DE3934428A1 - Room temp.-curable epoxide resin compsns. - contain, as hardener, aliphatic or cyclo-aliphatic amine, di-sec. di:amine, and N-butyl-benzene-sulphonamide - Google Patents

Abstract

Hardenable compsns. (I) comprise (A) epoxide resin with more than 1 epoxy gp. per mol., hardenable at room temp., (B) mixt. of (B1) 1 mol. of aliphatic or cycloaliphatic polyamine contg. at least 3 active H atoms and (B2) 0.25-4 mol. disec. diamine of formula (II) (where R = branched or unbranched 2-18C alkylene or cycloalkylene opt. substd. by 1 or 2 OH, 1 or more CH2 gps. opt. being substd. by O; R' = branched or unbranched 3-20C alkyl opt. substd. by 1 or 2 OH, 1 or more CH2 gps. opt. being substd. by O, or R' = cyanoethyl or =CH2CH2-C(:O)O-tert.Bu), (C) 50-350 wt.%, on (B), N-butylbenzenesulphonamide (II). (I) pref. contain fillers, pigments and accelerators. USE/ADVANTAGE - Coatings, partic. for roofs and floors, and adhesives, sealants, moulded articles. Cured prod. has good adhesion, flexibility, impact toughness, tensile strength, and is resistant to petrol.

Description

The present invention relates to room temperature curable Epoxy resin mixtures consisting of epoxy resins with two or more Epoxy groups, (cyclo) aliphatic polyamines having at least 3 ak tive H atoms in the molecule, di-secondary diamines and N-butylbenzene sulfonamide (BBSA).

The polyamine-cured epoxy resins are characterized in the Practice by a number of desirable properties, such as. B. good adhesion on all kinds of substrates, good solvent resistance and high resistance to chemicals. As a result their high crosslink density are amine-hardened epoxy resins - before all based on bisphenol A - brittle, with glass transition temperatures Above 20 ° C and therefore, especially in applications for which Impact and shock resistance and high flexibility are required be made more flexible. The z. Z. in the construction sector very often set flexibilized epoxy resins are described in DE-OS 31 51 592 described. These are polyepoxides with poly etherurethaneurea amine with 2 or more reactive amine waters hardened substances per molecule. A decisive disadvantage these flexibilized epoxy resins is their unsatisfactory Gasoline resistance (about 20% weight gain after 3 months in gasoline).

The object of the present invention was to overcome this disadvantage winches and curable synthetic resin mixtures that are too benzinbe permanent, well-adherent, flexible coatings, adhesives, you materials and moldings with high impact strength and tensile strength cure.

This object has surprisingly been achieved in that as Hardener a mixture of (cyclo) aliphatic polyamines with minde at least three active H atoms in the molecule and di-secondary diamines  together with N-butylbenzenesulfonamide (BBSA) of the formula

starts.

The invention therefore curable epoxy resins with more as one epoxide group per molecule that cure at room temperature, which are characterized in that as hardener a polyamine / disecondary diamine mixture consisting of

• a1 1 mole of (cyclo) aliphatic polyamine having at least 3 active H atoms per molecule and
• a2 0.25 to 4 moles of disecondary diamine of the formula: wherein R is a branched or unbranched, optionally substituted with 1 to 2 OH groups (cyclo) alkylene having 2 to 18 carbon atoms, and one or more methylene groups may be replaced by O atoms; R 'is a branched or unbranched ter, optionally substituted with 1 to 2 OH groups alkyl radical having 3 to 20 carbon atoms, and one or more methylene groups may be replaced by O atoms; or R ' means together with
• b 50 to 350 wt .-%, based on the hardener mixture, of butylben Zolsulfonamid is used.

The epoxy resins can conventional fillers, pigments and Reaktionsbe accelerator included.

The epoxy resins used in the invention contained in the cut more than one epoxy group in the molecule and can glycidyl ethers of polyhydric alcohols, such as. B. glycerol, hydrogenated Diphenylolpropane or of polyhydric phenols, such as. Resorcinol, Diphenylolpropane or phenol-aldehyde condensates. It can also glycidyl esters of polybasic carboxylic acids, such as hexahydrophthal acid or dimerized fatty acids. The epoxide wer te of said compounds are approximately between 0.01 to 0.6. Particularly preferred is the use of liquid epoxy resins Basis of epichlorohydrin and diphenylolpropane or methane with a Molecular weight of 340 to 500. Optionally, reactive Thinner, such as. Butyl glycidyl ether, neopentyl glycol diglycidyl ethers, Hexandioldiglycidylether, phenyl glycidyl ether, co-used become. The amine hardener component is composed of a poly amine / di-secondary diamine mixture together, with per mole of polyamine 0.25 to 4 moles of di-secondary diamine in the presence of 50 to 350 % By weight of N-butylbenzenesulfonamide (based on the amine mixture) be set. Examples of polyamines which may be mentioned are: ethylene diamine, diethylenetriamine, 1.2 (1.3) diaminopropane, 1.3 (1.4) diamino butane, 3- (isopropylamino) propylamine, 1-cyclohexylamino-3-amino Propane, 1,4-diaminocyclohexane, 1.3-diaminocyclohexane, Isophorondi amine, 2-methylpentamethylenediamine, 2.2.4 (2.4.4) trimethylhexamethyl lendiamine, hexamethylenediamine, N-aminoethylpiperazine, triethylene tetramine.

As the N, N'-disubstituted diamine component used for the invention in accordance with curable epoxy resins is an essential part second diamonds, which are well known in the Be prepared in two stages, in the 1st stage the Diamine (with 2 primary amino groups) with an aldehyde or ketone, such as Acetaldehyde, propionaldehyde, isobutyraldehyde, methylethyl ketone, diethyl ketone, methyl isobutyl ketone or 2-ethylhexanal is set and in the 2nd stage the Di-Schiff base on one Co-contact is hydrogenated at 125 ° C and 30 bar. The production sol cher compounds is described in DE-OS 29 51 603, p. 9.  

When used for the reaction with the aldehydes or ketones Diamines are aliphatic diamines from 2 to 18 C atoms, such as. For example, ethylenediamine, hexamethylenediamine, 2-methyl pentamethylenediamine, 2.2.4 (2.4.4) trimethylhexamethylenediamine. Wei terhin come for the inventive curable epoxy resins as disecondary diamines, such diamines in question, by reaction of 1 Mol diamine with 2 moles of a monofunctional glycidyl ether erhal be:

where R is an optionally alkyl-substituted alkylene radical having 2 to 18 C atoms and R ^{1 is} an alkyl radical having 1 to 20 C atoms. The reaction of the two components is carried out so that the glycidyl ether is added dropwise to the diamine at about 100 ° C so that the temperature of the reaction mixture does not rise above 130 ° C.

But one can also start from difunctional glycidyl ethers, the then be reacted with primary monoamines:

wherein R ^{2 is} an alkylene radical having 2 to 40 carbon atoms, wherein at least one methylene group may be replaced by O and R ^{3 is} a C ₄ -C ₂₀ - alkyl radical, wherein one or more methylene groups may be replaced by O atoms.

Another possibility for the preparation of the inventive ßen curable EP resins necessary disekundären diamine component consists by reaction of 1 mole of diamine with 2 moles of acrylonitrile or Acrylic acid tert-butyl ester:  

To the heated to 70 ° C diamine, the acrylic acid derivative is so dosed that the temperature of the reaction mixture is not above 100 ° C. increases. After completion of acrylonitrile or acrylic acid tert-butyl ester addition, the reaction mixture for a further 2-3 h at 70 ° C on heated.

It is known that in the partial replacement of a polyamine by a monoamine flexural strength and impact resistance of the thus hardened epoxy resins are significantly improved. So z. B. in partial replacement of diethylenetriamine by n-butylamine, the flexural strength improved by 20% and the impact strength by at least 300% (L. Csillay, G. Sztanky, Kunststoffberater 20 (1975), 11, 652-653). With such a mixture (diethylenetriamine, n-butylamine + equivalent amount of epoxy resin), however, can not be flexible plates with z. B. 50% and more elongation at a Zugfe strength of 10 to 20 N / mm ² achieve.

It was surprising that by adding Butylbenzolsulfonsäureamid the preparation of such flexible structure was made possible, considering that the forth conventional methods of external softening on epoxy resins only be are applicable. Apart from the bad tolerable keit the amine-cured epoxy resins with the usual softening in the exudation of the softener from the cured resin is, by the addition of Weichmachungsmit elasticity hardly improves, but the structural strength significantly worsened. Even more surprising was that the invented curable epoxy resins according to the invention after 7 days of curing at Raumtem temperature of those of DE-OS 31 51 592 with respect to the gasoline resistant are far superior. For the preparation of the ready to use Mi The individual components in the epoxy resin are added to the epoxy resin  biger order added. Catalysts for accelerating the Curing can also be used. There are those in the Epoxy resin chemistry known accelerator into consideration, such as. B. the Reaction products of (substituted) phenol with formaldehyde and Ammonia. Other catalysts are salicylic acid, p-toluenesulfone acid methyl ester, phenylurea. The additional amounts are 0.5 to 4%, based on the curable epoxy resin mixture.

The mixtures according to the invention are suitable for coatings and casting resins, which, as already mentioned, have particular elasticity arrives, such as B. roofing and floor coatings. Furthermore, can Coatings with the inventive mixtures for wear protection on metals. Flexibility like strength can at a given polyamine / disecondary diamine ratio are arbitrarily selected by the BBSA amount, with increasing amounts At BBSA an increase in elongation (in%) with simultaneous decrease mean the tensile strength. If you strive for high strains, that's it appropriate, as polyamine 2.2.4 (2.4.4) -Trimethylhexamethylendiamin or 2-methylpentanediamine-1.5 and as disecondary diamine the reac tion product of 1 mole of hexanediol diglycidyl ether and 2 moles of 2-ethyl use hexoxypropylamine. The mixtures according to the invention can be usually after a short mixing time - 5 minutes are completely sufficient - apply and cure at room temperature sticky free with flawless surfaces. When using low mols kularen polyamines, such as. For example, ethylenediamine, diethylenetriamine and 2-methylpentamethylenediamine, it can in short mixing time however come to flow problems. These surface defects can be avoided, however, if the polyamine or the Polyamine / disecondary diamine mixture with a part of for curing required amount of epoxy resin is reacted.

example 1

1140 parts by weight an epoxy resin based on bisphenol A and epichloride hydrin with an EP value of 0.53 were mixed with 158 parts by weight. 2,2,4-  (2.4.4) -Trimethylhexamethylenediamine (TMD), 550 parts by weight. a reac tion product of 1 mole Hexandioldiglycidylether and 2 moles 2-ethylhexylamine

and a) 200 parts by weight, b) 300 parts by weight, c) 400 parts by weight. BBSA and in each case a) -c) 3 parts by weight. Tris-dimethylaminomethyl-phenol (DMP 30), based on the Σ hardener + resin, were mixed thoroughly with one another and, after about 5 minutes, poured into plates of 4 mm thickness and allowed to harden at 25 ° C. The hardness increase (Shore hardness according to DIN 53 505 and after 7 days hardening at 25 ° C tensile strength σ (N / mm ² , elongation ε (%) (DIN 53 455) and the tear propagation resistance WR (N / mm) (DIN 53 515 ) were set.

The hardened mass is clear-transparent and tack-free. The gemes These data are averages of three exams each in one Table summarized.

The test of the following examples was described as in Example 1 ben performed.

Example 2

1140 parts by weight an EP resin based on bisphenol A and epichloride hydrin with an EP value of 0.53, 158 parts by weight. TMD, 666 parts by weight. a reaction product of 1 mol of hexanediol diglycidyl ether and 2 moles of 3- (2-ethylhexoxypropyl) amine, a) 300 parts by weight. BBSA, b) 250 Pw BBSA, c) 200 parts by weight. BBSA, d) 150 parts by weight. BBSA, e) 100  Pw BBSA and 3 parts by weight each. DMP 30 were used in analogy to Example 1 cured.

Example 3

1140 parts by weight an (aliphatic) diglycidyl ether with a EP value of 0.5, 158 parts by weight. TMD, 550 parts by weight. a reaction pro from 1 mole of hexanediol diglycidyl ether and 2 moles of 2-ethylhexyl amine, a) 300 parts by weight BBSA, b) 200 parts by weight. BBSA, c) 100 parts by weight. BBSA and in each case 3 wt .-% DMP 30 were in analogy to Example 1 out hardened.

Example 4

1140 parts by weight of the epoxide from Example 3, 158 parts by weight. TMD, 666 Pw a reaction product of 1 mole of hexanediol diglycidyl ether and 2 moles of 2-ethylhexoxypropylamine, 200 parts by weight. BBSA and 64.9 Pw DMP 30 were cured in analogy to Example 1.  

σ 6 ε 113 WR 17.2 Shore A (3 sec) 73

Example 5

1140 parts by weight of the epoxy resin from Example 1, 158 parts by weight. TMD, 222 Pw a reaction product of 1 mole of 2-methylpentamethylene diamine and 2 moles of acrylonitrile, a) 550 parts by weight. BBSA, b) 600 parts by weight. BBSA and in each case 3% by weight of DMP 30 were prepared analogously to Example 1 hardened.

Example 6

1140 parts by weight of the epoxy resin from Example 1, 158 parts by weight. TMD, 414 parts by weight. a reaction product of 1 mole of TMD and 2 moles of tert-butyl acrylate, a) 500 parts by weight. BBSA, b) 600 parts by weight. BBSA and 3 wt .-% DMP 30 were cured in analogy to Example 1.

Example 7

1140 parts by weight of the Ep resin from Example 1, 116 parts by weight. 2-methyl pentamethylenediamine (MPDA), 372 parts by weight. of a reaction product 1 mole of MPDA and 2 moles of tert-butyl acrylate, a) 500 parts by weight. BBSA, b) 600 parts by weight. BBSA and 3 wt.% DMP each were prepared in Ana For example, 1 cured.

Claims (2)

1. curable epoxy resins having more than one epoxy group per molecule, which cure at room temperature, characterized in that the curing agent is a polyamine / disecondary diamine mixture, starting from

• a1 1 mol (cyclo) aliphatic polyamine having at least 3 active H atoms per molecule and
• a2 0.25 to 4 moles disecondary diamine of the formula wherein R = is a branched or unbranched, optionally substituted with 1-2 OH groups (cyclo) -alkylene with 2-18 C-Ato men, and one or more methylene groups by O atoms he can be sets; R 'is a branched or unbranched, where appropriate, with 1-2 OH groups substituted alkyl radical having 3-20 carbon atoms, and one or more methylene groups may be replaced by O atoms; or R ' means together with
• b 50 to 350 wt .-%, based on the curing agent mixture of N-butylbenzenesulfonamide is used.

2. Curable epoxy resins according to claim 1, characterized, that usual fillers, pigments and reaction accelerators too be set.