DE1595749A1 - Hardening agent for epoxy resins - Google Patents

Description

"Curing agent for epoxy resins"

The invention relates to certain aorylamide adducts of certain cyclic polyamines and the use of these adducts for curing epoxy resins.

The polyamines which can be used according to the invention include the cyclic aliphatic and aromatic polyamines, which are at least have three exchangeable hydrogen atoms. Typical polyamines that can be used according to the invention include 1.4-Cyclohexy ibismethylamine, 1.4-Oyclohexylbisäthylairin, 1,4-Benzolbismethylamine, 1,4-Benzolbisäthylamin, Piperazine and Aminoethylpiperazine and mixtures thereof. When these compounds are converted into the diacrylamide adducts, ask they are excellent curing agents for epoxy resins. The rate of reaction with epoxy resins is such that it is possible to use the diacrylamide adducts of the invention to combine with epoxy resins to form a homogeneous melt

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DIPL-INQ. DIETER JANDES Mt INQ. MANFRED BONINQ -j EJCJCTAQ PATENT LAWYERS

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and the mixture, immediately or after a desired amount of Partial reaction has been achieved to deter. The resulting quenched mixture or partially reacted The combination will then quickly cure completely as soon as the temperature is increased again. You take this point of view are the acrylamide adducts of cyclic aliphatic polyamines, such as 1.4-GyclohexylbismethylaBiin, 1.4-Cyclohexylbisäthylamin, Piparazine and Aminoäthylpiperain preferred. Their responsiveness with respect to epoxy resins is generally somewhat lower and the preparation of mixtures or partial reacted combinations is achieved with less difficulty and the mixtures obtained or partially reacted Combinations cure relatively quickly, but not so quickly that they cause difficulties in handling. Where a particularly fast-curing system is sought, the Aerylamiri adducts according to the invention of the aromatic Polyamines can be used or the same can be used with the acrylamide adducts of cyclic aliphatic polyamines are mixed, so as to achieve medium curing speeds the systems to achieve.

Under "B stage" is a partially cured intermediate stage au understand where the two reaction participants are homogeneous are compatible in a stable single phase preparing for final cure at elevated temperatures is. The hardening of epoxy resins can be achieved by going through three stages, namely A, B and C. The "AtStufe" represents a simple mixture or mixture of the -d £> oxy-resin and the horticultural agent, where practically none Reaction occurs. In the case of the hardening agents according to the application such a simple mixture or mixture will remain stable for a long time.

The "B-stage" is the same mixture that has been partially reacted or cured and is stable for extended periods of time. The ^B B ~ stage ⁿ resin can be cured at elevated temperatures to form the finally hardened stage, the "C stage ^M , which is an insoluble and infusible polymer.

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DIPL-INC- DIErER JANDER DR.-INQ. MANFRED BONINQ -j C QC η Α Q PATENT LAWYERS

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"B-stage ¹¹ resins are by means of a mixture of the two ingredients prepared heating, so as to effect a partial cure and breaking of such a curing gate reaching the ^M C-Step ^H. This partial curing can be carried out at different temperatures. At higher temperatures results in a brief heating, while the heating time slightly long at lower temperatures, and the control is easier. in general, it is preferred to cure the B-stage resins with the novel Härtungemitteln at temperatures IX) O to 150 ⁰ C and this usually requires a period of 15 minutes to 30 seconds.

In addition to the possibility of controlling the useful life of these masses and of obtaining B-stage products, products are also created according to the invention that do not release Cure volatile by-products which tend to form gas bubbles in the hardening resin system.

One of the tasks underlying the invention is thus to find novel acrylamide adducts of certain cyclic to create aliphatic and aromatic polyamines.

Another problem on which the invention is based is to create novel B-stage epoxy compounds that partially cured bit the specified acrylamide adducts of the cyclic aliphatic and aromatic polyamines.

Another problem underlying the invention is to provide a method for curing epoxy resins create using the specified acrylic acid adducts.

In making the acrylamide adducts, approximately two moles of acrylamide per mole of tolyanine are used. With the two Polyamines containing primary amine groups appear to add the acrylamide to each of the primary amine groups so that a propyl amide group on each of the primary amine nitrogens introduced and thus converted into secondary amines. In the pail of compounds, such as aminoethyipiperazine, the acrylamide appears to add 1 mole each to the primary amine and 1 mole to the secondary amine of the ring

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PATENTANWÄLTE '"" "" "* *"

The reaction can be carried out in different ways, but preferably the acrylamide is in a solvent, Dissolved as methanol and the reaction mixture is then brought to reflux temperature. The polyamine is then slowly added and the reaction mixture is kept at reflux temperature, until the reaction is complete. The solvent is then removed by distillation and formation of the final product removed, which in most cases is either solid or semi-solid.

The compounds of the invention are generally useful for curing epoxy resins. These include the following Species.

The epoxy resins useful in making the compositions of the invention include those products which have more than contain a civinal epoxy group, i.e. more than one

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Group. These compounds can be saturated or unsaturated, aliphatic, cycloaliphatic, aromatic or heterocyclic and can optionally be substituted with substituents that do not affect the reaction, such as chlorine, Hydroxyl groups, ether residues and the like. The polyepoxides can be monomeric or polymeric. The epoxy group can be terminal or not be terminal.

For the sake of clarity, many polyepoxides are given below in terms of their epoxy equivalence. The term "epoxy equivalent" refers to the number Epoxy groups contained in the average molecule of the desired compound. The epoxy equivalent "will obtained by dividing the average molecular weight of the polyepoxide by the epoxy equivalent weight. That Epixy equivalent weight is determined by adding one gram of the sample of the polyepoxide with an excess of pyridinium chloride dissolved in pyridine heated at boiling point for 20 minutes will. The excess pyridinium chloride is then added to the phenophthalein endpoint with 0.1 N sodium hydroxide.

ο back-titrated. The epoxy number is then calculated by considering 1 HGl as an equivalent for an epoxy. This Procedure is used to obtain all epoxy numbers as listed here unless otherwise

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DIPL-INQ. DIETER JANDER DR.INQ. MANFRED BONINp A 595749 PATENT LAWYERS

- 5 is noted.

If the polyepoxides are single monomeric compounds, whose epoxy groups are all intact, becomes their epoxy equivalency represent integers such as 2, 3, 4, and 5. In the case of polymeric polyepoxides, however, some of the products contain some of the monomeric monoepoxides or some of their epoxy groups are hydrogenated or otherwise reacted and / or contain macromolecules with slightly different molecular weights, so the epoxy equivalents can be quite low and fractional. Daa polymer «product can e.g. epoxy equivalents such as 1.5, 1 * 8, 2 * 5 and Like. Have.

The monomeric polyepoxide compounds can be represented as follows, for example, t vinylcyclohexene dioxide, epoxidized soya bean oil, butadiene dioxide, 1.4-bis (2.3-epoxypropoxy) benaol, 1.3 ~ bis (2.3-epoxypropoxy) benzene, 4.4 ^l -bis (2,3-Epoxypropoxy-) diphenyl ether, 1.8 -bis (2.3-epoxypropoxy) ootane, 1.4-bia (2.3-epoxypropoxy) cyclohexane, 4.4'-bis (2-hydroxy-3.4-epoxybutoxy) -diphenyldimethylmethane, 1.3-bis (4.5-epoxypentoxy) -5-chlorobenzene, 1.4- bis (3.4-epoxybutoxy) -2-chloroyolohexane, diglyci- ^! dyl ether, 1.3 ~ bis (2-hydroxy-3.4-epoxbutoxy) benaol, 1.4-bis (2-hydroxy-4.5-epoxypentoxy) benzene, 1.2.5.6-di-epoxy-3-hexyne, 1.2.5.6-di-epoxyhexane and 1.2.3.4-tetra (2-hydroxy-3.4-epoxybutoxy) butane.

Further examples of this type include the fflyoidylpolyäther der PolyhydiOxyphenole, which by reacting a poly-; hydroxyphenol with a considerable excess of, for example, 4 to 8 mol excess, of a halogen-containing epoxide in an ent alkaline medium. Polyhydroxy ^phenols; which can be used for this purpose are, inter alia, bisphenol, resorcinol, catechol, hydroquinone, methylresoroin, or mononuclear phenols such as 2.2-bis (4-hyiroxyphenyl) butane, 4.4 ^I- dihydroxybenzophenone, bis (4-hydroxyphenyl) ethane and 1,5-dihydroxynaphthalene. The halogen-containing epoxides can also be used, for example, by 3-chloro-1,2-epoxybutane, 3-bromo-1,3-epoxyh.exane, 3-chloro-l. 2-epoxyoctane un ^ J ^: .. represent.

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DIPL-INO- DIETER JANOER Wt-INQ. MANFRED SONING fAT E N TA NWA Π Ε

Examples of polymeric polyepoxides include the polyepoxypolyhydroxypolyethers, by reacting, preferably in an alkaline or acidic medium, a polyhydroxy alcohol or Polyhydroxyphenola Bit a polyepoxide obtained like the reaction product of glycerol and bis (2,3-epoxypropyl) ether, the reaction product of sorbitol and bist2,3-epoxy-2-methylpropyleather, the reaction product of pentaarythritol and 1,2-epoxy ~ 4,5-epoxypentane, the reaction product of bisphenol and bis (2,3-epoxy-2-ethylpropyl) ether, the reaction product of resorcinol and bie (2,3-epoxy-propyl) ether and the rede tion product of catechol and bis (2,3-epoxypropyl) ether.

Another group of polymeric polyepoxides includes the hydroxy-substituted polyepoxide polyethers, which are formed by reacting, preferably in an alkaline medium, a slight excess, e.g. 0.5 to 3 molar excess, of a halogen-containing epoxide, as described above, with any of the above-described polyhydroxyphenols, such as resorcinol, catechol, bisphenol, liis (2.2 ^l -dihydroxydinaphthyl) Bethan and the like. Have been obtained.

This group also includes the polyepoxy polyethers, which are produced by reacting, preferably in the presence of an acidic Compound, such as hydrofluoric acid, one of the halogen-containing epoxides described above with a polyhydroxy alcohol, such as glycerine, propylene glycol, ethylene glycol, Trimethylene glycol, butylene glycol and the like. Have been obtained and subsequently the product thus obtained with a alkaline component is treated.

Other polymeric polyepoxide compounds include Polymers and copolymers of the epoxy-containing monomers which have at least one polymerizable ethylene bond. If this type of monomer practically in the absence of alkaline or acidic catalysts, as when using Oxygen, heat, peroxy compound, actinic light and Like. Is polymerized, the same undergoes an addition Ροΐ, νuierization at the multiple bond so that the epoxy group U.N. ylutlußt b.isibt. These monomers can with themselves or with other monomers that have a double bond

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DIPL-INC. DIETER MNDER DR.-1NCJ. MANFRED BONINQ A f- Q Γ rj ι Q

_n PATINTANWAlTf O3O / t 5

are saturated, never styrene, vinyl acetate, methacrylonitrile, acrylonitrile, Vinyl chloride, vinylidene chloride, methyl acrylate, methyl methacrylate, Diallyl phthalate, vinyl allyl phthalate, divinyl adipate, Ohloroallyl acetate and vinyl methallyl pimelate polymerized "earth. Examples of these polymers include poly (allyl} 2,3-epoxypropyl ether), Poly (2.3-epoxypropyl crotonate), ally1-2.3-epoxypropyl ether-styrene copolymer, poly (vinyl-2.3-epoxypropyl ether), Allylglyoldyl ether vinyl acetate copolymer and poly (4-glycidyloxystyrene).

Examples of non-terminal polyepoxides include epoxidized esters of monocarboxylic acids unsaturated by several double bonds, such as epoxyated linseed oil, Soybean oil, perilla oil, oitioa oil, tung oil, walnut oil and hydrated tea Castor oil, methyl linoleate, butyl linoleate, ethyl 9.12 octadecadienoate, Butyl-9.12.15-octadeoatrienoiate, butyl eleostearate, mnoglycerides of the tung oil fatty acids, monoglycerides of soybean oil, sunflower oil, rapeseed oil, hemp seed oil, sardines, tree nut oil and the like.

Another group of terminal polyepoxides includes the epoxidized esters of unsaturated monohydroxy alcohols and polycarboxylic acids, such as d (2.3-epoxybutyl) adipate, di (2.3-epoxybutyl) oxalate, di (2.3-epoxyheptyl) succinate, di (2.3- Epoxybutyl) ealeate _f di (2.3-Epoxyoctyl) pjnßiiat, di (2.3-Bpoiypropy-Dphthalat, di (2.3-Spoxycyclohexyl) adipat, di (2.3-Epoxypentyl) thiodipropionat, di (5.6-Epoxytetradecyl) diphenyldio-Epoxy, di (3.4-Epoxytetradecyl) diphenyldioarboxylat, di (3.4-Epoxypentyl) tri (2,3-epoxypropy ^.) 1,2,4-butane tricarboxylate, di (5,6-epoxypentadecyl) tartarate, di (4,5-bpoxytetradecyl) maleate, di (3,4-epoxybutyl (citrate, and di (4,5-epoxyoctadeoyl) «& alon8t. Preferred members This group includes the glycidyl esters, such as the glycidyl esters of dicarboxylic acids, which preferably contain 2 to 18 carbon atoms, such as diglycidyl phthalate, diglycidyl leate, diglycidyl adipate, digylcidyl sebacate, digylcidyloyolohexanedicarboxylate and the like.

Another group of polyepoxides includes the epoxidized Esters of unsaturated alcohols and unsaturated carbonic acids, like 2.3-3poxybutyl-3.4-epoxypentanoate, 3.4-epoxy

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DIPl-INQ. DIETERJANDER DR-INCJ. MANFRED BDNINQ Λ PATENT LAWYERS

iiexyl-3.4-epoxypentanoate, 3.4-epoxycyclohexyl-3.4-epoxycyclohexanonate, 3.4-EpOXyCyCIoIIeXyIH. 5-epoxy octanoate, 2,3-epoxycyclohexylmethylepoxycyclohexane carboxylate.

Another group of epoxy-containing products includes epoxidized derivatives of polycarboxylic acids unsaturated by several double bonds, such as dimethyl 8.9.12.13-diepoxyeiconsandioate, dibutyl-7.8.11.12-diepoxyoctadecanedioate, dioctyl-10.ll.-diath.yl-8. 12/9/13-diepoxyeiconaanedioate, dihexyl-ö.T.lO.ll-diepoxyhexadecanedioate, didecyl-9-epoxyethyl-10.ll-epoxyoctadecanedioate, dibutyl-3-butyl-3 · 4. 5- o-diepoxycyclohexane-l ^ -dicarboxylate, dicyclohexyl-3.4.5.6-diepoxycyclohexane-1.2.-dicarboxylate, dibenzyl-1.2.4.5-diepoxycyclohexane-1.2-dicarboxylate and diethyl 5.6.10.11-diepoxyoctadecyl succinate.

Another group includes the epoxidized polyesters, which are produced by reacting an unsaturated polyhydroxy alcohol and / or unsaturated polycarboxylic acid or anhydride groups such as the polyester obtained by reacting 8.9.12.13-mcosadiene dionic acid with ethylene glycol is the polyester obtained by reacting diethylene glycol with 2-cyclohexene-1,4-dicarboxylic acid and the like, as well as mixtures thereof.

Another group includes the epoxidized hydrocarbons unsaturated by several double bonds, such as epoxidized 2,2-bis (2-cyclohexenyl) propane, epoxidized vinylcyclohexane and epoxidized dimer of cyclopentadiene.

Another group includes the epoxidized polymers and copolymers of diolefins, such as butadiene. examples for these include bitediene-acrylonitrile copolymers (Hycar rubber), butadiene-styrene copolymers and the like.

Particularly preferred, epoxy-containing organic products, which can be used in the method according to the invention, are the members of the group consisting of the organic compounds having a plurality of epoxyalkoxy radicals, E.g. two to four of these, which are linked to an organic radical which has one or two aromatic rings,

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DIPL-INQ. DIETER JANDER DlLl NC MANFRED BDNINO PATENT LAWYERS

organic «compounds which have a plurality of epoxyhydroxyalkoxy radicals, for example two to four, which are linked to an organic component which has one or two aromatic bings, the polyepoxy-containing polymeric reaction product of an aromatic polyhydroxyphenol and epihalohydrin, the polyepoxy-containing polymeric reaction product of an aliphatic polyhydroxy alcohol and epichlorohydrins, j the polyepoxy-containing polymeric reaction product of a polyhydroxyphenol and a polyepoxide compound, the polyepoxy-containing polymeric reaction product of an aliphatic i polyhydroxy alcohol and a polyepoxide compound, the poly j

Raerisate from epoxy-containing monomers, which contain at least one ■ polymerizable ethylene bond and have been prepared in the absence of alkaline or acidic catalysts, and copolymers of the above epoxy-containing monomers and a monomer which has at least one GH ₈ = G = group and in the absence of alkaline or acidic catalysts has been produced. The term "epoxyalkoxy" refers to an alkoxy that is substituted with an epoxy group. The term "epoxyhydroxyalkoxy" refers to an alkoxy that is substituted with a hydroxyl and epoxy group.

Of particular importance, especially in view of the good quality of the resinous from these products hergestell te About trains the monomeric and polymeric Glyeidylpoly ether of Dihydro'xyphenole, as are obtained by reacting Epiohlorhydrin and a dihydric phenol in an alkaline medium are. The monomeric products of this type can be expressed by the general formula

A Λ

OH ₂ -CH-Gh ₂ -OHO-GH ₈ -GH-GH ₈

reproduce, in which R is a divalent hydrocarbon radical äeo is dihydroxyphenol. The polymeric products will generally not be a simple single molecule, but rather will be rather a complex mixture of glycidyl polyethers of the general formula

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DIFL-INQ; BIDDERS JANDER WL-INQ. MANFRED SONINQ FATE N LAWYERS

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OH ₁ -OH-CHa-O (HO-CHg-OHOH-OHg-O) _n RO-CH ₄ -CiI - CH.

in which R is a divalent hydrocarbon radical of a deihydroxyphenol and η is an integer in the series 0,1,2,3 etc. is. If for any single molecule of the polyethylene η is an integer, the fact that the polyether obtained is a mixture of τοη compounds means that the certain value for η is an average value that need not necessarily be zero or an integer. The polyethers may in some cases contain a very small amount of products with one or both terminal oleicidyl residues are in hydrogenated form.

The preferred glyoidyl polyethers of the dihydroxyphenols described above can be prepared by reacting the required proportions of a dihydroxyphenol and epichlorohydrin in an alkaline medium. The desired alkalinity is obtained by adding basic substances such as HatriUB or potassium hydroxide, preferably in a stoichiometric excess to epichlorohydrin. The reaction is preferably carried out at a temperature of 50 to 15O ⁰ O. Heating is continued for several hours to bring the reaction to completion and the product is then washed free of salt and base.

The members of the group of polyepoxides described are the glycidyl polyethers of dihydroxyphenols, and in particular 2,2-bisU-hydroxyphenyl) propane, which has an epoxy equivalent of 1.0 to 2.0 and a molecular weight of 900 to 2900, particularly preferably those compounds which have a softening point of at least about 100 ⁰ C after the Durrans mercury method.

Another group of polyglycidyl ethers which can be used according to the invention are the polyglycidyl ethers of α, α-ω -Q-tetrakis (hydroxyaryl) alkanes. This group of compounds is described in US Pat . No. 2,806,016. The polyglydidyl ether produced according to example 1 of this patent csclirift has a melting point of 85 ⁰ C and contains 0.452 epoxy equivalent per IUO g,

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DIPL-INC- DIETER JANDER DR.-1 NC /. MANFRED BDNINC A CQC 7 / ι Q

• PATENT LAWYERS. I O ü ö / H O

- 11 The invention is explained in the following for example:

example 1

Two moles (142 g) of acrylamide are dissolved in methanol. With stirring ± tn is added slowly to the Rüokflußtemperatur of methanol 1 mole (142 g) 1.4 Cyclohexylbismethylarain in methanol. After the addition is complete, the reactants are refluxed for 1 hour. Stripping off the methanol and drying the product obtained leads to a diadduct which has the following analytical values: Amine number 381 (theoretical value 395) » 1 · N 18.2 (theoretical value H 19.7). This water-soluble product is a white semi-wet substance.

Example 2

Ee 2 moles (142 g) of acrylamide are dissolved in M ethanol and brought to reflux temperature. Do this slowly 1 mol (129 g) of aminoethylpiperazine, also dissolved in methanol, was added. After the addition is complete, the reactants will stirred and refluxed for an additional 60 minutes. Then we let methanol stripped off under vacuum and collected the product. The same thing . ?! is a white solid with the following analytical values: Amine number 609 (theoretical Amine number 621), £ N 24.5 (theoretical £ 25.8).

Example 3

JCs be 236.1 g of an epoxy resin obtained from bisphenol A and epichlorohydrin and having a Epixyäquivalentgewicht of 525, melted at 12O ⁰ C. There are 63 "9 g of Härtungs'mittels according to Example 1 at 120 ⁰ C erechmolzen, and then the molten epoxy product with rapid stirring added. Immediately after reaching a homogeneous product, the same is poured out and cooled. This product gelled after it iet been pulverized into a fine powder in 15 seconds at 150 ⁰ C and immediately performing means is detected by -Dehnbarkeitstests at 205 ⁰ C. The curing of the product. The product is completely hardened after 1 minute at 232 ° C., so that this is a rapid hardening system.

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DIPL-INCDIETERJANDER DR.-INQ. MANFRED »ONING Ί K Q E * 7 A Q PATENT attorneys' ΌΟΟ / HO

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Example 4

The curing agent according to Example 2 is mixed with an epoxy resin obtained from bisphenol A and epichlorohydrin, which epoxy resin has an epoxy equivalent weight of 925. Mixing is carried out in three different proportions, namely 32.3 g of hardener to 267.7 g of epoxy resin, 38.3 g of hardener to 261.7 g of epoxy resin and 44.3 g of hardener to 255ti g of epoxy resin. These blends are referred to as # 1, # 2, and # 3. Nr. 1 gelled in 60 seconds at 15O ⁰ C and 30 seconds at 205 ⁰ C, no. 2 gelled in 75 seconds at 15O ⁰ C and 35 seconds at 205 ⁰ C, no. 3 gelled in 45 seconds at 15O ⁰ C and 25 seconds at 205 ^° C. There is no formation of bubbles in the film, as can be caused by reversing the reaction and releasing volatile by-products. The Härtungezeit this product is 3 minutes at 232 ⁰ C, and then the same is the extensibility.

Example 5

A coating powder that is suitable for insulating the stators of electric motors is described below Way compiled:

Epoxy resin (according to Example 2) 4460 G

N.N'-bisO-propioamide jaminoethylpiperazine 790 g powdered mica 1580 g

amorphous silica 211 g

The powdered mica is used for heat resistance and the an.orphic silica serves as a flow control agent. The epoxy resin is melted in a dispersion blade mixer A Baker-Perkine and kept at 120 ⁰ C. The hardener is then added and mixed for 1.5 minutes. The entire mass is poured over dry ice for rapid cooling. This product is then pulverized to form a solid, powdered coating which is suitable for fluidized bed applications and other methods of application. A square sample with dimensions of 11 × 11 × 10 cm is coated with the mass and the mass is cured at 232 ° C. for 2 to 3 minutes. The percentage of coating on the edge compared to that on the flat surface is $ 68. The coated sample has a cut through temperature at the edge of greater than 238 ° C. ,

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DIfL-INO. DIETER JANDER DR..INQ. MANFRED BONINO 1595749 PATENT LAWYERS

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Example 6

The coating powder after. Example 5 is used to coat a 12.7 cm electric motor stator in an industrial spray coater applied. This device applies a molten film thickness of 0.28-0.47 ma to the stator preferential mass on. The Uebefzug amounts to at the corners a thickness of 0.1-0.18 mm. The average edge coverage on the stators with this powder amounts to about $ 45. The best edge coverage is given with a value of achieved on a single stator.

An investigation into the variability of the coating thickness on the stators is carried out with these stators coated by means of the device. There will be 10 pieces measured, which are cut out of 5 stators, namely with regard to the change in the Ueberzugsdioke on the flat Places, which amounts to about 3, the change in the coating thickness at the corners amounts to less than 1 and the change in percent edge coverage is about 50. These changes compare very favorably with the changes expressed in percent with respect to the edge coverage, as it is by means of two commercially available Coating powder is achieved, which are applied by means of the same coating device. In any case amounts to see the change on over $ loo $ for these off-the-shelf Products.

Example 7

A stator coating powder is made up using the following amounts of the following ingredients: Epoxy resin (according to Example Z) 4800 g

N »li ^l -bia (3-Propioaraid) aminoethylpiperazine 822 g

Silicone resin 56 g

powdered mica 1690 g

amorphous silica 281 g

TiO ₂ pigment 411 g

The silicone resin serves as an anti-cratering agent. The procedure used to assemble this stator eye powder is similar to that of Example 6.

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DIPL-INC DIETER JANDER DItI NQ. MANFRED BONINq PATENT LAWYERS

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This powder gelled at 150 ⁰ C in 3 minutes and at 2o5 ° G in 1 minute. If coating is carried out on a steel profile by means of the fluidized bed process, the coating is smooth and shiny with only slight wave formation on its surface. This results in a # 62 strength edge cover on a square sample, and a cut-through temperature of higher than 238 ⁰ C. The curing time at 232 ⁰ C amounts to 3-4 minutes. There are coated with this powder various steel samples and cured for 3.0 minutes at 232 ⁰ G. These samples are then immersed in the following solvents and chemicals:

Water 10 # citric acid

Aviation gasoline White spirit

20 # hydrochloric acid methyl isobutyl ketone

$ 50 sulfuric acid acetone

$ 20 nitric acid. $ 5 acetic acid

$ 30 Sodium Hydroxide Methanol

Isopropanol ethanol

Oleic Acid Chlorofor »

$ 20 lactic acid toluene

After 24 hours of immersion at 25 ^° G, only two solvents have affected the films. These are acetone, which softens the film, and chloroform, which softens and dissolves the film. All other solvents and chemicals have no noticeable effect. The immersion is continued for 7 days and then a re-examination is carried out. No further deterioration in the coatings on the samples is observed with any of the solvents or chemicals.

Example 8

Weigh 2 moles (142.2 g) of aaylamide and 500 g of absolute methanol into a reaction flask. The acrylamide is brought into solution by stirring. At 5O ⁰ C, the Aerylamidlösung is stirred and 1.0 mole (L64> 0 g) 1.4-bis-Aminoäthylbenzol slowly added in 164 g of absolute methanol. The exothermic heat of the reaction keeps the reactants at 55 ° C. After refluxing (67 ° C.) for 1 hour, the methanol is stripped off in vacuo and the white crystalline solid is dried.

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DIPL-INQ. DIETER JANDER WLINQ. MANFRED BONINQ PATENT LAWYERS

Analysis values of the liadduct Amine number 366.6 (theory 367)

% Nitrogen 17.4 (theory 16.3)

It «ground 67.8 g of the above acrylamide adduct at 110 ⁰ C with 232.2 g of epoxy resin according to Example 3 were mixed and stirred for 30 seconds at this temperature. The mixture is then allowed to cool and pulverize. The powdered product melts well when heated. The same has a flux of 11.6 cm at a 6o ° inclination at 15O ⁰ C and gelled in 2 minutes at this temperature. At. 205 ⁰ C the same gels in 30 seconds. Films are bubble free upon curing. The Härtungezeit is 9 minutes at 15O ⁰ or G 1 minute at 232 ° C. Films produced from this mass are ^{cured at 150 °} C. and appear satisfactory and pass about 2/3 Olson-Button elongation tests to which they are subjected. This is equivalent to $ 26 film stretch.

Example 9

The diaorylamide adduct of piperazine is obtained by means of hold at the reflux of 2 moles (142 g) of acrylamide in methanol 1 mole (86 g) of piperazine 1 SLande made. After this Withdrawal from the vacuum, the white solid shows the following analytical values:

Aainsahl 486 (Theorte 475)

M 24.5 (theory 27.1)

FP 23U ° C.

Ea be 0.234 mol (244.8 g j dee Epoxyharaes to 0.234 mol (55.2 g) of added Diaorylamidadduktes of piperazines according to Example 3 at 150 * C. The temperature is raised to 18O ⁰ C and after 5 minutigem holding this temperature is bM the curing agent is dissolved in the epoxy resin and the mixture is then quickly quenched.

After grinding to a fine particle size, the powder is examined for its hardening time. At 150 ⁰ C, curing takes place in 7.0 to 7.5 minutes and at 2o5 ° C in 3.5 -4.0 minutes. A 3 g KUgelohen having a diameter of 28.6 18.7 cm bb flows along a 60 ° inclination in the form of a hot plate maintained at 150 ⁰ C. The films are hard and shiny after hardening and lead to a good one

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DIPPING DIETER JANDER DIt-INQ. MANFRED BüNINp PATENT LAWYERS

159P749

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Clinging to steel. This product is useful as an epoxy film where hardness and adhesion are more important than film flexibility are.

Example 10

There are 0.14 equivalents (21.3 g) of the diacrylamide adduct of 1,4-bisaminoethylbenzene and 0.14 equivalents (16.5 g). Diaorylamide adduct of piperazine at 150 ° 0 and 0.28 equivalents (260 g) of the epoxy resin according to Example 4 are mixed for 1 minute. The product is a clear, transparent solid which can be easily pulverized in standard equipment. The powder flows 7.76 cm on a 60 ° angle at 150 ⁹ C and gelled in 4.5 minutes bä. this temperature. At 205 ^° C., gelling takes place in 1.5 minutes. The hardening time at 150 ^° C. amounts to 90 minutes and at 232 ^° C. to 6 minutes. In baking at 150 ⁰ C, the product 'Olson the * button test consists only with slight cracking. The film is hard, free from pook marks, pid free from bubbles. The mixture thus cures relatively slowly and is easy to handle as a powdered coating resin.

009808/1613

Claims (2)

DIPL-INQ. DIETER JANDER DR.-INQ. MANFRED BONINQ PATENTANWÄLTE I 595/49 3 (DAHLEM) H0TTENW% 3 15 13 03 Telegram ·: Consideration Berlin May 27, 1966 793/12229 DE patent application for GMERAL MILLS, INC. Minneapolis, Minnesota 55440 U.S.A. patent claims 1. Use of a diacrylamide adduct of a polyamine as a curing agent for epoxy resins, the polyamine is selected from the group consisting of cyclic aliphatic and aromatic amines and at least one has primary amine group and at least three exchangeable hydrogen atoms. 2. Use of the diacrylamide adduct of 1,4-cyclohexyl-bismethylamine and / or 1,4-cyclohexyl-bis-ethylamine and / or 1,4-benzene-bis-methylamine and / or 1,4-benzene-bis-ethylamine and / or amine ethylpiperazine and / or piperazine. 009808/1613 Poitsclnckkonto Berlin-West 174384 Berliner Bank AG., Deposit kaise 1