JPS62270637A - Primer composition - Google Patents

Abstract

PURPOSE:To obtain a primer composition which strengthens the adhesive force of a paint or an adhesive to a surface of a synthetic rubber, polyolefin resin, vinyl chloride or the like, by mixing a chlorinated polyolefin with a specified hydroxyl group-containing hydrocarbon polymer in an organic solvent. CONSTITUTION:This primer composition comprises (a) a chlorinated polyolefin or chlorinated polyethylenevinyl acetate copolymer, (b) a hydrocarbon polymer which has at least one hydroxyl group on a molecular terminal and whose main chain is saturated or partially saturated and (c) an organic solvent. As the chlorinated polyolefin and the chlorinated polyethylene/vinyl acetate copoly mer (a), those having a degree of chlorination of about 3-80% are used. As component (b), a polyhydroxy polyolefin of an average MW of 1,000-5,000 is preferable.

Description

[Detailed description of the invention] 3. Detailed description of the invention Purpose of the invention (industrial application field) The present invention is applicable to various synthetic rubbers including polyolefin vulcanized rubber, polyolefin synthetic resins, vinyl chloride, etc. This invention relates to a primer composition that is used as an undercoat to strengthen the adhesion of paints and adhesives on the surfaces of various synthetic resins.

(Prior art) There are many types of industrial rubber products, especially ethylene-propylene-diene ternary copolymer rubber (EPDM).
Polyolefin vulcanized rubbers such as ethylene-propylene copolymer rubber (EPM) have excellent weather resistance, aging resistance, ozone resistance, etc., and can also be used in a wide range of temperatures from -50°C to 150°C. Because it is a rubber with excellent features such as , it is now used in many fields. In addition, depending on the application, the above EPDM or EPM
Natural rubber (NR), styrene-butadiene, copolymer rubber (SBR), butadiene rubber (BR), isobutylene-isoprene copolymer rubber (IIR), chloroprene rubber (cR), acrylonitrile-butadiene copolymer rubber (NBR), etc. Rubbers blended with synthetic rubbers, or rubbers blended with resins such as ABS resin, styrene resin (PS), polyethylene (PE), and polypropylene (PP) are also used in many fields.

In addition, similar to polyolefin vulcanized rubber, polyolefin-based synthetic resins such as PP and PE have excellent weather resistance, aging resistance, ozone resistance, etc., and are also inexpensive, making them suitable for various vehicle parts. It is used in a wide range of applications, including electronic products and appliances.

(Problems to be Solved by the Invention) However, polyolefin vulcanized rubbers such as EPDM and EPM, and polyolefin synthetic resins such as PP and PR, do not contain polar groups in the main chain of their molecules, so they are reactive. There is a problem in that even if a paint or adhesive is applied to the surface of a molded product made from these rubbers or resins, the resulting coating film is likely to peel off.

However, although many countermeasures have been attempted to address the above-mentioned problems, no satisfactory solution has yet been found.

In addition, when molded products are made from resins that contain large amounts of plasticizer, such as vinyl chloride resin, the plasticizer migrates to the surface of the molded product over long periods of use, so paints applied to the surface and There is a problem that the adhesive strength of the adhesive gradually decreases.

As a result of repeated research in view of the above problems, the present inventor has discovered a primer composition that has strong adhesion to polyolefin vulcanized rubber, polyolefin synthetic resin, vinyl chloride resin, etc., and has achieved the present invention. It has been reached.

Structure of the Invention (Means for Solving Problems) That is, the present invention comprises (al) a chlorinated polyolefin or a chlorinated polyethylene-vinyl acetate copolymer, and (bl) a main chain having at least one hydroxyl group at the end of the molecule. The above problems are solved by employing a primer composition comprising a mixture of a saturated or partially saturated hydrocarbon polymer and (c) an aqueous solvent.

(Function) Since the primer composition having the above structure has strong adhesion to polyolefin vulcanized rubber, polyolefin synthetic resin, or vinyl chloride resin, it can be used as an undercoat. The adhesion of paints and adhesives applied to the surface of molded products made of polyolefin vulcanized rubber, polyolefin synthetic resin, vinyl chloride resin, etc. is significantly improved.

(Example) Hereinafter, the constituent components of the primer composition of the present invention will be explained by giving specific examples.

(a) First, chlorinated polyolefin is chlorinated polyethylene or chlorinated polypropylene, both of which are amorphous polymers with a chlorination degree of 3 to 80%, preferably 10 to 50%.

All of these polymers have excellent properties such as weather resistance, ozone resistance, and chemical resistance, and are resistant to polar polymers as well as non-polar polymers such as polyolefin vulcanized rubber and polyolefin synthetic resins. Polymers also exhibit high adhesion, but those with a degree of chlorination of 3% or less or 80% or more have poor adhesion.

Also, what is chlorinated polyethylene-vinyl acetate copolymer?
It is a polymer obtained by radical copolymerization of chlorinated polyethylene and vinyl acetate, and is used unvulcanized.

The chlorinated polyethylene in this polymer has a chlorination degree of 3.
The amount of vinyl acetate is 80% to 80%, preferably 10 to 50%, and the amount of vinyl acetate is about 10 to 35% by weight based on the chlorinated polyethylene.

Like the chlorinated polyolefin mentioned above, this polymer also has excellent properties such as weather resistance, ozone resistance, and chemical resistance. It is a polymer that also shows high adhesion to.

(g)) As a hydrocarbon polymer with a saturated or partially saturated main chain containing a hydroxyl group at the end of the molecule, polyhydroxypolyolefin with an average molecular weight of 11,000 to 5,000 (manufactured by Mitsubishi Chemical Industries, Ltd., product name "Polytail") -H
", "Polytail-HA"), or a monomer containing one or more hydroxyl groups, preferably 1.8 to 5.0 hydroxyl groups in one molecule, and whose main chain is saturated or partially saturated and has an average molecular weight of 500. ~50,000, preferably 1,000 to 20,000 polyhydroxy polybutadiene polymers
142695).

Since all of the above-mentioned hydrocarbon polymers contain hydroxyl groups in their molecules, they are characterized in that compositions with various properties can be obtained by utilizing the reactivity of these hydroxyl groups.

Therefore, by mixing the above-mentioned chlorinated polyolefin or chlorinated polyethylene-vinyl acetate copolymer with the above-mentioned hydrocarbon polymer in an organic solvent, a primer composition having strong adhesion to various polymers can be obtained. You can get things.

The appropriate mixing ratio is 1 to 90 parts by weight of the hydrocarbon polymer to 100 parts by weight of the chlorinated polyolefin or chlorinated polyethylene-vinyl acetate copolymer.

(c) Next, the organic solvent used during mixing is n-
Saturated hydrocarbons such as hexane, cyclohexane, ethylcyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene; dioxane, tetrahydrofuran,
Ethers such as; acetate esters such as ethyl acetate and propyl acetate; ketones such as acetone, cyclohexanone, ethylcyclohexanone, and methyl ethyl ketone;
Examples include solvents appropriately selected from chlorinated hydrocarbons such as trichlorethylene, tetrachlorethylene, and methylchloroform, or mixed solvents consisting of two or more thereof.

Next, the above primer composition is applied to various synthetic resins such as PP, PE and vinyl chloride, or polyolefin vulcanized rubber such as EPDM and EPM, and furthermore, the properties of polyolefin vulcanized rubber are The above NR, SB'R, I IRXCR, N in an amount within a range that will not be lost.
Rubber components such as BR, ABS resin, PSSPE, PP,
Also included are those containing resin components such as ethylene-vinyl acetate copolymer resin (EVA).

In addition, the above-mentioned polyolefin-based vulcanized rubber and those to which the above-mentioned various rubber components and resin components are added include compounds that are usually used, namely: 1, ■ 2-mercaptohenzothiazole, zinc dimethyldithiocarbamate, tetramethylthiuram disulfide as a vulcanization accelerator, ■ Phenyl-α-naphthylamine, 2゜6-T as an anti-aging agent, antioxidant, and ozone deterioration inhibitor. -butyl-p-cresol, (1) carbon blank, magnesium carbonate, clay as a filler, (2) dioctyl sebacate, mineral oil, etc. as a plasticizer are added.

No special equipment is required to apply the primer composition, and it is sufficient to simply apply the primer composition using a conventional coating method such as dipping, spraying, or brushing.

Further, since the above primer composition is a one-component type and has a very long pot life, if the viscosity increases due to evaporation of the solvent, the viscosity can be adjusted by adding the solvent again.

[Example-1] Chlorinated polyethylene-vinyl acetate copolymer (hereinafter referred to as C1
-EVA) and a polyhydroxypolyolefin with an average molecular weight of 11,000 to 5,000 having a hydroxyl group at the end of the molecule ("Polytail-H" or "Polytail-H")
AJ) in toluene to prepare primer compositions having the formulations shown in Tables 1 to 9 below. (Hereinafter, all parts in the table are parts by weight.) Table-1 (Primer composition-1) Table-2 (Primer composition-2) Table-3 (Primer composition-3) Table-4 ( Primer composition-4) Table-5 (Primer composition-5) Table-6 (Primer composition-6) Table-7 (Primer composition-7) Table-8 (Primer composition-8) Table-9 ( Primer Composition-9) Table-10 (Comparative Example-1) Table-11 (Comparative Example-2) Next, in order to examine the adhesion of the above primer compositions-1 to 9, tests were conducted using the following method. .

A rubber compound having the composition shown in Table 12 was vulcanized at 160°C for 30 minutes to produce a base material made of EPDM with a thickness of 100 cm, and this was cut into 10011 x 10 Q mm squares to form two test pieces. Created.

Next, as shown in the figure, the primer composition 1 shown in Table 1 was applied to each end of each side of the two test pieces 3, and the primer composition 1 was air-dried at room temperature for 30 minutes to form a primer layer 1.

Next, a chloroprene rubber adhesive 2 having the composition shown in Table 13 was applied to the surface of the primer layer 1, and after air drying at room temperature for 30 minutes, both test pieces 1 were bonded and left at room temperature. I left it for 24 hours.

Thereafter, this test piece I was pulled in the direction of the arrow in the figure to measure its tensile shear strength, and the results shown in Table 14 were obtained.

In addition, primer compositions-2 to 9 and the above-mentioned Table-10,
Primer composition having the composition shown in 11 (Comparative Examples-1 to 2)
Table 14 also shows the results of a similar tensile shear test using .

Table 14 As a result, the tensile shear strength of the test pieces using primer compositions 1 to 9 was extremely high. In addition,
In the primer compositions of Comparative Examples 1 and 2, the degree of chlorination of CJ-EVA was inappropriate, so the tensile shear strength decreased.

Next, each of the compositions of Comparative Examples 3 to 11 below has been conventionally used as an undercoat for polyolefin vulcanized rubber and polyolefin synthetic resin.

Comparative Example-3 "Ester Resin-20" (manufactured by Toyobo Co., Ltd., saturated polyester resin) was mixed with methyl ethyl ketone/toluene = 1/9
A primer composition was prepared by diluting with a mixed solvent consisting of:

Comparative Example 4 A primer composition was prepared by diluting Vinyrite-VMCHJ (union carbide, vinyl chloride vinyl acetate copolymer resin) with a mixed solvent consisting of methyl ethyl ketone/toluene = 1/1.

Comparative Example-5 A primer composition was prepared by diluting "Esresoku BM-2" (manufactured by Block Chemical Co., Ltd., butyral resin) with a mixed solvent consisting of butanol/xylene = 1/1.

Comparative Example-6 “Orestar M2S 80AJ (manufactured by Mitsui Toatsu,
A primer composition was prepared by diluting a moisture-curable polyurethane resin with toluene.

Comparative Example-7 A mixture consisting of ``Desmophen-1004 (manufactured by Bayer, polyhydroxy compound) / ``Desmodur-R'' (manufactured by Bayer, polyisocyanate) = 1/1.5 was mixed with methylene glycol / butyl acetate / toluene = 1/1/1
A primer composition was prepared by diluting with a mixed solvent consisting of:

Comparative Example 8 A primer composition was prepared by diluting Beccosol J-534j (manufactured by Dainippon Ink & Chemicals, a linseed oil-modified long oil alkyd resin) and cobalt naphthenate (drying agent) with a mineral base.

Comparative Example-9 "Pesocozole J-524J (Tenhi, manufactured by T Ink Chemical Industries, Ltd., linseed oil modified long oil alkyd resin) / [Super Beckamine J-100J (manufactured by Dainippon Ink Chemical Industries, Ltd., butylated melamine resin)" A primer composition was prepared by diluting a mixture of 4/1 with xylene.

Comparative Example-10 “Acryloid C-110VJ (manufactured by Rohm & Haas, thermoplastic acrylic resin)/Nitrocellulose = 99
A primer composition was prepared by diluting a mixture of 1/1 with toluene.

Comparative Example-11 Acrydic 47-712j (Dainippon Ink & Chemicals, thermosetting acrylic resin) / [Super Beckamine 47-508J (Dainippon Ink & Chemicals, butylated melamine resin) = 4/ A primer composition was prepared by diluting a mixture of 1 with 2 volumes of a mixture of toluene/butyl acetate=1/1.

Therefore, these compositions were applied as an undercoat to the test pieces made of EPDM, and a chloroprene rubber adhesive having the composition shown in Table 13 was applied thereon to bond the test pieces together. The tensile shear strength was measured by the method.

As a result, the tensile shear strengths of test pieces using these primers were all extremely low. (1,0
kg/cnl or less) [Example-2] Next, chlorinated polyethylene (hereinafter abbreviated as C1-PE) and the above "Polytail-H" or "Polytail-H"
AJ and AJ were mixed in toluene to prepare primer compositions having the formulations shown in Tables 15 to 23 below.

Table-16 (Primer composition-11) Table-17 (Primer composition-12) Table-18 (Primer composition-13) Table-19 (Primer composition-14) Table-20 (Primer composition-15) Table-21 (Primer composition-16) Table-22 (Primer composition-17) Table-23 (Primer composition-18) Table-24 (Comparative example-12) Table-25 (Comparative example-13) Next In order to examine the adhesion of the primer compositions-10 to 18, a tensile shear test was conducted using the following method.

A vinyl chloride resin having the composition shown in Table 26 was extruded at 170°C to produce a base material with a thickness of 2 mm.
Two test pieces were prepared by cutting into x 10 Q+*m squares.

Table 26 Next, as in Example 1, primer compositions 10 to 18 were applied to each side of the two test pieces, and then air-dried for 30 minutes at room temperature to form a single layer of primer. After applying the chloroprene rubber adhesive shown in Table 13 to the surface of the primer layer, the test pieces were air-dried for 30 minutes at room temperature, and the test pieces were bonded together and left at room temperature for 24 hours. and,
The tensile shear strength was measured in the same manner as in Example 1, and the results shown in Table 27 were obtained. Table 27 also shows the results of similar tensile shear tests using primer compositions 10 to 18 and primer compositions having the compositions shown in Tables 24 to 25 (Comparative Examples 12 to 13). Shown below.

Table 27 As a result, the tensile shear strengths of the test pieces using primer compositions 10 to 18 were all extremely high. In the primer compositions of Comparative Examples 12 and 13, the degree of chlorination of C70-PE was inappropriate, so the tensile shear strength decreased.

In addition, after applying the chloroprene rubber adhesive to the surface of each of the compositions of Comparative Examples 3 to 11 as an undercoat and bonding the test pieces, the tensile shear strength was measured using the method described above. The tensile shear strength of test pieces using these primers was extremely low (
1.0 kg/cnl or less).

From the above test results, the primer compositions-1 to 18
It has been found that all of these exhibit excellent adhesion as a primer when applying an adhesive to EPDM or vinyl chloride resin.

[Example 3] Next, the adhesion of the coating film when the primer compositions 1 to 9 were used as an undercoat when coating EPDM was measured by the following method.

The primer compositions 1 to 9 were applied to the EPDM test piece used in Example 1 by dipping, and after air-drying at room temperature for 30 minutes, the urethane composition having the composition shown in Table 28 was soaked in dry nitrogen. 80°C1 in gas
Apply the urethane O material obtained by reacting for 3 hours and leave it at room temperature: ?
: Cured for 24 hours.

Thereafter, the adhesion of the urethane coating applied to each test piece was measured by a cross-cut test, and as a result, all test pieces showed sufficient adhesion (100/'100).

On the other hand, each of the compositions of Comparative Examples 3 to 11 was applied to each of the test pieces by a dipping method and air-dried at room temperature for 30 minutes, and then the urethane paint was applied and cured at room temperature for 24 hours. The adhesion of these coatings was measured by a cross-over test, and the adhesion of all coatings was extremely weak (0/NOO).

[Example 4] Next, the adhesion of the coating film when the primer compositions -10 to 18 were used as an undercoat when coating a vinyl chloride resin was measured by the following method.

Each of the primer compositions-10 to 18 was applied to the test piece made of the vinyl chloride resin used in Example-2 by a dipping method, and after air-drying at room temperature for 30 minutes, the following results were obtained.
Apply a urethane paint with a composition of 28% to 24% at room temperature.
Allowed to cure for hours.

Thereafter, the adhesion of the urethane coating applied to each test piece was measured by a cross-cut test, and as a result, all test pieces showed sufficient adhesion (1,00/100).

On the other hand, each of the compositions of Comparative Examples 3 to 11 was applied to each of the test pieces by a dipping method and air-dried at room temperature for 30 minutes, and then the urethane paint was applied and cured at room temperature for 24 hours. The adhesion of these coatings was measured by a cross-cut test, and as in Example 3, the adhesion of all coatings was extremely weak (0/100).

From the above test results, the primer compositions-1 to 18
It has been found that all of these exhibit excellent adhesion as primers when coating paints on EPDM or vinyl chloride resin.

Next, an example of using the primer compositions-1 to 18 as an undercoat when applying paints or adhesives to various rubber products for automobiles will be described.

Usage Example 1: Door Weatherstrip EPDM is often used in door weatherstrips that seal the gap between the vehicle body and the door.

Therefore, primer compositions 1 to 18 were respectively applied to the surface of a weatherstrip base material made of EPDM, and then a urethane paint having the composition shown in Table 28 was applied thereon, and after air-drying at room temperature for 1 hour, A 5% by weight solution of dimethyl silicone oil (100,000 cSt) in toluene was applied.

Usage Example 2 EPDM is also widely used in the glass run used in the parts that slide against the window glass of Nigelas Land Assassins.

Therefore, each of primer compositions 1 to 18 was applied to the surface of a glass run base material made of E PDM, and then a urethane paint having the composition shown in Table 28 above was applied and air-dried at room temperature for 24 hours. .

Next, the abrasion resistance test of the coating film formed on the surface of the weather strip and glass run treated as described above was conducted in the following manner.

Testing machine = KI type abrasion testing machine Test conditions: Friction element glass (thickness 5mm) Load
3 kg Friction element cycle 60 times/min Friction element stroke 145 Dragon test method: A part of the above weather strip and glass run was attached to a testing machine, and the coating surface was rubbed according to the test conditions.

As a result, no exposure of the base material was observed in any case even after repeated friction 50,000 times.

Furthermore, an 18o6 bending test was conducted to check the followability of each of the above coating films, and all of them showed extremely good followability, and EP
The flexibility and flexibility, which are the characteristics of DM, were not impaired in any way.

Next, the above-mentioned abrasion resistance test was conducted using each of the compositions of Comparative Examples 3 to 11, but both the weather strip and the glass run exposed the base material by repeated friction 100 to 150 times.

Usage Example 3: Electrostatic flocking product Nigrasran includes a product whose sliding surface with the window glass is electrostatically flocked using fibers.

Primer compositions 1 to 18 were each applied to the glass run base material by a dipping method and left to stand at room temperature for 30 minutes, and then a urethane adhesive having the composition shown in Table 28 was applied to the surface, and then nylon-66 An electrostatic flocked product was obtained by electrostatically flocking a pile consisting of short fibers and curing the urethane adhesive with hot air.

Next, an abrasion resistance test of the coating film on the electrostatic flocked product treated as described above was conducted in the following manner.

Testing machine: Reciprocating type abrasion testing machine Test conditions: Friction element Glass (thickness 5 mm) Friction element cycle 60 times/min Friction element stroke 1451 Otori test method: Part of the above electrostatic flocking product was attached to the testing machine. , the coating surface was rubbed according to the test conditions.

As a result, no exposure of the base material was observed even after 20,000 repetitions of friction.

Furthermore, the primer compositions-1 to 18 can also be used for the following purposes.

Usage Example-4: Diaphragm made of acrylonitrile-butadiene copolymer rubber (NBR) coated with urethane paint having the composition shown in Table 28 after each of diaphragm primer compositions-1 to 18 was applied and left at room temperature for 30 minutes. In order to examine the gasoline resistance of the base material, it was immersed together with an untreated diaphragm in gasoline at 24° C. for 48 hours, and the mass change rate before and after immersion was measured using the following equation.

ΔW=((W! ”+)/W+) X 100
(%) (W+ is the mass before immersion and W2 is the mass after immersion.) As a result, the ΔW of the untreated diaphragm is 30
%, whereas the ΔW of the one subjected to the above treatment decreased to 20.1%, indicating that the primer composition of Example 4 is highly effective in improving the gasoline resistance of the diaphragm base material. There was found.

Usage Example 5 Nibble cylinder cup primer compositions 1 to 18 were respectively applied and left at room temperature for 30 minutes, and then a styrene-butadiene copolymer rubber (S In order to investigate the glycol resistance of the brake cylinder cup base material manufactured by B R), it was placed in commercially available low molecular weight ethylene glycol at 24°C and 20°C together with the untreated brake cylinder cup body.
After being immersed for 0 hours, the mass change rate ΔW before and after immersion was measured using the same method as for the diaphragm.

As a result, the Δ of the untreated brake cylinder cup body
W was 3.5%, whereas the ΔW of the treated product was reduced to 1.5%, indicating that the rubber composition was extremely effective in improving the glycol resistance of the brake cylinder cup body. It turned out that it shows.

Usage Example 5: Wiper Blade Primer compositions 1 to 18 were each applied to the surface of a wiper blade made of EPDM, and after being left at room temperature for 30 minutes, a urethane paint having the composition shown in Table 28 was applied. Superior followability compared to untreated ones,
In addition, a wiper blade with low frictional resistance during sliding was obtained.

From the above test results, it was found that Primer Compositions-1 to 18 are extremely useful as undercoating agents when coating paints and adhesives on polyolefin vulcanized rubber.

Further, the primer and mer compositions-1 to 18 can be used not only as primers but also as adhesives alone, and can also be used as paints by adding pigments, dyes, etc.

Effects of the Invention As detailed above, the primer composition of the present invention has extremely strong adhesion to various rubbers and synthetic resins such as polyopine vulcanized rubber, polyopine synthetic resin, and vinyl chloride resin. This invention is extremely excellent as an undercoat when applying adhesives or paints to the surfaces of base materials made of the various rubbers and synthetic resins mentioned above.

[Brief explanation of the drawing]

The figure is a cross-sectional view schematically showing a state in which a single layer of primer was formed on each end of two test pieces, and then the ends of both test pieces were joined via a chloroprene rubber adhesive. 1... One layer of primer, 2... Adhesive, 3... Test piece.

Claims (1)

[Claims] 1. (a) a chlorinated polyolefin or a chlorinated polyethylene-vinyl acetate copolymer; and (b) a saturated or partially saturated carbonized main chain with at least one hydroxyl group at the end of the molecule. A primer composition comprising a mixture of a hydrogen-based polymer and (c) an organic solvent. 2. The primer composition according to claim 1, wherein the chlorinated polyolefin has a degree of chlorination of 3 to 80%. 3. The primer composition according to claim 1, wherein the chlorinated polyethylene in the chlorinated polyethylene-vinyl acetate copolymer has a chlorination degree of 3 to 80%. 4. The hydrocarbon polymer has at least one hydroxyl group at the end and has an average molecular weight of 1000 to 500.
2. The primer composition according to claim 1, which is a polyhydroxypolyolefin of 0.