JPH0488026A - Aqueous dispersion - Google Patents

Abstract

PURPOSE:To obtain an aqueous dispersion having excellent adhesiveness with a resin molded article, etc., and good workability by dispersing in water a chlorinated modified polyolefin obtained by subjecting a specific polyolefin to graft copolymerization with a specific alpha,beta-vinyl monomer and further chlorinating the resultant polymer. CONSTITUTION:The aimed aqueous dispersion obtained by dispersing 5-70 pts.wt. chlorinated modified polyolefin obtained by subjecting a polyolefin consisting essentially of propylene and/or 1-butene and having >=dl/g (preferably 1.5-7dl/g) intrinsic viscosity to graft copolymerization with alpha,beta-vinyl monomer (preferably 2-hydroxypropyl acrylate) having OH to provide a modified polymer having 0.4-1dl/g (preferably 0.5-1dl/g) intrinsic viscosity and further chlorinating the polymer and having 10-40wt.% (preferably 15-35wt.%) chlorine content in 95-30 pts.wt. water.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an aqueous dispersion, and in particular can be used as an undercoat to various resin molded products to improve the adhesion of paint to the surface of the molded product. The present invention relates to an aqueous dispersion suitable as a brimer that can maintain a good working environment because it does not contain an organic solvent.

<Prior Art> Conventionally, the added value of polyolefin molded products such as polypropylene has been increased by painting the surface or forming other resin layers. However, polyolefins generally have poor polarity and poor adhesion to common paints and other resins. Therefore, in the past, the surface of the molded product was coated with chromic acid, flame, corona discharge, plasma, etc.
Attempts have been made to improve the adhesion of paints by increasing the polarity of the surface by treating it with a solvent or the like. However, these treatments have disadvantages in that they require complicated treatments and are dangerous due to the use of corrosive chemicals. Another disadvantage is that strict process control is required in order to obtain stable processing effects.

Therefore, as an effective means to improve these defects, there is a method of coating the surface of molded products etc. with brimer.
As the primer, various surface treatment agents have been proposed, which are made by further chlorinating polypropylene graft-modified with a compound containing a specific carboxyl group.

(Japanese Patent Publication No. 50-10916, Japanese Patent Publication No. 55-149
(No. 304, Japanese Unexamined Patent Publication No. 6,110,8608) <Problems to be Solved by the Invention> However, these conventional surface treatment agents contain insoluble matter, do not have sufficient adhesiveness and heat resistance, Furthermore, since it has poor solubility in solvents, when applied as an undercoat, a coating film with sufficient smoothness cannot be obtained, resulting in disadvantages such as deterioration of the appearance of molded products, especially gloss. Furthermore, these conventional surface treatment agents all contain organic solvents or are used after being dissolved in organic solvents, but this organic solvent has the problem of deteriorating the working environment during manufacturing and use. There is. Therefore, in recent years, there has been a demand for surface treatment agents that do not contain organic solvents in order to reduce the amount of volatile organic solvents used and maintain a good working environment in factories.

Therefore, the object of the present invention is to improve the adhesion of resin molded products to molded products made of various resins such as polyolefins such as polypropylene, synthetic rubber, unsaturated polyesters, epoxy resins, polyurethane resins, and composite resins thereof. Because it has excellent properties, it can be applied to the surface of these molded products to obtain a coating film with sufficient peel strength and adhesion, and since it is water-based and does not contain organic solvents, it is easy to maintain a good working environment. An object of the present invention is to provide an aqueous dispersion suitable as a brimer.

<Means for Solving the Problems> In order to solve the above problems, the present invention provides a polyolefin containing propylene and/or 1-butene as a main component and having an intrinsic viscosity [η of 1 dl/g or more], in which a hydroxyl group is added. A modified polymer obtained by graft copolymerizing α,β-vinyl monomers having an intrinsic viscosity of 0.4 to 1 dI2/
The present invention provides an aqueous dispersion in which a chlorinated modified polyolefin having a chlorine content of 10 to 40% by weight, obtained by further chlorinating the modified polymer (g), is dispersed in water.

Further, the α,β-vinyl monomer having a hydroxyl group has 1
It is preferable that it is at least one selected from mono(meth)acrylic esters of alcohols and mono(meth)acrylic esters of polyhydric alcohols.

Hereinafter, the aqueous dispersion of the present invention will be explained in detail.

The chlorinated modified polyolefin, which is the main component of the aqueous dispersion of the present invention, is obtained by further chlorinating a modified polymer obtained by graft copolymerizing a polyolefin with an α,β-vinyl monomer having a hydroxyl group. . The polyolefin that is the main component of this chlorinated modified polyolefin is mainly composed of propylene and/or 1-butene, and includes, for example, a homopolymer of propylene, a homopolymer of 1-butene, and a mixture of propylene and 1-butene. Copolymers of butene or propylene and/or 1-butene with other α
- It is a copolymer with an olefin. In this polyolefin, the propylene content is usually 90 mol%
That's about it. In addition, other α-olefins include, for example, ethylene, 1-pentene, 1-hexene, 1
-octene, 1-decene, 4-methyl-1-pentene and the like. In the present invention, one or more of these other a-olefins may be contained in the polyolefin. Polyolefin is other a-
When containing an olefin, its content is usually 40 mol% or less, preferably 30 mol% or less.

The intrinsic viscosity [η] of this polyolefin is such that an aqueous dispersion can be obtained that has high cohesive force and can maintain a good appearance even after being applied to a molded product and heat treated.
] is 1dj2/g or more, preferably 1 to 10dff/g
, particularly preferably 1.5 to 76127 g.

Here, the intrinsic viscosity [η] in the present invention is 135°C
This is the value obtained by measuring in decalin. Such a polyolefin preferably has a crystallinity of 5% or more as determined by X-ray diffraction.

In the present invention, in order to obtain a modified polymer, the α,β-vinyl monomer having a hydroxyl group (hereinafter simply referred to as "vinyl monomer") to be graft copolymerized to the above-mentioned polyolefin is as follows: For example, hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)
Acrylate, 3-chloro-2-hydroxypropyl (
(meth)acrylic acid ester of monohydric alcohol such as meth)acrylate, glycerin mono(meth)acrylate, pentaerythritol mono(meth)acrylate,
trimethylolpropane mono(meth)acrylate,
Mono(meth)acrylic esters of polyhydric alcohols such as tetraethylolethane mono(meth)acrylate, butanediol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate; 10 undecen-1-ol, 1-octene- Examples include 3-ol, 2-methanol norbornene, hydroxystyrene, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, N-methylol acrylamide, 2-(meth)acryloyloxyethyl acid phosphate, glycerin monoallyl ether, allyl alcohol, allyloxyethanol, etc. It will be done. Each of these alone has 2
It can also be used in combination of more than one species. Among these vinyl monomers, (meth)acrylic esters of monohydric alcohols and acrylic esters of polyhydric alcohols are particularly preferred, and 2-hydroxypropyl acrylate is particularly preferred.

In the present invention, this modified polymer has a high cohesive force and has an intrinsic viscosity [η] of is 0.4-1d, i2/g, preferably 05-1d/g
belongs to.

The modified polymer as described above can be produced according to various known methods. For example, it can be carried out by graft copolymerizing the vinyl monomer onto the polyolefin in the presence of a radical polymerization initiator and in the presence or absence of an inert solvent.

As a method for graft copolymerization in the presence of an inert solvent, for example, a polyolefin is dissolved in an inert solvent to prepare a solution, a vinyl monomer and a radical polymerization initiator are added to this solution, and the mixture is heated with stirring. A method in which powdered polyolefin is impregnated with a solution of vinyl monomer and a radical polymerization initiator dissolved in an inert solvent, and then heated to a temperature at which the powder does not dissolve to react. Examples include.

At this time, the ratio of radical polymerization initiator/vinyl monomer used is usually in a molar ratio of 1/100 to 315, preferably 1/20 to 1/2. Also, the reaction is
It is preferable to carry out the reaction under heating and stirring. The reaction method may be either a batch method or a continuous method, but a batch method is preferable in order to perform the graft copolymerization uniformly.

In addition, as a method of performing graft copolymerization in the absence of an inert solvent, for example, a method of heating and melting a polyolefin, adding a vinyl monomer and a radical polymerization initiator, and reacting while stirring: a polyolefin, Examples include a method in which a vinyl monomer and a radical polymerization initiator are mixed in advance, the mixture is heated and melted in an extruder, and graft copolymerized while being extruded.

In methods carried out in the absence of these inert solvents,
The amounts of the vinyl monomer and the radical polymerization initiator used, and the proportions of the two used, are the same as in the method carried out in the presence of an inert solvent.

Examples of the radical polymerization initiator used in the graft copolymerization include benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-t
-butylperoxide, 2,5-dimethyl-2,5-di(peroxybenzoate)hexyne-3,1,4-bis(t-butylperoxyisopropyl)benzene, lauroylperoxide, 25-dimethyl-2,5-di(
Organic peroxides such as t-butylperoxy)-hexyne-3,2,5-dimethyl-25-di(t-butylperoxy)-hexane; t-butylperacetate, t-
Organic bersesters such as butylberbenzoate, t-butylperphenylacetate, t-butylberisobutyrate, t-butylber-5ec-octoate, t-butylberpivalate, cumylberbivalate, t-butylperdiethyl acetate, Examples include azo compounds such as azobisisobutyronitrile and dimethylazoisobutyronitrile. Among these, organic peroxides and organic peresters are preferred, especially dicumyl peroxide, dialkyl peroxide, 25-dimethyl-2,5-di(t-butylperoxy)hexyne-3
, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, and 1,4-bis(t-butylperoxyisopropyl)benzene.

When using an organic solvent, the reaction temperature is usually 80 to 2
About 50°C, usually 150°C when using an extruder
It may be in the range of ~350°C.

The reaction time is about 0.5 to 6 hours.

When using an organic solvent, specific examples of the organic solvent include aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as hexane, heptane, octane, and decane; trichlorethylene, perchlorethylene,
Examples include halogenated hydrocarbons such as dichloroethylene and chlorobenzene. Among these, aromatic hydrocarbons are preferred, and alkyl group-substituted aromatic hydrocarbons are particularly preferred.

The aqueous dispersion of the present invention has as a main component a chlorinated modified polyolefin obtained by further chlorinating the modified polymer obtained as described above. This chlorinated modified polyolefin is easy to dissolve in a solvent, makes it easy to produce an aqueous dispersion by the solvent replacement method described later, and has good adhesion to polypropylene molded products, since the chlorine content is 1.
0 to 40% by weight, preferably 15 to 35% by weight. Further, the intrinsic viscosity of this chlorinated modified polyolefin is usually 0.1 to 1 dβ/g, preferably 0.3 to 1 dβ/g.
It is about 0.8 dρ/g, and the crystallinity is about 0 to 20%.

This chlorinated modified polyolefin can be produced by dissolving or dispersing the modified polymer in a suitable organic solvent and then reacting it with chlorine gas. This reaction is usually carried out at a temperature of about 50 to 120°C and about 0.5 to 5
It is common to do this by time. In addition, in order to make the reaction proceed efficiently, we may irradiate it with ultraviolet rays or visible light.
Alternatively, a radical polymerization initiator may be used.

Examples of organic solvents used include aliphatic hydrocarbons such as hexane, heptane, octane, decane, dodecane, and tetradodecane; alicyclic hydrocarbons such as methylcyclobencune, cyclohexane, methylcyclohexane, cyclooctane, and cyclododecane. Aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, ethyltoluene, trimedelbenzene, diisobutylbenzene, chlorobenzene, bromobenzene, 0-dichlorobenzene, carbon tetrachloride, carbon tetrabromide, chloroform, Examples include halogenated hydrocarbons such as bromoform, trichloroethane, trichloroethane, tetrachloroethane, and tetrachloroethylene. These may be used alone or in combination of two or more.

The aqueous dispersion of the present invention is obtained by dispersing the chlorinated modified polyolefin obtained as described above in water. Examples of the method for producing the aqueous dispersion of the present invention by dispersing the chlorinated modified polyolefin in water include a drum emulsification method in which the chlorinated modified polyolefin, water, and a surfactant are mixed all at once and emulsified: A pulverization method in which pre-pulverized chlorinated modified polyolefin is poured into water with a surfactant and dispersed; after mixing the chlorinated modified polyolefin dissolved in an organic solvent with a surfactant and water, the organic solvent is removed. Examples include a solvent substitution method in which dispersion is carried out using a homomixer, a homomixer method in which dispersion is carried out using a homomixer, and a phase inversion method, which are appropriately selected depending on the physical properties of the chlorinated modified polyolefin used.

As the surfactants used, mention may be made of nonionic and anionic surfactants. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkylamine ether, and the like.
Examples of the anionic surfactant include fatty acid salts, higher alcohol sulfates, sodium alkylbenzenesulfonates, naphthalenesulfonic acid formalin condensates, polyoxyethylene alkyl ether sulfates, and sodium alkylbenzenesulfonates are particularly preferred.

The amount of this surfactant to be used is usually 0.0% relative to the chlorinated modified polyolefin, so that the dispersion state of the chlorinated modified polyolefin is good and the resulting aqueous dispersion has good adhesion to the molded product. .05 to 10% by weight is preferred;
Particularly preferred is 0.1 to 7% by weight. In addition, when the aqueous dispersion of the present invention is applied to the surface of a molded article by spray coating, uneven coating does not occur on the coated surface, there is no variation in coating film adhesion, and the coating film is smooth after coating. It is preferable to use the surfactant in an amount of 3 to 45% by weight based on the chlorinated modified polyolefin in terms of good properties.

The blending ratio of chlorinated modified polyolefin and water in the aqueous dispersion of the present invention is 5 to 70% of chlorinated modified polyolefin.
The ratio is appropriately selected within the range of 95 to 30 parts by weight of water. In particular, when spraying the aqueous dispersion of the present invention, uneven coating will occur on the coated surface. Therefore, for example, the content of chlorinated modified polyolefin should be 3 to 45% by weight in order to improve the smoothness of the coated film when used as a brimer.
Preferably by weight.

In addition, the aqueous dispersion of the present invention may contain a thickener,
Basic substances, antifoaming agents, etc. can also be added. Furthermore, in order to improve the wettability with the material to be coated, a small amount of organic solvent may be added as necessary.

Examples of thickeners include mineral thickeners such as ammonium alginate, sodium alginate, bentonite clay, and acrylic acid thickeners such as sodium polyacrylate, ammonium polyacrylate, and crosslinked acrylic emulsion copolymers: Examples include cellulose derivatives such as carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, and hydroxyethylcellulose, with carboxymethylcellulose being particularly preferred.

Examples of antifoaming agents include vegetable oils such as castor oil, soybean oil and linseed oil, mineral oils such as spindle oil and liquid paraffin, fatty acid nioleyl alcohols such as stearic acid and oleic acid, polyoxyalkylene glycols, octyl alcohol, etc. Alcohols: Fatty acid esters such as ethylene glycol distearate and polyoxyethylene sorbitan monolaurate: Phosphate esters such as tributyl phosphate and sodium octyl bosphate; Amides such as polyoxyalkylene amide, aluminum stearate, oleic acid Examples include metal soaps such as potassium and calcium stearate; silicones such as dimedyl silicone and polyether-modified silicone; and amines such as cyamylamine and polyoxypropylene alkylamine.

Furthermore, in addition to the above, the aqueous dispersion of the present invention may optionally contain various stabilizers such as antioxidants, weathering stabilizers, and heat resistant inhibitors; coloring agents such as titanium oxide, organic pigments; carbon black, ferrite, etc. It may also contain a conductivity imparting agent.

The aqueous dispersion of the present invention can be applied to the surface of a molded article made of polyolefin or other polymer and used as a brimer or the like to improve the adhesion of paint to the surface. In particular, the aqueous dispersion of the present invention includes, for example, high-pressure polyethylene, medium-low pressure polyethylene, polypropylene, poly-4-methyl-1-pentene, poly-1-butene,
It can be suitably used for molded articles made of polyolefins such as borisdylene, olefin copolymers such as ethylene/propylene copolymers, ethylene/butene copolymers, and propylene/butene copolymers.

Furthermore, in addition to the above-mentioned polyolefins and their copolymers, the aqueous dispersion of the present invention can also be made of molded products made of polypropylene and synthetic rubber, polyamide resins, unsaturated polyester resins, polybutylene terephthalate resins, polycarbonate resins, etc. It can also be used for surface treatment of molded products such as automobile bumpers, and furthermore, steel plates and steel plates for electrodeposition treatment. In addition, undercoat the surface coated with paints, primers, adhesives, etc. whose main components are polyurethane resin, fatty acid-modified polyester resin, oil-free polyester resin, melamine resin, epoxy resin, etc. to improve the adhesion of the paint, etc. to the surface. It is also used to improve the image quality and form coating films with excellent image clarity and low-temperature impact resistance.

In addition, the molded product to which the aqueous dispersion of the present invention is applied may be formed by molding the various polymers or resins described above by any of the known molding methods such as injection molding, compression molding, blow molding, extrusion molding, and rotary molding. It may be molded.

The aqueous dispersion of the present invention can be applied to molded products containing inorganic fillers such as curcum, zinc white, glass fiber, titanium white, magnesium sulfate, and pigments, especially when the coating film is A brimer coating film with good adhesion can be formed.

Moreover, the molded article coated with the aqueous dispersion of the present invention may contain various stabilizers, ultraviolet absorbers, hydrochloric acid absorbers, etc. in addition to the above.

Preferably used stabilizers include, for example, 2,6-
Di-t-butyl-4-methylphenol, tetrakis [
Methylene (3,5-di-t-pudyl-4-hydroxyhydrocinnamate)]methane, metaoctadecyl-3-(
4'Hydoxy-35-di-t-butylphenyl)propionate, 2,2'-methylenebis(4-methyl-6-
t-butylphenol), 4,4'-butylidene bis(
3-methyl-6t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 2
．． 2-thiobis(4-methyl-6-t-butylphenol), 1.3 5-1-lyntyl 2.4.6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1. 3. Phenol stabilizers such as 5-tris(2-methyl-4-hydroxy-5-t-butylphenol)butane; Sulfur stabilizers such as dilaurylthiodipropionate and distearylthiodipropionate;
Examples include phosphorus stabilizers such as tridecyl phosphite and trinonylphenyl phosphite.

Further, as the ultraviolet absorber used, for example, 2-
Hydroxy-4-octoxybenzophenone, 2-ethylhexyl-2-cyano 3,3-diphenylacrylate, para-octylphenyl thalidylate, and the like.

Examples of the hydrochloric acid absorbent include calcium stearate.

A suitable method for applying the aqueous dispersion of the present invention to the surface of a molded article is spray coating, for example, by spraying it onto the surface of the molded article using a spray gun. The coating on the molded article may be carried out at room temperature, and after the coating is applied, it is dried by an appropriate method such as natural drying or forced drying under heat to form a coating film.

As described above, after the aqueous dispersion of the present invention is applied to the surface of a molded article and dried, the surface of the molded article is coated with paint by electrostatic coating, spray painting, brush coating, etc. can be applied. The paint may be applied by applying an undercoat and then a topcoat. After the paint is applied, the paint film is cured according to a conventional method of heating with nichrome wire, infrared rays, high frequency waves, etc., and a molded article having the desired paint film on the surface can be obtained. The method for curing the coating film is appropriately selected depending on the material and shape of the molded article, the properties of the paint used, etc.

In addition, the aqueous dispersion of the present invention can be applied to a wide range of applications in addition to the above-mentioned applications as a brimer for molded products, taking advantage of its excellent adhesion, peel strength, and water resistance. Of course, it can also be used as an additive for adhesives and paints.

<Examples> Hereinafter, the present invention will be specifically explained with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited to these Examples in any way.

Further, in the following, the physical properties of the coating film were evaluated according to the following method.

A test piece with a base mark was prepared according to the method for the base mark test described in JD S K5400, and a cellotape made by Chiban ■, trade name) was attached to the base of the test piece. After pasting it on the eye, it was immediately pulled in the 90' direction to peel it off, and the number of base lines that were not peeled off out of 100 base lines was counted and used as an index of adhesion.

Card plate crushing 1 Prepare a coating film on the base material, make a 1 cm wide cut with a cutter blade until the blade reaches the base material, and after peeling off the edges,
The edge of the peeled coating film is 50 mm at a speed of 7 minutes.
The peel strength was measured by pulling the coating in the 0° direction until it peeled off.

After immersing the Suiyu test piece in water at 40°C for 240 hours, it is subjected to a substrate test to evaluate adhesion.

(Example 1) 250 parts by weight of polypropylene (intrinsic viscosity [η]: 2.Od°C/g) and 500 parts by weight of toluene were placed in a 1.5°C reaction vessel equipped with a stirring device, and heated while stirring. The temperature was raised to 150°C. After 25 parts by weight of 2-hydroxypropyl acrylate and 5 parts by weight of di-t-butyl peroxide were each added dropwise in portions over 5 hours, the reaction was further carried out at 150'C for 2 hours with stirring, resulting in graft modification. Polypropylene was obtained.

When the content of 2-hydroxypropyl acrylate in the obtained graft-modified polypropylene was measured, it was found to be 1.
It was 6% by weight. In addition, the intrinsic viscosity [η] is 135
When measured in °C decalin, it was 0.7 dj2/g.

The graft-modified polypropylene obtained above was heated to 110'C in a chlorobenzene solvent to completely dissolve it, and while maintaining the temperature, light was completely blocked and chlorine gas was supplied to react for about 2 hours. I let it happen. A large excess of methanol was added to the resulting reaction mixture to precipitate a reaction product, which was separated in a furnace, washed repeatedly with methanol, and then dried under reduced pressure to obtain graft-modified chlorinated polypropylene.

The chlorine content of the obtained graft-modified and chlorinated polypropylene was measured and found to be 30% by weight.

Next, the obtained graft-modified chlorinated polypropylene was dissolved in toluene to prepare a solution having a polymer concentration of 125 g/f2. 500g of this polymer solution, 50g of distilled water
0 g and 1.44 g of sodium dodecylbenzenesulfonate (Neoperex F-25, manufactured by Kao Corporation) were mixed by stirring at a rotation speed of 1.0000 rpm for 15 minutes.

Next, 0.72 g of polyacrylic acid (Wako Tsumugi Yakuhin, Hibiswako-304) was added, stirred, and mixed to obtain an emulsion. Toluene in the obtained emulsion was distilled off under reduced pressure using an evaporator, and the polymer An aqueous dispersion having a concentration of 20% by weight was obtained.

This aqueous dispersion was applied by spraying to a square plate made of polypropylene (X440, manufactured by Mitsui Petrochemical Industries, Ltd.) which had been washed with 1,1,1-trichloroethane vapor at a weight of 200 g/m2.

After drying this square plate by heating at 100''C for 30 minutes in an air oven, it was subjected to a base grain test, peel strength measurement, and water resistance evaluation. The results are shown in Table 1.

(Example 2) In the same manner as in Example 1, after applying the water dispersion to a polypropylene square plate, a urethane paint (manufactured by Nippon B Chemical ■, R-271) was further coated to a dry film thickness of 60 μm. did. Next, baking was performed in an oven at 100'C for 30 minutes to obtain a coating sample.

The obtained sample was subjected to a base grain test, peel strength measurement, and water resistance evaluation. The results are shown in Table 1.

(Example 3) Painting was carried out in the same manner as in Example 2, except that a poly-4-methylbentene-1 (manufactured by Mitsui Petrochemical Industries, Ltd., TPX) square plate was used instead of the polypropylene square plate.
The obtained coating film sample was subjected to a base grain test, peel strength measurement, and water resistance evaluation. The results are shown in Table 1.

(Example 4) Instead of 2-hydroxypropyl acrylate-1, 2
A graft-modified polypropylene was produced in the same manner as in Example 1 except that -hydroxyethyl methacrylate was used. 2- of the obtained graft-modified polypropylene
The content of hydroxyethyl methacrylate was measured and found to be 11% by weight. Also, 135 in Decalin
When the intrinsic viscosity [η] was measured at °C, it was 0.7 d,
c/g. This graft-modified polypropylene was chlorinated in the same manner as in Example 1, and then an aqueous dispersion was prepared. Samples were prepared in the same manner as in Example 2, and the base grain test, peel strength measurement, and water resistance evaluation were carried out. Served. The results are shown in Table 1.

(Example 5) 3 kg of the same polypropylene used in Example 1,
2-hydroxypropyl acrylate) 120g and 2
,5-dimethyldi(t-butylperoxy)hexane 1
After pre-mixing 2 g with a Henschel mixer, the mixture was supplied to a twin-screw extruder (manufactured by Ikegai Iron Works, PCM=45), extruded and reacted while kneading at a heating temperature of 210°C and a rotation speed of 26 Orpm. Modified polypropylene was obtained.

When the content of 2-hydroxypropyl acrylate in the obtained graft-modified polypropylene was measured, it was found to be 1
．． It was 5% by weight. Also, in decalin at 135°C
The intrinsic viscosity measured was 0.5 dβ/g.
This graft-modified polypropylene was chlorinated in the same manner as in Example 1, and then an aqueous dispersion was prepared, and samples were prepared in the same manner as in Example 2 and used for the base grain test, peel strength measurement, and water resistance evaluation. provided. The results are shown in Table 1.

(Comparative Example 1) The same polypropylene square plate used in Example 1 was coated with a topcoat in the same manner as in Example 2 without applying the water dispersion to prepare a sample, and this was used as the base material. It was used for testing, peel strength measurement, and water resistance evaluation.
The results are shown in Table 1.

(Comparative Example 2) An aqueous dispersion was prepared in the same manner as in Example 1, except that 2-hydroxypropyl acrylate was not used and it was not graft copolymerized with polypropylene. Samples were prepared in the same manner, and subjected to a base grain test, peel strength measurement, and water resistance evaluation. The results are shown in Table 1.

Peeling strength: g/cm Base size Number of base lines that were not peeled off per 100 base areas <Effects of the invention> The aqueous dispersion of the present invention can be applied to resin molded products, for example, polyolefins such as polypropylene, synthetic rubber, unsaturated It has excellent adhesion to molded products made of various resins such as polyester, epoxy resin, polyurethane resin, etc., or composite resins of these, so it has sufficient peel strength and adhesion when applied to the surface of these molded products. It is suitable as a brimer because it can form a coating film, and since it is aqueous and does not contain organic solvents, it can maintain a good working environment.

Claims (2)

[Claims] (1) A modified polymer made by graft copolymerizing an α,β-vinyl monomer having a hydroxyl group to a polyolefin mainly composed of propylene and/or 1-butene and having an intrinsic viscosity [η] of 1 dl/g or more. coalescence, and the intrinsic viscosity is 0
．． An aqueous dispersion obtained by dispersing in water a chlorinated modified polyolefin having a chlorine content of 10 to 40% by weight, which is obtained by further chlorinating a modified polymer having a chlorine content of 4 to 1 dl/g. (2) The α,β-vinyl monomer having a hydroxyl group has 1
The aqueous dispersion according to claim 1, which is at least one selected from mono(meth)acrylic esters of alcohols and mono(meth)acrylic esters of polyhydric alcohols.