DE2748705A1 - ADDITIVE FOR AMINE-CURED EPOXY RESIN COMPOSITIONS AND A PROCESS FOR THE PREPARATION OF CURED EPOXY RESINS USING THE ADDITIVE - Google Patents

Abstract

Cured epoxy resins of high adhesive strength are prepared by curing a mixture containing a vicinal polyepoxide having an epoxy equivalent weight of greater than 1.8, a polyamine as curing agent, optionally a curing accelerator and a polyethersuccinimide or -ureide containing terminal amino groups having a molecular weight of from 4000 to 4500.

Description

Additive for amine curable epoxy resin compositions as well

a method of making cured epoxy resins using of the additive.

The invention relates to an additive for amine curable epoxy resin compositions and a process for the production of cured epoxy resins with improved Adhesion strength using the additive.

Epoxy resins form a large class of polymeric materials that make up a includes a wide range of properties. The resins are characterized by epoxy groups, the epoxy resin compositions cured by reaction with certain catalysts or hardeners are curable with certain desired properties. Such a class of hardeners are the amines. The amines most frequently used as hardeners are aliphatic Amines such as diethylenetriamine, triethylenetetramine and the like and / or polyoxyalkylene poly2: nine such as polyoxypropylene diamines and triamines.

Epoxy resins with improved mechanical properties are made by Use of polyoxialkylenepolyamines, in particular polyoxialkylenediamines as Get harder. It is common to use a co-hardener in such epoxy resin compositions, as described in US Pat. No. 3,549,592. to use.

It is known from aliphatic or aromatic amines and 2-basic Acids or anhydrides to form oligomers (see US Pat. No. 3,732,189). Furthermore were Diamines reacted with maleimides or anhydrides to form elastomers (US Pat. No. 2,818,405). Thermosetting raw materials are also made from epoxides and certain N-containing compounds terminated with carboxyl groups (see U.S. Patent 3,984,373).

Various ureas are also known as epoxy hardeners or co-hardeners and substituted ureas. In this regard, reference is made to U.S. Patents 3,294 749, 2,713,569, 3,386,956 and 3,386,955, 2,855,372 and 3,639,338. the Urea compounds disclosed in these patents are used as hardeners and suitable as a hardening accelerator.

The invention is based on the object of an additive for with amine curable epoxy resins to create cured products with significantly improved Bond strength and shear strength leads. There should also be a method of manufacture of cured epoxy resins with this additive.

The object is achieved by an additive for epoxy resin compositions curable with amine, which is characterized by the general formula (I) in which mean: XA or B, where A is -C = 0 or a radical of a difunctional isocyanate with two -N = C = o groups and B is the radical Z is an alkylene radical with 2 to 5 carbon atoms; YH, methyl or ethyl; m and n are numbers such that the molecular weight of the additive is about 4,000 to 4,500; and H, a straight-chain or branched alkyl radical having 1 to 10 carbon atoms, a monocyclic aryl, alkaryl or aralkyl radical having 6 to 12 carbon atoms, a straight-chain or branched alkenyl or alkadienyl radical having 2 to 10 carbon atoms or a Aninoalkylamine radical of the formula NH (CH,) p NH2, in which p 2 or 3 it.

The additives according to the invention can be referred to as polyoxyalkylenes with terminal amino groups and, if I is X A in the general formula, one Ureylene bridge, or if X is B, at least one succinimide bridge. Below For the sake of brevity, the term polyether-ureylene or polyether-succinimide is used.

That the incorporation of these compounds as additives in epoxy resin compositions leads to hardened products with improved shear strength and adhesive strength, was surprising, especially since compounds of a similar type but lower molecular weight do not bring this effect. Those cured with the additives according to the invention Resins are suitable as coatings, castings, seals and especially as adhesives.

Generally speaking, the adhesive strength (adhesive property) of amine-hardened ones Epoxy resins by adding an effective amount of a polyether terminated Amino groups and ureylene or. Succinimide bridges and a molecular weight of about 4000 to 4500 improved considerably. According to one aspect of the invention, the terminal amino groups primary, after another secondary.

Preferably, a diglycidyl ether of 4,4'-isopropylidenebisphenol, an amount of a hardener bearing primary amino groups sufficient for hardening, which consists essentially of a polyoxypropylene polyamine having a molecular weight of about 20C to 500, a piperazine alkanolamine accelerator and an effective one Amount of the additive according to the invention mixed together and cured.

According to the invention, a polyepoxide, an amine hardener, a polyether with terminal amino groups and a ureylene or.

Succinimide bridges and, if desired, an accelerator carefully mixed and hardened by conventional methods.

Cured products with surprisingly high adhesive strength are obtained.

According to one embodiment of the invention, a diglycidyl ether of 4,4'-isopropylidene-bisphenol with an effective amount of a hardener and des additive according to the invention, namely a polyether ureylene or succinimide with terminal amino groups and a molecular weight of about 4000 with each other mixed and hardened. The preferred polyether-ureylene is made by reacting about 2 moles of polyoxypropylenediamine having a molecular weight of about 2000 with a Moles of urea, that polyether succinimide by reaction of 2 moles of the polyoxypropylenediamine made with about one mole of maleic anhydride. A polyoxypropylene polyamine a molecular weight of about 200 to 500 can be added as a co-hardener.

The cured epoxy resins are preferably produced in 3 stages: In the 1st stage the additive is produced. To do this, about 2.0 moles a polyoxypropylene polyamine having a molecular weight of about 2000 which is essentially Polyoxypropylenediamine is placed in a suitable reaction vessel. Then you give 1 mol of urea or maleic anhydride. After that, it is gradually heated at Add urea to around 180 to 200 ° C and maintain the temperature as long as until the ammonia development stops. If you have added maleic anhydride, is heated to 140 to 170 OC until the aeotropic removal of water ends is. The reaction mixture is then heated to 120 to 150 OC or 170 to 190 OC (the latter in the case of polyether succinimide production) and 1.33 mbar stripped and a viscous Get liquid.

In the 2nd stage, the viscous liquid of stage 1 with a Polyoxypropylenediamine having a molecular weight of about 200 to 250 in ratio from about 5: 1 to about 1: 5 mixed.

A commercially available accelerator can be added to this mixture, if desired be admitted.

The mixture of stage 2 is given a suitable narrow one in stage 3 Diglycidyl ether of 4,4'-isopropylidene-bisphenol added, so that the 8min equivalent e are equal to the epoxy equivalents. The epoxy resin and the Hardener mix are mixed carefully; this will take about 3 drops of a liquid Silicones added to avoid the formation of bubbles and voids. The resulting Composition is applied to substrates after degassing under vacuum for 2 to 5 minutes applied to glue it or poured into molds. The resins are at Cured at room temperature and preferably post cured at about 80 to 125 ° C. the hardened products have improved shear strength, flexural strength, elongation at break and in particular, improved adhesion to the substrate.

In general, the compositions are vicinal polyepoxides and which are hardened with amine, organic materials with average at least 1.8 reactive 1,2-epoxy groups in the molecule. These polyepoxides can be monomeric or polymeric, saturated or unsaturated aliphatic, cycloaliphatic, aromatic or heterocyclic compounds, in addition to the epoxy groups as well other substituents such as hydroxyl, xther radicals, aromatic halogen and the like can carry.

Preferred polyepoxides are those of glycidyl ethers made by Epoxidizing the corresponding allyl ethers or in a manner known per se Reacting a molar excess of epichlorohydrin with an aromatic polyhydroxi compound, z. B. Isopropylidene bisphenol, novolak, resorcinol, etc. The epoxy derivatives of methylene and isopropylidene bisphenol are preferred. For the process according to the invention Suitable polyepoxides include the resinous epoxy polyethers that are produced by reaction an epihalohydrin such as epichlorohydrin with either a polyhydric phenol or a polyhydric alcohol. Examples are: 4,4'-isopropylidene bisphenol, 2,4'-dihydroxidiphenylethyl methane, 3,3'-dihydroxidiphenyl diethyl methane, 3,4'-dihydroxidiphenylmethylpropyl methane, 2,3'-dihydroxidiphenylethylphenylmethane, 4,4'-dihydroxidiphenylpropylphenylmethane, 4,4'-dihydroxidiphenylbutylphenyl methane, 2,2'-dihydroxidiphenylditolyl methane, 4,4'-dihydroxidiphenyltolylmethyl methane and the same. More polyhydric phenols, in particular with an epihalohydrin can be implemented are, for. B. resorcinol, hydroquinone, substituted hydroquinones, z. Methylhydroquinone, and the like.

Among the polyhydric alcohols that interact with an epihalohydrin too lead to the resinous epoxy polyethers, include compounds such as ethylene glycol, Propylene glycols, butylene glycols, pentanediols, bis (4-hydroxycyclohexyl) dimethyl methane, 1,4-dimethylol-benzene, glycerine, 1,2,6-hexanetriol, trimethylolpropane, mannitol, Sorbitol, erythritol, pentaerythritol, their dimers, trimers and higher polymers, z. B. polyethylene glycols, polypropylene glycols, triglycerol, dipentaerythritol and the like, polyallyl alcohol, polyhydroxy thioethers such as 2,2'-, 3,3'-tetrahydroxidipropyl sulfide and the like, mercapto alcohols such as monothioglycerin, dithioglycerin, and the like, Partial esters of polyhydric alcohols such as monostearin, pentaerythritol monoacetate and the like and halogenated polyhydric alcohols such as the monochlorohydrins of glycerine, Sorbitol, pentaerythritol and the like.

Another class of polymeric polyepoxides that are amine cured and are suitable for the process according to the invention are the epoxy novolak resins, by reaction, preferably in the presence of a basic catalyst, e.g. B.

Sodium or potassium hydroxide, an epihalohydrin such as epichlorohydrin, with the resinous condensation product of an aldehyde, e.g. B. formaldehyde, and either a monohydric phenol, e.g. B. phenol itself or a phenol with several Hydroxyl groups are obtained. More details about nature and manufacture of epoxy novolak resins can be found in the Handbook of Epoxy Resins by Lee and Neville, McGraw Hill Book Co., 1967.

It will be obvious to those skilled in the art that other polyepoxide compositions can be used for the process according to the invention.

The additives according to the invention can generally be described as polyoxyalkylene-containing materials with a single ureylene bridge or at least one succinimide bridge, terminal amino groups and a molecular weight of about 4,000 to 4,500. The additives fall under the general formula I. in which the individual symbols have the meaning given above. Preferably, when R is a branched or straight-chain alkyl radical, it has 1-6 C atoms; when it is a monocyclic aryl, alkaryl or aralkyl radical, 6-8 carbon atoms; or if it is a branched or straight-chain alkenyl or alkadienyl radical, 3-8 carbon atoms.

The additives according to the general formula are very particularly preferred I, in which R is an alkyl radical with 1-4 carbon atoms or a 1,2-propylamine radical, in particular Hydrogen, Y a methyl radical, Z a 1,2-propylene radical and m and n are the same numbers are from 16-19; Of course, m and n are average values. The preferred Polyether ureylenes are those in which X is -C * 0.

The polyether-ureyls with terminal primary amino groups are by reacting a ureylene-forming compound with a polyoxialkylenediamine a molecular weight of about 1800 and 2200 at about 100 to 200 OC, being the molar ratio of ureylene-forming compound to polyoxialkylenediamine approximately 1: 2.

The polyether succinimides with terminal primary amino groups are by reacting maleic anhydride with a Pclyoxialkylenediamine of one molecular weight manufactured from 1800 to 2200 in 2 stages. First the reactants are at lower Temperature, d. H. Room temperature, mixed and then the crude product to 120-180 OC heated, removing the water with one mole of maleic anhydride.

The diamines which are suitable for producing the additives are polyoxyalkylenediamines of the general formula II in which: Y is hydrogen, methyl or ethyl; Z is a hydrocarbon alkylene radical with 2-5 carbon atoms and n has an average value of 12-20. The preferred polyoxyalkylenediamines are those in which Y is a methyl radical, n is 16-18 and Z is a 1,2-propylene radical. These polyoxialkylenepolyamines can be prepared by known methods, such as those described, for. B.

in U.S. Patents 3,236,895 and 3,654,370.

The polyether-ureylenes can be obtained by reacting a polyoxyalkylene polyamine with alkylene radicals with 2-4 carbon atoms, with urea, a ureylene-forming compound or organic bifunctional isocyanates can be produced. Is preferred Urea.

When urea is used as the reactant, the reaction proceeds with evolution of ammonia and the terminal primary amino group of the polyoxialkylenepolyamine is converted into a ureido group. The functionality of the polyoxyalkylene polyamine depends on the number of terminal primary amino groups. Because urea itself is bifunctional, each molecule can be urea with 2 terminal amino groups of the polyoxialkylenepolyamine react.

Although urea is the preferred reactant, other urea-forming compounds can be used to remove the bridging moiety to deliver. Since the polyoxyalkylenepolyamine already contains terminal primary amino groups, compounds such as carbonyldiimidazole, phosgene or diphenyl carbonate can be used as suppliers to form ureylene bridges without splitting off ammonia.

Another class of Polyätherureylen is made by reacting Polyoxialkylenepolyamines with a bifunctional orange isocyanate, e.g. B. manufactured by phosgenation of the condensation product of aniline and formaldehyde.

Suitable compounds are 4,41-diphenylmethane diisocyanate or its isomers, such as 2,4'-diphenylmethane diisocyanate and mixtures of these isomers.

The polyether succinimides are made by reacting a Polyoxialkylenepolyamine with alkylene radicals with 2-4 carbon atoms with maleic anhydride. The reaction proceeds with the release of water and a terminal primary amino group the polyoxialkylenepolyamine converts to a succinimide group. The maleic anhydride has a bifunctional effect, the ethylenic unsaturation with the terminal amino group linking another polyoxyalkylenediamine.

According to a further embodiment of the invention, polyether-ureylenes are used or -Succinimides with terminal secondary amino groups are used. Preferably these compounds are terminated by reductive amination of the compounds primary amino groups obtained.

The reductive amination of primary amines with aldehydes and Ketones of standard hydrogenation / dehydrogenation catalysts is known and is needed here not to be explained in more detail. Another method of making connections with secondary amino groups excludes the use of organo-halogen compounds a. This method is not preferred because there are too many side reactions.

According to a further embodiment, polyether ureylenes can be used or succinimides with terminal aminoalkylamine residues by cyanoalkylation of polyethers with terminal primary amino groups and subsequent hydrogenation of the cyanoalkylated compounds. The production of cyancalkylated Adducts are described in U.S. Patent 3,666,788. The hydrogenation takes place according to the conventional method Method on a standard hydrogenation / dehydrogenation catalyst.

The polyether ureals and succinimides with terminal primary amino groups can act as amino hardeners on their own. So these connections both practice the function an amine hardener as well as that of an additive, through which the adhesive strength is increased from. However, it is preferred other than these terminated additives primary amino groups the epoxy resin compositions nor a common amine hardener admit.

All common amine hardeners for hardening vicinal epoxides can be used Amines are used. In general, such hardeners are reactive with at least 2 Amino groups suitable. Examples of such amines are alkylene polyamines, such as Diethylenetriamine, triethylenetetramine and the like; Oxialkylenepolyamines, such as polyoxypropylene di- and triamine and diamine derivatives of ethylene glycol, such as 1,13-diamino-4,7,10-trioxatridekan.

In addition, aromatic amines are suitable as hardeners. Examples of this are polyphenylamines, phenylenediamines and polycyclic ones containing alkylene bridges or fused aromatic ring systems with primary amino groups. Also the corresponding ones Cycloaliphatic compounds can be used.

Polyamide hardeners, such as the condensation products, are also suitable of polyamines and polycarboxylic acids. As an example, consider the condensation product of a polyamine and a dimerized fatty acid disclosed in U.S. Patent 2,379,413 used.

Of the amine hardeners which are suitable for hardening vicinal epoxy resins, the polyoxyalkyleneamines of the following general formula II are preferred according to the invention: in which YH, methyl or ethyl, Z is a hydrocarbon radical with 2 to 5 carbon atoms which forms 2 to 4 external Xther bridges, n is a number from 1 to about 15 and r is a number from 2 to 4. At the. Most preferred are the polyoxypropylenediamines, where in formula II Y is methyl, n is a number from 1 to 10, Z is a 1,2-propylene radical and r is about 2. The preparation of these compounds is described in U.S. Patents 3,236,895 and 3,654,370. A polyoxypropylenediamine having a molecular weight of about 230 is very particularly preferred. Another preferred class of polyoxypropylenepolyamines can be represented by the general formula III below in which Y, Z, n and r have the same meaning as in formula II and y or 3 is. These poly (aminoalkylamino) polyethers are the hydrogenation products of the cyanoalkylated adduct of a polyoxialkylenepolyamine as described above. The preparation of these adducts is described in US Pat. No. 3,666,788. The hydrogenated cyanoethylated polyoxypropylenetriamines are preferred.

If desired, the epoxy resin compositions can also contain an accelerator which accelerates the amine curing of the epoxy resin, especially at room temperature. Such acceleration is advantageous for some applications, in particular when an epoxy resin is applied as an adhesive in a flammable environment, what elevated curing temperatures would make inappropriate, if not dangerous. In the above-cited Handbook of Epoxy Resins is on the pages 7 to 14 the use of certain amine-containing compounds as curing accelerators for epoxy resin compositions.

Many accelerators are known which can be used in the method according to the invention can be used. Examples are salts of phenols, salicylic acid, Amine salts of fatty acids as described in US Pat. No. 2,681,901 and tertiary amines, as described in U.S. Patent 2,839,480. The accelerator preferred according to the invention is disclosed in U.S. Patent 3,875,072.

It is a mixture of piperazine and an alkanolamine in a weight ratio from about 1: 8 to 1: 1.

According to the invention, the adhesive strength of the known amine-hardened Epoxy resins by adding an effective amount of a polyether urylene or succinimide terminated with amino groups and having a molecular weight of about 4,000 to 4,500 elevated. The amount of additive needed to increase the bond strength is somewhat empirical and depends on the resin, the use of an amine hardener and the Use of an Accelerator In general, the polyether is terminated with Amino groups, if it is to serve as a hardener / additive, in roughly stoichiometric amounts used.

In conjunction with other known amine hardeners, the inventive Additive preferably in amounts of about 5-40 parts by weight, based on 100 parts by weight. Resin. Whether alone or used with an amine hardener, the exact amount of additive required can easily be found without further experimentation empirically determine based on the fact that a resin mixture, which is an effective Amount of additive contains, undergoes changes which are even more noticeable during hardening become visible. The hardenable resin takes on an opaque michi'g-white appearance, which becomes even stronger on hardening and results in a product with a glossy white appearance leads. This change in optical absorption increases the beauty of castings and eliminates the need for white pigments or fillers.

The ratio of additive and hardener to resin can be determined on an equivalence basis easily determine. The equivalence determination should also identify the functional groups of the Include accelerator.

The amount required can be calculated by adding the number the equivalents on a weight basis per replaceable HN groups in the amine hardener, the A-dditive and, if used, the accelerator. Based on this calculation is a mixture of a polyoxyalkylenediamine hardener, additive and accelerator in 10% excess over the stoichiometristhe required, based on the resin Amount used. According to a preferred embodiment, the adhesive properties a known epoxy resin composition having an epoxy equivalent greater than 1.8 by addition an effective amount of a terminal polyoxypropylene ureylene or succinimide Amino groups obtained by condensation of one-way moles of urea or one mole Maleic anhydride with 2 moles of a polyoxypropylenediamine of molecular weight from 2000, increased. Preferred resin compositions are polyglycidyl ethers of polyphenols, that by incorporating an amount of a polyoxyalkylene polyamine sufficient to cure a molecular weight of 200 to 500 and an accelerator combination of piperazine and an alkanolamine in a weight ratio of about 1: 8 to 1: 1. Preferred known compositions whose adhesive strength is determined by the additives of the invention are disclosed in U.S. Patent 3,943,04.

The curable epoxy resin compositions contain a vicinal polyepoxide an epoxy equivalent weight of more than 1.8, an amount of amine hardener sufficient for curing, an effective amount of the additive of the invention and an accelerator. Even though all epoxy resins specified herein are suitable for the process according to the invention, are those based on aliphatic compounds, preferably not alone used.

The presence of resins, the polyglycidyl ethers of polyvalent Contain phenols in amounts above 50, preferably 80% by weight, in particular resins, which consist of 100% polyglicidyl ethers of polyhydric phenols the desired properties of the cured products, especially the adhesive strength.

In the same way, all amine hardeners can also be used in the case of the invention Process are used. However, it has been found that resins with hardeners, in which, unlike the additives according to the invention, the amino groups through long aliphatic or oxyalkylene chains are separated, viscous and heavy are to be processed and in the presence of the additive according to the invention to products cure, which do not have the desired high adhesive strength. The reason for that is not exactly known, but it is believed that this is due to the compatibility of the components is related.

So show z. B. Resins made with polyoxypropylenediamine of one molecular weight of 400 cured in the absence of otherwise effective amounts of the additive according to the invention no significant improvement in bond strength.

Because of the greater economy and ease of use those amines whose molecular weight is below about 500 are preferred. Preferred Amine hardeners are polyamines of an amine equivalent weight of 20-150, in particular 20-70. Examples of such hardeners are polyoxypropylenediamines of molecular weight in the range of 200 to 300 and polyoxypropylene polyamines of molecular weight in the range from 400 to 700.

Unsuitable amine hardeners can be quickly identified by a specialist, since these hardeners do not bring about any effective visual improvement.

The amine-cured resins with pre-bonded adhesive strength are used in Usually made when an amine hardener is used in addition to the additive the mixture with the polyepoxide composition is in the amine equivalent weight of the mixture in the appropriate amount. In general, the number is of the equivalents of the amino groups about 0.8 to 1.2 times the number of epoxy equivalents in the curable epoxy resin composition, with a stoichiometric amount being preferred will. If an accelerator is used, amounts of 1 will generally suffice Up to about 10 parts by weight, based on 100 parts by weight. Resin. The exact amount of the ingredients depends primarily on the purpose for which the cured resin is intended.

When the additive of the invention is used alone, it will mixed into the uncured resin. If a hardener is also used, mixed the additive is preferably first mixed with the hardener or the hardener-accelerator mixture, before working it into the resin. The components that make up bare material are intimately mixed with one another by the usual methods and more usual in the presence Defoamers degassed, with small amounts of silicones added to the formation to avoid bubbles and voids.

If an accelerator is used, one is preferred, the mixture of piperazine and alkanolamine in a weight ratio of about 1: 8 up to 1: 1. It is preferably used in an amount of about 1 to 5 ow. per 100 Parts of resin incorporated. The accelerator is hardened with a polyoxyalkylenediamine mixed, with about 10-50 parts by weight. Accelerator 100 parts by weight. of the hardener come.

As already said, it may be sufficient to use the Additive to be used as the only hardener. However, it is preferably used in conjunction with a customary amine hardeners for epoxy resins, as listed above, are used. Polyoxialkylenediamines of the type described above which have one amine equivalent from 20 to 70, preferably from 40 to 70, are preferred as co-hardeners. It it has been found that ratios of polyether ureylene or succinimide to Amine (-Co) hardeners from about 5: 1 to about 1: 5 epoxy resins with considerably improved Properties, e.g. B. shear strength, flexural strength, elongation at break and in particular Give adhesive strength.

The mixture of epoxy resin, polyoxyalkylene polyamine, additive and accelerator combination from piperazine and alkanolamine are generally left at room temperature (between 0 and 45 OC) harden yourself. Post-curing at elevated temperature up to about 135 OC has proven to be inexpensive.

According to a preferred embodiment of the invention, a diglycidyl ether of 4,4'-isopr; opylidene-bisphenol, an amount of a primary sufficient to harden Amino-group-containing hardener, which consists essentially of a polyoxypropylenediamine a molecular weight of about 200 to 250, an accelerator of piperazine and triethanolamine in a weight ratio of 3: 7 and an effective amount of an additive with terminal amino groups and a molecular weight of about 4000 and hardened.

According to a preferred embodiment, polyglycidyl ethers are from polyhydric phenols by incorporating a polyoxyalkylene polyamine of one molecular weight from 230 in an up to stoichiometric amount, about 5 to 30 parts by weight. one according to the invention Additive and 1 to 5% by weight, based on 100 parts by weight of resin, of an accelerator mixture hardened from piperazine and triethanolamine (3: 7). The hardening takes place at room temperature instead and you get products with improved adhesive strength.

Other customary additives can of course also be added to the composition be incorporated before hardening. So it can be B. useful in certain cases be, small amounts of other polyalkyleneamine CO catalysts, as described above, or hardeners along with various other accelerators and known curing systems to add.

Customary pigments, fillers and flame retardants can also be added and the like that are compatible with the other ingredients of the composition as well as natural and synthetic resins.

Although not preferred, those known for polyepoxides can also be used Solvents can be used, such as toluene, benzene, xylene, dioxane, ethylene glycol monomethyl ether and the same.

The polyepoxy resins containing the additives according to the invention can be used wherever polyepoxides have been used up to now. A special feature of the compositions is that they are opaque after curing and have a smooth white glossy surface, which is particularly beneficial for moldings and castings. The compositions obtained according to the invention Can be used for impregnation, surface coating, egg capsules, lamination and before mainly used as an adhesive for metal / metal.

The invention will now be explained by means of examples.

Example 1 Preparation of a polyether ureylene with terminal amino groups according to the invention.

In a suitable reaction vessel equipped with a stirrer (POPPA) was 28.5 kg (0.032 mole) of a polyoxypropylene diami (molecular weight 2000 and 1.0 milliequivalent (meq.) primarily amine / g) and 0.45 kg (0.016 mol) urea. The mixture was purged with nitrogen and placed under a nitrogen blanket touched, while gradually heating to 183 ° C. This mixing temperature was maintained until the ammonia development ceased. The resulting crude reaction product was then stripped at 150 ° C. and 1.33 mbar and obtained a viscous liquid. This Product was then filtered through a filter cloth. The analysis showed: 1.57% N, 0.53 meq total Xmin / g, 0.52 meq primary knin / g, 0.10% water.

Example 2 Preparation of a terminal polyether succinimide Amino groups according to the invention.

In a suitable, clean, dry reaction vessel equipped with a stirrer, Thermometer, reflux condenser and Dean-Stark trap were provided, 750 g (0.39 Moles) of POPPA 2000, 18.4 g (0.183 moles) of maleic anhydride and 50 g of benzene were added. This mixture became about 2 1/4 at reflux (vessel temperature 146 to 167 ° C) Heated until the azeotropic removal of the water (2.3 g of water) was complete. Then the benzene was removed from the crude reaction mixture until the kettle temperature Was 205 ° C. The remaining reaction product was then at 180 ° C and 3.99 Stripped mbar and a viscous residue obtained, the analysis of which showed: 0.64 meq Total amine / g, 0.43 meq primary amine /, 0, OC9 meq acidity / g. The IR analysis showed the presence of a succinimide group.

To show the advantages of the polyether additives according to the invention, have disclosed various epoxy resin compositions using the diglycidyl ether of 4,4'-isopropylidenebisphenol hardened with various known amine hardeners. An accelerator was also added where appropriate.

Three drops of silicone were added to each batch to ease the formation van to avoid bubbles and voids. After degassing under vacuum, the Compositions cured under the specified conditions. The hardened products were subjected to the ASTtl tests listed below.

ASTM D 256 Izod impact strength ASTM D-790-66 flexural strength and Young's Modulus ASTM D-638-64 T Tensile Strength and Elongation at Break ASTM D-648-56 Heat distortion temperature ASTM 2240-64 T hardness and / or Shore D hardness ASTM D-903 Peel Strength The tensile shear strength according to ASTM D-t002-64 was determined on bonds certainly. All substrates were aluminum plates (mine. 2024-T-3 alloy, 16 gage), degreased, then etched with chromic acid and only then glued.

Example 3-5 In these examples, epoxy resins were made at those glycidyl ethers of 4,4'-isopropylidenebisphenol with a polyoxypropylenediamine a molecular weight of 230 and an equivalent weight of 58 to which the specified Amounts of polyether-ureylene of Example 1 had been added, were cured The resulting resins have been used to bond aluminum to aluminum and the resulting bonds subjected to the ASTM tests. The data that only too To serve comparison purposes, are summarized in Table 1.

Table I Example 3 4 5 parts by weight.

Epoxy (eq. 190) 100 100 100 Hardener 1) 30 29 30 Accelerator 2) AO 10 10 polyether-ureylene 3) --- 29 14 Tensile shear strength, bar curing conditions 24 h 98 112 161 48 h 70 154 231 72 h 98 168 210 96 98 217 259 7 days 105 227 273 72 h, 30 days 5) 112 203 238 72 h, 30 days 6) 126 245 266 1) polyoxypropylidenediamine, MG 230 2) Piperazine-triethanolamine mixture (30:70) 3) Product of Example 1 4) C hardens at room temp.

5) After hardening, immersed in water for the specified time 6) After After curing, the specimens were placed in a weathering apparatus for the specified time; Cycle: full light, 18 min. Water spray / 2.

This example shows the improved adhesive strengths of the epoxy resin compositions, if quantities of polyether-ureylene with terminal amino groups lem polyoxypropylenediamine hardener have been admitted.

Example 6-9 In these examples, epoxy resins were made at those clycidyl ethers of 4,41-isopropylidenebisphenol with a polyoxypropylenediamine a molecular weight of 230 and an ether equivalent weight of 58, think The specified amounts of poly-succinimide from Example 2 had been added, The resulting resins were used to bond aluminum to aluminum used and the resulting bond subjected to ASTM tests. The data, which are only intended to be used for loan purposes are listed in Table 2 example II Examples Composition (parts by weight) 6 7 8 9 Epoxy (Xq. 190) 100 100 100 100 Hardener 1) 30 30 30 30 Accelerator 10 10 10 10 Polyether-Succinimide 2) 0 75 14 29 Tensile shear strength, bar 3) 87 270 288 232 Peel strength kg / cm 1.37 1.82 4.18 6.91 1) Piperazine-triethanolamine mixture 2) Product of Example 1 3) Curing conditions: Room temperature, 7 days These examples show the improved bond strengths of the epoxy resin compositions when amounts of the polyether succinimide terminated Amino groups have been added to the polyoxypropylenediamine hardener.

Examples 10-13 In these examples the polyether ureylene was made from Example I added in different amounts to amine hardener systems. In this 4th Examples were a polyoxypropylenediamine having a molecular weight of 400 and a Amine equivalent of 105 used. The results are shown in Table 3.

Table III Examples Composition 10 11 12 13 (wt / part) epoxy resin, (Xq. 190) 100 100 100 100 hardener 28 49 54 55 polyether-ureylene) 250 49 13 -0-tensile shear strength, bar 21 133 238 273 1) Product of Example 1 2) Hardened: 2 h at 80.degree. C., 3 h at 125.degree. C. These examples show that this additive with regard to the Improving bond strength is less effective when used in resins whose polyether polyamine hardener has an equivalent weight over 70.

Example 14 This example demonstrates the use of the additive Example II in connection with various amine hardeners. The composition is can be found in table 4.

Table IV Composition Example Part by weight. 14 epoxy resin (Xq. 190) 100 hardener 57 additive 1) 24 accelerator 2) 10 appearance of the casting after the Cure 24 h, room temperature opaque, white 3 h, 125 OC opaque, white 1) Product of the example 1 2) Piperazine-triethanolamine mixture The opaque appearance of the castings after Hardening indicates improved bond strength properties.

Examples 15-17 In these examples the polyether ureylene was used with Terminal amino groups from Example 1 added to an epoxy resin system, which is a Polyamidopolyamine (VERSAMID 140) contained as hardener. the properties of the cured products are shown in Table 5. These examples show the improvement of the adhesive strength that the additive has over the polyamido polyamine alone brings.

Table V Composition (Cew.Tle) Examples 15 16 17 Epoxy resin, (Aq. 190) 100 100 100 hardener 40 40 40 polyether-ureylene) t-- 5 10 2> accelerator ) 10 10 10 Tensile shear strength, bar under curing conditions 3) 96 132 218 1) Product of Example 1 2) Piperazine-alkanolamine mixture (30:70) 3) Cured at room temperature Examples 18-23 In these examples the additive according to the invention was used from Example 1 added to an epoxy resin system with triethylenetetramine at room temperature has been hardened. For comparison, the same system was used under the same conditions but hardened without the addition of additives. The composition and properties of the cured resins are shown in Table VI. The resins that make up the additive contain significantly better adhesive properties.

Table VI Composition Examples (parts by weight) 18 19 20 23 Exoxy resin, (Eq. 19) 100 100 100 100 triethylenetetramine 10 10 10 10 polyether-ureylene, 1) - 5 10 20 Tensile shear strength, bar 2) under hardening conditions 18 19 20 23 57 83 129 111 1) Product of example 2) C hardens at room temp.

Example 24 In this example, a polyether terminated ureylene was used Amino groups but lower molecular weight used to have the surprising effect of the material's higher molecular weight.

First, a material was prepared as in Example 1 to be a polyoxyalkylene material with ureylene bridges and terminal di-primary amino groups and a molecular weight of about 800 to get.

This material was then incorporated into the resin as used in Example 4 was incorporated. The resulting resin was poured into separate containers. One half was cured at room temperature, the other half at an elevated temperature. The results are shown in Table VII.

Table VII Composition Examples (parts by weight) 24 epoxy resin (eq. 190) 100 Additive 14 Hardener 28 Appearance of the castings after curing for 24 hours at room temperature clear 3 h at 125 ° clear The above example shows the lack of adhesive properties in the absence of optical improvement.

Example 25 In this example, the additive from Example 1 was used in various amounts incorporated into an amine-hardened system. In the following experiment became a polyoxypropylenediamine having a molecular weight of 400 and an amine equivalent used in about 70.

The results are shown in Table VIII.

Table VIII Composition Example (parts by weight) 25 epoxy resin (Xq. 190) 100 hardener 1) 40 polyether-ureylene 2) 10 Appearance of the casting after hardening 24 h at room temp. opaque, white 3 h at 125 OC opaque, white 1) polyoxypropylenetriamine 2) Product of Example 1

Claims (1)

Claims 1. Additive for epoxy resin compositions curable with amine, characterized by the general formula I. where: XA or B, where A is -C = 0 or a radical of a difunctional isocyanate with two -N = C = O groups and B is the radical Z is an alkylene radical with 2 to 5 carbon atoms; YH, methyl or methyl; m and n are numbers such that the molecular weight of the additive is about 4,000 to 4,500; and RH, a straight-chain or branched alkyl radical with 1 to 10 carbon atoms, a monocyclic aryl, alkaryl or aralkyl radical with 6 to 12 carbon atoms, a straight-chain or branched alkenyl or alkadiengyl radical with 2 to 10 carbon atoms or a Aminoalkylamine radical of the formula - NH (CH2) p NH2, in which p is 2 or 3, 2. Additive according to claim 1, characterized by the fact that in the general formula IRH given in claim 1, an alkyl having 1 to 4 carbon atoms or 1 , 2-aminopropyl; Y is methyl and Z is 1,2-propylene and m is n and is a number from 16 to 19. 3. Process for the production of cured epoxy resins with improved Adhesion strength using an additive according to claim 1, characterized in that that a vicinal polyepoxide of an epoxy equivalent weight above 1.8, one for curing sufficient amount of a polyamine and possibly. A curing accelerator with at least 3 reactive amino H atoms mixed with the additive and the mixture in known Way is hardened. 4. The method according to claim 3, characterized in that the mixture an additive according to claim 2 is incorporated. 5. The method according to any one of claims 3 and 4, characterized in that that a polyepoxide, more than 80 wt. From a polyglycidyl ether of a polyvalent Consists of phenol; a polyoxyalkylenepolyamine in such an amount that to 1 epoxy equivalent 0.8 to 1.2 amino equivalents come; and a mixture of piperazine as an accelerator and an alkanolamine in a weight ratio of 1: 8 to 1: 1 can be used. 6. The method according to any one of claims 3 to 5, characterized in that that as an epoxy resin a polyglycidyl ether of a polyhydric phenol and as a hardener a polyoxyalkylene polyamine having an amine equivalent weight of 20 to about 70 is used will. 7. The method according to any one of claims 3 to 6, characterized in that a polyoxyalkylene polyamine of the general formula II as the hardener is used, in which: YH, methyl or ethyl Z is a hydrocarbon radical with 2 to 50 atoms, which form 2 to 4 external ether bridges, n is a number from 1 to about 15 and r is a number from 2 to 4 8. Method according to one of claims 3 to 6, characterized in that a polyoxyalkylene polyamine of the general formula III is used in which X, Z, n and r have the same meaning as in formula II of claim 7 and y is 2 or 3. 9. The method according to any one of claims 3 to 8, characterized in that that a diglycidyl ether of 4,4'-isopropylidene-bisphenol polyepoxide, a polyoxypropylenediamine a molecular weight of about 200 to 250, as an accelerator a mixture of 3: 7 weight ratio of piperazine and triethanolamine and an effective amount of an additive according to claim 1 having a molecular weight of about 4,000 will. 1O.Verfahren according to any one of claims 3 to 8, characterized in that that the hardener is used in an amount so that on 1 epoxy equivalent 1 amine equivalent of the plyepoxide comes, the accelerator in an amount of 1 to 5 parts by weight per 100 parts by weight of polyepoxide and the additive in an amount of about 5 to 40 parts by weight per 100 parts by weight of polyepoxide are used.