium salts of the general formula 5 r X] ⁺ CH HO