JPS6056168B2 - Manufacturing method of amine modified product - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for producing amine-modified products.

More specifically, it is suitable as an epoxy resin curing agent that cures epoxy resin in a short time not only at room temperature but also at low temperatures of 0 to 5°C, and provides a cured product with excellent flexibility, water resistance, and adhesive properties. The present invention relates to a method for producing an amine-modified product. Epoxy resins have excellent adhesion and anticorrosion properties, and are therefore used in an extremely wide range of applications, including paints, castings, adhesives, and civil engineering and construction applications.

With the expansion of this use, epoxy resins are used under various curing conditions, but the most common method is heating or curing at room temperature. In applications such as thermal coatings, adhesives, and civil engineering and construction, there is an increasing demand for epoxy resin curing agents that can quickly cure epoxy resins even at low temperatures of 0 to 5 degrees Celsius in winter, and provide cured products with good physical properties. It's here. Modified amines (amine adducts, such as glycidyl ether added to amines) or mixtures of amines and phenols are known as curing agents that can quickly cure epoxy resins even at low temperatures. Cured epoxy resin is very hard and lacks flexibility.

For this reason, when used in paints, adhesives, etc., the paint film or adhesive layer is brittle and weak against impact, and cast products are prone to cracking. In addition, condensates of phenols, aliphatic polyamines, and aldehydes (British Patent Specification No. 886767), condensates of phenols, xylene diamine, and aldehydes (Japanese Patent Publication No. 49-4
86 No. 86) or condensates of phenols with 1,3-bisaminomethylcyclohexane or 2,2,4-trimethylhexamethylenediamine and aldehydes (Japanese Patent Publication No. 52-204 (1)), etc. Epoxy resin curing agents are also known, but like the above-mentioned modified amines, these have excellent curing speeds at normal and low temperatures, but the flexibility of the cured product is not sufficient.

The present inventors have discovered that an amine suitable as an epoxy resin curing agent can rapidly cure an epoxy resin not only at room temperature but also at a low temperature of 0 to 5°C, and provide a cured product with excellent flexibility and other physical properties. The present invention was achieved as a result of extensive research aimed at finding a method for producing modified products.

That is, the present invention uses phenols (A), bishexamethylenetriamine (B1), N-ethylhexamethylenediamine (B2), and hexamethylenediamine (B3).
) and an amine mixture (B) containing aldehydes (C)
This is a method for producing an amine-modified product, which is characterized by reacting with. In the present invention, the amine mixture (B) used for producing the amine-modified product is bis-hexamethylene triamine (B1), N-ethylhexamethylene diamine (B2).
) and hexamethylene diamine (B3).

The compositions of (B1), (B2) and (BJ) in (B) are not particularly limited, but are, for example, as follows based on the total weight of (B1) to (B3). Bishexamethylenetriamine (B1) 20 to 30% by weight (especially 30 to 7% by weight) N-ethylhexamethylenediamine (B2) 10 to 7% by weight (especially 15 to 6% by weight) Hexamethylenediamine (
B3) Amine mixtures (B) containing 1 to 3 % by weight (in particular 3 to 15 % by weight) (B1), (B2) and (B3) can also be used for the production of hexamethylene diamine from acrylonitrile [e.g. Reduction method: 1 Chemistry of synthetic resins 1 (new edition) J1 (1930 edition), written by Tadahiro Miba, published by Gihodo, see page 311]
It may be a by-product (distillation residue) obtained in the process or an amine mixture containing the same, and the composition of the by-product is usually as follows.

Bishexamethylene triamine 30-7% by weight N-ethylhexamethylene diamine 15-6% by weight Hexamethylene diamine 3-15% by weight Even if this by-product further contains 15% by weight or less of strength soda. However, it is preferable to remove the abrasive soda by a method such as distillation before use.

If the amount of sodium hydroxide exceeds 15% by weight, the water resistance and acid resistance of the cured epoxy resin will deteriorate. Since this by-product can be obtained economically, and when using an epoxy curing agent containing a reaction product made from this material (in particular, the by-product excluding the hydric soda), the cured product It is particularly preferred because of its excellent water resistance and flexibility.

At least one of (B1), (B2) and (B3) may be added to this by-product to form an amine mixture (B).

In the present invention, it is used in the production of amine-modified products (B1
), (B2) and (B3) may be mixtures of these and other amines, in which case the other amines include aliphatic polyamines (ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine). , tetramethylene diamine, etc.), polyamines with aromatic rings (xylylene diamine), alicyclic polyamines (isophorone diamine, etc.)
, aromatic polyamine (m-phenylenediamine, 4,4
-diaminediphenylmethane, etc.).

Preferred among these are aliphatic polyamines.
When using an amine mixture containing (B1), (B2) and (B3), the total weight of (B1) to (B3) is usually 2% by weight or more based on the weight of the amine mixture (B), Preferably it is 5% or more. In the present invention, examples of phenols used in the production of amine-modified products include phenol and substituted phenols substituted with at least one type of substituent such as an alkyl group, an aryl group, an aralkyl group, and an alkyl group. It will be done.

Examples of the alkyl group include alkyl groups having 1 to 20 carbon atoms, such as methyl, butyl, tert-butyl, octyl, nonyl, and dodecyl. Examples of the aryl group include a phenyl group, examples of the aralkyl group include benzyl, phenethyl, and cumyl groups, and examples of the aralkyl group include chlorine and bromine groups. Examples of substituted phenols include alkylphenols such as ortho, meta and valaclesol, butylphenol, octylphenol, nonylphenol, xylenol, dinonylphenol; arylphenols such as phenylphenol, aralkylphenols such as benzylphenol, cumylphenol, mono- or distyrenated Phenol; halogenated phenol such as chlorophenol,
Examples include bromophenol. Phenols may be used in combination. Furthermore, not only monohydric phenols but also polyhydric phenols (resorcinol, catechol, hydroquinone, bisphenol, etc.) can be used. Among the above phenols, preferred are phenol and alkylphenols (especially ortho, meta and valaclesol, octylphenol and nonylphenol). Examples of aldehydes used in the production of amine-modified products in the present invention include formaldehyde, paraformaldehyde, acetaldehyde, valaldehyde, propionaldehyde, and chloral.

Among them, formaldehyde, paraformaldehyde and acetaldehyde are preferred, and formaldehyde is particularly preferred. Formaldehyde can be used as an aqueous solution or as a solution in an organic solvent such as methanol, and this method of use is preferred. In the present invention, phenols (A
) and an amine mixture (B) containing bishexamethylenetriamine (B1), N-ethylhexamethylenediamine (B2) and hexamethylenediamine (B3),
When reacting aldehydes (C), (A) and (B)
) and (C) molar ratio (A) (B) (C) = 1:
0.3-3:0.3-3, preferably 1:1-3:1
It is 3.

In the above molar ratio, the amount of aldehyde (C) is sufficient as long as it can bind the amine mixture (B) and phenol (A), and the number of moles of (C) is determined by the amount of (B) or (
It is not preferable to add in excess of the number of moles of A).
If the amount of the amine mixture (B) is less than 0.3 mol, the viscosity of the reaction product will be very high, and the flexibility of the cured epoxy resin will not be sufficient.
If the amount exceeds mol, the curing speed of the epoxy resin at room temperature and low temperature decreases, and it is not sufficient as a curing agent. In the present invention, the method for reacting (A), (B), and (C) is generally (1) adding aldehydes (C) to a mixture of phenols (A) and amine mixture (B), and reacting. (2) Reacting (A) and (C) in advance,
A method of reacting the obtained reactant with (B) and (3)
) A method is available in which (A), (B), and (C) are reacted simultaneously.

Among these methods, methods (1) and (2) are preferred. In this case, the reaction temperature is not particularly limited, but when adding aldehydes, it is usually carried out at 40°C or lower, and after the total amount of aldehydes are added, it is preferable to raise the temperature to about 70 to 100°C to complete the reaction. . After the reaction is completed, the obtained product is heated (40°C) under normal pressure or reduced pressure if necessary.
~120°C) to remove moisture and unreacted substances. The amine-modified product obtained by the present invention may contain unreacted J(A) and/or (B). The amine modified product obtained by the present invention usually has an amine value of 200 to 6001 and a viscosity (at 25°C) of 500 to 30.
000CpS.

Further, the amine-modified product obtained according to the present invention can be represented by the following general formula (1) [provided that phenol is used as (A) and formaldehyde is used as (C)]. (wherein A is an amine residue, R is hydrogen or -CH2
-A-H, m, m″ are each integers from 0 to 3, m+m″
= 1 to 3, n is 0 or an integer of 1 or more, and when m'' is 0, n is an integer of 1 or more.) In general formula (1), preferable ones are m = 0, n = 0 and m ″=1 to 3.
In this case, the curved structure is shown below. When m″=1: The amine-modified product obtained by the present invention is useful as an epoxy resin curing agent.

The epoxy resin to be used as a curing agent may be any ordinary one, for example, as described in Pa. 1 Chemistry of Synthetic Resins (New Edition) J (1930).
The epoxy resin described in Tadahiro Miba, published by Gihodo, pages 371 to 392 can be used. Specifically, examples include glycidyl-type epoxy resins (bisphenol-based, polyglycol-based, ester-based, etc.) and non-glycidyl-type epoxy resins (alicyclic-based, etc.). Among these, preferred are bisphenol-based epoxy resins. The appropriate blending ratio of the amine modified product to the epoxy resin is within the range of 0.5 to 1.5 amino active hydrogen equivalents of the curing agent per 1 epoxy equivalent of the epoxy resin. When using the amine-modified product, the epoxy resin and the amine-modified product may be used as they are, or they may be mixed in the presence of a conventionally used known solvent; Methods such as mixing and using one of the two as a mulchion are used.

The curing method may be at a low temperature such as 0 to 5°C, at room temperature, or by heating, and can be selected depending on the application. The amine-modified product in the present invention may be used in combination with other known curing agents if necessary, and in that case, the content of the amine-modified product in the present invention is usually 2% by weight in the total curing agent.
That's all.

Examples of other known curing agents include polyamide amines, modified amines (e.g. polyamines with monoepoxy compounds,
Examples include epoxy resins or those to which acrylonitrile, etc. have been added. The amine-modified product obtained by the present invention can also be a reaction product obtained by condensing polyamines other than (B1), (B2) and (B3) with phenols and aldehydes, or an uncondensed product. It may be used in combination with various modified polyamines. In these cases, the curing agent of the present invention is usually used when the total amount of (B1) to (B3) in all amines is 2, calculated in the form of unmodified polyamine.
They are mixed at a ratio of 0% by weight or more. Furthermore, the amine-modified product of the present invention can be used with the addition of auxiliary agents such as curing accelerators such as phenols and tertiary amines, fillers or extenders such as pigments, bituminous substances, glass fibers, aluminum powder, and silica gel. can. The amine-modified product obtained by the present invention can rapidly cure epoxy resins not only at room temperature but also at low temperatures such as 0 to 5°C, and the cured epoxy resin has good adhesiveness and water resistance, and is particularly flexible and Excellent wet surface adhesion.

The amine-modified products obtained according to the present invention are important as epoxy resin curing agents for paints, civil engineering and construction applications, and adhesives, but can also be used for casting and laminated resin applications.

The amine modified product according to the invention can be used in the method of the invention (
An amine obtained by using diaminocyclohexane, which is a by-product (first distillation fraction) in the production of hexamethylene diamine, or an amine mixture containing the same instead of the amine mixture containing B1), (B2), and (B3). It has a low viscosity and a light color when compared to modified products. The present invention will be explained below with reference to Examples, but the present invention is not limited thereto.

. Examples 1 to 3 A reaction vessel equipped with a stirrer, a thermometer, a dropping device, and a reflux device is charged with an amine component and phenols and mixed thoroughly, and an aldehyde (e.g., 37% formaldehyde aqueous solution) is added to the mixture at 40°C. It was gradually added dropwise.

After the dropwise addition was completed, the temperature was raised to 80°C, and the reaction was continued at the same temperature for 1 to 5 hours. After the reaction was completed, the reaction was carried out under reduced pressure at a temperature of 40 to 60°C (
For example, 15-30rr1 mHg) was dehydrated to obtain amine-modified products (Examples 1-6). The amine value and viscosity of these amine-modified products were measured. Table 1 shows the raw material composition and analytical values of the amine modified product.

Performance test 1 Epoxy resin (
Epicoat 82 (epoxy equivalent weight 1901, manufactured by Shell Kagaku Co., Ltd.) was cured, and the physical properties of the cured product were measured.

Claims (1)

[Scope of Claims] 1. Phenols (A), bishexamethylenetriamine (B_1), N-ethylhexamethylenediamine (
A method for producing an amine-modified product, which comprises reacting an amine mixture (B) containing B_2) and hexamethylene diamine (B_3) with an aldehyde (C). 2 Based on the total weight of (B_1) to (B_3), (B
The manufacturing method according to claim 1, wherein _1) is 20 to 80%, (B_2) is 10 to 70%, and (B_3) is 1 to 30%. 3. The manufacturing method according to claim 1 or 2, wherein the total weight of (B_1) to (B_3) is 20% or more of the weight of (B). 4 The molar ratio of (A), (B) and (C) is (A):(B
):(C)=1:0.3-3:0.3-3, the manufacturing method according to any one of claims 1 to 3. 5. Claim 1, wherein the amine mixture (B) is a by-product obtained when producing hexamethylene diamine from acrylonitrile or an amine mixture containing the same.
The manufacturing method according to any one of Items 1 to 4.