CS196156B1 - Epoxy compositions - Google Patents

Description

The invention relates to epoxy compositions which contain solid bis / N-cyclohexyl-3-aminopropyl) amine as the hardener of the epoxy binder.

A very important part of compositions influencing processing technology, curing.

the final properties of the cured compositions are hardeners. A number of different materials that can be used to cure epoxy resin compositions are currently known and described in the literature / Hoppe M .: Paint Manufacture, October 1975, p. 9; C.A.May, J.Tanaka: Epoxy resins, chemistry and technology, M.Dekker, N. York 1973, p. 239]. The most extensive group of commonly used hardeners are amines and polyamines, which are well suited for many epoxy resin applications. However, they are not suitable for some special applications, particularly for the production of powdered epoxy compositions, since they often have too high reactivity, are liquid, poorly dosed and do not give the desired mechanical properties of the cured compositions.

Compositions of the present invention which contain epoxy resins, a hardener, and optionally additives and / or modifiers selected from the group consisting of accelerators, retarders, flow agents, extenders, flame retardants, pigments, dyes, fillers and macromolecules of the compound do not have these drawbacks. SUMMARY OF THE INVENTION These compositions comprise as hardener 2 to 95 g, based on 100 g of epoxy resin, bis / N-cyclohexyl-3-aminopropyl] amine tetrahydrate, or up to 90 g, based on 100 g of epoxy resin, and mixtures thereof in mass ratio of 1:99 to 99: 1 with functional compounds selected from the group consisting of aliphatic, cycloaliphatic, heterocyclic or aromatic amines, polyamines and aminoamines, dicyandiamide and its derivatives, in particular biguanides, polycarboxylic anhydrides and compounds with at least two carboxyl groups in the molecule, and / or with complex boron trifluoride compounds.

The bis (N-cyclohexyl-3'-aminopropyl) amine tetrahydrate is prepared from the actual bis (N-cyclohexyl-3-aminopropyl) amine and water either in organic solvents or in a melt. It is a crystalline substance having a melting point of 45-46 ° C. Distillation residues resulting from the hydrogenation of beta-cyanoethylcyclohexylamine having a boiling point greater than 130 ° C at about 4000 Pa can also be used for its preparation.

Low molecular weight high molecular weight epoxy compounds are suitable for the preparation of the epoxy compositions of this invention. They are mainly polyepoxide compounds obtained by the alkaline condensation of epihalohydrins (epichlorohydrin) and their derivatives or dihalohydrins (dichlorohydrin) with substances whose functional groups contain at least two active hydrogen atoms. They also include epoxy compounds obtained by epoxidation of unsaturated compounds and polymers or copolymers containing epoxy groups.

The first group includes, in particular, polyglycidyl ethers derived from polyhydric phenols, such as 4,4-dihydroxydiphenyl-propane (bisphenol A), 4,4-dihydroxydiphenylsulfone (bisphenol S), tris- and tetrakis (hydroxy-191515 phenylalkanes), resorcinol, hydroquinone and phenolformaldehyde and cresoformaldehyde novolaks, and polyglycidyl ethers derived from vi-ill alcohols, in particular alkylene glycols and polyalkylene glycols. The technically most important are epoxy resins based on 4,4-dihydroxydiphenylpropane. This group also includes polyglycidyl esters of aliphatic, cycloaliphatic and aromatic polycarboxylic acids such as adipic acid, sebacic acid, azelaic acid, diraerized unsaturated fatty acid, phthalic acid, phthalic acid tehydroxy, hexahydrophthal, trimellitic, cyanuric and isocyanuric, polyglycidylthioethers and polyglycidic lamina.

The second group of polyepoxide compounds includes aliphatic and cycloaliphatic polyepoxide compounds. Suitable aliphatic epoxides are epoxidized polymers and copolymers of linear conjugated parts, epoxidized oils, unsaturated esters and unsaturated aliphatic hydrocarbons (budadiene dioxide, divinylbenzene dioxide). Cycloaliphatic epoxides include compounds containing rings of cyclopentene oxide β bis (2,3-epoxycyclopentyl) ether, 2,3-epoxycyclopentanolglycidylether, cyclohexene oxide / 3,4-epoxy-6-methylcyclohexyl-3,4-epoxy-6-methylcyclohexanecarboxylate, vinylcyclohexene dioxide; , 1-dimethylolcyclohexenoxide bis-glycidyl ether (cyclooctenoxide, bicycloheptenoxide and tricyclodecenoxy) (dicyclopentadiene dioxide, epoxydicyclopentylglycidyl ether). Further, epoxidized hydroaromatic acetals and ketals, epoxidized polycyclopentadiene, epoxidized polyesters and other high molecular weight materials can be mentioned.

The third group of polyepoxide compounds include polymers and copolymers of unsaturated epoxy compounds such as glycidyl acrylate, glycidyl methacrylate and allyl glycidyl ether.

The polyepoxide compounds are used singly or in admixture with each other. Their combination achieves the desired properties of the curing films, eg increasing hardness or plasticity. Variations in the properties of the polyepoxide compounds are also achieved by modifications thereof, for example by esterification with monomeric or polymeric fatty acids, or by the addition of mono-epoxide compounds and unsaturated polymerizable monomers.

All curing agents used in the curing of epoxy resins such as ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenediamine, N-aminoethylpiperazine, aminoxylylenediamine, propylcyclohexylamine,

4,4 ' -diaminodicyclohexylmethane, 4,4 ' -diaminophenylmethane, roetaphenylenediamine, 4,4 ' -diaminodiphenylsulfone, isophorone diamine, piperidine, aminopyridine, trimethylhexamethylenediamine, fatty acid amino amides, tris / dimethylaminomethyl / phenol, dicycloamide; substituted biguanides, monomethyl dicyandiamide, 1-phenyldicyanediamide, substituted ureas, acid esters of aliphatic and aromatic polyacids, aromatic and aliphatic anhydrides of organic acids, as well as complex boron trifluoride compounds.

As reaction accelerators, for example, aliphatic polyalcohols / glycerin, glycol, trimethylpropane, pentaerythritol, etc., phenols, cresols, xylenols, salicylic acid and substituted derivatives thereof, such as tris / dimethylaminomethyl / phenol and the like, tertiary amines such as e.g. triethanolamine, quaternary ammonium salts such as trimethylbenzylammonium chloride and bases derived therefrom,

BF3 complexes and Lewis acids, thioglycolic acid and its esters, alkali hydroxides, metal salts of fatty acids, metal chelates of salicylic acid, hexamethylenetetramine, aminoalkylglycol monoborate, monoaminopyridine and the like.

As retarders, substances containing, for example, at least one aldehyde or ketone group in the molecule / acetophenone, benzophenone, fural, furalacetone condensates, ketone resins and the like can be used. /.

The fillers, pigments, flame retardants, solvents, plasticizers and various other additives used in the preparation of the compositions are chosen according to the methods of their application. These include adhesives, sealants, paints, powders, varnishes and potting compounds, etc.

Said hardener is particularly advantageous from a technological point of view in the formulation of masses processed on continuous kneaders, where solids need to be dosed; furthermore, the hardener is still in air, moisture and carbon dioxide are not as sensitive to accurate dosing, and the water present acts as an accelerator and flow regulator of the composition in applications. It can be used in the preparation of powder coatings, adhesives, molding materials, but also laminates, liquid paints, etc.

Example 1

100 wt. parts of epoxy resin based on the condensation products of Bisphenol A and epichlorohydride with an epoxy equivalent of 0.096 / 100 g and a softening point of 96 ° C are mixed with 12.5 wt. parts by weight of bis (N-cyclohexyl-3-aminopropyl) amine tetrahydrate, 50 wt. parts of titanium white, 3 wt. parts of a solid polyacrylate-based flowable agent, and the bulk material obtained is homogenized in a continuous kneader at 80 ° C. After cooling, the mass is crushed and ground in a hammer-mill to a particle size below 100 _</ UWM and used as the powder coating composition for application in an electrostatic field. After application and curing 10 min. at 160 to 180 ° C the material has a good film appearance, excellent mechanical properties (9 mm digging, 500 mm impact) and excellent chemical resistance to alkalis, acids and common solvents.

Example 2

100 wt. parts of the epoxy resin of Example 1 were similarly mixed and homogenized with 14 wt. parts by weight of bis (N-cyclohexyl-3-aminopropyl) amino tetrahydrate, 50 wt. parts feldspar, 20 wt. parts of hive S1O2, 3 wt. parts by weight of chromium trioxide, 2 parts by weight, parts by weight of a solid disintegrating agent based on polyacrylates adsorbed onto silica and ground to a particle size of 40 to 200 .mu.m. The powder coating obtained is used for fluidized-bed sputtering on electric motor rotors. It has a drainage at 190 ° C around 10 mm, excellent edge coverage (60%) and excellent electrical properties up to 120 ° C.

Example 3 wt. parts of epoxy resin according to Example 1 and 20 wt. After grinding, 4 parts by weight of epoxy resin having an epoxy equivalent of 0.26 / 100 g and a softening temperature of 81 [deg.] C. are mixed with a 4 wt. parts by weight of dicyandiamide, 4.5 parts by weight, parts by weight of bis / N-cyclohexyl-3-aminopropanol / amine tetrahydrate, 5 parts by weight; parts of iron oxide, 4 wt. parts of feldspar, 10 wt. parts Sd.02 “drift, 5 wt. parts by weight of zinc phosphate and 2 wt. parts of polybutyl acrylate adsorbed onto siloxide. The mixture is homogenized in a continuous kneader at 80 to 100 ° C, and after cooling it is ground to a fluidized powder coating composition which is used to coat steel tubes at 200 ° C. The resulting film has excellent mechanical and anticorrosive properties.

Example 4

100 wt. at 20 ° C, 50 parts by weight of epoxy resin based on cresol novolak condensate with epichlorohydrin having an epoxy equivalent of 0.51 and a viscosity of 100,000 mPa. parts by weight of bis (N-cyclohexyl-3-aminopropyl) amine tetrahydrate, 10 wt.

parts of colloidal S1O2, 2 wt. parts of polyvinyl butyral. The thixotropic mass obtained is used as an adhesive having a workability of min. 20 h at 20 ° C in an amount of 1 kg. After curing of 1 h / 120 ° C, it has excellent shear strength and especially peeling at normal temperature.

Example 5

100 wt. parts of the epoxy resin shown in Example 4 are dissolved in 100 wt.

Claims (1)

SUBJECT Epoxy compositions based on epoxy resins, hardeners, and optionally additives and / or modifiers selected from the group consisting of accelerators, retarders, flow agents, extenders, flame retardants, pigments, dyes, fillers and macromolecules of the compound, characterized in that they contain as hardener 2 to 95 g, based on 100 g of epoxy resin, bis (N-cyclohexyl-3-aminopropylpyridine) amine tetrahydrate or 2 to 90 g, based on 100 g of acetone epoxy parts, are added 30 wt. parts by weight of bis (N-cyclohexyl-3-aminopropyl) amine tetrahydrate and 20 wt. parts of an acid ester based on an adduct of hexahydrophthalanohydride with pentaerythritus having an acid number of 335 mg KOH / g. The resulting solution is impregnated with a glass cloth which after curing of the solvents is precured for 10 min at 80 ° C. 12 sheets of impregnated fabric are pressed at 2.0 MPa at 60 ° C for 1 h. The resulting laminate has an excellent surface, very good mechanical properties at both normal and reduced temperatures. Example6 100 wt. 70 parts by weight of epoxy resin based on cresol novolak having a softening point of 74 ° C and an epoxy equivalent of 0.45 / 100 g are premixed. parts of ground slate, 15 wt. parts by weight of zinc stearate, 50 wt. parts by weight of bis (N-cyclohexyl-3-aminopropyl) amine tetrahydrate and 15 wt. parts of β, β-diphenylpropanedibuanide in a bulk mixer and then homogenized on a calender at 70 ° C. The grinding mass on the hammer mill is suitable for use as a compression mixture which can be processed at 180 ° C at a pressure of 7.0 MPa and for 5 minutes. The heat resistance of the cured mass is about 155 and the bending strength is 0.7 to 0.9 J / cnt ² . BACKGROUND OF THE INVENTION Resins, mixtures thereof in wt. ratio. 1:99 to 99: 1 with functional compounds from the group consisting of: aliphatic, cycloaliphatic, heterocyclic or aromatic amines, polyamines and aminoamides, dicyandiamide and derivatives thereof, in particular biguanides, polycarboxylic anhydrides and compounds having at least two carboxyl groups per molecule, and / or complex boron trifluoride compounds.