JP7193266B2 - Modified Polyolefin Resin, Aqueous Dispersion, and Primer - Google Patents

Description

The present invention relates to modified polyolefin resins, aqueous dispersions, and primers.

From the standpoint of reducing environmental impact and manufacturing costs, the materials used in the outer panel parts of automobiles are replacing conventional steel plates with plastic substrates. A coating film formed on a plastic outer plate component is required to have the same coating film performance as was conventionally required for a coating film formed on a steel plate outer plate.

On the other hand, plastic substrates are generally non-polar substrates, have low surface free energy, and when the plastic substrate has crystallinity, it is particularly difficult for the paint to adhere. In order to solve this problem, a composition containing a resin that adheres well to plastic substrates is used as a primer.

For example, Patent Document 1 describes an aqueous resin composition obtained by emulsion polymerization of a modified propylene-based random copolymer and a methacrylic acid ester monomer.

JP-A-2004-091559

High water resistance is one of the performances required for coating films on outer panel parts of automobiles. For reasons such as the need to respond to accelerated tests to evaluate high-pressure car washability and the need to respond to temperature changes in each season, the coating film must not only be resistant to water at room temperature, but also , high resistance to hot water is required.
On the other hand, water-based primers are preferable to solvent-based primers from the viewpoint of reducing environmental load.

However, coatings obtained using conventional aqueous dispersions of resins modified with (meth)acrylic acid esters, such as that disclosed in US Pat. It didn't have hot water.

Therefore, even when applied as an aqueous dispersion onto a plastic substrate, a modified polyolefin resin that has good adhesion and at the same time provides a coating film with high resistance to hot water; an aqueous dispersion; and good adhesion. There is a need for a primer that provides a coating film that is both durable and has high resistance to hot water.

In order to solve the above problems, the present inventors have conducted extensive studies. As a result, the present inventors have found that by using a polyolefin resin or a modified resin thereof with a monomer group having a glass transition temperature higher than a predetermined temperature, a coating film having high resistance to hot water can be obtained. is obtained. On the other hand, the present inventors also found that when the glass transition temperature exceeds a predetermined temperature, the adhesion of the coating film to the substrate becomes poor. As a result of further studies, the present inventors unexpectedly found that by controlling the hydroxyl value in addition to the glass transition temperature, it is possible to achieve high hot water resistance and good adhesion to the substrate. perfected the invention. That is, the inventors provide the following.

Ｔｇ（℃）＝Ｔｇ’＋２７３．１５ （２）

［２］ 重量平均分子量が、１０，０００以上１，０００，０００以下である、［１］に記載の変性ポリオレフィン樹脂。
［３］ 前記樹脂（Ａ）が、カルボン酸により、及び／又は塩素によりポリオレフィン樹脂が変性されている樹脂である、［１］又は［２］に記載の変性ポリオレフィン樹脂。
［４］ 前記樹脂（Ａ）の、単量体群（Ｂ）に対する重量比率（樹脂（Ａ）／単量体群（Ｂ））が、２０／８０以上９５／５以下である、［１］～［３］のいずれか１つに記載の変性ポリオレフィン樹脂。
［５］ ［１］～［４］のいずれか１つに記載の変性ポリオレフィン樹脂及び水を含む、水性分散体。
［６］ ［１］～［４］のいずれか１つに記載の変性ポリオレフィン樹脂を含む、プライマー。 [1] A modified product obtained by modifying the resin (A) with the monomer group (B),
The resin (A) is a polyolefin resin or a modified resin thereof,
The monomer group (B) is composed of one or more monomers selected from (meth)acrylic acid and (meth)acrylic acid esters,
The one or more monomers are respectively monomers (1) to monomers (n), the weight ratio of the monomer (n) in the monomer group (B) is Wn, and the monomers Let Tgn(K) be the glass transition temperature of the homopolymer from monomer (n), and Xn (mgKOH/g) be the hydroxyl value of the homopolymer from said monomer (n), where n is 1 or more. Given an integer,
The glass transition temperature Tg of the monomer group (B) calculated from the following formulas (1) and (2) is 50 ° C. or higher and 90 ° C. or lower,
A modified polyolefin resin in which the hydroxyl value X of the monomer group (B) calculated from the following formula (3) is 17 mgKOH/g or more and 50 mgKOH/g or less.

Tg (°C) = Tg' + 273.15 (2)

[2] The modified polyolefin resin according to [1], which has a weight average molecular weight of 10,000 or more and 1,000,000 or less.
[3] The modified polyolefin resin according to [1] or [2], wherein the resin (A) is a polyolefin resin modified with carboxylic acid and/or chlorine.
[4] The weight ratio of the resin (A) to the monomer group (B) (resin (A)/monomer group (B)) is 20/80 or more and 95/5 or less [1] The modified polyolefin resin according to any one of [3].
[5] An aqueous dispersion comprising the modified polyolefin resin according to any one of [1] to [4] and water.
[6] A primer containing the modified polyolefin resin according to any one of [1] to [4].

Ｔｇ（℃）＝Ｔｇ’＋２７３．１５ （２）

The present invention also provides the following.
[7] A method for producing a modified polyolefin resin, comprising modifying the resin (A) with the monomer group (B) to obtain a modified polyolefin resin,
The resin (A) is a polyolefin resin or a modified resin thereof,
The monomer group (B) is composed of one or more monomers selected from (meth)acrylic acid and (meth)acrylic acid esters,
The one or more monomers are respectively monomers (1) to monomers (n), the weight ratio of the monomer (n) in the monomer group (B) is Wn, and the monomers Let Tgn(K) be the glass transition temperature of the homopolymer from monomer (n), and Xn (mgKOH/g) be the hydroxyl value of the homopolymer from said monomer (n), where n is 1 or more. Given an integer,
The glass transition temperature Tg of the monomer group (B) calculated from the following formulas (1) and (2) is 50 ° C. or higher and 90 ° C. or lower,
A method for producing a modified polyolefin resin, wherein the hydroxyl value X of the monomer group (B) calculated from the following formula (3) is 17 mgKOH/g or more and 50 mgKOH/g or less.

Tg (°C) = Tg' + 273.15 (2)

ADVANTAGE OF THE INVENTION According to the present invention, a modified polyolefin resin that can provide a coating film having good adhesion and high resistance to hot water even when applied as an aqueous dispersion onto a plastic substrate; an aqueous dispersion; and It is possible to provide a primer that provides a coating film that has good adhesion and at the same time has high resistance to hot water.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to its preferred embodiments. The present invention is not limited by the following embodiments.

As used herein, "(meth)acrylic acid" means acrylic acid or methacrylic acid, or both.
As used herein, "(meth)acrylic acid ester" means acrylic acid ester or methacrylic acid ester, or both.
As used herein, a "(meth)acryloyl group" means an acryloyl group, a methacryloyl group, or both.
As used herein, "(meth)acrylate" means acrylate or methacrylate, or both.
As used herein, the term "composition" includes those consisting of only one component and those containing two or more components.
As used herein, the term "agent" includes substances consisting of only one component and substances containing two or more components.

[1. Modified polyolefin resin]
The modified polyolefin resin of the present invention is a modified product obtained by modifying the resin (A) with the monomer group (B).

[1.1. Resin (A)]
Resin (A) is a polyolefin resin or a modified resin thereof.
(polyolefin resin)
Polyolefin resins include polymers of olefins (polyolefins). The polyolefin is preferably a polyolefin obtained using a Ziegler-Natta catalyst or a metallocene catalyst as a polymerization catalyst; polypropylene obtained using a Ziegler-Natta catalyst or a metallocene catalyst as a polymerization catalyst, or propylene and an α-olefin (e.g., ethylene, butene, 3-methyl-1-butene, 3-methyl-1-heptene) is more preferable; polypropylene or propylene-based random copolymer obtained using a metallocene catalyst as a polymerization catalyst is further Preferred; even more preferred are polypropylene, ethylene-propylene copolymers, propylene-butene copolymers, or ethylene-propylene-butene copolymers obtained using metallocene catalysts as polymerization catalysts.

When a metallocene catalyst is used, the resulting polyolefin is characterized by a narrow molecular weight distribution, excellent random copolymerizability, a narrow composition distribution, and a wide range of copolymerizable comonomers.

Here, the propylene-based random copolymer refers to a polyolefin obtained by random copolymerization of propylene and α-olefin, such as ethylene-propylene copolymer, propylene-butene copolymer, ethylene-propylene-diene. copolymers, and ethylene-propylene-butene copolymers. In addition, the (co)polymer constituting the polyolefin resin may be of one type alone, or may be a combination of a plurality of (co)polymers.

A known metallocene catalyst can be used. Examples thereof include catalysts obtained by combining the following components (1) and (2), and optionally component (3). Among them, the metallocene catalyst is preferably a catalyst obtained by combining the following component (1) and component (2), and optionally component (3).
Component (1): A metallocene complex that is a transition metal compound of Groups 4 to 6 of the periodic table having at least one conjugated five-membered ring ligand.
Component (2): Ion-exchange layered silicate.
Component (3): an organoaluminum compound.

The structure of the polyolefin resin may be any of an isotactic structure, an atactic structure, a syndiotactic structure, etc., which ordinary polymer compounds can take. Among these structures, polyolefin resins having an isotactic structure, which can be obtained when a metallocene catalyst is used, are preferable in consideration of adhesion to polyolefin substrates, especially adhesion at low temperature drying.

As the component composition of the polyolefin resin, the propylene structural unit content is preferably 60% by weight or more, more preferably 70% by weight or more, and even more preferably 80% by weight or more. When the propylene component is 60% by weight or more, the adhesion (adhesion, adhesiveness) to polyolefin substrates can be better.

The propylene structural unit content in the polyolefin resin can be the ratio of propylene used in the raw material, but may be calculated by NMR analysis.

(Resin modified from polyolefin resin)
The resin (A) may be a resin obtained by modifying a polyolefin resin. The type of modification is not particularly limited. When the resin (A) is a resin obtained by modifying a polyolefin resin with multiple types of modifying materials, the modification with the multiple types of modifying materials may be performed simultaneously or sequentially.

Modification is preferably modification with carboxylic acid and/or modification with chlorine.

The resin (A) may be an acid-modified polyolefin resin obtained by modifying a polyolefin resin with a carboxylic acid.

Carboxylic acids that can be used to modify polyolefin resins are not particularly limited, but examples include α,β-unsaturated carboxylic acids and derivatives of α,β-unsaturated carboxylic acids (e.g., maleic acid, maleic anhydride, fumaric acid, , citraconic acid, citraconic anhydride, mesaconic acid, itaconic acid, itaconic anhydride, aconitic acid, aconitic anhydride, hymic anhydride, (meth)acrylic acid). Among them, the carboxylic acid is preferably an acid anhydride of an α,β-unsaturated carboxylic acid or (meth)acrylic acid, more preferably maleic anhydride or (meth)acrylic acid.

In this specification, the term "carboxylic acid" includes acid anhydrides, and "modification with carboxylic acid" includes modification with carboxylic anhydrides.

When the polyolefin resin is modified with carboxylic acid, the degree of modification with carboxylic acid (content of carboxylic acid) is preferably 1.0% by weight or more and 20% by weight or less, more preferably 1.5% by weight or more and 15% by weight. % or less, more preferably 2.5 wt % or more and 10 wt % or less.
The degree of modification with carboxylic acid (content of carboxylic acid) can be measured by a known method. For example, it can be determined by alkaline titration or Fourier transform infrared spectroscopy.

A known method can be used as a method for modifying the polyolefin resin with a carboxylic acid. For example, there is a method of melting a polyolefin resin and adding a carboxylic acid and a radical reaction initiator for modification. The reaction apparatus is not particularly limited, and for example, an extruder may be used for the modification reaction.

The resin (A) may be a chlorinated polyolefin resin obtained by modifying a polyolefin resin with chlorine.

When the polyolefin resin is chlorinated, the chlorine content of the chlorinated polyolefin resin is preferably 10% by weight or more, more preferably 15% by weight or more. The upper limit of the chlorine content is preferably 40% by weight or less, more preferably 35% by weight or less. When the chlorine content falls within the above range, the obtained modified polyolefin resin has excellent adhesion to polyolefin substrates.
It is presumed that when the chlorine content is within this range, the modified polyolefin resin tends to exhibit a linear structure due to steric repulsion between chlorine atoms. Therefore, it is presumed that the modified polyolefin resin has excellent adhesion to the substrate. The speculation does not limit the invention.

The chlorine content can be measured according to JIS-K7229.

A known method can be used as the method of modification with chlorine. For example, a method of dissolving a polyolefin resin in a chlorine-based solvent such as chloroform and then blowing in chlorine gas to introduce chlorine can be used. More specifically, for example, modification with chlorine is carried out by dispersing or dissolving a polyolefin resin in a medium such as water, carbon tetrachloride, or chloroform, in the presence of a catalyst or under irradiation with ultraviolet rays, under pressure or normal pressure, 50 It can be carried out by blowing chlorine gas in a temperature range of ~140°C.

When a chlorinated solvent is used in the chlorination, the chlorinated solvent can usually be distilled off under reduced pressure or replaced with another organic solvent.

The resin (A) may be a resin obtained by modifying a polyolefin resin with a carboxylic acid and modifying it with chlorine. Hereinafter, a resin obtained by modifying a polyolefin resin with a carboxylic acid and modifying it with chlorine is also referred to as an acid-modified chlorinated polyolefin resin.

The resin (A) may be a modified product obtained by first modifying a polyolefin resin with a carboxylic acid and then modifying it with chlorine, or it may be a modified product obtained by first modifying a polyolefin resin with chlorine. and then modified with carboxylic acid.

As a method for producing the acid-modified chlorinated polyolefin resin, for example, the acid-modified polyolefin resin obtained by the above method is modified by the modification method with chlorine, or the chlorinated polyolefin resin obtained by the above method is modified. On the other hand, there is a method of modifying by the modification method with carboxylic acid.

The resin (A) may be in a form containing any additive. For example, the resin (A) may be in a form containing a stabilizer.

Optional stabilizers include, for example, epoxy compounds; metal soaps such as calcium stearate and lead stearate used as stabilizers for polyvinyl chloride resins; organometallic compounds such as dibutyltin dilaurate and dibutyltin malate. and hydrotalcite compounds.

The epoxy compound is not particularly limited, but an epoxy compound compatible with the resin (A) is preferable. Examples thereof include compounds having an epoxy equivalent of about 100 to 500 and having one or more epoxy groups per molecule.

Examples of such epoxy compounds include epoxidized vegetable oils (epoxidized soybean oil, epoxidized linseed oil, etc.) obtained by epoxidizing a vegetable oil having a natural unsaturated group with a peracid such as peracetic acid; oleic acid; Epoxidized fatty acid esters obtained by epoxidizing unsaturated fatty acids such as tall oil fatty acid and soybean oil fatty acid; epoxidized alicyclic compounds such as epoxidized tetrahydrophthalate; Ethers such as bisphenol A glycidyl ether, ethylene glycol glycidyl ether, propylene glycol glycidyl ether, glycerol polyglycidyl ether, sorbitol polyglycidyl ether; butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, stearyl glycidyl ether monoepoxy compounds typified by ether, allyl glycidyl ether, phenyl glycidyl ether, sec-butylphenyl glycidyl ether, tert-butylphenyl glycidyl ether, phenol polyethylene oxide glycidyl ether and the like;

The stabilizer may be used alone or in combination of two or more.

When the resin (A) is modified with the monomer group (B) in a form containing an optional stabilizer, the weight ratio of the stabilizer to the resin (A) should be 1 to 20% by weight (in terms of solid content). is preferred.

The lower limit of the weight average molecular weight (Mw) of resin (A) is preferably 10,000 or more. When the weight average molecular weight is 10,000 or more, the resulting composition containing the modified polyolefin resin has sufficient cohesion, and the resin composition can be excellent in adhesion to substrates. Moreover, the upper limit is preferably 150,000 or less. When the weight-average molecular weight is 150,000 or less, when the obtained modified polyolefin resin is blended with other resins to form a resin composition, the modified polyolefin resin and the other resins have good compatibility, and the resin composition is improved. The product can have excellent adhesion to the substrate.

The weight average molecular weight of resin (A) can be determined from a standard polystyrene calibration curve by gel permeation chromatography (GPC).

[1.2. Monomer group (B)]
The monomer group (B) is composed of one or more monomers selected from (meth)acrylic acid and (meth)acrylic acid esters.

The (meth)acrylic acid ester contains at least one (meth)acryloyl group, preferably one (meth)acryloyl group, in the molecule.

(Glass transition temperature of monomer group (B))
The glass transition temperature Tg of the monomer group (B) is usually 50°C or higher and 90°C or lower, preferably 55°C or higher, more preferably 60°C or higher, preferably 85°C or lower, more preferably 80°C. It is below.
The glass transition temperature Tg of the monomer group (B) is at least the lower limit value, so that the adhesion (adhesion, adhesion) of the coating film to the substrate after immersing the coating film in warm water is It becomes good, and the hot water resistance of the coating film can be improved. The reason for this is that when the glass transition temperature Tg of the monomer group (B) is equal to or higher than the temperature of hot water, softening of the coating film is suppressed when the coating film is immersed in warm water, and the coating film and the substrate are It is thought that this is because the adhesiveness with is improved. However, the above reasons do not limit the present invention.

When the glass transition temperature Tg of the monomer group (B) is equal to or lower than the upper limit value, the coating film is imparted with appropriate flexibility, and the adhesion of the coating film to the substrate (adhesion, adhesion ) becomes good.

Here, the glass transition temperature Tg of the monomer is a value calculated from the following formulas (1) and (2). The following formula (1) is called the FOX formula.

Tg (°C) = Tg' + 273.15 (2)

In the above formula (1),
Wn is the monomer (n) in the monomer group (B) when the monomers constituting the monomer group (B) are the monomers (1) to (n), respectively. represents the weight percentage of
Tgn represents the glass transition temperature (K) of a homopolymer from monomer (n).
The total weight ratio of each of the monomers constituting the monomer group (B) is 1.

As the glass transition temperature of the homopolymer from the monomer (n), Tg listed in Polymer Handbook (Wiley-Interscience Publication, 4th Edition, 1999) and product data can be used.

The glass transition temperature (°C) of the monomer group (B) in the examples is also a value calculated by the above formulas (1) and (2).

(Hydroxyl value of monomer group (B))
The hydroxyl value X of the monomer group (B) is usually 17 mgKOH/g or more and 50 mgKOH/g or less, preferably 18 mgKOH/g or more, more preferably 19 mgKOH/g or more, preferably 45 mgKOH/g or less, and more Preferably, it is 40 mgKOH/g or less.
When the hydroxyl value X falls within the above range, the modified polyolefin resin has good dispersibility in a water-containing medium, and the modified polyolefin resin can be made into a stable aqueous dispersion.

When the modified polyolefin resin is used as a component of the primer, the adhesion (adhesion) of the topcoat paint to the base material is improved by setting the hydroxyl value X to the lower limit value or more.
The reason for this is thought to be that an interaction such as a cross-linking reaction occurs between the modified polyolefin resin and components in the topcoat paint. Examples of interactions include cross-linking reactions with isocyanate components often used as curing agents in topcoats. However, the above reasons do not limit the present invention.

When the hydroxyl value X is equal to or less than the above upper limit, the glass transition temperature of the monomer group (B) can be adjusted to an appropriate temperature, and the hot water resistance of the coating film can be improved. Also, the stability of the aqueous dispersion containing the modified polyolefin resin is improved.
The reason for this is as follows. If the hydroxyl value X exceeds the above upper limit, when the modified polyolefin resin is made into an aqueous dispersion, the hydroxyl groups appearing on the surface of the dispersed particles will interact with each other, and the dispersed particles will associate with each other. Therefore, it is considered that when the hydroxyl value X is equal to or less than the upper limit, the aggregation of the dispersed particles is suppressed, and the stability of the aqueous dispersion is improved. However, the above reasons do not limit the present invention.

Here, the hydroxyl value X is a value calculated from the following formula (3).

In the above formula (3),
Wn is the same as defined in the above formula (1),
Xn represents the hydroxyl value (mgKOH/g) of the homopolymer from the monomer (n).

The hydroxyl value of the homopolymer from monomer (n) is usually the same as the hydroxyl value of monomer (n). The hydroxyl value is usually obtained by converting the amount (mol) of hydroxyl groups in 1 g of the monomer to the weight of potassium hydroxide.

Usually, in the monomer group (B), by increasing the content of a monomer having a large hydroxyl value, the hydroxyl value X can be increased, and by decreasing the content of a monomer having a large hydroxyl value, hydroxyl group value X can be reduced.

The hydroxyl value of the monomer group (B) in the examples is also a value calculated by the above formula (3).

The (meth)acrylic acid esters that can constitute the monomer group (B) may have functional groups such as hydroxyl groups, carboxyl groups, alkoxysilyl groups, amide groups, and sulfanyl groups. (Meth)acrylic ester may have only one type of functional group other than the ester group (group represented by -(C=O)-O-) and the carbon-carbon double bond, You may have 2 or more types. Here, an amide group means an atomic group remaining after removing one hydrogen atom bonded to a nitrogen atom from an amide.
(Meth) acrylic acid ester has an ester group (group represented by -(C=O) -O-) and a carbon-carbon double bond, by having a functional group, the coating film to the substrate Adhesiveness (adhesion) can be improved.

The monomer group (B) preferably contains a (meth)acrylic acid ester having a hydroxy group as a functional group other than the ester group and the carbon-carbon double bond.

Examples of (meth)acrylic acid esters that can constitute the monomer group (B) include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, cyclohexyl (meth)acrylate, 2 - methoxyethyl (meth)acrylate, hydroxyethyl (meth)acrylate (e.g. 2-hydroxyethyl (meth)acrylate), isobornyl (meth)acrylate, glycidyl (meth)acrylate, octyl (meth)acrylate, lauryl (meth)acrylate , tridecyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate acrylates, acetoacetoxyethyl (meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, tripropylene glycol ( meth)acrylates, and neopentyl glycol (meth)acrylates.

[1.3. Resin (A)/monomer group (B)]
The weight ratio of the resin (A) to the monomer group (B) (resin (A)/monomer group (B)) is preferably 20/80 or more, more preferably 30/70 or more. is 95/5 or less, more preferably 90/10 or less, still more preferably 70/30 or less, preferably 20/80 or more and 95/5 or less, more preferably 30/70 or more and 90/10 or less is.
When the weight ratio of the resin (A) to the monomer group (B) is within the above range, the adhesion (adhesion) of the coating film to the substrate is excellent, and the resistance to hot water is improved.

[1.4. Denaturation method]
The method for modifying the resin (A) with the monomer group (B) is not particularly limited, and conventionally known methods can be used. For example, any of the following solution method, melt method, and emulsion polymerization can be employed as the modification method.

(solution method)
In the solution method, the resin (A) is dispersed in an organic solvent and modified with the monomer group (B).
According to the solution method, a uniform graft polymer can be obtained with less side reactions.
Specific operations are exemplified below. First, the resin (A) is dissolved in an organic solvent, and then the resin (A) and the monomer group (B) are heated and stirred in the presence of a reaction initiator (radical generator) to obtain a modified polyolefin resin.

Examples of organic solvents used in the solution method include aromatic hydrocarbon solvents (eg, toluene, xylene). The reaction temperature in the solution method is preferably 60°C or higher and 180°C or lower.

(Melting method)
In the melting method, the resin (A) is heated and melted to modify the resin (A) with the monomer group (B).
According to the melting method, the operation is simple and the reaction time can be shortened compared to other methods.
Specific operations are exemplified below. The resin (A) and the reaction initiator (radical generator) are heat-melted (heat-melted) and reacted with the monomer group (B) to obtain a modified polyolefin resin.

The temperature for heating and melting in the melting method is usually the melting point of the resin (A) or higher, preferably the melting point of the resin (A) or higher and 300° C. or lower. For heating and melting, conventionally known equipment such as a Banbury mixer, a kneader, and an extruder can be used.

(emulsion polymerization)
Emulsion polymerization can easily increase the weight-average molecular weight of the modified polyolefin resin and effectively improve the adhesion (adhesion) of the coating film to the substrate.
Specific operations are exemplified below. A composition obtained by mixing an aqueous dispersion of the resin (A), a reaction initiator (radical generator), a surfactant, and an auxiliary agent is prepared, and the monomer group (B) is added and reacted. , to obtain a modified polyolefin resin.

The aqueous dispersion of resin (A) can be prepared using the same preparation method, the same surfactant, and the same auxiliary agent as the aqueous dispersion containing the modified polyolefin resin described later.

Examples of reaction initiators (radical generators) that can be used when modifying the resin (A) with the monomer group (B) include compositions containing organic peroxides, compositions containing azonitriles, and Compositions comprising persulfates are included.

Examples of organic peroxides include di-tert-butyl peroxide, dicumyl peroxide, tert-butylcumyl peroxide, benzoyl peroxide, dilauryl peroxide, 2,5-dimethyl-2,5-di( tert-butylperoxy)hexane, cumene hydroperoxide, tert-butyl hydroperoxide, 1,1-bis(tert-butylperoxy)-3,5,5-trimethylcyclohexane, 1,1-bis(tert- butylperoxy)-cyclohexane, cyclohexanone peroxide, tert-butylperoxybenzoate, tert-butylperoxyisobutyrate, tert-butylperoxy-3,5,5-trimethylhexanoate, tert-butylperoxy- 2-ethylhexanoate, tert-butyl peroxyisopropyl carbonate, and cumyl peroxyoctoate.

Azonitriles include, for example, azobisisobutyronitrile and 1,1'-azobis(cyclohexanecarbonitrile).

Persulfates include, for example, ammonium persulfate, sodium persulfate, and potassium persulfate.

A commercially available product can be used as the reaction initiator. Commercially available products include, for example, "PERBUTYL O" manufactured by NOF Corporation.

As the reaction initiator (radical generator), a substance having an appropriate half-life temperature can be appropriately selected according to the temperature at which the radical polymerization is performed. In addition, as the reaction initiator, a substance having appropriate solubility in the reaction medium (eg, organic solvent, water) can be appropriately selected.

[1.5. Modified polyolefin resin]
The modified polyolefin resin may contain substances other than the modified olefin polymer.
For example, the modified polyolefin resin includes by-products that may be generated when the raw material polyolefin resin is modified, by-products that may be generated when the resin (A) is modified with the monomer group (B), and during the modification reaction. may contain unreacted raw materials.

The weight average molecular weight of the modified polyolefin resin is preferably 10,000 or more, more preferably 20,000 or more, and preferably 1,000,000 or less, more preferably 200,000 or less.

When the weight-average molecular weight of the modified polyolefin resin is at least the above lower limit, the cohesive force of the modified polyolefin resin is sufficient, and the resin can be excellent in adhesion to the substrate.
Since the weight average molecular weight of the modified polyolefin resin is equal to or less than the upper limit, when the modified polyolefin resin is blended with another resin to form a resin composition, the modified polyolefin resin and the other resin have good compatibility. As a result, the resin composition can be excellent in adhesion to the substrate.

The weight average molecular weight of the modified polyolefin resin can be determined from a standard polystyrene calibration curve by gel permeation chromatography (GPC).

[2. Applications of Modified Polyolefin Resin]
The modified polyolefin resin of the present invention can be used as adhesives for metals and/or resins, primers, binders for paints, binders for inks, and the like. Among others, the modified polyolefin resin of the present invention has good adhesion to plastic substrates and can provide a primer capable of forming a coating film having excellent resistance to hot water. is useful as a primer for coating plastic substrates.

[3. Resin composition]
The modified polyolefin resin may be in the form of a resin composition containing other components such as any solvent (including dispersion medium) and any additives.

[3.1. Aqueous Dispersion]
For example, the modified polyolefin resin can be in the form of an aqueous dispersion, in which the resin is dispersed in a solvent containing water.

(Components that can be contained in the aqueous dispersion)
The aqueous dispersion contains a modified polyolefin resin and water, and optionally contains optional ingredients. Optional ingredients include, for example, organic solvents, surfactants, coagents, and crosslinkers. Optional ingredients are discussed further below.

(Method for obtaining aqueous dispersion)
Methods of obtaining an aqueous dispersion containing a modified polyolefin resin include, for example, a method of dispersing the modified polyolefin resin in a dispersion medium containing water, and a method of dispersing the resin (A) in the form of an aqueous dispersion into the monomer group (B). and emulsion polymerization to directly obtain the modified polyolefin resin as an aqueous dispersion.

As a method for making the resin (A) and the modified polyolefin resin into an aqueous dispersion, a conventionally known method can be used, and examples thereof include a forced emulsification method, a phase inversion emulsification method, a D-phase emulsification method, and a gel emulsification method. be done.

Specifically, for example, a method of dispersing the resin (A) or modified polyolefin resin in an organic solvent, and then adding a surfactant, an auxiliary agent, and water to form an aqueous dispersion, and more specifically, Examples include a method of adding components other than water (surfactants, auxiliaries, etc.) to the resin (A) or modified polyolefin resin dispersed in an organic solvent, mixing the mixture, and then adding water. .

When adding and mixing the components other than water, heating (for example, 50 to 200° C.) may be performed as necessary. After adding water, the solids content of the composition may be adjusted as needed (eg, 15-50 wt %).

(Surfactant)
The aqueous dispersion may and preferably contains a surfactant.
Examples of surfactants include nonionic surfactants and anionic surfactants, and nonionic surfactants are preferred because they can maintain good water resistance of the coating film.

Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylene alkyl ethers, polyoxyethylene derivatives, polyoxyethylene fatty acid esters, polyoxyethylene polyhydric alcohol fatty acid esters, polyoxyethylene propylene polyols, polyoxyethylene Ethylene sorbitan fatty acid ester, polyoxyethylene hydrogenated castor oil, polyoxyalkylene polycyclic phenyl ether, polyoxyethylene alkylamine, alkyl alkanolamide, polyalkylene glycol (meth)acrylate, preferably polyoxyethylene alkyl ether, poly They are oxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acid esters and polyoxyethylene alkylamines, and particularly preferably polyoxyethylene alkylamines. The said nonionic surfactant may be used individually by 1 type, or may be used in mixture of 2 or more types.

Examples of anionic surfactants include alkyl sulfates, polyoxyethylene alkyl ether sulfates, alkylbenzene sulfonates, α-olefin sulfonates, methyl taurine salts, sulfosuccinates, ether sulfonates, and ether carboxylic acids. Salts, fatty acid salts, naphthalenesulfonic acid formalin condensates, alkylamine salts, quaternary ammonium salts, alkylbetaines, and alkylamine oxides, preferably polyoxyethylene alkyl ether sulfates and sulfosuccinates. The anionic surfactants may be used singly or in combination of two or more.

The amount of the surfactant added is preferably 0.1 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, relative to 100 parts by weight of the resin (A) or modified polyolefin resin. It is more preferable to have When the amount of the surfactant added is equal to or less than the above upper limit, the adhesion (adhesion) and water resistance of the coating film obtained from the aqueous dispersion are improved, and the plasticity of the coating film is suppressed, and the surfactant It is possible to suppress the bleeding of the coating film and suppress the occurrence of blocking of the coating film.

As a surfactant, a glycol monoalkyl ether compound may be used in place of or in addition to the nonionic surfactants and anionic surfactants. Since the compound has both a hydrophobic group and a hydrophilic group in one molecule, the resin component can be easily dispersed or emulsified in water, and the resulting aqueous dispersion can maintain good storage stability.

Glycol monoalkyl ethers include, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, ethylene glycol mono-t-butyl ether. , ethylene glycol monohexyl ether, ethylene glycol monodecyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, and propylene glycol monobutyl ether, among which ethylene glycol monobutyl ether (butyl cellosolve), propylene Glycol monomethyl ether and propylene glycol monopropyl ether are preferred, and propylene glycol monomethyl ether, ethylene glycol monobutyl ether and propylene glycol monopropyl ether are more preferred.

The molecular weight of the glycol monoalkyl ether compound is preferably less than 200. As a result, it is possible to suppress the increase in the boiling point of the aqueous dispersion, so in the process of drying the coating film obtained from the aqueous dispersion or the primer containing the aqueous dispersion, the drying time can be shortened and the drying temperature can be lowered. sell.

Glycol monoalkyl ether compounds may be used singly or in combination of two or more at any ratio.

(auxiliary agent)
When the resin (A) is a resin modified with a carboxylic acid, it is preferable to add a basic substance as an auxiliary agent to the aqueous dispersion. As a result, the carboxyl groups in the resin component are neutralized appropriately, and the resin component becomes easier to disperse in water, so that the storage stability of the aqueous dispersion can be improved.

Basic substances include, for example, ammonia, methylamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, isobutylamine, hexylamine, octylamine, ethanolamine, propanolamine, diethanolamine, N -methyldiethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N-dibutylethanolamine, 2-dimethylamino-2-methyl-1-propanol, 2-amino-2-methyl-1 -propanol, 2-aminoethanol, 2-dimethylaminoethanol, 2-diethylaminoethanol, 3-ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, propylamine, n-butylamine, 2-methoxyethylamine, 3-methoxy Propylamine, 2,2-dimethoxyethylamine, monoethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine, piperazines, pyrrole, pyridine, alkali metal compounds (e.g. sodium hydroxide, potassium hydroxide), alkaline earth Metallic compounds (eg, magnesium hydroxide) can be mentioned. Among them, morpholine, N,N-dimethylethanolamine, N,N-diethylethanolamine, and 2-amino-2-methyl-1-propanol are preferred from the viewpoint of ease of emulsification and dispersion.

The boiling point of the basic substance under normal pressure is preferably 200° C. or lower. As a result, for example, in the step of drying a coating film obtained from an aqueous dispersion or a primer containing an aqueous dispersion, the basic substance can be easily removed at a low temperature, and when the coating film is dried at a low temperature It is possible to improve the water resistance and moisture resistance of the coating film, and the adhesion (adhesiveness) to substrates such as non-polar resin molded products.

The basic substance may be used singly or in combination of two or more at any ratio.

The pH of the aqueous dispersion is preferably 6 or higher and preferably 12 or lower. As a result, the compatibility between the resin and other components that can be incorporated in the aqueous dispersion is improved, and the water resistance and humidity resistance of the coating film obtained from the aqueous dispersion are improved. In addition, the work of preparing the aqueous dispersion can be easily carried out.

In the aqueous dispersion, the average particle size of the resin (A) or modified polyolefin resin dispersed and emulsified in water is preferably 0.3 μm or less. As a result, the storage stability of the aqueous dispersion is improved, and the compatibility between the resin and other components that can be incorporated in the aqueous dispersion is improved. In addition, the properties of the coating film obtained from the aqueous dispersion (for example, adhesion to substrates such as non-polar resin molded products, solvent resistance, water resistance, moisture resistance, blocking resistance) are improved.

In the present specification, the average particle size can be measured by particle size distribution measurement using a dynamic light scattering method, and as a measuring instrument for this, for example, Malvern's "Zetasizer" can be used.

The aqueous dispersion may contain a cross-linking agent. Here, the cross-linking agent means a compound that forms a cross-linked structure by reacting with a functional group such as a hydroxyl group, a carboxyl group, or an amino group present in a modified polyolefin resin, a basic substance, or the like.

The cross-linking agent may be water soluble or in some form dispersed in water.

Crosslinking agents include, for example, blocked isocyanate compounds, aliphatic or aromatic epoxy compounds, amine compounds, and amino resins. The cross-linking agent may be used singly or in combination of two or more at any ratio. The timing of addition of the cross-linking agent is not particularly limited, and examples thereof include during the process of dispersing the modified polyolefin resin in an aqueous medium (aqueous process) or after the aqueous process.

[3.2. Use of Aqueous Dispersion]
Aqueous dispersions containing modified polyolefin resins have good adhesion to plastic substrates and can form coating films with excellent hot water resistance. It is useful as a primer for painting materials.

"4. Manufacturing method of modified polyolefin resin]
A method for producing a modified polyolefin resin according to the present embodiment includes modifying resin (A) with a monomer group (B) to obtain a modified polyolefin resin.
Examples and preferred examples of the resin (A) and the monomer group (B) are described in [1. modified polyolefin resin].
Examples and preferred examples of the method for modifying the resin (A) with the monomer group (B) are described in [1.4. Modification method].

EXAMPLES The present invention will be described in detail below with reference to examples. The following examples are intended to better illustrate the present invention and are not intended to limit the present invention. Unless otherwise specified, the method for measuring physical properties is the method described above. Also, "parts" are in terms of weight unless otherwise specified.

[Weight average molecular weight (Mw)]:
It was measured by GPC under the following conditions.
Apparatus: HLC-8320GPC (manufactured by Tosoh Corporation)
Column: TSK-gel G-6000 H × L, G-5000 H × L, G-4000 H × L, G-3000 H × L, G-2000 H × L (manufactured by Tosoh Corporation)
Eluent: THF
Flow rate: 1 mL/min
Temperature: pump oven, column oven 40°C
Injection volume: 100 μL
Standard material: polystyrene EasiCal PS-1 (manufactured by Agilent Technology)

[Degree of modification with maleic anhydride (%)]
It was measured by a method according to JIS K 0070 using an alkaline titration method.

[Weight ratio of resin (A) to monomer group (B)]
It was calculated from the amount of each component used.

<Preparation of test piece>
The surface of an ultra-high-rigidity polypropylene plate was degreased with isopropyl alcohol, an aqueous dispersion of a modified polyolefin resin was spray-coated so that the dry film thickness was 10 μm or more and 15 μm or less, and preheated at the melting point of the resin +15° C. for 5 minutes. Next, a 1K water-based base containing the modified polyolefin resin aqueous dispersion was spray-coated, allowed to stand for 10 minutes, and then a 2K water-based clear was applied. After that, baking treatment was performed for 30 minutes at the melting point of the resin +15°C to prepare a test piece.
The following tests were performed using this test piece.

[Warm water resistance test]:
After the test piece was immersed in a constant temperature water bath at 60°C for 1 month, a cellophane adhesive tape was adhered to the coating film surface and peeled off in a 180° direction. did.
A: No peeling of coating film.
B: The area of the peeled coating film is more than 1% and 10% or less.
C: The area of the peeled coating film is more than 10% and 50% or less.
D: The area of the peeled coating film is more than 50%.

[Adhesion test]:
Line-shaped notches reaching the substrate at intervals of 1 mm were placed vertically and horizontally in the coating film of the test piece to form 100 sections (grid), and a cellophane adhesive tape was adhered thereon and peeled off in the 180° direction. . The cellophane pressure-sensitive adhesive tape was brought into close contact with the tape and peeled off 10 times per 100 identical sections, and the adhesiveness (adhesiveness) was evaluated according to the following criteria. If the number of partitions of the peeled coating film is 50 or less, there is no practical problem.
A: No peeling of coating film.
B: 1 or more and 10 or less sections of the peeled coating film.
C: More than 10 and 50 or less sections of the peeled coating film.
D: More than 50 sections of the peeled coating film.

[Gasohol resistance test]
The test piece was immersed in regular gasoline/ethanol = 9/1 (v/v) for 120 minutes, the state of the coating film was observed, and gasohol resistance was evaluated according to the following criteria. If no peeling occurs on the coating film surface, there is no practical problem.
A: There is no change in the coating film surface.
B: A slight change is observed on the surface of the coating film, but no peeling is observed.
C: A change was observed on the surface of the coating film, but no peeling occurred.
D: Peeling has occurred on the surface of the coating film.

[Comprehensive evaluation]
In each of the above tests (hot water resistance test, adhesion test, gasohol resistance test), if the test results are within the range of A to C, there is no practical problem. If the test result is D for even one item, it is not suitable for practical use.

[Production Example 1: Production of acid-modified chlorinated polyolefin resin (A-1) as resin (A)]:
100 parts of a propylene-based random copolymer (propylene structural unit content: 96% by weight, ethylene structural unit content: 4% by weight) as a polyolefin resin produced using a metallocene catalyst as a polymerization catalyst, and carboxylic acid (α, β - 10 parts of maleic anhydride as an unsaturated carboxylic acid cyclic anhydride), 2 parts of di-t-butyl peroxide as a reaction initiator (radical generator) are uniformly mixed, and a twin-screw extruder (L/ D=60, diameter=15 mm, barrels 1 to 14).

Residence time of 10 minutes, rotation speed of 200 rpm, barrel temperature of 100°C (1st and 2nd barrels), 200°C (3rd to 8th barrels), 90°C (9th and 10th barrels), 110°C (11th to 14th barrels) The reaction was carried out under the conditions of the barrel). After that, vacuum treatment was performed to remove unreacted maleic anhydride to obtain an acid-modified polypropylene resin modified with maleic anhydride.

100 parts of the acid-modified polypropylene resin was charged into a glass-lined reactor. Chloroform was added, and the resin was sufficiently dissolved at a temperature of 110°C under a pressure of 2 kgf/cm ² . Chlorination was performed by blowing chlorine gas while controlling the pressure to 2 kgf/cm ² .

After completion of the reaction, 6 parts of an epoxy compound (Eposizer W-100EL, manufactured by Dainippon Ink and Chemicals, Inc.) was added as a stabilizer, supplied to a vented extruder equipped with a solvent removal suction part in the screw shaft, and removed. Solvented and solidified to obtain an acid-modified chlorinated polypropylene resin as an acid-modified chlorinated polyolefin resin. The resulting acid-modified chlorinated polyolefin resin had a weight average molecular weight of 150,000, a degree of modification with maleic anhydride of 10% by weight, and a chlorine content of 35% by weight.

[Production Example 2: Production of chlorinated polyolefin resin (A-2) as resin (A)]:
100 parts of a propylene-based random copolymer (propylene structural unit content: 80% by weight, ethylene structural unit content: 20% by weight) as a polyolefin resin produced using a metallocene catalyst as a polymerization catalyst was placed in a glass-lined reactor. was put into Chloroform was added and the resin was sufficiently dissolved at a temperature of 110°C under a pressure of 2 kgf/cm ² , then 4 parts of azobisisobutyronitrile was added as a radical generator, and the pressure inside the vessel was adjusted to 3 kgf/cm ² . Chlorination was carried out by blowing in chlorine gas in a controlled manner.

After completion of the reaction, 6 parts of an epoxy compound (Eposizer W-100EL, manufactured by Dainippon Ink and Chemicals, Inc.) was added as a stabilizer, supplied to a vented extruder equipped with a solvent removal suction part in the screw shaft, and removed. Solvented and solidified to obtain chlorinated polypropylene resin (A-2). The resulting chlorinated polyolefin resin had a weight average molecular weight of 10,000 and a chlorine content of 15% by weight.

[Production Example 3: Production of acid-modified polyolefin resin (A-3) as resin (A)]:
100 parts of a propylene-based random copolymer (propylene structural unit content: 80% by weight, ethylene structural unit content: 20% by weight) as a polyolefin resin produced using a metallocene catalyst as a polymerization catalyst, and carboxylic acid (α, β - 5 parts of maleic anhydride as an unsaturated polycarboxylic acid cyclic anhydride), 6 parts of di-t-butyl peroxide as a reaction initiator (radical generator) are uniformly mixed, and a twin-screw extruder (L /D = 60, diameter = 15 mm, barrels 1 to 14).

Residence time of 10 minutes, rotation speed of 200 rpm, barrel temperature of 100°C (1st and 2nd barrels), 200°C (3rd to 8th barrels), 90°C (9th and 10th barrels), 110°C (11th to 14th barrels) The reaction was carried out under the conditions of the barrel). After that, vacuum treatment was performed to remove unreacted maleic anhydride to obtain an acid-modified polypropylene resin modified with maleic anhydride. The resulting acid-modified polyolefin resin had a weight average molecular weight of 10,000 and a degree of modification with maleic anhydride of 2% by weight.

[Production Example 4: Production of polyolefin resin (A-4) as resin (A)]:
100 parts of a propylene-based random copolymer (propylene structural unit content: 80% by weight, ethylene structural unit content: 20% by weight) as a polyolefin resin produced using a metallocene catalyst as a polymerization catalyst; - 6 parts of t-butyl peroxide were uniformly mixed and fed into a twin-screw extruder (L/D = 60, diameter = 15 mm, barrels 1 to 14).

Residence time of 10 minutes, rotation speed of 200 rpm, barrel temperature of 100°C (1st and 2nd barrels), 200°C (3rd to 8th barrels), 90°C (9th and 10th barrels), 110°C (11th to 14th barrels) A polyolefin resin (A-4) was obtained by carrying out the reaction under the conditions of barrel). The obtained polyolefin resin had a weight average molecular weight of 10,000.

A list of (modified) polyolefin resins produced in Production Examples 1 to 4 is shown in Table 1 below.

[Example 1: Production of aqueous dispersion of resin (C-1)]
((Meth)acrylic acid ester modification of acid-modified chlorinated polyolefin resin (A-1))
100 parts of acid-modified chlorinated polyolefin resin (A-1) as resin (A) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (41.1 parts of cyclohexyl methacrylate, 1.2 parts of 2-hydroxyethyl acrylate) as the monomer group (B) represented by component B-1 shown in Table 2 were added. 7 parts) was added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-1). The modified polyolefin resin (C-1) had a weight average molecular weight of 200,000.

(Preparation of aqueous dispersion of resin (C-1))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-1) of a modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-1) by gas chromatography, it was 1% by weight or less relative to the modified polyolefin resin aqueous dispersion composition (D-1).

[Example 2: Production of aqueous dispersion of resin (C-2)]
((Meth)acrylic acid ester modification of chlorinated polyolefin resin (A-2))
100 parts of chlorinated polyolefin resin (A-2) as resin (A) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (8.9 parts of cyclohexyl methacrylate, 1 part of 2-methoxyethyl acrylate) as the monomer group (B) represented by component B-2 shown in Table 2 .3 parts and 0.9 parts of 2-hydroxyethyl acrylate) were added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-2). The modified polyolefin resin (C-2) had a weight average molecular weight of 20,000.

(Preparation of aqueous dispersion of resin (C-2))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain a modified polyolefin resin aqueous dispersion composition (D-2). As a result of confirming the content of toluene in the aqueous dispersion composition (D-2) by gas chromatography, it was 1% by weight or less relative to the aqueous dispersion composition (D-2).

[Example 3: Production of aqueous dispersion of resin (C-3)]
(Preparation of aqueous dispersion of acid-modified chlorinated polyolefin resin (A-1))
100 parts of acid-modified chlorinated polyolefin resin (A-1) as resin (A) and 25 parts of toluene are melted and kneaded at 90° C. for 30 minutes to obtain 75 parts of propylene glycol monomethyl ether and 2-amino-2-methyl-1. - 7 parts of propanol were added. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion (A-1a) of an acid-modified chlorinated polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion (A-1a) by gas chromatography, it was 1% by weight or less relative to the aqueous dispersion (A-1a).

(Emulsion polymerization of aqueous dispersion (A-1a) of acid-modified chlorinated polyolefin resin)
350 parts of ion-exchanged water, 4.0 g of sodium lauryl sulfate, and 4.0 parts of ammonium persulfate are added to 333 parts of the aqueous dispersion of acid-modified chlorinated polyolefin resin (A-1a), and the mixture is heated to 70° C. under a nitrogen atmosphere. After warming, (meth)acrylic acid ester monomers (129 parts of cyclohexyl methacrylate, 96.0 parts of n-butyl methacrylate) as monomer group (B) represented by composition B-3 shown in Table 2 and 9.7 parts of 2-hydroxyethyl acrylate) were added over about 45 minutes and kept at 70° C. for 6 hours to obtain a dispersion of modified polyolefin resin (C-3). The dispersion of (C-3) was cooled, an appropriate amount of deionized water was added, and then blown to obtain an aqueous dispersion composition (D-3) of the modified polyolefin resin (C-3) having a solid content of about 30%. .
The weight average molecular weight of the modified polyolefin resin (C-3) was 1,000,000.

[Example 4: Production of aqueous dispersion of resin (C-4)]
((Meth)acrylic acid ester modification of polyolefin resin (A-4))
100 parts of polyolefin resin (A-4) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC Corporation) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (41.1 parts of cyclohexyl methacrylate, 1.2 parts of 2-hydroxyethyl acrylate) as monomer group (B) represented by composition B-1 shown in Table 2 were added. 7 parts) was added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-4). The modified polyolefin resin (C-4) had a weight average molecular weight of 20,000.

(Preparation of aqueous dispersion of modified polyolefin resin (C-4))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-4) of a modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-4) by gas chromatography, it was 1% by weight or less with respect to the modified polyolefin resin aqueous dispersion composition (D-4).

[Example 5: Production of aqueous dispersion of resin (C-5)]
((Meth)acrylic acid ester modification of acid-modified polyolefin resin (A-3))
100 parts of acid-modified polyolefin resin (A-3) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (41.1 parts of cyclohexyl methacrylate, 1.2 parts of 2-hydroxyethyl acrylate) as monomer group (B) represented by composition B-1 shown in Table 2 were added. 7 parts) was added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-5). The modified polyolefin resin (C-5) had a weight average molecular weight of 10,000.

(Preparation of aqueous dispersion of resin (C-5))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-5) of modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-5) by gas chromatography, it was 1% by weight or less with respect to the modified polyolefin resin aqueous dispersion composition (D-5).

[Comparative Example 1: Production of aqueous dispersion of resin (C-6)]
(Meth)acrylic ester-modified acid-modified chlorinated polyolefin resin (A-1) of modified polyolefin resin (A-1) is dissolved in 50 parts of toluene, and an epoxy compound (Eposizer W-131, manufactured by DIC Corporation) is dissolved. Added 5 parts. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (21.4 parts of n-butyl methacrylate, 2-methoxy acrylate 21.4 parts of ethyl) was added, and the reaction was carried out at 85° C. for 6 hours to obtain a modified polyolefin resin (C-6). The modified polyolefin resin (C-6) had a weight average molecular weight of 200,000.

(Preparation of aqueous dispersion of resin (C-6))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-6) of modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-6) by gas chromatography, it was 1% by weight or less with respect to the modified polyolefin resin aqueous dispersion composition (D-6).

[Comparative Example 2: Production of aqueous dispersion of resin (C-7)]
((Meth)acrylic acid ester modification of acid-modified chlorinated polyolefin resin (A-1))
100 parts of acid-modified chlorinated polyolefin resin (A-1) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (19.7 parts of cyclohexyl methacrylate, 21 parts of n-butyl methacrylate) as the monomer group (B) represented by component B-5 in Table 2 were added. 4 parts and 1.7 parts of 2-hydroxyethyl acrylate) were added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-7). The modified polyolefin resin (C-7) had a weight average molecular weight of 190,000.

(Preparation of aqueous dispersion of resin (C-7))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-7) of modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-7) by gas chromatography, it was 1% by weight or less with respect to the modified polyolefin resin aqueous dispersion composition (D-7).

[Comparative Example 3: Production of aqueous dispersion of resin (C-8)]
((Meth)acrylic acid ester modification of acid-modified chlorinated polyolefin resin (A-1))
100 parts of acid-modified chlorinated polyolefin resin (A-1) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester monomers (41.1 parts of methyl methacrylate, 1 part of 2-hydroxyethyl acrylate) as the monomer group (B) represented by component B-6 in Table 2 .7 parts) was added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-8). The modified polyolefin resin (C-8) had a weight average molecular weight of 200,000.

(Preparation of aqueous dispersion of resin (C-8))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-8) of modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-8) by gas chromatography, it was 1% by weight or less with respect to the modified polyolefin resin aqueous dispersion composition (D-8).

[Comparative Example 4: Production of aqueous dispersion of resin (C-9)]
((Meth)acrylic acid ester modification of acid-modified chlorinated polyolefin resin (A-1))
100 parts of acid-modified chlorinated polyolefin resin (A-1) was dissolved in 50 parts of toluene, and 5 parts of an epoxy compound (Eposizer W-131, manufactured by DIC) was added. To this, 5.5 parts of a peroxy ester peroxide (PERBUTYL O, manufactured by NOF CORPORATION) was added at 85° C. in a nitrogen atmosphere. Thereafter, (meth)acrylic acid ester (38.1 parts of cyclohexyl methacrylate, 4.7 parts of 2-hydroxyethyl acrylate) as the monomer group (B) represented by component B-7 in Table 2 ) was added and reacted at 85° C. for 6 hours to obtain a modified polyolefin resin (C-9). The modified polyolefin resin (C-9) had a weight average molecular weight of 210,000.

(Preparation of aqueous dispersion of resin (C-9))
After completion of the reaction, 50 parts of propylene glycol monomethyl ether and 7 parts of 2-amino-2-methyl-1-propanol were added to 100 parts of the reaction solution. With stirring at 90° C., 300 parts of deionized water at 90° C. were added over 60 minutes and the toluene and part of the propylene glycol monomethyl ether were removed under reduced pressure. The mixture was cooled to room temperature with stirring and adjusted to a solid content of 30 wt % with deionized water to obtain an aqueous dispersion composition (D-9) of modified polyolefin resin. As a result of confirming the content of toluene in the aqueous dispersion composition (D-9) by gas chromatography, it was 1% by weight or less with respect to the modified polyolefin resin aqueous dispersion composition (D-9). The modified polyolefin resin aqueous dispersion composition (D-9) was not able to be subjected to a physical property test because it greatly increased in viscosity and solidified one day after preparation.

Table 2 shows the composition ratio of the (meth)acrylic acid ester as the monomer group (B) when the resin (A) is modified.

Abbreviations in Table 2 are listed below.
MMA: methyl methacrylate CHMA: cyclohexyl methacrylate nBMA: n-butyl methacrylate 2MTA: 2-methoxyethyl acrylate HEA: 2-hydroxyethyl acrylate

A test piece was prepared from the prepared aqueous dispersion of the resin, and a hot water resistance test, an adhesion test, and a gasohol resistance test were carried out. The evaluation results are also shown in Tables 3 and 4.

According to the above results, the glass transition temperature Tg of the monomer group (B) is 50 ° C. or higher and 90 ° C. or lower, and the hydroxyl value is 17 mg KOH / g or higher and 50 mg KOH / g or lower, in Examples 1 to 5 It can be seen that the aqueous dispersion containing the modified polyolefin resin has good evaluations in all of hot water resistance, adhesion, and gasohol resistance.

On the other hand, the water-based dispersions containing the modified polyolefin resins according to Comparative Examples 1 and 2, in which the glass transition temperature Tg of the monomer group (B) is less than 50°C, exhibit hot water resistance, adhesion, and resistance. Any evaluation of gasoholity is poor and not suitable for practical use.
Further, the aqueous dispersions containing the modified polyolefin resins according to Comparative Examples 3 and 4, in which the glass transition temperature Tg of the monomer group (B) exceeds 90° C., were evaluated as poor adhesion and gasohol resistance. There is, and it is not suitable for practical use (Comparative Example 3), or because the stability is poor, hot water resistance, adhesion, and gasohol resistance cannot be evaluated, and it is not suitable for practical use (Comparative Example 4).

The aqueous dispersion containing the modified polyolefin resin according to Comparative Example 1, in which the hydroxyl value of the monomer group (B) is less than 17 mgKOH/g, was evaluated for hot water resistance, adhesion, and gasohol resistance. Bad and not suitable for practical use.
The aqueous dispersion containing the modified polyolefin resin according to Comparative Example 4, in which the hydroxyl value of the monomer group (B) exceeds 50 mgKOH/g, has poor stability. Unable to evaluate gasohol properties, not suitable for practical use.

The above results show that when the modified polyolefin resin of the present invention is applied as an aqueous dispersion onto a plastic substrate, a coating film having good adhesion and high resistance to hot water can be obtained.

Claims (5)

A modified product obtained by modifying the resin (A) with the monomer group (B),
The resin (A) is a polyolefin resin or a modified resin thereof,
The monomer group (B) is composed of one or more monomers selected from (meth)acrylic acid and (meth)acrylic acid esters,
The one or more monomers are respectively monomers (1) to monomers (n), the weight ratio of the monomer (n) in the monomer group (B) is Wn, and the monomers Let Tgn(K) be the glass transition temperature of the homopolymer from monomer (n), and Xn (mgKOH/g) be the hydroxyl value of the homopolymer from said monomer (n), where n is 1 or more. Given an integer,
The glass transition temperature Tg of the monomer group (B) calculated from the following formulas (1) and (2) is 50° C. or more and 80 ° C. or less,
A modified polyolefin resin in which the hydroxyl value X of the monomer group (B) calculated from the following formula (3) is 18 mgKOH/g or more and 40 mgKOH/g or less,
An aqueous dispersion, wherein the dispersion medium is water .

Tg (°C) = Tg' + 273.15 (2)

The aqueous dispersion according to claim 1, wherein the modified polyolefin resin has a weight average molecular weight of 10,000 or more and 1,000,000 or less. 3. The aqueous dispersion according to claim 1, wherein the resin (A) is a polyolefin resin modified with carboxylic acid and/or chlorine. Claims 1 to 3, wherein the weight ratio of the resin (A) to the monomer group (B) (resin (A)/monomer group (B)) is 20/80 or more and 95/5 or less. An aqueous dispersion according to any one of claims 1 to 3. A primer comprising the aqueous dispersion according to any one of claims 1-4.