JP3027035B2 - Metal-resin composite material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite material of a metal material and a molded article of a vinyl chloride resin.

[0002]

2. Description of the Related Art Conventionally, metal water storage / storage tanks, hot water supply / drainage pipes, and the like have corrosion on the metal surface due to direct contact with hot water, an acid, or an alkaline aqueous solution. Composite materials obtained by laminating molded bodies such as vinyl chloride resin plates and pipes with an adhesive are widely used.

[0003] However, in a state where the above-mentioned composite material is repeatedly heated and cooled in a state where the composite material is in contact with water, or a condition where a temperature difference occurs between the laminated metal material and the resin molded product side. When placed on the surface of the resin molded body, the moisture in contact with the resin molded body reaches the interface between the metal and the adhesive through the resin layer and the adhesive layer.

[0004] In this manner, when the water reaches the interface, the adhesive layer and the metal are separated, and the water is continuously supplied, so that the resin molded body is blistered (blistered). ) Will occur. [Journal of the Adhesion Society of Japan, Vol. 26, no. 4 (1990)] In particular, once such blisters are generated in a composite material in which a vinyl chloride pipe is lined on the inner surface of a metal pipe,
It grows rapidly and grows, eventually plugging the tube, which can lead to major accidents.

[0005] The occurrence of such blisters is related not only to the water resistance of the adhesive used between the metal material and the resin molded product but also to the adhesive strength, and is unlikely to occur with an adhesive having excellent adhesive strength. It is known.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks.
Even if it is subjected to repeated heating and cooling, or is used under conditions where a temperature difference occurs between the metal side and the resin molded body, blister generation and growth can be suppressed, and long-term use is possible. It is intended to provide a durable resin-metal composite material.

[0007]

According to the metal-resin composite material of the present invention, the metal material and the vinyl chloride resin molded product contain at least one hydrolyzable silicon and / or silanol group in the molecule, When the main chain is essentially -RO- (R is 2
Characterized by being laminated via an adhesive consisting of a mixture of a modified silicone resin composed of a repeating unit represented by a divalent alkylene group) and an epoxy resin, thereby achieving the above object. Is done.

Hereinafter, the present invention will be described in detail. Examples of the metal material used in the present invention include mild steel, semi-hard steel, hard steel, stainless steel, aluminum and other plates, pipes, corrugated plates, and the like.

As the vinyl chloride resin, a vinyl chloride homopolymer, a mixture of a vinyl chloride homopolymer and a chlorinated vinyl chloride homopolymer, or a vinyl chloride homopolymer and a vinyl chloride copolymer (vinyl acetate-chloride) Mixtures of vinyl, vinyl chloride-vinylidene chloride, vinyl acetate-vinyl chloride-maleic anhydride, etc.) are preferably used.

The weight average degree of polymerization of the vinyl chloride homopolymer is preferably in the range of 400 to 1600, and the weight average degree of polymerization of the chlorinated vinyl chloride homopolymer is 400 to 100.
A range of 0 is preferred.

The above-mentioned vinyl chloride resin may be added with, for example, a modifier (polymethyl methacrylate, polybutadiene, etc.)
Reinforcing materials (glass fiber, carbon black, white carbon, etc.), fillers (calcium carbonate, talc, etc.),
Stabilizers (phenol-based, tin-based, etc.), pigments, dyes and the like may be added.

Further, as a vinyl chloride resin molded article,
For example, plates and pipes molded from vinyl chloride resin,
Rods, corrugated plates, and the like are included. The thicker the vinyl chloride-based resin molded body, the longer it takes for moisture to reach the interface between the metal material and the adhesive layer, so that the generation of blisters can be delayed.

Usually, the thickness of the vinyl chloride resin molded product is
0.3 to 20 mm is used. The adhesive used in the present invention is mainly composed of a modified silicone resin and an epoxy resin.

The modified silicone resin contains at least one hydrolyzable silicon and / or silanol group in the molecule, and the main chain is essentially -RO- (R represents a divalent alkylene group). And a molecular weight of 500 to 15,000.
Is suitable.

As such a modified silicone resin, for example, Cyril 5B25 (Kanebuchi Chemical Co., Ltd.) is commercially available. The modified silicone resin is cured by reacting with moisture, but a reaction accelerator may be added to promote the reaction between the hydrolyzable silicon and silanol groups and moisture.

As the reaction accelerator, for example, organic tin salts such as dibutyltin oxide, dibutyltin dilaurate, dibutyltin phthalate and dibutyltin dichloride are preferably used.

As the epoxy resin, bisphenol type epoxy resin is preferred. As the curing agent, for example, tris (dimethylaminomethyl) phenol and its organic acid salt, dimethylbenzylamine, 1,8-diazabicyclo Tertiary amines such as (5,4,0) undecane and triethylenediamine are preferably used.

Here, the mixing ratio between the main component and the curing agent is appropriately determined depending on the use conditions. In addition, the modified silicone resin and the epoxy resin, if necessary, a phenol resin, sulfur, a silane coupling agent, an adhesion imparting agent such as a titanium coupling agent, calcium carbonate, magnesium carbonate, talc, titanium oxide and the like. Fillers may be added.

When using the above adhesive, if necessary, a modified silicone resin to which a reaction accelerator has been added and an epoxy resin to which a curing agent has been added are mixed well, and then the adhesive obtained by mixing this is coated. Apply to the landing surface.

For applying the adhesive to the surface to be adhered, any method may be employed. For example, brush coating, dipping, spraying, roll coater and the like can be used. Usually, the coating thickness of the adhesive is preferably in the range of 10 to 1000 μm.

Further, the surface of the metal material is usually subjected to a pretreatment such as sandblasting, alkali washing, and pickling prior to application of the adhesive in order to improve the adhesiveness. Similarly, the surface of the vinyl chloride resin molded product is subjected to sandpaper polishing and pretreatment with an organic solvent such as acetone.

[0022]

In the metal-resin composite material of the present invention, by using the adhesive composed of the modified silicone resin and the epoxy resin as described above, water having penetrated from the resin side can be combined with the adhesive exhibiting excellent adhesive strength. In the denatured silicone resin, it is trapped as a minute unit and the arrival at the interface between the adhesive layer and the metal is delayed, so the moisture permeating from the resin side causes the interface between the adhesive layer and the metal to peel off. Difficult
Blister formation and growth will be prevented.

[0023]

Embodiments of the present invention will be described below. (Example 1) 1) Preparation of adhesive Modified silicone resin (“Silyl 5B25” manufactured by Kanegafuchi Chemical)
To 100 parts by weight, 1 part by weight of dibutyltin dilaurate (“SATNN-SB65” manufactured by Sankyokisei) and 60 parts by weight of calcium carbonate (“Whiten SB” manufactured by Shiroishi Calcium) were added as a reaction accelerator. A) was prepared.

Separately, 2,4,6-tris (dimethylaminomethyl) phenol ("SATNN-SB65" manufactured by Wako Pure Chemical Industries, Ltd.) is used as a curing agent in 20 parts by weight of an epoxy resin ("Epicoat 828" manufactured by Yuka Shell Epoxy). The composition (B) was prepared by adding 2 parts by weight.

The composition (A) and the composition (B) were mixed to prepare an adhesive. 2) Preparation of composite material for test As a metal material, a steel plate cut into 100 mm square (JIS
SS34P, 3 mm thick).

Prior to the application of the adhesive, the adhered surface of the steel sheet was subjected to sandblasting, and then immersed in a 5% NaOH aqueous solution for 2 minutes and washed with water. Next, the resultant was added in 5% nitric acid and immersed for 2 minutes, washed with water and dried with a hot-air drier to perform a pretreatment.

Separately, as a vinyl chloride resin molded product,
Hard vinyl chloride plate (Mitsubishi Resin,
(0.5 mm thick), the surface to be adhered was polished with sandpaper, and the surface was washed with a mixed solvent of an equal amount of MEK and acetone to perform a pretreatment.

The adhesive prepared in the above 1) is applied to the pretreated steel sheet and the hard vinyl chloride sheet with a coating thickness of 150 to 200 μm.
m and apply it with a doctor blade so that
After forming the laminate, it was left in a thermostat at 30 ° C. for 30 minutes. Next, a uniform load of 5 kg / cm ² was applied to the laminate, left for 10 hours in a constant temperature bath at 40 ° C., and after the adhesive was cured, the load was removed.
After curing for 8 hours, a test composite material was prepared. 3) Blister accelerated test The test composite material prepared in 2) was loaded with 7
The steel sheet was immersed in warm water at 5 ° C so that the steel sheet side was in contact with water at 25 ° C, and a blister acceleration test was performed.
The state of blister generation on day 0 was observed.

With respect to the blister generation status, observations were made for each evaluation item of the number of blisters generated, the diameter, and the area (occupancy) of the blisters in the total bonded area, and the results are shown in Table 2. (Example 2) A mixture of 100 parts by weight of the modified silicone resin of Example 1 mixed with 1 part by weight of dibutyltin dilaurate and 75 parts by weight of calcium carbonate (A), and an epoxy resin 50
The test was conducted in the same manner as in Example 1 except that an adhesive was prepared by mixing (B) to which 5 parts by weight of 2,4,6-tris (dimethylaminomethyl) phenol was added. A composite material was prepared and subjected to a blister acceleration test. The results are shown in Table 2. Example 3 A mixture of 100 parts by weight of the modified silicone resin of Example 1, 1 part by weight of dibutyltin dilaurate and 90 parts by weight of calcium carbonate (A), and an epoxy resin 80
A test piece was prepared in the same manner as in Example 1 except that an adhesive was prepared by mixing (B) to which 8 parts by weight of 2,4,6-tris (dimethylaminomethyl) phenol was added. A composite material was prepared and subjected to a blister acceleration test. The results are shown in Table 2. (Comparative Examples 1-2) Using an adhesive having a composition shown in Table 1,
A test composite material was prepared and subjected to a blister acceleration test in the same manner as in Example 1. The results are shown in Table 2.

[0030]

[Table 1]

[0031]

[Table 2]

(Examples 4 to 6) Using the adhesive composition shown in Table 3, a test composite material was produced in the same manner as in Example 1, and the vinyl chloride plate side was heated to 75 ° C. in hot water. The same procedure as in Example 1 was carried out except that the blister acceleration test was performed by immersing the side in contact with warm water at 55 ° C.
A blister acceleration test was performed and the results are shown in Table 4. (Comparative Examples 3 to 5) Example 1 was performed using the adhesive composition shown in Table 3.
A composite material for test was prepared in the same manner as described above, and a blister acceleration test was performed in the same manner as in Example 4. The results are shown in Table 4.

[0033]

[Table 3]

[0034]

[Table 4]

(Examples 7 to 9) Instead of a steel plate, an aluminum plate (JIS H1401, AIP0-0, thickness 3 mm)
Using the adhesive composition shown in Table 5, a test composite material was prepared, and the vinyl chloride plate was immersed in 75 ° C. hot water and the aluminum plate was immersed in 55 ° C. hot water and blistered. Example 1 except that an accelerated test was performed
A blister acceleration test was performed in the same manner as in Example 1 and the results are shown in Table 6. (Comparative Examples 6 to 8) Using the adhesive composition shown in Table 5, Example 1
A composite material for testing was prepared as in Example 1 and a blister acceleration test was performed in the same manner as in Example 7. The results are shown in Table 6.

[0036]

[Table 5]

[0037]

[Table 6]

[0038]

The metal-resin composite material of the present invention, when laminated using an adhesive composed of a modified silicone resin and an epoxy resin, exhibits excellent adhesive strength and ensures that the resin side is in contact with water or hot water. Even when used under conditions such as those that cause a temperature difference between the resin side and the metal side, blistering and growth can be significantly suppressed.

Claims (1)

(57) [Claims] 1. The method according to claim 1, wherein the metal material and the vinyl chloride-based resin molded product have at least one hydrolyzable silicon and / or
Or containing a silanol group, wherein the main chain is essentially -RO-
(R represents a divalent alkylene group) A metal-resin which is laminated via an adhesive made of a mixture of a modified silicone resin composed of a repeating unit represented by the following formula and an epoxy resin. Composite materials.