JP2019031644A - Polyolefin resin aqueous dispersion and method for producing the same - Google Patents

Abstract

To provide a cationic polyolefin resin aqueous dispersion, which can form a coat having excellent hot-water resistance and chemical resistance.SOLUTION: A polyolefin resin aqueous dispersion contains a polyolefin resin (A) and a crosslinker (B) dispersed in an aqueous medium. The polyolefin resin (A) contains an N-substituted cyclic imide unit, where an N-substituted group of the unit contains a primary and/or secondary amino group.SELECTED DRAWING: None

Description

  The present invention relates to an aqueous polyolefin resin dispersion and a method for producing the same.

Polyolefin resins represented by polyethylene and polypropylene are excellent in various properties such as mechanical properties, transparency, electrical properties, surface gloss, chemical resistance, water resistance, solvent resistance, etc. It is used in large quantities for a wide range of purposes such as household goods.
As a method of using a polyolefin resin, it is known that a polyolefin resin is processed into a solution or an aqueous dispersion and used as a coating agent. In the coating agent of polyolefin resin, non-halogenation and VOC reduction are being promoted from the viewpoint of environmental protection, and attempts to replace the solvent-based coating agent with an aqueous coating agent such as an aqueous dispersion have become active. Yes.

  As an aqueous dispersion of polyolefin resin, an anionic aqueous dispersion obtained by neutralizing a polyolefin resin containing an acid component with a basic compound is generally known. However, in the acidic region, the anionic aqueous dispersion may easily aggregate the resin particles in the aqueous dispersion and may not be able to maintain a stable form.

  On the other hand, as an aqueous dispersion of a cationic polyolefin resin, Patent Document 1 discloses an aqueous dispersion obtained by neutralizing a polyolefin resin containing an amino group in a side chain with an acidic compound.

International Publication No. 2010/098331

However, the coating film formed using the aqueous dispersion disclosed in Patent Document 1 sometimes has insufficient hot water resistance and chemical resistance.
An object of the present invention is to solve these problems and to provide an aqueous dispersion of a cationic polyolefin resin, which can form a coating film excellent in hot water resistance and chemical resistance. And

As a result of intensive studies to solve the above-mentioned problems, the present inventors have used a polyolefin resin having a primary and / or secondary amino group in the side chain, and contains a crosslinking agent in the aqueous dispersion. As a result, the inventors have found that the above problems can be solved and have reached the present invention.
That is, the gist of the present invention is the following (1) to (7).
(1) An aqueous dispersion in which a polyolefin resin (A) and a crosslinking agent (B) are dispersed in an aqueous medium, wherein the polyolefin resin (A) contains an N-substituted cyclic imide unit, An aqueous polyolefin resin dispersion, wherein the N-substituent contains primary and / or secondary amino groups.
(2) The aqueous polyolefin resin dispersion according to (1), wherein the N-substituent is a substituent represented by the following general formula (I).
_{-C n H 2n-m + 1} (NRR) m (I)
(In the formula, n and m represent natural numbers of 1 to 10, R is an arbitrary atomic group, and one or more of all R in the N-substituent is H.)
(3) The polyolefin resin aqueous dispersion according to (1) or (2), wherein the content of the N-substituted cyclic imide unit in the polyolefin resin (A) is 0.1 to 30% by mass.
(4) The polyolefin resin aqueous dispersion according to any one of (1) to (3), wherein the polyolefin resin further contains a (meth) acrylate unit.
(5) The aqueous polyolefin resin dispersion according to any one of (1) to (4), wherein the crosslinking agent (B) contains a functional group that reacts with an amino group.
(6) The functional group that reacts with an amino group is at least one selected from the group consisting of an acid anhydride group, an epoxy group, an isocyanate group, a blocked isocyanate group, and a carbamide group. Polyolefin resin aqueous dispersion.
(7) A method for producing the aqueous polyolefin resin dispersion described in (1) above, wherein in the synthesis of the polyolefin resin (A), a protected primary and / or protected secondary amino group; It comprises a step of reacting an amino compound (Q) containing an unprotected primary amino group with an unsaturated carboxylic acid anhydride unit of an unsaturated carboxylic acid anhydride-modified polyolefin resin (P). A method for producing an aqueous dispersion of polyolefin resin.

  In the polyolefin resin constituting the aqueous dispersion of the present invention, since the N-substituent of the N-substituted cyclic imide unit contains a reactive primary and / or secondary amino group, the polyolefin resin is modified by a crosslinking agent in the aqueous dispersion. Quality is possible. And the aqueous dispersion of this invention containing these can be uniformly apply | coated with respect to a wide variety of base materials, and the coating film obtained is adhesiveness, adhesiveness, hot water resistance, chemical resistance. Excellent heat resistance. Furthermore, since the aqueous dispersion of the present invention is aqueous, it is excellent in environmental conservation.

Hereinafter, the present invention will be described in detail.
<Polyolefin resin (A)>
The aqueous polyolefin resin dispersion of the present invention is obtained by dispersing a polyolefin resin (A) and a crosslinking agent (B) in an aqueous medium.
The polyolefin resin (A) in the present invention has an olefinic hydrocarbon unit and an N-substituted cyclic imide unit, and is N-substituted from the viewpoint of facilitating aqueous dispersion and reactivity with a crosslinking agent. A primary and / or secondary amino group is contained in the N-substituent of the cyclic imide unit.

  The olefinic hydrocarbon unit constituting the polyolefin resin (A) preferably has 2 to 6 carbon atoms, and includes ethylene, propylene, 1-butene, isobutene, 1-pentene, 4-methyl-1-pentene, 3 Examples include alkenes such as -methyl-1-pentene and 1-hexene, and dienes such as butadiene and isoprene, and may have a plurality of these units. Among them, the olefinic hydrocarbon unit is preferably ethylene, propylene, 1-butene, or isobutene, and more preferably ethylene or propylene, from the viewpoint of ease of resin production, adhesion to various materials, and the like.

  The content of the N-substituted cyclic imide unit in the polyolefin resin (A) is preferably 0.1 to 30% by mass, more preferably 0.2 to 25% by mass, and 0.3 to 20% by mass. % Is more preferable, and 0.5 to 15% by mass is particularly preferable. When the content of the N-substituted cyclic imide unit is less than 0.1% by mass, the polyolefin resin (A) is difficult to be dispersed in water, and when it exceeds 30% by mass, the resulting coating film has water resistance and The solvent resistance tends to decrease.

The N-substituent in the N-substituted cyclic imide unit can be arbitrarily used as long as it contains a primary and / or secondary amino group. Among these, a substituent represented by the following general formula (I) is preferable from the viewpoint of dispersibility.
_{-C n H 2n-m + 1} (NRR) m (I)
In the formula, n and m represent natural numbers of 1 to 10, R is an arbitrary atomic group, and one or more of all R in the N-substituent is H.
When n is 11 or more, the polyolefin resin (A) may be difficult to process into an aqueous dispersion due to too many hydrophobic components. When m is 11 or more, the polyolefin resin (A) ), The resulting coating film may have poor water resistance.
Examples of R other than H include an alkyl group, a phenyl group, and an alkenyl group, and an alkyl group is preferable. These may have an amino group, an amide group, a hydroxy group, a carbonyl group, an ether bond or the like in the side chain or the chain.

Specific examples of the N-substituent represented by the general formula (I) include aminoethyl group, aminopropyl group, aminobutyl group, aminopentyl group, N-methylaminoethyl group, N-ethylaminoethyl group, Monoaminoalkyl groups such as N-propylaminoethyl group, polyaminoaminoalkyl groups such as diaminopropyl group, N-methyl-N ′, N′-ethylpropyldiaminopropyl group and triaminopropyl group, aminophenylbutyl group Aromatic alkyl groups such as those containing an amino group on the carbon chain, N- (aminopropyl) aminomethyl group, N-ethylaminomethyl group, (N ′, N′-dimethylaminoethyl) aminomethyl Group, N-ethylamino-2-aminoethyl group, etc., in which an amino group is contained in the carbon chain, and the substituent structure described above May be those the sexual body, it may be used a plurality of these.
Among these, from the viewpoint of dispersibility, an aminoethyl group, aminopropyl group, N-methylaminoethyl group, N-ethylaminoethyl group, and N- (aminopropyl) aminomethyl group are preferable, and an aminopropyl group is most preferable.

  Examples of the compound giving an N-substituted cyclic imide unit include an unsaturated carboxylic acid anhydride and a primary amino compound having a substituent of the general formula (I).

  Specific examples of the unsaturated carboxylic acid anhydride include maleic anhydride, itaconic anhydride and the like, and maleic anhydride is preferable because it is easily copolymerized with the olefinic hydrocarbon unit.

  The polyolefin resin (A) in the present invention may have other monomer units as components in addition to the olefinic hydrocarbon units and N-substituted cyclic imide units.

  Other monomer units include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid and crotonic acid and their anhydrides; methyl (meth) acrylate, ethyl (meth) acrylate, ( (Meth) acrylic acid esters such as propyl (meth) acrylate and butyl (meth) acrylate; maleic acid esters such as dimethyl maleate, diethyl maleate and dibutyl maleate; vinyl such as vinyl formate, vinyl acetate and vinyl propionate Examples thereof include monomer units such as vinyl alcohol obtained by saponifying esters and vinyl esters with basic compounds. In addition, (meth) acrylic acid ester represents acrylic acid ester or methacrylic acid ester.

Especially, it is preferable that the polyolefin resin (A) in this invention contains (meth) acrylic acid ester. When the polyolefin resin (A) contains a (meth) acrylic acid ester, the obtained coating film is further improved in adhesion and adhesiveness.
The content of the (meth) acrylic acid ester unit in the polyolefin resin (A) is preferably 0.1 to 25% by mass, more preferably 0.1 to 20% by mass, and 1 to 15% by mass. More preferably. When the content of the (meth) acrylic acid ester unit exceeds 25% by mass, the strength of the resulting coating film tends to be reduced. On the other hand, when the content is less than 0.1% by mass, the above effect is obtained. It becomes difficult to obtain.

  The mass average molecular weight of the polyolefin resin (A) is preferably 5,000 to 500,000, more preferably 10,000 to 200,000, still more preferably 15,000 to 100,000, and particularly preferably 20,000 to 80,000. When the polyolefin resin (A) has a mass average molecular weight of less than 5,000, the resulting coating film tends to have poor adhesion, adhesion, and solvent resistance. Further, when the mass average molecular weight of the polyolefin resin (A) exceeds 500,000, aqueous dispersion tends to be difficult.

In general, a polyolefin resin is hardly soluble in a solvent, and thus molecular weight measurement may be difficult. In such a case, the melt flow rate value indicating the fluidity of the molten resin is used as a measure of the molecular weight.
The melt flow rate value (in accordance with JIS K7210: 1999) of the polyolefin resin (A) in the present invention is preferably 0.1 to 2000 g / 10 minutes, more preferably 0.5 to 1000 g / 10 minutes. It is more preferable that it is 1-500 g / 10min, and it is especially preferable that it is 2-200g / 10min. When the melt flow rate value of the polyolefin resin (A) exceeds 2000 g / 10 min, the resulting coating film tends to have poor adhesion, adhesion and solvent resistance. Further, when the polyolefin resin (A) has a melt flow rate value of less than 0.1 g / 10 min, aqueous dispersion tends to be difficult.

  Since the polyolefin resin (A) in the present invention has excellent water dispersibility, it need not be chlorinated for the purpose of improving solubility and water dispersibility, and should not be halogenated from the viewpoint of environmental conservation. Is preferred.

<Method for producing polyolefin resin (A)>
Next, the manufacturing method of polyolefin resin (A) is demonstrated.
In the production method of the polyolefin resin (A) in the present invention, (1) an unsaturated carboxylic acid anhydride and a primary amine having a substituent represented by the general formula (I) are subjected to an imidization reaction. A method in which a substituted cyclic imide is prepared in advance, and this is copolymerized with an olefinic hydrocarbon and, if necessary, an unsaturated carboxylic acid or other monomer, (2) an N-substituted cyclic imide prepared in advance A method of grafting to a resin or an olefin copolymer, (3) a copolymer comprising an olefinic hydrocarbon unit and an unsaturated carboxylic anhydride unit (hereinafter referred to as an unsaturated carboxylic anhydride modified polyolefin resin (P)) ) And a primary amino compound having a substituent represented by the general formula (I) (hereinafter referred to as amino compound (Q)) to react and imidize.
Among them, the method (3) allows the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) to be obtained from the market at a low cost, and also allows an imidization reaction without using a special apparatus. , Because it can be suitably processed into an aqueous dispersion.

Hereinafter, the method (3) will be described in detail.
In the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) used in the method (3), the type of olefinic hydrocarbon units and the content of the unsaturated carboxylic acid anhydride units constituting the resin are the polyolefin resin ( Any material satisfying the configuration A) may be used. The unsaturated carboxylic acid anhydride-modified polyolefin resin may have other monomer units in addition to the olefinic hydrocarbon unit and unsaturated carboxylic acid anhydride unit, and the physical properties such as molecular weight of the polyolefin resin (A) If it is satisfactory.

  The state of copolymerization of the unsaturated carboxylic anhydride-modified polyolefin resin (P) is not particularly limited, and examples thereof include random copolymerization, block copolymerization, and graft copolymerization (graft modification).

  As a polymerization method of the unsaturated carboxylic anhydride-modified polyolefin resin (P), a known method can be adopted. For example, a high-pressure radical polymerization method in which polymerization is performed under conditions of a temperature of 100 to 300 ° C. and a pressure of 50 to 400 MPa together with a polymerization initiator such as oxygen, an organic peroxide, or a diazo compound, or an unsaturated carboxylic acid in a polyolefin resin or a polyolefin copolymer. The method of grafting an acid anhydride is mentioned. Among these, the high-pressure radical polymerization method is more preferable because the monomer unit content of the copolymer can be easily designed.

Specific examples of the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) include ethylene-maleic anhydride copolymer, propylene-maleic anhydride copolymer, ethylene- (meth) acrylate methyl-maleic anhydride ternary. Copolymer, Ethylene-ethyl (meth) acrylate-maleic anhydride terpolymer, Ethylene-propyl (meth) acrylate-maleic anhydride, ethylene-butyl (meth) acrylate-anhydrous Ethylene- (meth) acrylic ester-maleic anhydride terpolymer such as maleic acid terpolymer, propylene-butene-maleic anhydride copolymer, propylene-butene-ethylene-maleic anhydride copolymer Etc.
Among these, since the coating film obtained from the aqueous dispersion containing the polyolefin resin (A) after imidation is improved in adhesion and adhesion to the substrate, unsaturated carboxylic anhydride modified polyolefin Resin (P) is ethylene- (meth) acrylate methyl-maleic anhydride terpolymer, ethylene- (meth) ethyl acrylate-maleic anhydride terpolymer, ethylene- (meth) acrylate propyl. -Ethylene- (meth) acrylic ester-maleic anhydride terpolymer such as maleic anhydride terpolymer and ethylene-butyl (meth) acrylate-maleic anhydride terpolymer is preferred.

  These maleic anhydride-modified polyolefin resins are Abonda's “Bondaine”, “Rotada”, “Olevac”, Nippon Polyethylene “Lex Pearl ET”, “Adtex”, NOF “MODIPA”, Sanyo Chemical "Umex" manufactured by Mitsui Chemicals, "Admer" manufactured by Mitsui Chemicals, and "Auroren" manufactured by Nippon Paper Chemicals Co., Ltd. are available.

In the production method of the above (3), the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and the amino compound (Q) represented by the following general formula (II) are subjected to an imidization reaction to produce a polyolefin. Resin (A) is obtained. The amino compound (Q) represented by the following general formula (II) is a primary amine having a substituent represented by the general formula (I).
_{H 2 N-C n H 2n} -m + 1 (NRR) m (II)
In the formula, n and m represent natural numbers of 1 to 10, R is an arbitrary atomic group, and one or more of all R in the amino compound (Q) is H.

  Specific examples of the amino compound (Q) include polyethyleneamines such as diethylenetriamine and triethylenetetramine, and alkylpolyamines such as ethylenediamine and propanediamine.

Next, the imidization reaction will be described.
The above-mentioned unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and amino compound (Q) are mixed and heated to cause an imidization reaction to produce a polyolefin resin (A). That is, the primary amino group in the molecule of the amino compound (Q) is represented by the formula (I) by performing an imidization reaction with the unsaturated carboxylic acid anhydride unit of the unsaturated carboxylic acid anhydride-modified polyolefin resin. N-substituted cyclic imide having a substituent is produced.
At this time, the primary and / or secondary amino group other than the primary amino group of the amino compound (Q) that reacts with the unsaturated carboxylic acid anhydride unit is preferably protected with an appropriate protecting group. Specific examples of the protecting group include carbamate protecting groups, amide protecting groups, imide protecting groups, sulfonamide protecting groups and the like. As a protection method, a known method can be used.

The reaction temperature for imidation is preferably 50 to 300 ° C, more preferably 70 to 250 ° C, further preferably 90 to 200 ° C, and particularly preferably 100 to 170 ° C. If the reaction temperature is less than 50 ° C, the reaction rate may be too slow. On the other hand, temperatures exceeding 300 ° C. are not required for the imidization reaction and may cause coloration.
In the imidation reaction, it is preferable to mix the two by a method such as stirring. The time required for the imidation reaction is not particularly limited, and for example, 30 seconds to 1 hour is preferable, and 1 to 45 minutes is more preferable. In addition, since the imidation reaction has high reactivity, it is not usually necessary to add a catalyst for promoting the reaction.

  The addition amount of the amino compound (Q) in the imidation reaction may be in the range of about 0.6 to 10 equivalents relative to the unsaturated carboxylic acid anhydride unit in the unsaturated carboxylic acid anhydride modified polyolefin resin (P). That's fine. From the viewpoint of the reaction rate described later, 0.6 to 5 times equivalent mol is preferable, 0.7 to 4 times equivalent mol is more preferable, 0.8 to 3 times equivalent mol is further preferable, and 0.9 to 2 times equivalent mol is more preferable. Is most preferred.

  For the polyolefin resin (A), there is no problem even if a small amount of unsaturated carboxylic acid anhydride units not subjected to imidization reaction remain as a constituent component. For the purpose of adjusting the pH of the aqueous dispersion, etc., An unreacted unsaturated carboxylic acid anhydride acid unit may remain within a range not impairing the effects of the invention.

  The reaction rate from the unsaturated carboxylic acid anhydride unit to the N-substituted cyclic imide can be determined by measuring the acid value after the reaction and before the reaction. The acid value can be measured according to JIS K 0070: 1992. In the present invention, the reaction rate is preferably 60% or more, more preferably 70% or more, further preferably 80% or more, and further preferably 90% or more. When the reaction rate is less than 60%, the resulting polyolefin resin (A) may be difficult to disperse in water.

Next, a specific method for the imidization reaction will be described.
The imidization reaction can be performed by a known apparatus and method. Examples thereof include a method of heating and stirring the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and amino compound (Q) in a reaction vessel, and a method of continuously heating and stirring with an extruder.

As a method of heating and stirring the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and the amino compound (Q) in the reaction vessel, a method using a reaction vessel equipped with a stirring blade and, if necessary, a condenser may be mentioned. It is done.
During the imidation reaction, if the reaction vessel is pressure resistant, it may be sealed, and if the reaction vessel is not pressure resistant, steam generated by heating may be refluxed into the reaction vessel via a condenser. .
Unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and amino compound (Q), which are raw materials, may be put into the reaction vessel all at once before the reaction, or unsaturated carboxylic acid anhydride-modified polyolefin resin in advance. Only (P) may be added, and after heating, the amino compound (Q) may be added and stirred.

  The shape of the stirring blade is not limited. Further, the stirring speed is not limited, and cannot be generally specified depending on the volume of the reaction vessel and the shape of the stirring blade, but usually does not require high-speed rotation exceeding 200 rpm, and is generally 200 rpm or less. . Further, the stirring may be intermittent. In the imidation reaction, the gas in the reaction vessel may be replaced with nitrogen gas in order to suppress oxidation of the polyolefin resin.

  In the imidization reaction, the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and the amino compound (Q) are heated to 50 to 300 ° C. to obtain the unsaturated carboxylic acid anhydride-modified polyolefin resin (P). It is preferable to melt.

Further, when the melt viscosity of the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) is high and the load of the stirrer is large, or when the stirring efficiency is low, a solvent may be added.
The solvent is preferably one that dissolves the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) from the viewpoint of increasing the stirring efficiency, but as compared with the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) like water. It may not be soluble. However, non-volatile solvents, high-boiling solvents, and those reactive with the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and amino compound (Q) are not preferred as the solvent. The boiling point of the solvent is preferably 150 ° C. or lower in order to facilitate the removal of the solvent. Preferable specific examples of the solvent include toluene and xylene.
The amount of the solvent added may be appropriately selected depending on the situation, but if the amount is about 100 parts by mass with respect to 100 parts by mass of the resin, the stirring efficiency can be sufficiently improved.

  After the imidization reaction, it is desirable to provide a step of removing unreacted amino compound and solvent in the reaction vessel. As a method for removing the unreacted amino compound and the solvent, a method in which the inside of the reaction vessel is heated and stirred and the pressure is reduced as necessary, and the generated vapor is distilled out of the reaction vessel through a condenser is preferable. The temperature in the reaction vessel at this time is preferably set higher than the boiling point of the amino compound or the solvent.

  After the imidation reaction, the obtained polyolefin resin (A) is preferably pellets having a resin particle size of 10 mm or less when discharged from the reaction vessel.

When the imidization reaction is performed using an extruder, it is preferable that the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and the amino compound (Q) are continuously heated and stirred with the extruder. The extruder is preferably a twin screw extruder equipped with a hopper and a liquid injection device.
In the method using an extruder, an unsaturated carboxylic acid anhydride-modified polyolefin resin (P) is quantitatively supplied from an hopper to an extruder heated so that the temperature of the resin is 50 to 300 ° C., and further in the middle of the barrel The imidization reaction can be carried out by quantitatively introducing the amino compound (Q) from a liquid injection nozzle provided in the container. The rotational speed of the screw is not limited, and may usually be in the range of 20 to 500 rpm.
Even after the imidization reaction in the extruder, it is desirable to provide a step of removing the unreacted amino compound as in the case of performing the imidation reaction using the above-described reaction vessel. As a method for removing unreacted amino compounds, a method is preferred in which the inside of the extruder is depressurized from a vent provided in the latter half of the barrel of the extruder, and the generated vapor is distilled out of the extruder through a condenser. .

  The polyolefin resin (A) obtained by the above method may be further provided with a step of removing the unreacted amino compound (Q) as necessary. Examples of the method for removing the unreacted amino compound (Q) include a method for heating and drying the obtained polyolefin resin (A), a method for heating and vacuum drying, and a method for extracting.

  When an amino compound (Q) having a primary and / or secondary amino group protected by a protecting group other than the primary amino group that reacts with an unsaturated carboxylic acid anhydride unit is used, an imidization reaction It is preferable to perform deprotection later and before processing into an aqueous dispersion described later. Or you may deprotect simultaneously with the process to an aqueous dispersion. A known method can be used for deprotection.

<Crosslinking agent (B)>
The aqueous dispersion of the present invention contains the polyolefin resin (A) and the crosslinking agent (B).
When the aqueous dispersion contains the crosslinking agent (B), it is possible to impart more excellent performance such as hot water resistance, chemical resistance, and heat resistance to the obtained coating film.
As the crosslinking agent (B), a compound having a plurality of functional groups that react with amino groups in the molecule, a crosslinking agent having self-crosslinking property, a metal complex having a multivalent coordination site, or the like can be used.
Specifically, carboxylic acid compounds, epoxy compounds, isocyanate compounds, urea compounds, carbonyl compounds, carboxylic acid anhydrides, zirconium salt compounds, silane coupling agents, organic peroxides, and the like can be used.
Among these, from the viewpoint of reactivity with an amino group, the crosslinking agent (B) has an acid anhydride group, an epoxy group, an isocyanate group, a blocked isocyanate group, and a carbamide group as functional groups that react with the amino group. Compounds are preferred, and these crosslinking agents may be used in combination.
The content (solid content) of the crosslinking agent (B) is preferably in the range of 0.01 to 300 parts by mass with respect to 100 parts by mass of the solid content of the polyolefin resin (A) in the aqueous dispersion. The range of parts by mass is more preferred, the range of 0.2 to 50 parts by mass is more preferred, and the range of 0.5 to 30 parts by mass is particularly preferred.

<Aqueous dispersion>
Next, the aqueous dispersion of the present invention will be described. The aqueous dispersion of the present invention is obtained by dispersing a polyolefin resin (A) and a crosslinking agent (B) in an aqueous medium.

  The aqueous medium in the present invention refers to water or a mixed liquid of water and an organic solvent. Since the aqueous dispersion of the present invention uses an aqueous medium, the influence on the environment and the safety to workers and the working environment are improved.

  The organic solvent has a solubility in water at 20 ° C. of preferably 50 g / L or more, and more preferably 500 g / L or more. Furthermore, what dissolve | melts with water and arbitrary ratios is especially preferable. By using such an organic solvent, the effect of promoting aqueous dispersion and the effect of reducing the particle diameter can be improved.

  Moreover, it is preferable that the boiling point of an organic solvent is 50-200 degreeC. When the boiling point of the organic solvent is less than 50 ° C., the rate of volatilization during aqueous dispersion increases, and the efficiency of dispersion may not be sufficiently improved. When the boiling point exceeds 200 ° C., it tends to remain in the coating film obtained from the aqueous dispersion, and the water resistance and solvent resistance tend to decrease.

  Specific examples of the organic solvent having a solubility in water at 20 ° C. of 50 g / L or more and a boiling point of 50 to 200 ° C. include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol. , Tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol, cyclohexanol and the like; Ketones such as methyl ethyl ketone, methyl isobutyl ketone, ethyl butyl ketone and cyclohexanone; ethers such as tetrahydrofuran and dioxane; ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, iso-acetate Chill, acetate-sec-butyl, acetate-3-methoxybutyl, methyl propionate, ethyl propionate, diethyl carbonate, esters of dimethyl carbonate, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl Glycol derivatives such as ether, ethylene glycol monobutyl ether, ethylene glycol ethyl ether acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol methyl ether acetate ; The 3-methoxy-3-methylbutanol, 3-methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate, and the like. In addition, you may use these organic solvents in mixture of 2 or more types.

  Among the above, ethanol, n-propanol, isopropanol, n-butanol, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, Dioxane, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and ethylene glycol monobutyl ether are preferable, and ethanol, n-propanol, isopropanol, and tetrahydrofuran are particularly preferable.

  The content of the organic solvent in the aqueous medium is preferably 50% by mass or less, more preferably 1 to 40% by mass, further preferably 2 to 35% by mass, and particularly preferably 3 to 30% by mass. When the content of the organic solvent exceeds 50% by mass, the effect of promoting aqueous dispersion does not change or tends to decrease.

  The organic solvent as described above added in the aqueous dispersion can be removed from the aqueous dispersion after the aqueous dispersion. For example, a part thereof can be removed from the aqueous dispersion by a solvent removal operation called stripping. By such stripping, the content of the organic solvent can be reduced to 0.1% by mass or less as necessary. Even if the content of the organic solvent is 0.1% by mass or less, the performance of the aqueous dispersion is not affected. Examples of the stripping method include a method in which the aqueous dispersion is heated with stirring at normal pressure or reduced pressure to distill off the organic solvent. Moreover, since the resin solid content concentration in the aqueous dispersion is increased by distilling off the aqueous medium, it is possible to adjust the resin solid content concentration to a preferable range described later.

  The aqueous dispersion of the present invention contains an acidic compound, and part or all of the substituents represented by the general formula (I) in the polyolefin resin (A) in the aqueous dispersion are neutralized with the acidic compound. It is preferable that An amino cation is generated in the polyolefin resin (A) by neutralization of the substituent, and the polyolefin resin (A) is finely divided by an electric repulsive force between the amino cations, and aggregation between the fine particles is released. As a result, stability is imparted to the aqueous dispersion, and the aqueous dispersion becomes stable in the acidic region.

That is, in an aqueous medium containing an acidic compound, part or all of the N-substituent in the N-substituted cyclic imide unit in the polyolefin resin (A) is a substituent represented by the following general formula (III). Thus, the polyolefin resin (A) can be dispersed in the aqueous medium.
^{_{-C n H 2n-m + 1}} (N + HRR) m X - (III)
In the formula, n and m represent natural numbers of 1 to 10, R is an arbitrary atomic group, one or more of all R in the substituent is H, and X ⁻ represents an anionic counter ion.

  The content of the acidic compound in the aqueous dispersion is preferably 0.5 to 5 equivalents relative to all amino groups in the substituent represented by the general formula (I) contained in the polyolefin resin (A). .8-3 equivalents are more preferred, and 1-2.5 equivalents are even more preferred. If the content of the acidic compound is less than 0.5 equivalent mole, the aqueous dispersion may not maintain a stable form. If the content exceeds 5 equivalents, the aqueous dispersion may be colored or the coating film may be dried. It may take longer.

The acidic compound is capable of neutralizing the substituent represented by the general formula (I), and preferably has an acid dissociation constant (pK _a ) of −9 to 8 in water, pK _a more preferably those There is -9～7, more preferably those pK _a is -5～6 those pK _a is 0-5 are particularly preferred. When the acid dissociation constant (pK _a ) exceeds 8, the substituents are hardly neutralized, and it tends to be difficult to disperse in water. When the acid dissociation constant is less than −9, the operation for obtaining the aqueous dispersion tends to be difficult.

  Moreover, it is preferable that an acidic compound is volatile, specifically, it is preferable that a boiling point is 20-250 degreeC, it is more preferable that it is 30-200 degreeC, and it is that it is 50-150 degreeC. More preferably, it is 50-120 degreeC. If the acidic compound is non-volatile, the resulting coating film has a tendency for the acidic compound to remain and the adhesion and water resistance to decrease. On the other hand, if the boiling point of the acidic compound is too low, the rate of volatilization during aqueous dispersion increases, and the efficiency of neutralization may not increase.

  Specific examples of the acidic compound include organic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, lactic acid and citric acid; and inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid and nitric acid. These may be used alone or in combination of two or more. Of these, organic acids are preferred because of excellent neutralization of substituents, and formic acid and acetic acid are more preferred.

  Moreover, it is preferable that the aqueous dispersion of the present invention does not substantially contain a nonvolatile aqueous dispersion aid. The non-volatile aqueous dispersion aid remains in the coating film obtained from the aqueous dispersion and plasticizes or hydrophilicizes the coating film. Therefore, film properties such as adhesion to the substrate, water resistance and solvent resistance are deteriorated. Since the aqueous dispersion of the present invention is an aqueous dispersion using the polyolefin resin (A) of the present invention, the aqueous dispersion is excellent in water dispersibility and substantially does not contain a nonvolatile aqueous dispersion aid. It becomes possible.

  Here, “substantially free of non-volatile aqueous dispersion aid” means that the non-volatile aqueous dispersion aid is not actively added to the system, so that 100 parts by mass of the polyolefin resin (A) component It means that the content of the nonvolatile aqueous dispersion aid is less than 0.1 parts by mass. Preferably, the content of the non-volatile aqueous dispersion aid is zero. Nonvolatile means that it does not have a boiling point at normal pressure or has a high boiling point of 300 ° C. or higher at normal pressure.

  In the present invention, the non-volatile aqueous dispersion aid refers to a non-volatile drug or compound added for the purpose of promoting aqueous dispersion or stabilizing the aqueous dispersion in aqueous dispersion. Specific examples include an emulsifier, a compound having a protective colloid effect, a modified wax, a high amino-modified compound, an acid-modified compound having a high acid value, and a water-soluble polymer. Examples of the emulsifier include a cationic emulsifier, an anionic emulsifier, a nonionic emulsifier, and an amphoteric emulsifier. In addition to those generally used for emulsion polymerization, surfactants are also included. For example, anionic emulsifiers include higher alcohol sulfates, higher alkyl sulfonates, higher carboxylates, alkyl benzene sulfonates, polyoxyethylene alkyl sulfate salts, polyoxyethylene alkyl phenyl ether sulfate salts, vinyl sulfosuccinates. Nonionic emulsifiers include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyethylene glycol fatty acid ester, ethylene oxide propylene oxide block copolymer, polyoxyethylene fatty acid amide, ethylene oxide-propylene oxide. Compounds having a polyoxyethylene structure such as copolymers and sorbitan derivatives such as polyoxyethylene sorbitan fatty acid esters Examples of the cationic emulsifier include quaternary ammonium salts such as alkyltrimethylammonium salt and dialkyldimethylammonium salt, and alkylamine salts. Examples of the amphoteric emulsifier include laurylbetaine, lauryldimethylamine oxide, and the like. It is done.

  Compounds having protective colloid action, modified waxes, high amino modified compounds, acid modified compounds with high acid value, water-soluble polymers include polyvinyl alcohol, amino modified polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, modified starch, polyvinyl Pyrrolidone, polyacrylic acid and salts thereof, amino group-containing polyethylene wax, amino group-containing polypropylene wax, amino group-containing polyethylene-propylene wax and the like amino-modified polyolefin waxes having a number average molecular weight of usually 5000 or less and salts thereof, amino groups Examples thereof include water-soluble acrylic copolymers having gelatin, gelatin, gum arabic, and casein, which are generally used as fine particle dispersion stabilizers.

  In the aqueous dispersion of the present invention, various additives can be mixed in order to obtain the performance required depending on the intended use as long as the effect is not impaired. Resins other than the polyolefin resin (A) in the present invention, inorganic fine particles, and the like can be added to the aqueous dispersion of the present invention.

  Resins other than the above-described polyolefin resin (A) (hereinafter may be referred to as other resins) are not particularly limited. Examples of other resins include polyvinyl acetate, polyvinyl alcohol, polyvinyl chloride, acrylic resin, acrylic silicon resin, ethylene-vinyl acetate copolymer, vinyl acetate-acrylic copolymer, ethylene-aminoacrylamide copolymer, and ethylene. -Amino acrylate copolymer, poly vinylidene chloride, ethylene- (meth) acrylic acid copolymer, styrene-maleic acid resin, styrene-aminoalkyl cyclic imide copolymer, styrene-butadiene resin, styrene elastomer, butadiene resin, Acrylonitrile-butadiene resin, poly (meth) acrylonitrile resin, (meth) acrylamide resin, chlorinated polyethylene resin, chlorinated polypropylene resin, polyester resin, modified nylon resin, urethane resin, phenol resin, silicone Resins, epoxy resins, polyethylene imine, and UV curing resins, mention may be made of their aqueous dispersion or an aqueous solution thereof. You may use these in mixture of 2 or more types.

Examples of the inorganic fine particles described above include magnesium oxide, zinc oxide, tin oxide, titanium oxide, calcium carbonate, silica, barium sulfate, calcium silicate, zeolite, kaolinite, halloysite, magnesium carbonate, calcium sulfate, mica, talc, pseudo Examples thereof include fine particles of inorganic compounds such as boehmite, alumina, aluminum silicate, calcium silicate, magnesium silicate, zirconium oxide, zirconium hydroxide, cerium oxide, lanthanum oxide, and yttrium oxide. You may use these in mixture of 2 or more types.
The average particle diameter of the inorganic fine particles is preferably from 0.0005 to 100 μm, more preferably from 0.005 to 10 μm, from the viewpoint of the stability of the aqueous dispersion.

  In addition, various agents such as leveling agents, antifoaming agents, anti-waxing agents, pigment dispersants, UV absorbers, catalysts, photocatalysts, UV curing agents, antistatic agents, pigments or dyes, carbon black, carbon nanotubes as necessary Etc. may be added. It is also possible to add organic or inorganic compounds other than those described above to the aqueous dispersion as long as the stability of the aqueous dispersion is not impaired.

  Additives such as other resins, inorganic particles, various drugs, pigments, and dyes may be used alone or in combination of two or more.

  The number average particle diameter of the polyolefin resin (A) in the aqueous dispersion of the present invention is preferably 1000 nm or less, more preferably 750 nm or less, more preferably 500 nm or less, and 300 nm or less. Is most preferred. When the number average particle diameter exceeds 1000 nm, the storage stability of the aqueous dispersion is lowered, or the film forming property when applied is inferior, so that the coating film tends to be non-uniform.

  Furthermore, the volume average particle diameter of the polyolefin copolymer in the aqueous dispersion is preferably 1000 nm or less from the viewpoint of excellent storage stability of the aqueous dispersion and film forming properties when the aqueous dispersion is applied. It is preferably 750 nm or less, more preferably 500 nm or less, and particularly preferably 300 nm or less.

  The particle size distribution degree (volume average particle size / number average particle size) is preferably 1 to 3, from the viewpoint of storage stability of the aqueous dispersion and wettability when the aqueous dispersion is applied. 5 is more preferable, and 1-2 is more preferable. When the degree of distribution of the particle diameter exceeds 3, the storage stability of the aqueous dispersion may be lowered. On the other hand, when the particle size distribution is less than 1, wettability may be reduced when the aqueous dispersion is applied.

  The aqueous dispersion of the present invention is stable in the acidic region, and the pH of the aqueous dispersion is preferably 2 to 6, and more preferably 2.5 to 4.5. The stability of the aqueous dispersion in the present invention refers to a property without phase separation in which agglomeration or precipitation of dispersed resin particles is not recognized in appearance and maintains a uniformly dispersed state.

  The solid content concentration of the aqueous dispersion of the present invention can be appropriately selected according to the purpose of use and the storage method. In any case, the solid concentration is preferably 2 to 60% by mass of the aqueous dispersion, more preferably 5 to 50% by mass, and still more preferably 10 to 45% by mass. By setting the solid content concentration in such a range, the thickness when the aqueous dispersion is applied can be favorably maintained.

  The aqueous dispersion of the present invention has a viscosity measured with a B-type viscometer at 20 ° C., preferably 100,000 mPa · s or less, more preferably 10,000 mPa · s or less, still more preferably 5000 mPa · s or less, and 1000 mPa · s. The following is particularly preferable, and 500 mPa · s or less is most preferable. When the viscosity of the aqueous dispersion exceeds 100,000 mPa · s, it becomes difficult to apply the aqueous dispersion.

The coating film obtained from the aqueous dispersion of the present invention has excellent hot water resistance, chemical resistance, and heat resistance because the polyolefin resin (A) has a cyclic imide structure and is crosslinked.
Moreover, the aqueous dispersion of the present invention is excellent in film-forming properties (coating film-forming properties), and can form a transparent coating film by being subjected to various drying processes after being applied to various substrates. it can. Furthermore, the formed coating film has excellent adhesion to various substrates such as metal, glass, plastic moldings, films, fibers, non-woven fabrics, wood, synthetic paper, paper, and adhesives. Can be used as
In addition to the adhesive, the aqueous dispersion of the present invention includes a primer, an anchor coating agent, a surface modifier, a surface protective agent, a fiber modifier, an electrodeposition paint, a rust preventive paint, a building material paint, an ink receiving layer, It can be used in various applications such as ink binders, battery binders, antistatic agents, lubricants, wetting agents, release paints, antifogging paints, waterproof paints, water repellent paints, and antibacterial paints.

<Method for producing aqueous dispersion>
Next, the manufacturing method of the aqueous dispersion of this invention is demonstrated.
Examples of the method for producing the aqueous dispersion of the present invention include a method of mixing the aqueous dispersion of the polyolefin resin (A) and the crosslinking agent (B).
The aqueous dispersion of the polyolefin resin (A) can be prepared, for example, by stirring the polyolefin resin (A), the aqueous medium, and the acidic compound at 80 to 250 ° C. in a sealable container.

The container which can be sealed is equipped with a tank into which a liquid can be charged, and may be any one that can moderately stir the polyolefin resin (A), the aqueous medium, or the acidic compound charged into the tank. An emulsifier can be used, and it is more preferable that it is pressure resistant.
While the polyolefin resin (A), the aqueous medium and the acidic compound are put into the container, the temperature in the tank is kept at 80 to 250 ° C., preferably 90 to 200 ° C., more preferably 100 to 190 ° C. By continuing the stirring for ˜180 minutes, the polyolefin resin (A) can be sufficiently dispersed. When the temperature in the tank is less than 80 ° C., the dispersion effect of the polyolefin resin (A) is low, and even if the temperature exceeds 250 ° C., the effect of aqueous dispersion is not further improved.
The stirring method and the rotation speed of stirring are not particularly limited. In the present invention, high-speed stirring (for example, 1000 rpm or more) is not essential because sufficient aqueous formation can be achieved even with low-speed stirring that allows the polyolefin resin (A) to float in an aqueous medium. For this reason, the aqueous dispersion can be produced with a simple apparatus.
Then, for example, an aqueous dispersion can be obtained by cooling to 40 ° C. or lower under stirring.
According to the above method, the polyolefin resin (A) is dispersed in the aqueous medium without substantially adding the non-volatile aqueous additive, and a stable aqueous dispersion is prepared.

  The polyolefin resin (A) in the present invention is very good in aqueous dispersion, and little or no undispersed resin remains in the aqueous medium. However, a filtration step may be provided when the aqueous dispersion is dispensed in order to remove foreign substances in the container and a small amount of undispersed resin. The filtration method is not limited, and examples thereof include a method of pressure filtration with a stainless steel filter or the like. By providing such a filtration step, it is possible to remove even if foreign matter or undispersed resin is present, and the aqueous dispersion can be used without problems in the subsequent steps.

  Moreover, the aqueous dispersion yield can be determined by measuring the amount of undispersed resin remaining on the filter after filtration. The aqueous dispersion yield is preferably 50% or more, more preferably 70% or more, still more preferably 85% or more, particularly preferably 95% or more, and most preferably 100% from the viewpoint of maintaining good productivity. preferable.

<Formation of coating film>
The aqueous dispersion of the present invention is excellent in film forming properties. Therefore, it is uniform on the surface of various substrates by known film formation methods such as gravure roll coating, reverse roll coating, wire bar coating, lip coating, air knife coating, curtain flow coating, spray coating, dip coating, and brushing. Can be coated. Then, after setting as near room temperature as necessary, it is subjected to heat treatment for drying or drying and baking to form a laminate by bringing a uniform coating (resin layer) into close contact with the substrate surface. Can do.

  As an apparatus for the heat treatment, a normal hot air circulation type oven, an infrared heater, or the like can be used. In addition, the heating temperature and the heating time are appropriately selected depending on the characteristics of the base material, the type of additive, the blending amount, and the like. Is more preferable, 80 to 180 ° C. is particularly preferable, and the heating time is preferably 1 second to 20 minutes, more preferably 5 seconds to 15 minutes, and particularly preferably 5 seconds to 10 minutes.

Moreover, the thickness of a coating film is suitably selected by the use, and 0.01-1000 micrometers is preferable among these, 0.1-100 micrometers is more preferable, 0.1-50 micrometers is especially preferable. Moreover, although the thickness of a coating film may be non-uniform depending on a use, generally it is preferable that it is uniform.
In order to adjust the thickness of the coating film, in addition to appropriately selecting the equipment used for coating and its use conditions, use an aqueous dispersion with a solid content concentration suitable for the desired coating film thickness. Is preferred. The solid content concentration of the aqueous dispersion can be adjusted by the preparation composition at the time of preparation of the aqueous dispersion, and the obtained aqueous dispersion may be appropriately diluted or concentrated.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.
Various characteristics were measured or evaluated by the following methods.

1. Resin composition
^It calculated | required using the <1> H-NMR analyzer (The JEOL company make, ECA500, 500MHz). Tetrachloroethane (d ₂ ) was used as a solvent and measurement was performed at 120 ° C.

2. Reaction rate The acid value of the unsaturated carboxylic acid anhydride-modified polyolefin resin (P) and the acid value of the polyolefin resin (A) obtained by reacting with the amino compound (Q) are described in JIS K 0070: 1992, respectively. The imidation reaction rate was calculated from the following formula.
Reaction rate (%) = (acid value of resin (P) −acid value of resin (A)) / acid value of resin (P) × 100

3. The particle diameter of the modified polyolefin resin was determined using a Microtrac particle size distribution meter (UPA150, MODEL No. 9340, dynamic light scattering method, manufactured by Nikkiso Co., Ltd.). The refractive index of the resin used for particle diameter calculation was 1.50.

4). Weight average molecular weight Using a GPC apparatus (manufactured by Tosoh Corporation, HLC-8020GPC, column: TSK-GEL, eluent: orthodichlorobenzene), the weight average molecular weight was measured at 40 ° C. and calculated from TSK standard polystyrene conversion.

5. Melt flow rate value (MFR)
It was measured by the method described in JIS K7210: 1999.

6). Melting point 10 mg of maleic anhydride-modified polyolefin resin was used as a sample, and measured using a DSC (Differential Scanning Calorimetry) apparatus (DSC7 manufactured by PerkinElmer Co., Ltd.) at a temperature rising rate of 10 ° C./min.

7). Adhesive strength A biaxially stretched polyester film (PET, manufactured by Unitika Co., Ltd.) is used as a base material, an aqueous dispersion is applied to the corona-treated surface, and then dried at 100 ° C. for 30 seconds. An adhesive layer made of a film was formed. Subsequently, a polyethylene resin (Novatec LC600A, manufactured by Nippon Polyethylene Co., Ltd.) as a sealant resin was melt-extruded at 280 ° C. on the surface of the adhesive layer using a laminator equipped with an extruder, and a sealant layer having a thickness of 30 μm was provided. A laminated film was obtained.
The obtained laminate film was cut out with a width of 15 mm, and the peel strength was measured by using a tensile tester (manufactured by Intesco, precision universal material tester type 2020) at room temperature, a tensile speed of 200 mm / min, and T-type peeling. The measurement was performed 5 times, and the average value was obtained.

8). Hot water resistant glass substrate (standard test piece, float plate glass, thickness 1.5 mm) was used as the base material, and the aqueous dispersion was applied to the glass plate with a Mayer bar, then dried at 90 ° C. for 2 minutes, A laminate having a thickness of 10 μm was obtained.
The obtained laminate was immersed in hot water at 98 ° C. for 24 hours. The taken-out laminate was left to stand for 24 hours with a dryer at 60 ° C. and dried, then the state of the laminate was visually confirmed, and hot water resistance was evaluated according to the following criteria.
A: No change was observed in the coating film, and the transparent state was maintained.
(Triangle | delta): Whitening, swelling, partial peeling, etc. were seen by the coating film.
X: The coating film was completely peeled off.

9. Chemical resistance A laminate was prepared by the method described in “8. The obtained laminate was immersed in toluene and allowed to stand at room temperature for 24 hours, and then the taken laminate was allowed to stand for 24 hours in a dryer at 60 ° C. and dried, and then a thickness meter (manufactured by HEIDENHAIN, MT12B) Was used to measure the thickness. The remaining rate of the coating film was calculated by the following formula.
[(Film thickness after test, μm) / (film thickness before test (10 μm))] × 100

10. Uniformity of coating film An aqueous dispersion is applied to the glass plate described in "8. Hot water resistance" above with a Mayer bar, and then dried at 90 ° C for 2 minutes, and a laminate having a coating film thickness of 0.3 µm Got the body. The state of the obtained laminate was visually confirmed, and the uniformity was evaluated according to the following criteria.
○: No foreign matter is observed in the coating film, and it is completely transparent.
Δ: A small amount of foreign matter is present in the coating film, and the coating film is slightly turbid.
X: A large amount of foreign matter is present in the coating film, and the coating film is cloudy.

The raw materials for the aqueous polyolefin resin dispersion are shown below.
1. Unsaturated carboxylic acid anhydride modified polyolefin resin (P)
P1 to P6:
Produced by high-pressure radical polymerization of ethylene, ethyl acrylate, and maleic anhydride according to the methods described in British Patent No. 2911745, US Pat. No. 4,617,366 and US Pat. No. 4,644,044.
P7:
It was produced by grafting maleic anhydride onto a propylene-butene-ethylene terpolymer according to the method described in the production example of WO2004 / 104090.
P8:
It was produced by grafting maleic anhydride onto polypropylene in the same manner as P7.
Table 1 shows the compositions and properties of the maleic anhydride-modified polyolefin resins (P1) to (P8).

2. Amino compound (Q)
Q1 (N- (2-aminoethyl) maleimide):
Ethylenediamine 60 g, maleic anhydride 117.6 g, and toluene 200 ml were added to a 500 ml round bottom flask equipped with a Dean-Stark apparatus, and nitrogen substitution was performed. The round bottom flask was heated to 125 ° C. in an oil bath and refluxed for 1 hour, and then the pressure was reduced to remove toluene and unreacted ethylenediamine. The distillation residue was purified by silica gel column chromatography to obtain N- (2-aminoethyl) maleimide.

Q2 (N, N-di-tert-butoxycarbonyl-3-aminopropylamine):
To a 500-ml round bottom flask equipped with a Dean-Stark apparatus, 89 g of 1,3-propanediamine, 117.6 g of maleic anhydride, and 200 ml of toluene were added, and nitrogen substitution was performed. The round bottom flask was heated to 125 ° C. in an oil bath and refluxed for 1 hour, and then the pressure was reduced to remove toluene and unreacted 1,3-propanediamine. The distillation residue was purified by silica gel column chromatography to obtain N- (3-aminopropyl) maleimide.
To a round bottom flask having a volume of 500 ml, 154 g of N- (3-aminopropyl) maleimide and 100 ml of dichloromethane were added, and 218 g of di-tert-butyl dicarbonate was added over 30 minutes while stirring at room temperature. After stirring for 1 hour, the pressure was reduced to remove dichloromethane. The distillation residue was purified by silica gel column chromatography to obtain N- (3-N ′, N′-di-tert-butoxycarbonylaminopropyl) maleimide.
To a round bottom flask having a volume of 500 ml, add 50 g of N- (3-N ′, N′-di-tert-butoxycarbonyl-3-aminopropyl) maleimide, 20.4 ml of hydrazine hydrate, and 400 ml of ethanol at 65 ° C. The mixture was heated and stirred for 4 hours. Thereafter, the pressure was reduced, ethanol was removed, and the distillation residue was purified by silica gel column chromatography to obtain N, N-di-tert-butoxycarbonyl-3-aminopropylamine.

Q3 (N ′, N′-di-tert-butoxycarbonylaminoethyl-N-tert-butoxycarbonyl-2-aminoethylamine):
To a 500-ml round bottom flask equipped with a Dean-Stark apparatus, 103 g of diethylenetriamine, 117.6 g of maleic anhydride, and 200 ml of toluene were added to perform nitrogen substitution. The round bottom flask was heated to 125 ° C. in an oil bath and refluxed for 1 hour, and then the pressure was reduced to remove toluene and unreacted diethylenetriamine. The distillation residue was purified by silica gel column chromatography to obtain N-((N′-aminoethyl) -2-aminoethyl) maleimide.
To a round bottom flask with a capacity of 500 ml, add 50 g of N-((N′-aminoethyl) -2-aminoethyl) maleimide and 100 ml of dichloromethane, and stir at room temperature with 89 g of di-tert-butyl dicarbonate for 30 minutes. Added over time. After stirring for 1 hour, the pressure was reduced to remove dichloromethane. The distillation residue was purified by silica gel column chromatography to obtain N- (N ″, N ″ -di-tert-butoxycarbonylaminoethyl-N′-tert-butoxycarbonyl-2-aminoethyl) maleimide.
In a 500 ml round bottom flask, 50 g of N- (N ″, N ″ -di-tert-butoxycarbonylaminoethyl-N′-tert-butoxycarbonyl-2-aminoethyl) maleimide, 30 ml of hydrazine hydrate, 400 ml of ethanol. And heated and stirred at 65 ° C. for 4 hours. Then, the pressure was reduced to remove ethanol, and the distillation residue was purified by silica gel column chromatography to obtain N ', N'-di-tert-butoxycarbonylaminoethyl-N-tert-butoxycarbonyl-2-aminoethylamine.

As Q4, n-propylamine was used.
As Q5, N, N-dimethyl-3-aminopropylamine was used.

The following were used for the crosslinking agent (B).
B1: Hexamethylene-1,6-diisocyanate B2: Propylene glycol diglycidyl ether B3: 3,3'-4,4'-benzophenone tetracarboxylic dianhydride B4: Hydroxyethylurea

Example 1
In a 1 liter separable flask equipped with a thermometer, stirrer, liquid injector, and Dimroth, 250 g of maleic anhydride polyolefin resin (P1) and 500 g of toluene were charged, and the stirrer was rotated at 100 rpm. It put into the 125 degreeC oil bath. After toluene was refluxed and it was confirmed that the resin (P1) was completely dissolved, 1.05 equivalent of the amino compound (Q1) was added to the number of moles of maleic anhydride units of the resin (P1). Then, it hold | maintained at 125 degreeC for 1 hour, and imidation reaction was performed.
After reprecipitation of the reaction solution with 500 ml of acetone, 30 ml of hydrazine hydrate and 400 ml of ethanol were added to the obtained resin, and the mixture was stirred at 65 ° C. for 4 hours to remove the protecting group of the amino group. Thereafter, vacuum drying was performed for 16 hours to obtain a polyolefin resin containing an N-substituted cyclic imide unit and the N-substituent being a 2-aminoethyl group.
In a sealable 1-liter pressure-resistant glass container equipped with a stirrer and a heater, 140 g of the polyolefin resin obtained by the above method, 4.0 equivalents of formic acid as an acidic compound, based on the total amount of amino groups in the polyolefin resin, organic As a solvent, 245 g of 2-propanol and distilled water were added to make the total amount 700 g. Next, the container was sealed, and stirring and mixing were performed with the rotation speed of the stirring blade set to 200 rpm. Turn on the power of the heater, bring the temperature inside the container to 130 ° C, and further stir for 120 minutes, then naturally cool to 40 ° C, filter the contents in the container with a 300 mesh stainless steel filter, and remove the aqueous dispersion of polyolefin resin. Obtained.
The aqueous dispersion (E1) was obtained by adding the crosslinking agent (B1) to the polyolefin resin aqueous dispersion in an amount of 10 parts by mass with respect to 100 parts by mass of the polyolefin resin.

Examples 2-8
Aqueous dispersions (E2) to (E8) were obtained in the same manner as in Example 1, except that the maleic anhydride-modified polyolefin resin (P1) was changed to the resin described in Table 2.

Example 9
A 1-liter separable flask equipped with a thermometer, stirrer, liquid injector, and Dimroth was charged with 250 g of maleic anhydride-modified polyolefin resin (P2) and 500 g of toluene, and the stirrer was rotated at 100 rpm. It put into the 125 degreeC oil bath. After toluene was refluxed and it was confirmed that the resin (P2) was completely dissolved, 1.05 equivalent of the amino compound (Q2) was added to the number of moles of maleic anhydride units of the resin (P2). Then, the imidation reaction was performed by holding at 125 ° C. for 1 hour.
The reaction solution was reprecipitated with 500 ml of acetone, and then vacuum-dried under reduced pressure for 16 hours. The N-substituted cyclic imide unit was contained and the N-substituent was N, N-di-tert-butoxycarbonyl-3-amino. A polyolefin resin having a propyl group was obtained.
Thereafter, a polyolefin in which the N, N-di-tert-butoxycarbonyl-3-aminopropyl group of the N-substituent was converted to a 3-aminopropyl group by performing the same aqueous dispersion operation as in Example 1. An aqueous dispersion containing a resin was obtained, and then a crosslinking agent was added to obtain an aqueous dispersion (E9).

Example 10
The N-substituted cyclic imide unit is contained in the same manner as in Example 9 except that the amino compound (Q2) is changed to (Q3), and the N-substituent is an N-aminoethyl-2-aminoethyl group. An aqueous dispersion (E10) containing a polyolefin resin was obtained.

Examples 11-13
Aqueous dispersions (E11) to (E13) were obtained in the same manner as in Example 2 except that the crosslinking agent (B1) was changed to that shown in Table 2.

Comparative Example 1
An aqueous dispersion (E14) was obtained in the same manner as in Example 9 except that the crosslinking agent was not added.

Comparative Example 2
Except that the amino compound (Q1) was changed to n-propylamine (Q4), the same method as in Example 2 was performed. As a result, the polyolefin resin was present in the container in a swollen state. Couldn't get.

Comparative Example 3
The N-substituent was N, N-dimethyl-3-aminopropyl in the same manner as in Example 9, except that the amino compound (Q2) was changed to N, N-dimethyl-3-aminopropylamine (Q5). An aqueous dispersion (E15) containing a polyolefin resin as a group was obtained.

Comparative Example 4
Using an aqueous solution of polyallylamine (manufactured by Nittobo Co., Ltd., PAA-25), 10 parts by mass of the crosslinking agent (B1) was added to 100 parts by mass of the solid component of polyallylamine to obtain an aqueous dispersion (E16).

  About the aqueous dispersion obtained by said method, the adhesive strength, hot water resistance, chemical resistance, and uniformity of the obtained coating film were evaluated. The results are shown in Table 2.

As is apparent from Table 2, the aqueous dispersions of Examples 1 to 13 contain a polyolefin resin (A) containing a primary and / or secondary amino group in the N-substituent and a crosslinking agent (B). The coating film obtained showed excellent performance in all of adhesiveness, hot water resistance, and chemical resistance.
On the other hand, since the aqueous dispersion of Comparative Example 1 did not have a crosslinking agent, the obtained coating film was inferior in hot water resistance and chemical resistance.
In Comparative Example 2, since the polyolefin resin did not contain an amino group in the N-substituent, an aqueous dispersion could not be obtained.
In the aqueous dispersion of Comparative Example 3, since the polyolefin resin contains neither a primary amino group nor a secondary amino group in the N-substituent, even if it contains a crosslinking agent, the hot water resistance and chemical resistance of the coating film The effect of improving was not obtained.
In Comparative Example 4, since the polyolefin resin did not contain an N-substituted cyclic imide unit, the obtained coating film was inferior in hot water resistance, chemical resistance, and uniformity.

Claims (7)

  An aqueous dispersion comprising a polyolefin resin (A) and a crosslinking agent (B) dispersed in an aqueous medium, wherein the polyolefin resin (A) contains an N-substituted cyclic imide unit, A polyolefin resin aqueous dispersion, wherein the group contains primary and / or secondary amino groups. 2. The polyolefin resin aqueous dispersion according to claim 1, wherein the N-substituent is a substituent represented by the following general formula (I).
_{-C n H 2n-m + 1} (NRR) m (I)
(In the formula, n and m represent natural numbers of 1 to 10, R is an arbitrary atomic group, and one or more of all R in the N-substituent is H.)   The polyolefin resin aqueous dispersion according to claim 1 or 2, wherein the content of the N-substituted cyclic imide unit in the polyolefin resin (A) is 0.1 to 30% by mass.   The polyolefin resin aqueous dispersion according to any one of claims 1 to 3, wherein the polyolefin resin further contains a (meth) acrylic acid ester unit.   The polyolefin resin aqueous dispersion according to any one of claims 1 to 4, wherein the crosslinking agent (B) contains a functional group that reacts with an amino group.   6. The aqueous polyolefin resin according to claim 5, wherein the functional group that reacts with an amino group is at least one selected from the group consisting of an acid anhydride group, an epoxy group, an isocyanate group, a blocked isocyanate group, and a carbamide group. Dispersion. It is a method for manufacturing the polyolefin resin aqueous dispersion of Claim 1, Comprising: In the synthesis | combination of polyolefin resin (A), it is not protected with the protected primary and / or protected secondary amino group. A polyolefin resin aqueous dispersion comprising a step of reacting an amino compound (Q) containing a primary amino group with an unsaturated carboxylic acid anhydride unit of an unsaturated carboxylic acid anhydride-modified polyolefin resin (P). Body manufacturing method.