DE19729875A1 - Hardeners for epoxy] resins - Google Patents

Abstract

Hardeners (I) for epoxy resins, containing a mercapto compound (A) of formula X(CH2C(OH)HCH2SH)n (I). In (I), n = 5 or more; X = a residue obtained by removing n hydrogen atoms from a compound (a) with n or more active H atoms. Also claimed are: (i) epoxy resin compositions (II) containing hardener (I) and a polyepoxide compound (B); (ii) a process for the production of hardened epoxy resin by reacting (B) with (I); and (iii) hardened epoxy resin containing a product of the above reaction (ii). Preferably Compound (A) has the formula (Qs)Z<1>(Z<2>(Q))rZ<1>(Q)s (II), in which Q = -CH2-CHOH-CH2-SH; -Z<1>-(Z<2>)r-Z<1>- = X = the residue of a compound with a chain structure; Z<1>, Z<2> = organic groups; s = 1 or 2; r = a number given by the equation n = r + 2s. Compounds (a) comprise (a1) saccharides, (a2) sugar alcohols, (a3) compounds in which some or all of the hydroxyl groups in (a1) or (a2) have undergone addition with not more than 10 mono-epoxide compounds (b) per OH group, (a4) polyalkylene- polyamines with 5-8 active hydrogens, and/or (a5) compounds in which some or all of the active H atoms in (a4) have undergone addition with not more than 10 mono-epoxides (b) per active H atom. Preferred (A) has a mercaptan equiv. of 100-1000.

Description

The present invention relates to curing agents for Epoxy resins Epoxy resin compositions, hardened epoxy resins and a process for the preparation of hardened ep oxide resins. In particular, the present invention relates Epoxy resin curing agent, which epoxy resins quickly harden at room temperature and at low temperatures, whereby the resulting hardened epoxy resins are both good mechani strength and resistance to water and have different types of chemicals.

In construction (civil engineering) and other constructions areas, it is often necessary to be short or strict Comply with production times or the procedures in cool Climate. For this reason, it is desirable that epoxy resins used in these areas quickly Can be hardened at room temperature or at low temperatures harden the fittings. It is known that curing agents on Mercap can be used to quickly add epoxy resins Harden room temperature or at low temperatures. To  some examples of these mercapto-based curing agents counting:

• (1) Polymercaptocarboxylic acid ester polyhydric alcohol like trimethyrene propane (disclosed in Japanese Kokai 61-162517);
• (2) Polymercaptans obtained from di- or triglycidyl ethers of oxyalkylene ethers of trimethyrene propane (disclosed in Japanese Kokoku No. 47-48279); and
• (3) tetravalent-functional polymercaptans obtained from tetraglycidyl diamines (disclosed in U.S. Patent No. 4,879,414 and 4,927,902).

However, the curing agents according to (1) are disadvantageous lig that resistance to chemicals, in particular the alkali resistance of the resulting hardened product due to the ester groups in the molecules is. In addition, the hardening agents according to (2) and (3) disadvantageous that the mechanical strength of the resulting hardened resins and their resistance to water and different types of chemicals is insufficient. That's why is the use of mercapto-based curing agents still due to these inferior properties limited.

The present invention therefore provides curing agents tel for epoxy resins based on mercapto according to claim 1 Available which have improved fast-curing properties at room temperature and improved curing properties exhibit at low temperatures and also the mecha strength and chemical and chemical resistance Improve the water of the resulting hardened epoxy resins.

The curing agent for epoxy resins according to the invention contains a mercapto compound (A) according to the following formula (1):

in which "n" is an integer equal to or greater than 5 and "X" is a residue in which "n" are hydrogen atoms from a verb dung (a) ent with "n" or more active hydrogen atoms were removed.

In one embodiment of the present invention according to claim 2, the mercapto compound (A) corresponds to fol gender formula (2):

in which "Q" is a group of the following formula:

5FZ¹- (Z²) r-Z¹- represents a radical "X", the radical "X" is a residue of a compound having a chain structure; "Z¹" is an organic group; "s" a number of "Q" groups, which are bound to "Z¹" means and an integer is 1 or 2; "Z²" is an organic group; and "r" represents a number of "Z²-Q" groups and a whole Is a number that satisfies the relationship n = r + 2s.

According to a further embodiment of the present Invention according to claim 3, compound (a) is one of the Links:

• (a1) saccharides;
• (a2) sugar alcohols;
• (a3) Compounds in which some or all of the hydroxy groups of the saccharides (a1) or the sugar alcohols (a2) not more than 10 monoepoxide compounds (b) per hydroxy group are added;
• (a4) Polyalkylene polyamines with 5 to 8 active water atoms of matter;
• (a5) Compounds in which some or all are active Hydrogen atoms of the polyalkylene polyamines (a4) with not  more than 10 monoepoxide compounds (b) per active water atom are added.

In a further embodiment of the present Er invention according to claim 4, the mercapto compound (A) a mercaptan equivalent between 100 and 1000.

The present invention further provides a Epoxy resin composition according to claim 5, containing a curing agent for epoxy resins containing a mercapto compound (A) according to the following formula (1):

in which "n" is an integer equal to or greater than 5 and "X" is a residue in which "n" are hydrogen atoms from a verb dung (a) ent with "n" or more active hydrogen atoms were removed, and a polyepoxide compound (B).

In one embodiment of the present invention According to claim 6, the polyepoxide compound (B) is one of the Links:

• (B1) polyepoxide compounds manufactured by Addi tion of one of the polyphenols bisphenol A, halogenated bis phenol A, bisphenol B, bisphenol AD, bisphenol F, halogen bisphenol F, resorcinol, hydroquinone, pyrogallol, Catechol, 4,4'-dihydroxybiphenyl and / or 1,5-hydroxynapht halin with two or more equivalents of epichlorohydrin;
• (B2) one of the polyphenol epoxy resin compounds Phe nolnovolac, brominated novolac and / or cresolnovolac;
• (B3) polyglycidyl ester polyepoxide compounds;
• (B4) polyglycidylamine polyepoxide compounds;
• (B5) polyepoxide compounds manufactured by Addi tion of one of the polyhydric alcohols hydrogenated bisphenol A, ethylene glycol, propylene glycol, tetramethylene glycol, ethyl lenoxide adduct of bisphenol A, propylene oxide adduct of bis phenol A, 2,2-dimethyrene propane, trimethyrene propane, pentaery  thritol, dipentaerythritol and / or sorbitol with two or more equivalents of epichlorohydrin;
• (B6) alicyclic polyepoxy resin compounds; and or
• (B7) heterocyclic polyepoxide compounds.

According to a further embodiment of the present Invention according to claim 7 is the ratio of the mer Captan equivalents of the mercapto compound (A) to the epoxidä equivalent of the polyepoxide compound (B) 1/05 to 1/2.

In a further embodiment of the present Er invention according to claim 8 contains the epoxy resin composition zung also a basic substance (C), which is used as a hardening accelerator is used, and which is a Amine (C1), a compound (C2) with a protected amino group which is converted into a free amino group by hydrolysis can be performed, and / or a phosphine (C3).

In a further embodiment of the present Er invention according to claim 9 contains the epoxy resin composition a compound (D) with a phenolic Hydroxyl group as a curing accelerator.

In a further embodiment of the present Er The invention of claim 10 contains the epoxy resin together setting also compounds (E1) with one or more carb oxyl groups, Lewis acids (E2) and / or amine complex salts of Lewis acids (E3) as the pot life regulating agent (E).

Furthermore, the present invention provides a ver drive to manufacture a hardened epoxy resin according to Claim 11 available, which is the implementation of a poly epoxy compound (B) with a curing agent for epoxy resin containing a mercapto compound (A) according to the following Formula 1):

in the "n" an integer equal to or greater than 5 and "X"  Rest is where "n" are hydrogen atoms from a compound (a) removed with "n" or more active hydrogen atoms were included.

According to an embodiment of the present invention according to claim 12, the method also includes Reacting the mercapto compound (A) with the polyepoxide ver bond (B) in the presence of a basic substance (C) as Hardening accelerator, wherein the basic substance (C) a Amine (C1), a compound (C2) with a protected amino group which is converted into a free amino group by hydrolysis can be performed and / or is a phosphine (C3).

According to a further embodiment of the present Invention according to claim 13 further comprises the method reacting the mercapto compound (A) with the polyepoxide compound (B) in the presence of a compound (D) with a phenolic hydroxyl group as a curing accelerator.

According to a further embodiment of the present Invention according to claim 14 further includes the method reacting the mercapto compound (A) with the polyepoxide compound (B) in the presence of compounds (E1) with a or more carboxyl groups, Lewis acids (E2) and / or amine complex salts of Lewis acids (E3) as the pot life regulate agent (E).

The present invention further adjusts hardened epoxy resin according to claim 15 available ent holding a product from a curing reaction between a polyepoxide compound (B) and a curing agent for an epoxy resin containing a mercapto compound (A) according to following formula (1):

in which "n" is an integer equal to or greater than 5 and "X" is a residue in which "n" are hydrogen atoms from a verb dung (a) ent with "n" or more active hydrogen atoms  were removed.

The present invention relates to a curing agent for epoxy resins with a mercapto compound (A), an ep oxide resin composition with an epoxy curing agent and a polyepoxide compound (B), a process for curing an epoxy resin composition and a cured epoxy resin.

The mercapto compound (A) is represented by the following formula (1) shown:

in which "n" is an integer equal to or greater than 5 and "X" is a residue in which "n" are hydrogen atoms from a verb expression (a) (described below) with "n" or more active hydrogen atoms have been removed.

In formula (1), "n" is preferably 5 to 12. When "n" is less than 5, the mechanical strength is like that Tensile strength, compressive strength and flexural strength, and the Resistance to water and chemicals (like the against acid, alkali, solvent and oil) of the ge hardened epoxy resin insufficient.

The mercapto compound (A) can be obtained by well known ones Methods, for example by adding "n" or more Epichlorohydrins to compound (a) under alkaline Conditions, hydrogen chloride release and addition of Hydrogen sulfide to the resulting polyepoxide compound getting produced.

Examples of the compound (a) are as follows given in (al) to (a11); it is all about organic compounds with active hydrogen-containing Groups such as hydroxyl groups, amino groups and the like. a .:

• (a1) Saccharides: monosaccharides such as galactose, gluco se, fructose, heptose and octose; Disaccharides such as sucrose; and oligosaccharides with the above monosaccharides as  structural unity;
• (a2) Sugar alcohols such as arabitol, sorbitol, manitol and sedoheptitol;
• (a3) Compounds in which some or all of the hydroxy groups of the saccharides according to (al) or the sugar alcohols according to (a2) with no more than 10 monoepoxide compounds (b) (which will be described later) added per hydroxy group are;
• (a4) polyalkylene polyamines such as diethylenetriamine and Triethylene tetraamine;
• (a5) Compounds in which some or all of the acti ven hydrogen atoms of the polyalkylene polyamines according to (a4) no more than 10 monoepoxide compounds (b) (the later are described) added per active hydrogen atom are;
• (a6) vinyl (co) polymers containing vinyl monomers with a hydroxy group as a structural unit such as polyvinyl alcohol or hydroxyethyl (meth) acrylate;
• (a7) formalin condensates of phenolic compounds;
• (a8) melamine and its formalin condensates;
• (a9) Condensates of aldehydes, such as dipentaerithritol and tripentaerithritol;
• (a10) polyglycerin; and
• (a11) Compounds in which some or all of the acti ven hydrogen atoms of the compounds (a6) to (a10) with no more than 10 monoepoxide compounds (b) per active Hydrogen atom are added.

Examples of monoepoxide compounds (b) which are described in the compounds (a3), (a5) and (a11) can be used NEN include alkylene (arylene) oxides such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, α-olefin oxides, epichlorethylene in it, epibromohydrin and monoglycidyl ether compounds, such as Butylglycidyl ether, phenylglycidyl ether and 2-ethylhexylgly cidyl ether. The added monoepoxide compounds can be in Combinations of two or more can be used. It can are either block or random addition types.  

The number of monoepoxide compounds added to (a3) gene should not average more than 10 per hydroxy group and in the case of (a5) and (a9) not more than 10 per active hydrogen atom. If the average Number of monoepoxide compounds over 10 is in in any case the cross-linked structure in the hardened Product loose; also its mechanical properties and its resistance to chemicals and what reduced. This is partly due to the fact that the hydrophilic nature of the cured product or the molecular weight of the part between neighboring crossbars network points is bound to be increased.

By changing the type, the addition form or the Addition amount of the monoepoxide compounds it is possible the viscosity of the mercapto compound (A), the miscibility with the polyepoxide compound (B) and the physical egg properties of the hardened products, such as their flexibility and hardness to regulate.

The preferred mercapto compound (A) is a mercap toverbindung (A1) with a chain structure and / or re Collection unit according to the following formula (2), which of the as Starting material compound (a) listed compounds received:

In Formula 2, "Q" is a group with the following formula:

the group -Z¹- (Z²) r-Z¹- represents a radical "X" (shown in formula 1), which has a chain structure and / or re has retrieval units; "Z¹" is an organic group; "s" means the number of "Q" groups attached to "Z¹"  and is an integer equal to 1 or 2; "Z²" is one organic group; and "r" represents the number of "Q-Z²" groups in the compound represented by formula (2) hung between "n", "r" and "s" is n = r + 2s.

The properties of the hardened epoxy resins present invention, such as mechanical strength and the Resistance to water and chemicals, in particular by using the hardening agent with the Mercapto connections (A1) improved. The reason for this is not completely clarified; however, it is believed to be on the following is due:

• (1) Compound (A1) has 5 or more mercaptans groups;
• (2) Compound (A1) has no ester linkages; and
• (3) since the compound (A1) has a chain structure and / or Repeat units included, the mercaptanhal lie groups "Q" at different positions in the back burr chain before. Many exist with this configuration cross-linked points in the hardened product what a dense three-dimensional network formed by the Ver bond (A1) and the polyepoxide compound (B).

Examples of the organic group "Z 1" in formula (2) include a residue in which the active hydrogen atoms have been removed from an organic group having one or two hydroxyl groups or a primary amine. Examples of the organic group "Z²" include a residue in which an active hydrogen atom has been removed from an organic group having a hydroxyl group or a secondary amino group. Examples of the mercapto compound (A1) include mercapto compounds prepared by the methods already described using the following compounds (1) to (8) of the aforementioned compounds (a1) to (a11). The compound in which "s" is equal to 2 in both terminal Z¹ (Q) _s groups according to formula (2) can be obtained when the compounds (3) and (4) are used as starting materials during the connection , where s is 1, can be obtained in the remaining examples:

• (1) sugar alcohols according to (a2);
• (2) Compounds in which some or all of the hydroxy groups of the sugar alcohols according to (a2) with no more than 10 Monoepoxide compounds (b) are added per hydroxyl group;
• (3) polyalkylene polyamines according to (a4);
• (4) compounds in which some or all are active Hydrogen atoms of the polyalkylene polyamines according to (a4) no more than 10 monoepoxide compounds (b) per active Hydrogen atom are added;
• (5) vinyl (co) polymers according to (a6) with a vinyl mono mer, which has a hydroxy group as a structural com component;
• (6) Formalin condensates of the phenolic compounds according to (a7);
• (7) polyglycerol according to (a10); and
• (8) compounds in which some or all are active Hydrogen atoms of the compounds (a6), (a7) or (a10) with no more than 10 monoepoxide compounds (b) per active Hydrogen atom are added.

The mercaptan equivalent (molecular weight divided by the number of mercaptan groups) becomes easy Change the connection type used (a) or the Ratio of the mercaptan conversion by the addition reaction of the hydrogen sulfide in the production of the Mercapto compound (A) regulated. The mercaptan equivalent the compound (A) is preferably 100 to 1000, more preferably 100 to 400. If the mercaptan equivalent is over 1000, the properties of the hardened product, like its Strength or water resistance, degraded while Compounds with a mercaptan equivalent below 100 heavy are to be produced.

Conventional polymercaptan compounds can be used as a component of the curing agent of the present invention be used, provided the polymercaptan compounds  does not affect the properties of the mercapto compounds (A) pregnant.

The epoxy resin composition of the invention contains the curing agent of the present invention with the Mer capto compound (A) and the polyepoxide compound (B). This Epoxy resin composition is typically a double pack system which contains a curing agent component with the Mer capto compound (A) and a main component with the poly epoxy compound (B). Both components are at Mixed use.

Examples of the polyepoxide compound (B) include the following (B1) to (B6); however, they are not on this limited if the epoxy compound is an epoxy group has that with the active hydrogen atom of the mercaptan group can react.

• (B1) polyepoxide compounds manufactured by Addi tion of a polyphenol such as bisphenol A, halogenated bis phenol A, bisphenol B, bisphenol AD, bisphenol F, halogen bisphenol F, resorcinol, hydroquinone, pyrogallol, Catechol, 4,4'-dihydroxybiphenyl and 1,5-hydroxynaphthalene with two or more equivalents of epichlorohydrin; or poly phenol epoxy resin compounds such as phenol novolac, brominated Novolac and Kresolnovolac;
• (B2) polyglycidyl ester polyepoxide compounds;
• (B3) polyglycidylamine polyepoxide compounds;
• (B4) polyepoxide compounds manufactured by Addi tion of polyhydric alcohols, such as hydrogenated bisphenol A, ethylene glycol, propylene glycol, tetramethylene glycol, ethyl lenoxide adduct of bisphenol A, propylene oxide adduct of bis phenol A, 2,2-dimethyrene propane, trimethyrene propane, Pentaeri thritol, dipentaerythritol and sorbitol, with two or more Equivalents of epichlorohydrin;
• (B5) alicyclic polyepoxy resin compounds; and
• (B6) heterocyclic polyepoxide compounds.

In the composition according to the invention, the following basic substances (C) and / or compounds (D)  with a phenolic hydroxyl group as curing accelerators are added.

The basic substances (C) contain amines (C1), Compounds (C2) with a protected amino group, the be converted into a free amino group by hydrolysis can, and / or phosphines (C3).

Specific examples of the amines (C1) include:

• aliphatic amines, such as n-butylamine, isobutylamine, Ethylene diamine, propylene diamine, hexamethylene diamine, 2,5-dime thylhexamethylene diamine, trimethylhexamethylene diamine, Diet hylaminopropylamine, methyliminobispropylamine, tri (methylami no) hexane and polyether diamine;
• - Polyethylene polyamines, such as diethylenetriamine, Triethy lentetramine, tetraethylene pentamine, pentaethylene hexamine;
• alicyclic amines, such as menthenediamine, bis (aminomas thyl) cyclohexane, bis (4-amino) -3-methyldicyclohexyl) methane, Diaminodicyclohexylmethane, isophoronediamine, norbornane diamine, N-aminoethylpiperazine;
• aromatic amines, such as aniline, diaminodiphenylme than, diaminodiphenyl sulfone, diaminodiethyldiphenylmethane; aliphatic aromatic amines such as m-xylene diamine;
• cyclic amines, such as piperazine or piperidine;
• Polyamide amines, such as condensation reaction products of polyethylene polyamines with polymerized fatty acids (Dimer acids);
• - Aliphatic tertiary amines, such as triethylamine, tri butylamine, diethylbutylamine, N, N-dimethylpropylamine, N, N, N ′, N′-tetramethylhexamethylene diamine;
• cyclic tertiary amines, such as N-methylpyridine, N-methylpyrrolidine, N, N'-dimethylpiperidine;
• alicyclic tertiary amines, such as 1,8-diazabicy clo (5,4,0) undeken-7,1,5-diazabicyclo (4,3,0) nonen-5,6-dibu tylamino-1,8-diazabicyclo (5,4,0) undeken-7;
• - Aliphatic aromatic tertiary amines, such as benzyl dimethylamine, dimethylaminomethylphenol, 2,4,6-tris (dimethy laminomethyl) phenol.

Specific examples of compound (C2) include ketimine compounds and oxazolidine compounds. The Ketimine compounds are made by a well known process manufactured, which the reaction of amines with a pri with amino groups under dehydrating conditions Ketones such as acetone, methyl ethyl ketone and methyl isobutylke clay, or aldehydes, such as acetaldehyde and propionaldehyde, includes. The oxazolidine compounds are also represented by a well-known process which is the implementation of amines with a hydroxyalkylamino group under dehydra tising conditions with ketones, such as acetone, methylet hylketone and methyl isobutyl ketone, or aldehydes such as Ace taldehyde and propionaldehyde.

Specific examples of phosphines (C3) include Triethylphosphine, tributylphosphine and triphenylphosphine.

If the basic substances (C) increase the Cure rate are added, the respective strong basic tertiary amines among the above written amines (C1) preferred. Amines with primary or secondary amino groups, which have active hydrogen atoms have before that can react with epoxy groups as this does not have the properties of the hardened Pro products, such as its mechanical strength or its durability resistance to water and chemicals.

Polyamide amines according to (C1), compounds (C2) with a protected amino group and phosphines (C3) are preferred, if the extension of the pot life according to the composition Mix the main component with the hardener component is desired.

If unprotected primary or secondary amino groups in these compounds (C2) with a protected amino group pe remain, the amino groups are preferred with for example monoepoxide compounds, isocyanate compounds, Acid anhydrides, acrylonitrile, acrylic acid or acrylic acids star pre-reacted to the pot life of the composition extend.  

If a connection (C2) with a protected amino group as a curing accelerator to form the epoxy resin is given, it activates the mercapto compounds (A) the curing agent component after the free amino groups were formed by hydrolysis due to the application moisture in the air. As a result, the Be start of the hardening reaction by the time it takes for the hydro lysis is needed, delayed, and it is possible to use the pot regulate time of composition.

Examples of the compound (D) include phenol, Octylphenol, nonylphenol, bisphenol A, bisphenol B, bisphe nol AD, bisphenol F, resorcinol, hydroquinone, pyrogallol, Catechol, naphthol, cresol, 4,4'-dihydroxybiphenyl, 1,5-hydroxynaphthalene and their condensation compounds with Formalin.

The hardening speed, the pot life and the Properties of the cured product can vary accordingly the application, the intended use or the intended use conditions by changing the type or amount of basic Substances (C) are regulated.

These basic substances can also be found in Kombina tion can be used. The basic substances (C) and / or the compounds (D) can be hardened from the outset middle component or be included as a third component be added at the time of use. If from are contained in the hardener component in advance, will generally be the maximum curing rate reached. If it is the third component at the time of Use can be added to the pot life by the time be extended, which is necessary to the Mercaptangrup to activate pen. The basic substances (C) and the Compounds (D) can be used alone or together however, they are preferably used together to form the Increase curing reaction rate.

You can choose to the composition of the invention wise pot life regulating agents (E) are added to  regulate the pot life of the composition in such a way that it is not too short. These can be connections (E1) with one or more carboxyl groups in the molecule, Lewis acids (E2) and / or amine complex salts of Lewis acids (E3) act.

The compounds (E1) include formic acid, vinegar acid, propionic acid, butyric acid, lactic acid, acrylic acid, Methacrylic acid, octylic acid, oleic acid, linoleic acid, stearin acid, oxalic acid, malonic acid, succinic acid, benzoic acid, Phthalic acid, trimellitic acid, pyromellitic acid, salicylic acid, Tartaric acid, sebacic acid, citric acid, dimer acid, acid hydride and mercaptoalkyl acid. According to the Lewis acids (E2) include fluoroborone, aluminum trichloride and iron tri chloride. Tough to the amine complex salts of Lewis acids (E3) len the complex salts of Lewis acids according to (E2) with Triet hylamine or tributylamine.

The process of adding or using the the pot time-regulating means (E) is similar to that of the compound gene (C) and / or (D). The funds (E) can be combined with the Compounds (C) and / or (D) are added.

The ratio of each component in the invention ß epoxy resin composition per 100 parts by mass of Polyep Oxide compound (B) is as follows: The hardening agent Component in the form of the mercapto compounds (A) is typically usually in an amount of 5 to 200 parts by mass before prefers from 30 to 100 parts by mass, before; the basic sub punches (C) are typically not more than 100 dimensions rush, preferably with 0.5 to 50 parts by mass, before; the Compounds (D) are typically no more than 50 Parts by mass, preferably with 0.4 to 40 parts by mass, before; and the means regulating the pot life (E) are typical usually not more than 10 parts by mass, preferably with 0.01 to 5 parts by mass.

To the hardener component or the main compo elements in the composition according to the invention can be chosen as different additives are given. These include  Desiccants, extenders, plasticizers, antioxidants, UV absorbers, adhesion-improving agents, Thixotro agents, adhesion promoters, solvents, reactive thinners agents, pigments, dispersions, flame retardants, electrically conductive fillers and thickeners.

The present invention is illustrated by the following Examples described in more detail. All partial and percentage data relate to the mass, if not different is specified.

Synthesis example 1

182 parts sorbitol, 1110 parts epichlorohydrin and 15 Parts of benzyltrimethylammonium chloride were placed in a reak given vessel. Then 480 parts of aqueous natri Umhydroxid added in portions to this mixture, wherein the temperature was kept below 40 ° C, and then for 3 Aged at 40 ° C for hours.

The contents were transferred to a separatory funnel, washed three times with 1000 parts of water, the remaining Epichlorohydrin distilled off under reduced pressure and filtered to give intermediate M1. The Intermediate M1 had an average molecular weight (Number average) of 440 g / mol and a viscosity of 1,300 cP (measured with a B-type viscometer at 25 ° C). It this connection was found to be 58% terminal Contained epoxy groups.

440 parts of intermediate M1, 800 parts of methanol and 16 parts of triethylamine were put in a reaction vessel ben and nitrogen exchange carried out. 400 parts of welding Hydrogen sulfide was then introduced into this under reduced pressure Blown mixture, keeping the temperature below 30 ° C has been. After 5 hours of aging at 30 ° C was not reversed set hydrogen sulfide absorbed in an alkali solution and the mixture is filtered, the polymercaptan compound I was obtained.

The polymercaptan compound I had a medium one  Molecular weight (number average) of 630 g / mol and a Vis viscosity of 5200 cP (measured with a B-type viscometer at 25 ° C); it was a yellowish brown, viscous se liquid. The average functionality (number average) the mercaptan groups were found to be 5.7. The middle Functionality (number average) defines the average number of functional groups in a connection.

Synthesis example 2

182 parts of sorbitol and 4 parts of potassium hydroxide were added placed in a reaction vessel. Then 348 parts of Propy lenoxid (abbreviated "PO") gradually blown into this mixture sen, keeping the temperature of the contents below 80 ° C has been. The content was aged at 110 ° C for 4 hours and then filtered to obtain the intermediate M21 has been. The intermediate M21 had a medium molecule Lar weight (number average) of 530 g / mol and a viscosity of 1700 cP (measured with a B-type viscometer at 25 ° C); it turned out to be the PO-Addi tion product of sorbitol, containing 19% hydroxyl groups, acted.

Next, 530 parts of the intermediate M21, 1110 parts epichlorohydrin and 15 parts benzyltrimethyl put ammonium chloride in a reaction vessel, 480 parts Sodium hydroxide added to this mixture in portions, keeping the temperature below 40 ° C, and then 3 Aged at 40 ° C for hours.

The contents were transferred to a separatory funnel, washed three times with 1000 parts of water, the remaining Epichlorohydrin distilled off under reduced pressure and then filtered to give intermediate M22 de. The intermediate M22 had an average molecular weight weight (number average) of 790 g / mol and a viscosity of 1,800 cP (measured with a B-type viscometer at 25 ° C); the content of terminal epoxy groups was found to be 32% immt.  

790 parts of the intermediate M22, 1600 parts of metha nol and 16 parts of triethylamine were placed in a reaction vessel given and nitrogen exchange carried out. Then were 400 parts of hydrogen sulfide under reduced pressure in this mixture is blown, the temperature below 30 ° C was held. After aging for 5 hours at 30 ° C unreacted hydrogen sulfide in an alkali solution absorbed and then the mixture filtered, the poly mercaptan compound II was obtained. The polymercaptanver bond II had an average molecular weight (number with tel) of 1040 g / mol and a viscosity of 6400 cP (measured with a B-type viscometer at 25 ° C); it acted a light yellow, viscous liquid with a medium functionality (number average) of the mercaptan groups of 5.8.

Synthesis example 3

182 parts of sorbitol and 4 parts of potassium hydroxide were added placed in a reaction vessel. Then 264 parts of Ethy lenoxid (abbreviated "EO") gradually blown into this mixture sen, keeping the temperature of the contents below 80 ° C has been. The content was aged at 110 ° C for 4 hours and then filtered to obtain the intermediate M31 has been. The intermediate M31 had a medium molecule Lar weight (number average) of 450 g / mol and a viscosity of 1500 cP (measured with a B-type viscometer at 25 ° C); it turned out to be the EO-Addi tion product of sorbitol, containing 22% hydroxyl groups, acted.

Next, 450 parts of the intermediate M31, 1110 parts epichlorohydrin and 15 parts benzyltrimethyl put ammonium chloride in a reaction vessel. Then were 480 parts of sodium hydroxide in portions to this mixture given, the temperature was kept below 40 ° C, and then aged for 3 hours at 40 ° C.

The contents were transferred to a separatory funnel,  washed three times with 1000 parts of water, the remaining Epichlorohydrin distilled off under reduced pressure and filtered to give the intermediate M32. The Intermediate M32 had an average molecular weight (Number average) of 700 g / mol and a viscosity of 1800 cP (measured with a B-type viscometer at 25 ° C); the Ge terminal epoxy groups was found to be 36%.

700 parts of the intermediate M32, 1,600 parts of metha nol and 16 triethylamine were placed in a reaction vessel and nitrogen exchange carried out. 400 parts of sulfur Hydrogen was then put into this under reduced pressure Blown mixture, keeping the temperature below 30 ° C has been.

After 5 hours of aging at 30 ° C, the was not converted hydrogen sulfide absorbed into an alkali solution beers and then filtered, the polymercaptan compound III was obtained. The polymercaptan compound III had an average molecular weight (number average) of 890 g / mol, a viscosity of 6500 cP (measured with a B-type Vis cosimeter at 25 ° C); it was a light yellow, viscous liquid with medium functionality (Zah lenmittel) of the mercaptan groups of 5.8.

Synthesis example 4

146 parts of triethylene tetramine and 4 parts of potassium hydro xid were placed in a reaction vessel. Then 348 Gradually blow PO into this mixture, taking the Content temperature was kept below 80 ° C. The In stop was aged for 4 hours at 110 ° C and then filmed tert, whereby the intermediate M41 was obtained. The Intermediate M41 had an average molecular weight (Number average) of 490 g / mol and a viscosity of 1500 cP (measured with a B-type viscometer at 25 ° C); it put was found to be a PO addition product from Triethylenetetramine, containing 20% hydroxyl groups, han delte.  

Next, 490 parts of the intermediate M41, 1110 parts epichlorohydrin and 15 parts benzyltrimethyl put ammonium chloride in a reaction vessel, 480 parts Sodium hydroxide added to this mixture in portions, keeping the temperature below 40 ° C, and then aged for 3 hours at 40 ° C.

The contents were transferred to a separatory funnel, washed three times with 1,000 parts of water, then the lead epichlorohydrin distilled off under reduced pressure and filtered to give intermediate M42. The intermediate M42 had an average molecular weight (Number average) of 755 g / mol and a viscosity of 1700 cP (measured with a B-type viscometer at 25 ° C); the Ge terminal epoxy groups was found to be 33%.

755 parts of intermediate M42, 1600 parts of metha nol and 16 parts of triethylamine were placed in a reaction vessel loaded and nitrogen exchange performed. Then were 400 parts of hydrogen sulfide under reduced pressure in this mixture is blown, the temperature below 30 ° C was held.

After 5 hours of aging at 30 ° C, the was not converted hydrogen sulfide absorbed into an alkali solution beers and then filtered the mixture, the polymer cap Tan compound IV was obtained.

The polymercaptan compound IV had a medium one Molecular weight (number average) of 980 g / mol, a viscose 9200 cP (measured with a B-type viscometer at 25 ° C); it was a light yellow, viscous liquid with a medium functionality (number average) Mercaptan groups of 5.8.

Examples 1-4 Comparative Examples 1 and 2

In Examples 1-4, the respective polymer captan compounds I-IV were combined with a bisphenol A polyepoxide compound (EPIKOTE 828 ^™ , available from Yuka-Shell Epoxy Co.) and a curing accelerator (2,4,6-tris (dimethyla minomethyl) phenol) and then evaluating the pot life and curing properties of each of the mixtures and also the mechanical properties and resistance to water and chemicals of each cured product using the following procedures. In the comparative examples, the evaluations were carried out in a manner similar to that in the examples. However, in Comparative Example 1, instead of the polymercaptan compounds I-IV, dipentaerythritolhexathioglycolic acid ester (the polymercaptan compound V, for comparison) and in Comparative Example 2 CAPCURE 3-800 ^TM (available from Hoescht Corp., with an average functionality (number average) of the mercaptan groups of 5. 8) (the polymercaptan compound VI, for comparison). The formulation was 100 parts of compounds I-VI and 5 parts of 2,4,6-tris (dimethylaminomethyl) phenol per 100 parts of EPIKOTE 828 ^™ . The results of the evaluations are shown in Table 1.

Evaluation procedure Pot life

Immediately after mixing, 100 g of each mixture was added a thermostatic chamber at a test temperature hold and the temperature rise in the curing reactions measured by a temperature recording device. The Pot life was defined as the time in which the middle part the mixture reached the temperature {To + (Tm - To) / 3} ° C, where "To" is the test temperature and "Tm" is the maximum reached represent temperature.

Hardening property

Immediately after mixing, each mix was included distributed in a thickness of 300 microns on a glass plate. The Dry tack was defined as the time in which the Surface of the coating under a constant test temperature temperature no longer exhibited any stickiness.  

Mechanical properties

The tensile strength of the resulting product was reduced to 7-day curing of each mixture at room temperature in excess in accordance with the procedure described in JIS K-7113 measured.

Resistance to water and chemicals

Each of the blends was made into a disc shape a diameter of 12 mm and a thickness of 8 mm cast and after seven days of curing at room temperature for 7 Days at room temperature in those listed in Table 1 Test solutions immersed. Then the mass change measured. The mass change is considered a mass increase, though not otherwise specified, defined.

Table 1

Examples 5-10

The formulations used in these examples were polymercaptan compounds II, EPIKOTE 828 ^™ , the respective curing accelerators listed in Table 2 (instead of the 2,4,6-tris (dimethylaminomethyl) phenol used in Examples 1-4), acetic acid (a Pot time regulating agent) and NIKANOL Y-50 ^™ (a plasticizer available from Mitsubishi Gas Chemical Co., the formaldehyde condensate from xylene). The curing properties and pot life of each mixture of these components as well as the mechanical properties and the resistance to water and chemicals of each of the resulting cured products were evaluated. The evaluation results are shown in Table 2.

Table 2

The curing agent and the epoxy resin composition of the present invention have improved rapid hardening properties and improved low-temperature curing properties compared to conventional hardening agents based on mercaptan. In addition, the properties of conventional mercaptan based curing agents such as the mechanical properties and resistance to what water and chemicals of the resulting hardened products, much less than that of the present invention. Des half the present invention is then preferably used det if quick hardening properties or low temperature hardening properties or the other egg mentioned above properties of the hardened products are required.

This is due to the advantages mentioned above hardener according to the invention and the epoxy according to the invention Resin composition useful in the following applications:

• (1) Use as a binder: Binder for FRP (Fiber-reinforced plastics) or for connecting concrete and sheet steel, which in earthquake-proof reinforcement con structures are used, resins for use as stra plasters and resins for use in water penetrating plasters and the like;
• (2) Use as a coating, seal and the like Liches: concrete reinforcement, water repellent for Concrete, sealant, potting agent, corrosion resistant Coatings, coating material for floors, primer and electrical applications (such as laminates for ge printed circuits, sealants for semiconductors and Insulation); and
• (3) Use as molding resins: resins for molding or Resin models.

Claims (15)

1. curing agent for epoxy resins containing a mercapto compound (A) according to the following formula (1): in which "n" is an integer equal to or greater than 5 and "X" is a radical in which "n" hydrogen atoms have been removed from a compound (a) having "n" or more active hydrogen atoms. 2. The curing agent according to claim 1, wherein the mercap to compound (A) corresponds to the following formula (2): in which "Q" is a group of the following formula: -Z¹- (Z²) r-Z¹- represents the radical "X", the radical "X" being a radical of a compound having a chain structure; "Z 1" is an organic group; "s" means the number of "Q" groups attached to "Z 1" and an integer equal to 1 or 2; "Z²" is an organic group; and "r" represents the number of "Z²-Q" groups and is an integer that satisfies the relationship n = r + 2s. 3. A curing agent according to claim 1, wherein compound

• (a) one of the compounds
• (a1) saccharides;
• (a2) sugar alcohols;
• (a3) compounds in which some or all of the hydroxyl groups of the saccharides (a1) or sugar alcohols (a2) are added with not more than 10 monoepoxide compounds (b) per hydroxyl group;
• (a4) polyalkylene polyamines having 5 to 8 active hydrogen atoms; and or
• (a5) the compounds in which some or all of the active hydrogen atoms of the polyalkylene polyamines (a4) are added with no more than 10 monoepoxide compounds (b) per active hydrogen atom.

4. A curing agent according to claim 1, wherein the mercap to compound (A) a mercaptan equivalent of 100 to 1000 having. 5. Epoxy resin composition containing:
a curing agent for epoxy resins, containing a mercapto compound (A) according to the following formula (1): in which "n" is an integer equal to or greater than 5 and "X" is a radical in which "n" hydrogen atoms have been removed from a compound (a) having "n" or more active hydrogen atoms; and a polyepoxide compound (B). 6. The epoxy resin composition according to claim 5, wherein the polyepoxide compound (B) is one of the compounds

• (B1) polyepoxide compounds produced by addition of one of the polyphenols bisphenol A, halogenated bisphenol A, bisphenol B, bisphenol AD, bisphenol F, halogenated bisphenol F, resorcinol, hydroquinone, pyrogallol, catechol, 4,4′-dihydroxybiphenyl and / or 1,5-hydroxynaphthalene with two or more equivalents of epichlorohydrin;
• (B2) one of the polyphenol epoxy resin compounds phenol novolac, brominated novolac and / or cresol novolac;
• (B3) polyglycidyl ester polyepoxide compounds;
• (B4) a polyglycidylamine polyepoxide compound;
• (B5) polyepoxide compounds prepared by addition of one of the polyhydric alcohols hydrogenated bisphenol A, ethylene glycol, propylene glycol, tetramethylene glycol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, 2,2-dimethyrene propane, trimethyrene propane, pentaerythritol and dipentaerythritol Sorbitol with two or more equivalents of epichlorohydrin;
• (B6) alicyclic polyepoxy resin compounds;
  and or
• (B7) heterocyclic polyepoxide compounds.

7. The epoxy resin composition according to claim 5, wherein the ratio of the mercaptan equivalent of mercaptoverbin Formation (A) to the epoxy equivalent of the polyepoxide compound (B) is 1 / 0.5 to 1/2. 8. The epoxy resin composition according to claim 7, which also one of the basic substances (C) amines (C1), Ver bonds (C2) with a protected amino group which can be protected by Hydrolysis can be converted into a free amino group, and / or contains phosphines (C3) as curing accelerators. 9. The epoxy resin composition according to claim 7, which also a compound (D) with a phenolic hydrox yl group contains as a curing accelerator. 10. The epoxy resin composition according to claim 5, which  also compounds (E1) with one or more carboxyl groups pen, Lewis acids (E2) and / or amine complex salts from Lewis acids (E3) as an agent regulating pot life (E) holds. 11. A process for producing a hardened epoxy resin which comprises reacting a polyepoxide compound (B) with a hardening agent for epoxy resin containing a mercapto compound (A) according to the following formula (1): in which "n" is an integer equal to or greater than 5 and "X" is a radical in which "n" hydrogen atoms have been removed from a compound (a) having "n" or more active hydrogen atoms. 12. Process for making a hardened epoxy The resin according to claim 11, wherein the mercapto compound (A) and the polyepoxide compound (B) in the presence of a base The substance (C) implemented as a curing accelerator the, whereby the basic substance (C) is a Amine (C1), a compound (C2) with a protected amino group which is converted into a free amino group by hydrolysis can be performed, and / or a phosphine (C3). 13. Process for making a hardened epoxy The resin according to claim 11, wherein the mercapto compound (A) and the polyepoxide compound (B) in the presence of a verb dung (D) with a phenolic hydroxyl group as a curing implemented faster. 14. Process for making a hardened epoxy The resin according to claim 11, wherein the mercapto compound (A)  and the polyepoxide compound (B) in the presence of verbin dung (E1) with one or more carboxyl groups, Lewis acids (E2) and / or amine complex salts of Lewis acids (E3) than that Pot life regulating agent (E) are implemented. 15. Cured epoxy resin containing a product of a curing reaction between a polyepoxide compound (B) and a curing agent for an epoxy resin containing a mercapto compound (A) according to the following formula (1): in which "n" is an integer equal to or greater than 5 and "X" is a radical in which "n" hydrogen atoms have been removed from a compound (a) having "n" or more active hydrogen atoms.