JP6943882B2 - Modified polyolefin resin - Google Patents

Description

The present invention relates to a modified polyolefin resin.

Polyolefin base materials such as polypropylene have excellent performance and are inexpensive, and are therefore widely used in plastic molded parts, various films for food packaging materials, and the like. At that time, the surface of the polyolefin base material is printed or painted for the purpose of protecting the surface and improving the appearance.
However, since the polyolefin base material is a non-polar base material, has a low surface free energy, and has crystallinity, there is a problem that ink or paint is difficult to adhere to the base material. Therefore, a method of improving the adhesion to a polyolefin substrate by adding a chlorinated polyolefin resin to an ink or a paint at the time of printing or painting is widely used.

Such plastic molded products such as polyolefin base materials are often used as members attached to automobile outer panels and members of home appliances and the like. Usually, in order to improve the adhesion between the topcoat coating film and the molded product, a primer containing a chlorinated polyolefin resin or the like is applied to the plastic molded product in advance before the topcoat coating is applied.
Under such circumstances, in recent years, in the painting of an automobile outer panel portion, a method has been proposed in which a plastic molded product is integrated with the automobile outer panel portion and then painted (Patent Document 1). In such a painting method, since the painting line can be unified, it is expected that the amount of paint used will be reduced and the cost will be reduced.

Japanese Unexamined Patent Publication No. 2012-213692

However, in the coating method of Patent Document 1, the primer is applied not only to the plastic molded product but also to the automobile outer panel portion which is a metal. Therefore, when an attempt is made to form a coating film having a certain thickness on the outer panel of an automobile, the topcoat layer is reduced by the amount of the primer layer, and the primer layer is resistant to peeling of the coating film due to pebbles. Since the (chipping resistance) is inferior, there is a problem that the chipping resistance of the entire painted portion is lowered.
Therefore, an object of the present invention is to provide a modified polyolefin resin having excellent chipping resistance.

As a result of diligent research, the present inventors have obtained a copolymer in which a polymer containing a predetermined (meth) acrylic acid ester unit and having a glass transition temperature of 0 ° C. or lower is grafted onto a polyolefin resin or a modified product thereof. It has been found that a certain modified polyolefin-based resin solves the above-mentioned problems. That is, the present invention provides the following.

[1] Component (A): The polyolefin resin or a modified product thereof contains the component (B): the structural unit (i) derived from the (meth) acrylic acid ester represented by the following general formula (I), and the glass transition temperature. A modified polyolefin resin which is a copolymer grafted with a polymer having (Tg) of 0 ° C. or lower.
CH ₂ = C (R ¹ ) COOR ² ... (I)
(In formula (I), R ¹ represents a hydrogen atom or methyl, R ² represents a group represented by −C _n H _{2n + 1} , and n represents an integer of 1 to 18.)
[2] The modified polyolefin resin according to [1], wherein the structural unit (i) has 4 to 12 carbon atoms.
[3] The modified polyolefin resin according to [2], wherein the content of the structural unit (i) in the component (B) is 40% by weight or more and 100% by weight or less.
[4] The modified polyolefin resin according to any one of [1] to [3], wherein the component (A) is a chlorinated polyolefin resin.
[5] The modified polyolefin resin according to any one of [1] to [4], wherein the weight average molecular weight of the component (B) is 1,000 or more and 100,000 or less.
[6] The modified polyolefin resin according to any one of [1] to [5], wherein the hydroxyl value of the component (B) is 5 mgKOH / g or more and 560 mgKOH / g or less.
[7] Any one of [1] to [6], wherein the weight ratio of the component (A) to the component (B) (component (A) / component (B)) is 20/80 or more and 80/20 or less. The modified polyolefin resin according to.
[8] The modified polyolefin resin according to any one of [1] to [7], which has a weight average molecular weight of 10,000 or more and 200,000 or less.
[9] A dispersion composition containing the modified polyolefin resin according to any one of [1] to [8] and a dispersion medium.
[10] A primer containing the modified polyolefin resin according to any one of [1] to [8] or the dispersion composition according to [9].
[11] Component (A): The polyolefin resin or a modified product thereof contains the component (B): the structural unit (i) derived from the (meth) acrylic acid ester represented by the following general formula (I), and the glass transition temperature. A method for producing a modified polyolefin resin, which comprises a step of graft-polymerizing a polymer having (Tg) of 0 ° C. or lower.
CH ₂ = C (R ¹ ) COOR ² ... (I)
(In formula (I), R ¹ represents a hydrogen atom or methyl, R ² represents a group represented by −C _n H _{2n + 1} , and n represents an integer of 1 to 18.)

According to the present invention, it is possible to provide a modified polyolefin-based resin having excellent chipping resistance.

In the present specification, "(meth) acrylic acid" includes methacrylic acid and acrylic acid, and "(meth) acrylate" includes methacrylate and acrylate.

[1. Modified Polyolefin Resin]
The modified polyolefin resin of the present invention is a structural unit (i) derived from a component (A): a polyolefin resin or a modified product thereof, and a component (B): a (meth) acrylic acid ester represented by the above general formula (I). ), And the polymer having a glass transition temperature (Tg) of 0 ° C. or lower is grafted.

[1-1. Ingredient (A)]
The component (A) is a polyolefin resin or a modified product of the polyolefin resin.
[1-1-1. Polyolefin resin]
The polyolefin resin as the component (A) is a polymer of olefins. The polyolefin resin as the component (A) is preferably a polyolefin resin produced by using a Ziegler-Natta catalyst or a metallocene catalyst as a polymerization catalyst, and more preferably a Ziegler-Natta catalyst or a metallocene catalyst as a polymerization catalyst. It is a produced polypropylene or a polyolefin resin obtained by copolymerizing propylene and α-olefin (eg, ethylene, butene, 3-methyl-1-butene, 3-methyl-1-heptene). The polyolefin resin obtained by random copolymerization of propylene and α-olefin may be referred to as a propylene-based random copolymer. Examples of the propylene-based random copolymer include an ethylene-propylene copolymer, a propylene-butene copolymer, an ethylene-propylene-diene copolymer, and an ethylene-propylene-butene copolymer. The polyolefin resin is more preferably a polypropylene or propylene-based random copolymer produced by using a metallocene catalyst as a polymerization catalyst, and particularly preferably polypropylene or ethylene produced by using a metallocene catalyst as a polymerization catalyst. -Propropylene copolymer, propylene-butene copolymer, or ethylene-propylene-butene copolymer. These resins may be used alone or in combination of a plurality of resins.

As the metallocene catalyst described above, known ones can be used. Specific examples of the metallocene catalyst include catalysts obtained by combining the following components (1) and (2) and, if necessary, (3), and the following components (1) and (2). ), And a catalyst obtained by combining (3) as needed is preferable.
-Component (1); A metallocene complex which is a transition metal compound of Group 4 to 6 of the periodic table having at least one conjugated five-membered ring ligand.
-Component (2); ion-exchangeable layered silicate.
-Ingredient (3); organoaluminum compound.

The polyolefin resin synthesized using the metallocene catalyst is preferable as the component (A) because it has features such as a narrow molecular weight distribution, excellent random copolymerizability, a narrow composition distribution, and a wide range of copolymerizable comonomer.

The structure of the polyolefin resin as the component (A) is not particularly limited, and may be any of an isotactic structure, an atactic structure, a syndiotactic structure and the like that can be obtained by a normal polymer compound. Considering the adhesiveness to the polyolefin base material, particularly the adhesiveness at low temperature drying, the polyolefin resin having an isotactic structure polymerized using a metallocene catalyst is preferable as the component (A).

The composition of the polyolefin resin as the component (A) is not particularly limited, but the propylene component of the component (A) is preferably 60 mol% or more, more preferably 70 mol% or more, still more preferably 70 mol% or more. It is preferably 80 mol% or more. When the propylene component of the component (A) is 60 mol% or more, the adhesiveness (adhesiveness) to the propylene substrate becomes better.

[1-1-2. Modified product of polyolefin resin]
The component (A) may be a modified product of a polyolefin resin. Examples of the polyolefin resin and preferable examples of the modified polyolefin resin are described in the above item [1-1-1. Polyolefin resin] has already been described.
The type of modification is not particularly limited, and examples thereof include known modifications such as chlorination; epoxidation; hydroxylation; anhydrous carboxylic oxidation; carboxylic oxidation; and the like. The modified product of the polyolefin resin can be obtained by modifying the polyolefin resin by using a known method. The modified product of the polyolefin resin as the component (A) is preferably a chlorinated polyolefin resin. The method for chlorinating the polyolefin resin will be described later.

When the component (A) is a chlorinated polyolefin resin, the chlorine content of the chlorinated polyolefin resin as the component (A) is preferably 15% by weight or more, more preferably 20% by weight or more. When the chlorine content is 15% by weight or more, the modified polyolefin resin has excellent dispersibility in alcohols such as ethanol and isopropanol. The upper limit of the chlorine content in the chlorinated polyolefin resin as the component (A) is preferably 40% by weight or less, and more preferably 35% by weight or less. When the chlorine content is 40% by weight or less, the modified polyolefin-based resin has excellent adhesion to the polyolefin-based substrate.
The chlorine content of the resin can be measured based on JIS-K7229.
Further, the chlorine content of the component (A) in the modified polyolefin resin of the present invention usually matches the chlorine content of the component (A) as a raw material before being grafted by the component (B).

The modified product as the component (A) may be an acid modified product in which the polyolefin resin is modified with an acid. The acid for modification is not particularly limited, but for example, α, β-unsaturated carboxylic acid and derivatives of α, β-unsaturated carboxylic acid (eg, maleic acid, maleic anhydride, fumaric acid, citraconic acid, etc. Citraconic anhydride, mesaconic acid, itaconic acid, itaconic anhydride, aconitic acid, aconitic anhydride, hymic anhydride, (meth) acrylic acid), and acid anhydrides of α, β-unsaturated carboxylic acid are preferable. Maleic anhydride is more preferred.
As a method for modifying the polyolefin resin with an acid, a known method can be used. For example, a method for melting a polyolefin resin and adding an acid for modifying the polyolefin resin and a radical reaction initiator to obtain an acid-modified polyolefin resin. Can be mentioned. The reaction apparatus is not particularly limited, and for example, a modification reaction may be carried out using an extruder.

The modified product as the component (A) may be a modified product in which the polyolefin resin is modified by a plurality of types of modified materials. Therefore, the modified product as the component (A) is an acid-modified chlorine obtained by modifying a chlorinated polyolefin resin with an acid (for example, an α, β-unsaturated carboxylic acid or a derivative of an α, β-unsaturated carboxylic acid). It may be a modified polyolefin resin.

The component (A) is preferably a chlorinated polyolefin resin or an acid-modified chlorinated polyolefin resin.

[1-1-3. Weight average molecular weight of component (A)]
The weight average molecular weight (Mw) of the component (A) is preferably 5,000 or more. When the weight average molecular weight is 5,000 or more, the cohesive force of the resin is sufficient and the adhesiveness to the substrate is excellent. The upper limit of the weight average molecular weight of the component (A) is preferably 150,000 or less. When the weight average molecular weight is 150,000 or less, the compatibility with other resins contained in the paint or ink is good, and the adhesion to the substrate is good. The weight average molecular weight can be obtained from a standard polystyrene calibration curve by a gel permeation chromatography (GPC) method.
The weight average molecular weight of the component (A) is preferably 5,000 to 150,000.
Here, the weight average molecular weight of the component (A) usually matches the weight average molecular weight measured for the component (A) as a raw material before the component (B) was grafted.

[1-2. Ingredient (B)]
The component (B) is a polymer containing the structural unit (i) derived from the (meth) acrylic acid ester represented by the general formula (I) and having a glass transition temperature (Tg) of 0 ° C. or lower.

[1-2-1. Structural unit (i)]
The component (B) contains a structural unit (i) derived from the (meth) acrylic acid ester represented by the general formula (I).
CH ₂ = C (R ¹ ) COOR ² ... (I)

In the general formula (I), R ¹ represents a hydrogen atom or methyl, R ² represents a group represented by −C _n H _{2n + 1} , and n represents an integer of 1 to 18.
The _{group represented by −C n} H _{2n + 1} may be a linear alkyl group or a branched alkyl group.

Here, the structural unit derived from a certain monomer is a structural unit obtained when a certain monomer is used in a polymerization reaction.

The structural unit (i) preferably has 4 or more carbon atoms, and preferably 12 or less. The structural unit (i) preferably has 4 to 12 carbon atoms. As a result, the chipping resistance of the modified polyolefin resin can be further improved. Here, the number of carbon atoms of the structural unit (i) is usually the same as the number of carbon atoms of the (meth) acrylic acid ester represented by the general formula (I), which is the origin of the structural unit (i).

When the component (B) includes a structural unit (i) having 4 to 12 carbon atoms (hereinafter, _{also referred to as a structural unit (i 4-12 )), the structural unit (i 4- 12} ) in the component (B) is included. _{The content of 12} ) is preferably 40% by weight or more, more preferably 60% by weight or more, and preferably 100% by weight or less. As a result, when the modified polyolefin resin is combined with other components to form a composition (for example, a coating composition), the compatibility with other components becomes good.

The content (%) of the structural unit (i _4-12 ) in the component (B) is represented by the general formula (I) with respect to the total monomer weight used in producing the polymer of the component (B). It usually corresponds to the weight percentage of the monomer which is a (meth) acrylic acid ester and has 4 to 12 carbon atoms.

The structural unit (i) contained in the component (B) may be one type alone or two or more types.

The component (B) may include a structural unit other than the structural unit (i). Examples of the structural unit other than the structural unit (i) that may be contained in the component (B) include a structural unit derived from α, β-unsaturated carboxylic acid (eg, a configuration derived from (meth) acrylic acid). Units) and structural units (eg, (meth) acrylic acid alkyl ester, (meth) acrylic acid hydroxyalkyl ester) derived from α, β-unsaturated carboxylic acid ester other than the structural unit (i).

[1-2-2. Glass transition temperature of component (B)]
The component (B) has a glass transition temperature (Tg) of 0 ° C. or lower, preferably −20 ° C. or lower, more preferably −25 ° C. or lower, and further preferably −30 ° C. or lower. When Tg exceeds 0 ° C., the flexibility of the modified polyolefin resin is lowered, so that the chipping resistance is inferior. Tg is usually −70 ° C. or higher, preferably −65 ° C. or higher, and more preferably −60 ° C. or higher.

The glass transition temperature (Tg) is determined by using the value of each glass transition temperature when each monomer unit constituting the component (B) is homopolymer and the weight ratio of each monomer unit in the component (B). It can be calculated by the following FOX formula. As the Tg of each homopolymer, the Tg described in the Polymer Handbook (Wiley-Interscience Publication, 4th Edition, 1999) and product data can be used.
The weight ratio of each monomer unit in the component (B) is usually the same as the weight ratio (blending ratio) of each monomer to the total weight of the monomers used in producing the polymer of the component (B). do.

<FOX formula> 1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ + W ₃ / Tg ₃ + ... W _n / Tg _n

In the above formula, component (B) and composed of n kinds of monomer units _U 1 ~U _n, monomer unit _U 1 ~U _n each _Tg 1 C. to Tg _n The glass transition temperature of the homopolymer of _Let the weight ratios of the monomer units U _{1 to} Un _{be W 1 to} W _n , respectively. However, the 1 the total weight percentage of the monomer unit _U 1 ~U _n.

As the glass transition temperature of the component (B), the glass transition temperature measured for the polymer of the component (B) as a raw material before being grafted to the component (A) may be used. The glass transition temperature of the component (B) as a raw material can be measured using, for example, a differential scanning calorimeter (eg, “DSC6200R thermal analysis system”, supplied by Seiko Instruments Inc.).
Preferably, the glass transition temperature of the component (B) according to the present invention is the value of each glass transition temperature when each monomer unit constituting the component (B) is a homopolymer and each unit in the component (B). It is a value calculated by the above FOX formula using the weight ratio of the polymer unit.

[1-2-3. Weight average molecular weight of component (B)]
The weight average molecular weight (Mw) of the component (B) is not particularly limited, but is preferably 1,000 or more, more preferably 3,000 or more, preferably 100,000 or less, and more preferably. It is 20,000 or less.
The weight average molecular weight of the component (B) is preferably 1,000 to 100,000, more preferably 3,000 to 20,000.
Here, the weight average molecular weight of the component (B) is usually consistent with the weight average molecular weight measured for the polymer of the component (B) as a raw material before being grafted to the component (A).

[1-2-4. Hydroxy group value of component (B)]
The hydroxyl value of the component (B) is not particularly limited, but is preferably 5 mgKOH / g or more, preferably 560 mgKOH / g or less, more preferably 280 mgKOH / g or less, and further preferably 168 mgKOH / g or less. Is.
When the hydroxyl value of the component (B) is 5 mgKOH / g or more, the compatibility with the other components is good when the modified polyolefin resin is combined with the other components to form a composition (for example, a paint composition). It becomes. When the hydroxyl value of the component (B) is 560 mgKOH / g or less, the polarity of the modified polyolefin resin is appropriate. Therefore, when the modified polyolefin resin is combined with other components to form a composition, other Good compatibility with the components of.
The hydroxyl value of the component (B) is preferably 5 to 560 mgKOH / g, more preferably 5 to 280 mgKOH / g, and even more preferably 5 to 168 mgKOH / g.

Hydroxyl value _{X B} component (B), component (B) n type (n is an integer of 1 or more) is composed of a monomer unit _U 1 ~U _n of the monomer unit _U 1 ~U _n hydroxyl value of a homopolymer of each and _{X 1 ~X n (mgKOH / g} ), the weight ratio of the monomer units _U 1 ~U _n in component (B), respectively and _Y 1 to Y _n (where monomer and the sum of the proportions by weight of the body unit U ₁ ~U _n is 1.), it is calculated from the following equation.
X _B = X ₁ Y ₁ + X ₂ Y ₂ + ... X _n Y _n
The hydroxyl value of the component (B) in the examples is also a value calculated by the above method.

[1-3. Modified Polyolefin Resin]
The modified polyolefin resin of the present invention is a copolymer in which the above component (B) is grafted on the above component (A): polyolefin resin or a modified product thereof.
The modified polyolefin resin of the present invention may be a copolymer in which the component (B) is grafted to the component (A), and after the graft polymerization reaction for grafting the component (B) to the component (A). Further, it may be a copolymer modified with a modifier (for example, with chlorine and / or acid), or may be a copolymer not further modified with a modifier after the graft polymerization reaction.
In the modified polyolefin resin of the present invention, the polymer of the component (B) is grafted onto the component (A). The modified polyolefin resin of the present invention may be a resin produced by grafting a polymer of the component (B) as a raw material onto the component (A) as a raw material by a graft polymerization reaction, and may be used as a raw material. A resin produced by sequentially or simultaneously grafting a monomer for forming a polymer (block) of the component (B) onto the component (A) by a graft polymerization reaction may be used.
The modified polyolefin-based resin of the present invention may be a chlorinated graft-modified polyolefin-based resin, an acid-modified graft-modified polyolefin-based resin, or an acid-modified and chlorinated graft-modified polyolefin-based resin.

The modified polyolefin resin of the present invention is preferably a chlorinated resin. The "chlorinated resin" includes a resin in which the component (A) is chlorinated, a resin in which the component (B) is chlorinated, and a resin in which the components (A) and (B) are chlorinated. NS. The modified polyolefin resin of the present invention is more preferably a chlorinated resin in which the component (A) is chlorinated.

When the modified polyolefin resin is a chlorinated resin, the chlorine content of the modified polyolefin resin is preferably 10% by weight or more, more preferably 15% by weight or more. The upper limit of the chlorine content in the modified polyolefin resin is preferably 35% by weight or less, and more preferably 30% by weight or less.
It is presumed that when the chlorine content of the modified polyolefin resin is within this range, the polarity of the modified polyolefin resin is increased, and the modified polyolefin resin tends to show a linear structure due to the steric repulsion between chlorine atoms. Therefore, it is presumed that it is excellent in dispersibility in highly polar solvents (eg, alcohols).

[1-3-1. Weight average molecular weight of modified polyolefin resin]
The weight average molecular weight of the modified polyolefin resin of the present invention is not particularly limited, but is preferably 10,000 or more, more preferably 30,000 or more, preferably 200,000 or less, and more preferably. It is 150,000 or less.
When the weight average molecular weight of the modified polyolefin resin is 10,000 or more, the adhesiveness is improved. When the weight average molecular weight of the modified polyolefin resin is 200,000 or less, the compatibility with the other components becomes good when the modified polyolefin resin is combined with other components to form a composition.
The weight average molecular weight of the modified polyolefin resin of the present invention is preferably 10,000 to 200,000, more preferably 30,000 to 150,000.

[1-3-2. Content of component (B)]
The content of the component (B) in the modified polyolefin resin of the present invention is not particularly limited, but is preferably 20% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more. be. The upper limit is preferably 80% by weight or less.
The content of the component (B) in the modified polyolefin resin means the weight ratio of the component (B) portion grafted on the component (A) to the modified polyolefin resin.
The weight ratio (%) of the component (B) portion to the modified polyolefin resin usually matches the blending ratio (%) of the component (B) to be graft-polymerized with the component (A) in the production of the modified polyolefin resin (%). However, the total of the compounding weight of the component (A) and the compounding weight of the component (B) is 100%).

[1-3-3. Ingredient (A) / Ingredient (B)]
The weight ratio of the component (A) to the component (B) in the modified polyolefin resin of the present invention is not particularly limited, but is preferably 20/80 or more, more preferably 30/70 or more, and further preferably 30/70 or more. It is 50/50 or more, preferably 80/20 or less.
The weight ratio of the component (A) to the component (B) in the modified polyolefin resin of the present invention is preferably 20/80 or more and 80/20 or less.

[2. Method for manufacturing modified polyolefin resin]
The method for producing a modified polyolefin resin of the present invention is derived from, for example, component (A): a polyolefin resin or a modified product thereof, and component (B): a (meth) acrylic acid ester represented by the above general formula (I). A step of graft-polymerizing a polymer containing the structural unit (i) and having a glass transition temperature (Tg) of 0 ° C. or lower is included. However, in the formula (I), R ¹ represents a hydrogen atom or methyl, R ² represents a group represented by −C _n H _{2n + 1} , and n represents an integer of 1 to 18.
The component (A) and the component (B) are described in the item [1. It is the same as the component (A) and the component (B) described in [Modified polyolefin resin], respectively.
As a method for introducing the component (B) into the component (A) by graft copolymerization, for example, the component (A) as a raw material and the component (B) as a raw material are represented by the above general formula (I) ( Meta) A method for graft-copolymerizing a polymer containing a structural unit (i) derived from an acrylic acid ester and having a glass transition temperature (Tg) of 0 ° C. or lower, a component (A) as a raw material, and a component (B). Examples thereof include a method of graft-copolymerizing a (meth) acrylic acid ester represented by the above general formula (I), which is a raw material for forming the polymer of the above.
When the (meth) acrylic acid ester represented by the general formula (I) is graft-copolymerized with the component (A) as a raw material, the (meth) acrylic acid ester represented by the general formula (I) is used. It may be added sequentially to the component (A) as a raw material, or may be added all at once. Further, a monomer other than the (meth) acrylic acid ester represented by the general formula (I) may be added to the component (A) as a raw material.

The conditions for graft polymerization are not particularly limited, and known methods such as a melting method and a solution method may be followed. The melting method has the advantages that the operation is simple and the reaction can be performed in a short time. When the solution method is used, a uniform graft polymer with few side reactions can be obtained.

In the case of the melting method, the component (A) is heated and melted (heated and melted) in the presence of a radical reaction initiator to react with the component (B). The component (B) may be in the form of a monomer before polymerization or in the form of a polymer after polymerization. The temperature for heating and melting may be at least the melting point of the component (A), and is preferably at least the melting point of the component (A) and at least 300 ° C. Equipment such as a Banbury mixer, kneader, and extruder can be used for heating and melting.

In the case of the solution method, the component (A) is dissolved in an organic solvent and then reacted with the component (B) by heating and stirring in the presence of a radical reaction initiator. The component (B) may be in the form of a monomer before polymerization or in the form of a polymer after polymerization.
As the organic solvent, it is preferable to use an aromatic hydrocarbon solvent such as toluene or xylene. The temperature during the reaction is preferably 100 to 180 ° C.

The radical reaction initiator used in the melting method and the solution method is not particularly limited, and examples thereof include organic peroxide compounds and azonitriles. Examples of the organic radical compound include di-tert-butyl peroxide, dicumyl peroxide, tert-butyl cumyl peroxide, benzoyl peroxide, dilauryl peroxide, 2,5-dimethyl-2,5-. Di (tert-butylperoxy) hexane, cumene hydroperoxide, tert-butylhydroperoxide, 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 Examples thereof include -2-ethylhexanoate, tert-butylperoxyisopropyl carbonate, cumylperoxyoctate and the like, and those having an appropriate half-life temperature depending on the temperature at which radical polymerization is carried out may be selected.

In the method for producing a modified polyolefin resin of the present invention, the component (A) may be graft-polymerized in the form of a composition containing an arbitrary stabilizer in addition to the component (A).
Optional stabilizers include, for example, epoxy compounds; metal soaps such as calcium stearate and lead stearate used as stabilizers for polyvinyl chloride resins; organic metal compounds such as dibutyltin dilaurate and dibutylmalate. Examples include hydrotalcite compounds. The epoxy compound is not particularly limited, but an epoxy compound that can be compatible with a resin that has undergone modification such as chlorination is preferable. Examples of the epoxy compound include compounds having an epoxy equal amount of about 100 to 500 and having one or more epoxy groups per molecule, and examples of such epoxy compounds include vegetable oils having natural unsaturated groups. Is epoxidized with a peracid such as peracetic acid to obtain epoxidized vegetable oil (epoxidized soybean oil, epoxidized linseed oil, etc.); unsaturated fatty acids such as oleic acid, tall oil fatty acid, soybean oil fatty acid, etc. are epoxidized. Epoxidized fatty acid esters; epoxidized alicyclic compounds such as epoxidized tetrahydrophthalate; obtained by condensing bisphenol A or polyhydric alcohol with epichlorohydrin, for example, bisphenol A glycidyl ether, ethylene glycol glycidyl ether, propylene glycol glycidyl. Ethers such as ethers, glycerol polyglycidyl ethers, sorbitol polyglycidyl ethers; and butyl glycidyl ethers, 2-ethylhexyl glycidyl ethers, decyl glycidyl ethers, stearyl glycidyl ethers, allyl glycidyl ethers, phenyl glycidyl ethers, sec-butyl phenyl glycidyl ethers. , Tart-Butylphenyl glycidyl ether, monoepoxide compounds typified by phenol polyethylene oxide glycidyl ether and the like; The stabilizer may be used alone or in combination of two or more. When the component (A) is graft-polymerized in the form of a composition containing a stabilizer, the weight ratio of the stabilizer to the component (A) is preferably 1 to 20% by weight (in terms of solid content).

The method for producing a modified polyolefin resin of the present invention may include any step in addition to the above-mentioned steps.
An optional step includes, for example, a step of graft-polymerizing the component (B) with the component (A) to obtain a graft-modified polyolefin resin, and then further modifying the graft-modified polyolefin resin. The type of modification is not particularly limited, and examples thereof include known modifications such as chlorination; epoxidation; hydroxylation; anhydrous carboxylic oxidation; carboxylic oxidation; and the like.
These modifications can be carried out by known methods.
For example, when the modified polyolefin resin is a chlorinated resin, the production method of the present invention may include a step of chlorinating the resin at any stage of the production, for example, chlorinating the polyolefin resin. The step of chlorinating the graft-modified polyolefin-based resin obtained after graft-polymerizing the component (B) on the polyolefin resin may be included.
Therefore, as a production method for obtaining a modified polyolefin resin which is a chlorinated resin, for example, a method of grafting the component (B) onto the component (A) and then chlorinating it, or a method of chlorinating the polyolefin resin to obtain the component (A). A method of grafting the component (B) to the component (A) after obtaining the chlorinated polyolefin resin as is mentioned.

As the chlorination method, a known method can be used and is not particularly limited, and examples thereof include a method of dissolving a resin in a chlorination solvent such as chloroform and then blowing chlorine gas to introduce chlorine. More specifically, chlorination disperses or dissolves the resin in a medium such as water, carbon tetrachloride, or chloroform, and at 50-140 ° C. under pressure or normal pressure in the presence of a catalyst or irradiation with ultraviolet light. This can be done by blowing chlorine gas in the temperature range.

When a chlorinated solvent is used in the production of the chlorinated resin, the chlorinated solvent used can usually be distilled off by reducing the pressure or the like, or can be replaced with another organic solvent.

When the polyolefin resin is chlorinated to obtain the chlorinated polyolefin resin as the component (A), the chlorine content of the chlorinated polyolefin resin as the component (A) is preferably 15% by weight or more, more preferably 20% by weight. That is all. When the chlorine content is 15% by weight or more, the obtained modified polyolefin resin has excellent dispersibility in alcohols such as ethanol and isopropanol. The upper limit of the chlorine content in the chlorinated polyolefin resin as the component (A) is preferably 40% by weight or less, and more preferably 35% by weight or less. When the chlorine content is 40% by weight or less, the obtained modified polyolefin-based resin has excellent adhesion to the polyolefin-based substrate.

[3. Modified Polyolefin Resin Composition]
The modified polyolefin-based resin of the present invention may form a modified polyolefin-based resin composition together with any other component. Optional components include, for example, stabilizers for suppressing chlorine withdrawal. The stabilizer is not particularly limited, but for example, an epoxy compound; metal soaps such as calcium stearate and lead stearate used as a stabilizer for polyvinyl chloride resin; and organic metals such as dibutyltin dilaurate and dibutylmalate. Compounds; Examples thereof include hydrotalcite compounds, preferably epoxy compounds. The epoxy compound is not particularly limited, but for example, the above [2. Method for Producing Modified Polyolefin Resin], an epoxy compound exemplified as an arbitrary stabilizer that can be contained in the composition of the component (A) can be mentioned, and an epoxy compound compatible with the modified polyolefin resin modified with chlorine can be mentioned. preferable. As the stabilizer, only one of these may be used, or two or more thereof may be used in combination.
Further, for example, the modified polyolefin-based resin composition may be in the form of a dispersion composition containing the modified polyolefin-based resin and the dispersion medium. In the present specification, the "dispersion medium" contains a solvent capable of dissolving the modified polyolefin resin, and the "dispersion composition" may be a solution of the modified polyolefin resin composition.

Examples of the dispersion medium include aromatic hydrocarbons such as toluene and xylene; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; aliphatic hydrocarbons such as hexane, heptane and octane; and acetone, methyl ethyl ketone and methyl isobutyl ketone. Ketones; esters such as methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate; alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol; ethylene glycol, Glycols such as ethyl cellosolve and butyl cellosolve; water and the like can be mentioned.
The dispersion medium may be one type alone or a combination of two or more types.

[4. Applications of modified polyolefin resins]
The modified polyolefin resin of the present invention can be used as an adhesive for metals and / or resins, a primer, a binder for paints, and a binder for inks. In particular, the modified polyolefin resin of the present invention has good adhesion and excellent chipping resistance, and is therefore useful as a binder for automobile paints and a primer for automobile paints.

Next, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. "Parts" and "%" mean "parts by weight" and "% by weight", respectively, unless otherwise noted. The following operations were performed in the air at normal temperature and pressure unless otherwise specified.

<Production Example A1> Biaxial extrusion of a propylene-based random copolymer (propylene unit content: 80% by weight, ethylene unit content 20% by weight) produced using a polyolefin resin metallocene catalyst as a polymerization catalyst at a barrel temperature of 350 ° C. It was supplied to the machine and heat-reduced to obtain a polypropylene-based resin (A1) having a weight average molecular weight of 5,000.

<Production Example A2> Same as Production Example A1 except that a propylene-based random copolymer produced using a polyolefin resin metallocene catalyst as a polymerization catalyst (propylene unit content: 90% by weight, ethylene unit content: 10% by weight) was used. A polypropylene resin (A2) having a weight average molecular weight of 111,000 was obtained.

<Production Example A3> Same as Production Example A1 except that a propylene-based random copolymer produced using a polyolefin resin metallocene catalyst as a polymerization catalyst (propylene unit content: 94% by weight, ethylene unit content 6% by weight) was used. A polypropylene resin (A3) having a weight average molecular weight of 100,000 was obtained.

<Production Example A4> A propylene-based random copolymer produced using a polyolefin resin metallocene catalyst as a polymerization catalyst (propylene unit content: 90% by weight, ethylene unit content 5% by weight, butene unit content 5% by weight) was used. A polypropylene resin (A4) having a weight average molecular weight of 45,000 was obtained in the same manner as in Production Example A1 except for the above.

<Production Example A5> Biaxial extrusion of a propylene-based random copolymer (propylene unit content: 80% by weight, ethylene unit content 20% by weight) produced using a polyolefin resin metallocene catalyst as a polymerization catalyst at a barrel temperature of 400 ° C. It was supplied to the machine and heat-reduced to obtain a polypropylene-based resin (A5) having a weight average molecular weight of 2,000.

<Production Example CL1> Chlorinated Polyolefin Resin 100 parts by weight of the polypropylene-based resin (A1) obtained in Production Example A1 was put into a glass-lined reaction kettle. Chloroform was added thereto, and chlorine gas and oxygen gas were blown in while irradiating with ultraviolet rays under a pressure of ^{2 kg / cm 2, and chlorine was chlorinated until the chlorine content became 32 wt%.} After completion of the reaction, 6 parts by weight of an epoxy compound (Eposizer W-100EL, manufactured by Dainippon Ink and Chemicals Co., Ltd.) was added as a stabilizer and supplied to an extruder with a vent equipped with a suction part for solvent removal on the screw shaft part. Then, the solvent was removed and solidified to obtain a chlorinated polypropylene resin (A1CL1) having a weight average molecular weight of 5000, which is a chlorinated polyolefin resin.

<Production Example CL2> Chlorinated Polyolefin Resin A chlorinated polypropylene resin (A5CL2) having a weight average molecular weight of 2,000 in the same manner as Production Example CL1 except that the polypropylene resin (A5) obtained in Production Example A5 was used. Got

<Production Example CL3> Chlorinated Polyolefin Resin A chlorinated polypropylene resin (A4CL3) having a weight average molecular weight of 50,000 in the same manner as in Production Example CL1 except that the polypropylene resin (A4) obtained in Production Example A4 was used. Got

<Production Example M1> Acid-Modified Polyolefin Resin 100 parts by weight of the polypropylene resin (A3) obtained in Production Example A3 is placed in a three-necked flask equipped with a stirrer, a dropping funnel, and a cooling tube for refluxing a monomer, and placed at 180 ° C. Completely dissolved in the oil bath. After nitrogen substitution in the flask was performed for about 10 minutes, 4 parts by weight of maleic anhydride was added over about 5 minutes with stirring, and then 0.4 part by weight of di-tert-butyl peroxide was added by 1 part by weight of heptane. It was dissolved in a portion and charged over about 30 minutes from the dropping funnel. Then, the inside of the system was kept at 180 ° C., and the reaction was continued for another hour. Then, the unreacted maleic anhydride was removed over about 1 hour while depressurizing the inside of the flask with an aspirator, and acid modification having a weight average molecular weight of 105,000. A polyolefin resin (A3M1) was obtained.

<Manufacturing Example MCL1> Acid-modified chlorinated polyolefin resin (acid-modified)
100 parts by weight of the polypropylene resin (A2) obtained in Production Example A2, 4 parts by weight of maleic anhydride, and 2 parts by weight of di-t-butyl peroxide are uniformly mixed, and a twin-screw extruder (L / D) is used. = 60, φ = 15 mm, 1st barrel to 14th barrel). Dwelling time is 10 minutes, rotation speed is 200 rpm, barrel temperature is 100 ° C (1st and 2nd barrel), 200 ° C (3rd to 8th barrel, 90 ° C (9th and 10th barrel), 110 ° C (11th to 14th barrel). ), And the unreacted maleic anhydride was removed by performing a reduced pressure treatment to obtain a maleic anhydride-modified polypropylene resin (A2M2).

(Chlorination)
100 parts by weight of the obtained maleic anhydride-modified polypropylene resin (A2M2) was put into a glass-lined reaction kettle. Chloroform was added thereto, and chlorine gas and oxygen gas were blown in while irradiating with ultraviolet rays under a pressure of ^{2 kg / cm 2, and chlorine was chlorinated until the chlorine content became 32 wt%.} After completion of the reaction, 6 parts by weight of an epoxy compound (Eposizer W-100EL, manufactured by Dainippon Ink and Chemicals Co., Ltd.) was added as a stabilizer and supplied to a vented extruder equipped with a suction part for solvent removal on the screw shaft part. Then, the solvent was removed and solidified to obtain an acid-modified chlorinated polypropylene resin (A2M2CL1) having a weight average molecular weight of 143,000, which is a chlorinated polyolefin resin.

<Production Example MCL2> Acid-modified chlorinated polyolefin resin An acid-modified chlorinated polypropylene resin having a weight average molecular weight of 5,000 is the same as that of Production Example MCL1 except that the polypropylene-based resin A1 obtained in Production Example A1 is used. (A1M2CL2) was obtained.

<Production Example MCL3> Acid-modified chlorinated polyolefin resin An acid-modified chlorinated polypropylene resin having a weight average molecular weight of 110,000 is the same as that of Production Example MCL1 except that the polypropylene-based resin A3 obtained in Production Example A3 is used. (A3M2CL3) was obtained.

<Production Example MCL4> Acid-Modified Chlorinated Polyolefin Resin An acid-modified polyolefin resin (A4M1) was obtained in the same manner as in Production Example M1 except that the polypropylene-based resin A4 obtained in Production Example A4 was used. Next, chlorination was carried out in the same manner as in Production Example CL1 except that the obtained acid-modified polyolefin resin (A4M1) was used to obtain an acid-modified chlorinated polypropylene resin (A4M1CL4) having a weight average molecular weight of 75,000. rice field.

<Example 1>
(Manufacturing of acrylic polymer (B1))
Examples of Table 2 after adding 2.8 parts by weight of a peroxyester-based peroxide (Niper BMT-K40, manufactured by Nippon Oil & Fats Co., Ltd.) to 233 parts of toluene heated to 85 ° C. in a nitrogen atmosphere. A total of 100 parts by weight of each acrylic monomer was added at the blending ratio described in 1, and the reaction was carried out at 85 ° C. for 6 hours or more, then cooled, and the acrylic weight at a glass transition temperature of −66 ° C. A coalescence (B1) was obtained.

(Manufacturing of modified polyolefin resin)
Production Example 80 parts of the chlorinated polypropylene resin (A1CL1) as the component (A) obtained in CL1 and 20 parts of the acrylic polymer (B1) as the component (B) are heated to 70 ° C. in a nitrogen atmosphere. After adding to 233 parts of the toluene, the reaction was carried out at 70 ° C. for 4 hours, and after cooling, 1 part by weight of an epoxy compound (Eposizer W-100EL, manufactured by Dainippon Ink and Chemicals Co., Ltd.) was added as a stabilizer. , A toluene dispersion containing the modified polyolefin resin (C1) was obtained.

<Example 2>
Acrylic weight at a glass transition temperature of −33 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 2 in Table 2. A coalescence (B2) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 50 parts of the acid-modified chlorinated polypropylene resin (A2M2CL1) obtained in Production Example MCL1 was used, and instead of 20 parts of the acrylic polymer (B1), acrylic weight was used. A toluene dispersion containing the modified polyolefin resin (C2) was obtained in the same manner as in Example 1 except that 50 parts of the coalescence (B2) was used.

<Example 3>
Acrylic weight at a glass transition temperature of -1 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 3 of Table 2. A coalescence (B3) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 20 parts of the acid-modified chlorinated polypropylene resin (A1M2CL2) obtained in Production Example MCL2 was used, and instead of 20 parts of the acrylic polymer (B1), acrylic weight was used. A toluene dispersion containing the modified polyolefin resin (C3) was obtained in the same manner as in Example 1 except that 80 parts of the coalesced (B3) was used.

<Example 4>
Acrylic weight at a glass transition temperature of −55 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 4 of Table 2. A coalescence (B4) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 70 parts of the acid-modified chlorinated polypropylene resin (A3M2CL3) obtained in Production Example MCL3 was used, and instead of 20 parts of the acrylic polymer (B1), acrylic weight was used. A toluene dispersion containing the modified polyolefin resin (C4) was obtained in the same manner as in Example 1 except that 30 parts of the coalescence (B4) was used.

<Example 5>
Acrylic weight at a glass transition temperature of −46 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 5 of Table 2. A coalescence (B5) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 60 parts of the acid-modified chlorinated polypropylene resin (A4M1CL4) obtained in Production Example MCL4 was used, and instead of 20 parts of the acrylic polymer (B1), acrylic weight was used. A toluene dispersion containing the modified polyolefin resin (C5) was obtained in the same manner as in Example 1 except that 40 parts of the coalescence (B5) was used.

<Example 6>
Acrylic weight at a glass transition temperature of −43 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 6 of Table 2. A coalescence (B6) was obtained.
Except that the chlorinated polypropylene resin (A4CL3) obtained in Production Example CL3 was used instead of the chlorinated polypropylene resin (A1CL1), and the acrylic polymer (B6) was used instead of the acrylic polymer (B1). Obtained a toluene dispersion containing a modified polyolefin resin (C6) in the same manner as in Example 1.

<Example 7>
Acrylic weight at a glass transition temperature of -60 ° C. A coalescence (B7) was obtained.
A modified polyolefin resin in the same manner as in Example 1 except that 60 parts of the chlorinated polypropylene resin (A1CL1) was used and 40 parts of the acrylic polymer (B7) was used instead of 20 parts of the acrylic polymer (B1). A toluene dispersion containing (C7) was obtained.

<Example 8>
Acrylic weight at a glass transition temperature of −66 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 8 of Table 2. A coalescence (B8) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 70 parts of the chlorinated polypropylene resin (A5CL2) obtained in Production Example CL2 was used, and instead of 20 parts of the acrylic polymer (B1), an acrylic polymer (Acrylic polymer) ( B8) A toluene dispersion containing the modified polyolefin resin (C8) was obtained in the same manner as in Example 1 except that 30 parts were used.

<Example 9>
Acrylic weight at a glass transition temperature of −24 ° C., similar to the production of the acrylic polymer (B1) described in Example 1, except that each acrylic monomer was added at the blending ratio shown in Example 9 in Table 2. A coalescence (B9) was obtained.
A modified polyolefin resin (A1CL1) was used in the same manner as in Example 1 except that 50 parts of the chlorinated polypropylene resin (A1CL1) was used and 50 parts of the acrylic polymer (B9) was used instead of 20 parts of the acrylic polymer (B1). A toluene dispersion containing C8) was obtained.

<Example 10>
Acrylic weight at a glass transition temperature of −66 ° C. was the same as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Example 10 in Table 2. A coalescence (B10) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 60 parts of the acid-modified polypropylene resin (A3M1) obtained in Production Example M1 was used, and instead of 20 parts of the acrylic polymer (B1), an acrylic polymer (B10) was used. A toluene dispersion containing the modified polyolefin resin (C10) was obtained in the same manner as in Example 1 except that 40 parts were used.

<Comparative example 1>
An acrylic polymer having a glass transition temperature of 27 ° C. was produced in the same manner as in the production of the acrylic polymer (B1) described in Example 1 except that each acrylic monomer was added at the blending ratio shown in Comparative Example 1 in Table 2. (B11) was obtained.
Instead of 80 parts of the chlorinated polypropylene resin (A1CL1), 50 parts of the acid-modified chlorinated polypropylene resin (A3M2CL3) obtained in Production Example MCL3 was used, and instead of 20 parts of the acrylic polymer (B1), an acrylic polymer was used. A toluene dispersion containing the modified polyolefin resin (C10) was obtained in the same manner as in Example 1 except that 50 parts of (B11) was used.

<Evaluation>
The modified polyolefin resins obtained in Examples and Comparative Examples were evaluated by the following methods. The results are shown in Table 3.

<Weight average molecular weight (Mw)>
It was measured by GPC according to the following conditions.
Equipment: HLC-8320GPC (supplied by Tosoh Corporation)
Columns: TSK-gel G-6000 H × L, G-5000 H × L, G-4000 H × L, G-3000 H × L, G-2000 H × L (supplied by Tosoh Corporation)
Eluent: THF
Flow rate: 1 mL / min
Temperature: Pump oven, column oven 40 ℃
Injection volume: 100 μL
Standard substance: Polystyrene EasiCal PS-1 (supplied by Agilent Technologies)

<Glass transition temperature (Tg)>
Each glass transition temperature when each monomer used in producing the known polymer of component (B) is homopolymer, and the composition of each monomer used in producing component (B). Using the ratio, it was calculated by the above-mentioned FOX formula.

<Hydroxy group value (mgKOH / g) of component (B) (acrylic polymer)>
The hydroxyl value when each monomer used in producing the polymer of the known component (B) is homopolymer, and the blending ratio of each monomer used in producing the component (B) are shown. It was calculated by the method described above.

<Stability of resin dispersion>
The properties of the toluene dispersion liquid containing the modified polyolefin resin obtained in Examples and Comparative Examples were visually evaluated according to the following criteria immediately after the production and one week after the production. If it is good, it can be used.
Best: No separation of the dispersion was observed immediately after production and after 1 week, and the solution properties were good.
Good: After 1 week, the separation of the dispersion can be visually confirmed, or the dispersion is turbid, but the dispersion immediately after production does not show separation.
Defective: Separation of the dispersion is observed both immediately after production and after 1 week.

<Paint stability>
The toluene dispersion of the modified polypropylene resin obtained in Examples and Comparative Examples was mixed with toluene to prepare a toluene dispersion having a solid content of 20%. 15 parts by weight of the prepared toluene dispersion (solid content 20 wt%) was added to 90 parts by weight of urethane resin (Hitachi Kasei Kogyo Co., Ltd. solid content 30 wt%), stirred for 10 minutes with a shaker, and allowed to stand at room temperature for 1 day. The properties of the solution after placement were observed, and the paint stability (compatibility of the compounded resin) was visually judged from the separated state of the solution.
A: No thickening or separation of the solution was observed, and the solution properties were good.
B: The solution thickens slightly, but no separation is observed.
C: Although there is no separation of the components, fine particles are confirmed in the solution.
D: Separation of components can be visually confirmed.

<Preparation of test piece>
The dispersions obtained in Examples and Comparative Examples were adjusted to a solid content concentration of 30% by weight, coated on a polypropylene base material, dried at 80 ° C. for 5 minutes, then coated with a two-component urethane paint, and 30 at 80 ° C. Each test was carried out after drying for a minute to prepare a test piece (painted plate).

<Adhesion test>
Linear notches reaching the base material were made vertically and horizontally in the coating film of the coating plate at 1 mm intervals to make 100 sections (grinds), and cellophane adhesive tape was adhered on it and peeled off in the 180 ° direction. .. The operation of bringing the cellophane adhesive tape into close contact and peeling it off was performed 10 times for the same 100 sections, and the adhesiveness (adhesiveness) was evaluated according to the following criteria. If the number of peeled coating film sections is 50 or less, there is no practical problem.
(Evaluation criteria for adhesion)
A: There is no peeling of the coating film.
B: The number of sections of the peeled coating film is 1 or more and 10 or less.
C: The number of sections of the peeled coating film is more than 10 and 50 or less.
D: There are more than 50 sections of the peeled coating film.

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

<Chipping resistance test>
Cool the coated plate in a low temperature room cooled to -20 ° C, and fix the test plate vertically to the test plate mounting part of the stepping stone tester (Suga Test Instruments Co., Ltd., JA-400 type) so that the angle is 90 ° from the horizontal. Then, 100 g of No. 7 crushed stone was sprayed at an air pressure of 5 kgf / cm ^{2 in 5 seconds to scratch the test plate.} After that, the coated plate is washed with water and dried, the cellophane adhesive tape is adhered to the coated surface, the tape is peeled off by holding one end of the tape, the coating film raised by chipping is removed, and the degree of peeling scratches is evaluated according to the following criteria. bottom. The peeling scratches were evaluated within a frame of 70 mm in length × 70 mm in width of the impacted portion.
A: Best. The peeling area ratio per evaluation area is 0.0% or more and less than 0.7%.
B: Good. The peeling area ratio per evaluation area is 0.7% or more and less than 1.2%.
C: Inferior. The peeling area ratio per evaluation area is 1.2% or more and less than 3.5%.
D: The worst. The peeling area ratio per evaluation area is 3.5% or more.

In the item "resin skeleton" of Table 1, "P" represents propylene, "E" represents ethylene, and "B" butadiene represents "B" butadiene.

In Table 2, "2EHA" is 2-ethylhexyl acrylate, "HEA" is 2-hydroxyethyl acrylate, "BA" is butyl acrylate, "INA" is isononyl acrylate, "AA" is acrylate, and "LMA". "" Represents lauryl methacrylate, "LA" represents lauryl acrylate, "HEMA" represents 2-hydroxyethyl methacrylate, and "EA" represents ethyl acrylate.
The ratio of C _4-12 is the weight percentage (%) of the (meth) acrylic acid ester having 4 to 12 carbon atoms and represented by the general formula (I) with respect to the total weight of the blended monomers. be.

According to Table 3, it can be seen that the modified polyolefin resin of Example is excellent in chipping resistance as compared with Comparative Example 1. Further, it can be seen that the modified polyolefin resin of the example has no problem in adhesion to polypropylene which is a non-polar substrate and stability when used as a resin dispersion or a paint.

Claims (9)

Component (A): Polyolefin resin or modified product thereof contains component (B): two or more structural units (i) derived from (meth) acrylic acid ester represented by the following general formula (I) and glass transition. Ri copolymer der the polymer temperature (Tg) of 0 ℃ or less is grafted,
Number of carbon atoms of R ² comprises a structural unit which is 4~12 _{(i 4-12),}
The content of the structural unit (i _4-12 ) in the component (B) is 40% by weight or more and 90% by weight or less.
Modified polyolefin resin.
CH ₂ = C (R ¹ ) COOR ² ... (I)
(In formula (I), R ¹ represents a hydrogen atom or methyl, R ² represents a group represented by −C _n H _{2n + 1} , and n represents an integer of 1 to 18.) The modified polyolefin resin according to claim 1 , wherein the component (A) is a chlorinated polyolefin resin. The modified polyolefin resin according to claim 1 or 2 , wherein the weight average molecular weight of the component (B) is 1,000 or more and 100,000 or less. The modified polyolefin resin according to any one of claims 1 to 3 , wherein the hydroxyl value of the component (B) is 5 mgKOH / g or more and 560 mgKOH / g or less. The modified polyolefin according to any one of claims 1 to 4 , wherein the weight ratio of the component (A) to the component (B) (component (A) / component (B)) is 20/80 or more and 80/20 or less. System resin. The modified polyolefin resin according to any one of claims 1 to 5 , wherein the weight average molecular weight is 10,000 or more and 200,000 or less. A dispersion composition containing the modified polyolefin resin according to any one of claims 1 to 6 and a dispersion medium. A primer comprising the modified polyolefin resin according to any one of claims 1 to 6 or the dispersion composition according to claim 7. Component (A): Polyolefin resin or modified product thereof contains component (B): two or more structural units (i) derived from (meth) acrylic acid ester represented by the following general formula (I) and glass transition. the temperature (Tg) of 0 ℃ or less polymer containing a structural unit number of carbon atoms of ^{R 2} is 4 to 12 _{(i 4-12),} the number of constituent carbon atoms of ^{R 2} is from 4 to 12 A method for producing a modified polyolefin resin, which comprises a step of graft polymerization so that the content of the unit (i _4-12 ) is 40% by weight or more and 90% by weight or less.
CH ₂ = C (R ¹ ) COOR ² ... (I)
(In formula (I), R ¹ represents a hydrogen atom or methyl, R ² represents a group represented by −C _n H _{2n + 1} , and n represents an integer of 1 to 18.)