JPH0365794B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a multi-layered product having strong interlayer adhesion and having advantages such as weather resistance, chemical resistance, stain resistance, and abrasion resistance.

Thermoplastic fluorine-containing resin (hereinafter referred to as "fluorine-containing resin")
It is abbreviated as. ) generally has excellent solvent resistance, no water absorption, and has excellent weather resistance, heat resistance, abrasion resistance, and non-stick properties among plastics.

Polytetrafluoroethylene (PTFE) is a representative polymer of this fluororesin, and because of its high heat resistance and excellent solvent resistance, it is used as internal corrosion protection and packing for piping in chemical equipment, and because of its dielectric constant and It is used as an insulating material for electric wires and cables due to its low loss and high resistivity, and as an oil-free bearing and sliding material due to its excellent surface lubricity, but it has a high melting point and is difficult to melt by heating, making it difficult to form. However, it has the disadvantage that it has to be formed by sintering. Therefore, moldability has been improved by using fluorine-containing unsaturated monomers other than tetrafluoroethylene, copolymers with tetrafluoroethylene using other unsaturated monomers, or fluororesins that do not use tetrafluoroethylene. However, it has become possible to obtain thermoplastic materials that also have the properties of PTFE.

However, although these fluororesins have the above-mentioned properties, they are expensive, and therefore, for general purposes, it is thought that lamination with other inexpensive base materials will be useful.

However, since fluororesin is non-adhesive,
Difficult to adhere to other base materials.

[Conventional technology]

For this reason, various methods have been studied to improve the adhesiveness between fluororesins and other base materials. For example, methods of modifying the surface of fluororesin to improve adhesion include wet treatment of the surface of fluororesin molded products with an alkali metal solution, and dry treatment using corona discharge, plasma discharge, sputter etching, etc. There are known ways to treat it. In addition, there are methods such as a method of melting the surface with a special solvent that dissolves the fluororesin and adhering it to other base materials, and a method of physically adhering the glass mat and the fluororesin.

On the other hand, adhesive resins that bond fluororesin and other base materials have also been proposed. For example, certain ethylene-ethyl acrylate copolymers, ethylene-vinyl acetate copolymers, or modified products thereof
56-86748, JP 57-12645), epoxy group-containing polyolefin (JP 57-8155, JP 57-12645)
212055), a resin composition of a methyl methacrylate polymer and a copolymer obtained by grafting vinylidene fluoride onto a methyl methacrylate polymer (Japanese Patent Application Laid-open No. 12646/1983), and the like are known.

[Problem that the invention seeks to solve]

However, these prior art techniques are not satisfactory in terms of molding methods or adhesive properties, and there are limitations in the types of base materials to which they can be bonded.
In the lamination of a thermoplastic fluororesin and an ethylene-vinyl acetate copolymer disclosed in Publication No. 57-12645, a large amount of vinyl acetate is introduced in the form of copolymerization with ethylene to improve the adhesion. The mechanical strength of the copolymer was lowered, and the adhesive strength was not significantly improved, so it was not preferable.

The present inventor has conducted extensive research with the aim of easily obtaining a laminate in which fluororesin and metal are strongly laminated, which has advantages such as weather resistance, chemical resistance, stain resistance, and abrasion resistance. Ta.

[Means for solving problems]

As a result, the above object is achieved by laminating the A layer polymer or its composition on the metal surface via the following B layer or B layer/C layer/B layer polymer or its composition. The present invention was completed based on this finding.

That is, the present invention is a multi-layered product characterized in that layer A is laminated on the surface of a metal via layer B or layer B/layer C/layer B as described below.

A layer: an adhesive vinylidene fluoride polymer containing at least one functional group (a) selected from a carboxyl group, a hydroxyl group, and an epoxy group by blending or copolymerization from 1×10 ⁻³ to 0.3 mol/100 g; or Composition B layer: At least one type of functional group (b) selected from carboxyl group, hydroxyl group, and epoxy group, which is different from the above functional group (a), has a concentration of 1×10 ^{-3 to 1×10 −3} through reaction.
Modified α-olefin polymer or composition thereof introduced at 0.3 mol/100g Layer C: α-olefin polymer or composition thereof The present invention will be described in detail below.

The vinylidene fluoride-based polymer used in the present invention includes a homopolymer of vinylidene fluoride, vinylidene fluoride and less than half of its weight, preferably 30% by weight or less of other fluorine-containing monomers or non-fluorine-containing monomers. Copolymers with monomers, such as polyvinylidene fluoride, vinylidene fluoride-tetrafluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-chlorotrifluoroethylene copolymer, Vinylidene fluoride-vinyl fluoride copolymer, vinylidene fluoride-ethylene copolymer, vinylidene fluoride-
Examples include (meth)acrylic acid ester copolymers. Furthermore, it is also possible to use a blend of other polymers that are compatible with the vinylidene fluoride polymer, and a composition with a methyl methacrylate polymer is known as an example of such a polymer. In addition, it is also possible to blend various inorganic fillers, stabilizers, pigments, etc. that are normally blended.

The adhesive vinylidene fluoride polymer or its composition as the layer A constituting one layer of the multi-laminate of the present invention has carboxyl groups (including acid anhydride groups) and hydroxyl groups in the vinylidene fluoride polymer. and a composition containing at least one functional group (a) selected from the group consisting of epoxy groups.

The method for containing this functional group (a) is to blend a thermoplastic polymer that is compatible with the vinylidene fluoride polymer and has the functional group (a); There are methods such as random, block or graft copolymerization of polymerizable monomers.

In the case of the blending method, when blending a thermoplastic polymer that is compatible with the vinylidene fluoride polymer and has a functional group (a), the amount of the vinylidene fluoride polymer is 30% by weight or more, preferably 50
It should be at least 70% by weight, particularly preferably at least 70% by weight. If the amount is less than 30% by weight, the object of the present invention will not be achieved. Such thermoplastic polymers include:
Vinylidene fluoride polymers having a high concentration of functional group (a) can also be considered, but in general, (meth)acrylic acid ester polymers and vinylidene fluoride polymers having functional group (a) are considered. It is preferable to use a polymer monomer having compatibility with the above, such as a copolymer of a (meth)acrylic acid ester or a fluorine-containing monomer and a monomer having a functional group (a).

Here, examples of monomers having the functional group (a) include the following.

That is, examples of the functional group (a) being a carboxyl group include acrylic acid, methacrylic acid, maleic acid, itaconic acid, hymic acid, and their anhydrides, among which acrylic acid and maleic anhydride are Preferable in terms of adhesiveness.

Examples of functional group (a) being an epoxy group include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate, etc. Among them, glycidyl acrylate and glycidyl methacrylate are the most reactive in terms of reactivity. preferable.

When selecting a hydroxyl group as the functional group (a), it is necessary to copolymerize a vinyl ester such as vinyl acetate or vinyl propionate and then hydrolyze it, or to copolymerize a vinyl ester such as vinyl acetate or vinyl propionate and then hydrolyze it, or to copolymerize a hydroxyl group such as an ester of acrylic acid or methacrylic acid with a dihydric alcohol. Preferably, the saturated alcohol is introduced by copolymerization.

As the adhesive vinylidene fluoride polymer or its composition, a composition of a vinylidene fluoride polymer and a (meth)acrylic acid ester polymer having the above-mentioned functional group (a), or a composition of vinylidene fluoride and a (meth)acrylic acid ester polymer having the above functional group (a), A random or graft copolymer with a monomer having the above functional group (a) has convenience, adhesive properties,
It is preferable in terms of moldability and the like.

The content of the functional group (a) in the adhesive vinylidene fluoride polymer or its composition, which is layer A, is 1×10 ^-3
~0.3 mol/100g, preferably ^5x10-3 ~0.2 mol/100g, particularly preferably ^{1x10-2 ~} 0.1 mol/100g
It is 100g. This range is a numerical value determined from evaluation of adhesiveness, moldability, and physical properties.

Next, the modified α-olefin polymer or its composition of the B layer constituting one layer of the multi-laminate of the present invention has the functional group (a) described in the above A layer in the α-olefin polymer. [This corresponds to the functional group (b) of the present invention. ] is a modified α-olefin polymer introduced by reaction, or a composition obtained by diluting this with a compatible thermoplastic polymer such as an α-olefin polymer.

The reaction method for introducing the functional group (a) into the α-olefin polymer is a method of random, block or graft copolymerization of a polymerizable monomer having the above-mentioned functional group (a); A method of reacting a group with a compound having a functional group (a) or a compound that generates a functional group (a) by reaction; a method of modification such as oxidation or hydrolysis, and the like. Among these, the method by copolymerization and the method by hydrolysis or thermal decomposition are preferable because they can easily introduce the functional group (a) and the amount of introduction can be easily controlled.In particular, the adhesiveness is improved by introducing a small amount of the functional group. Graft or random copolymers are preferred because they do not significantly impair the physical properties of the resin used for modification.

Here, the α-olefin polymers include homopolymers and copolymers of α-olefins such as ethylene, propylene, butene, hexene, octene, and decene, such as polyethylene, polypropylene, ethylene-propylene copolymers, ethylene-
Butene-1 copolymer, ethylene-4-methylpentene-1 copolymer, propylene-butene-1 copolymer, polybutene-1; the above α-olefin and less than half its weight, preferably 30% by weight or less Copolymers with diolefins, unsaturated carboxylic acid esters, etc., such as ethylene-butadiene copolymers, propylene-butadiene copolymers, ethylene-vinyl acetate copolymers, and ethylene-ethyl acrylate copolymers, are preferred. is preferably a crystalline resin. These may be used in combination. In particular, low-crystalline or amorphous elastomers, such as ethylene-propylene rubber, ethylene-butene-1 rubber,
α-olefin copolymer rubber such as propylene-butene-1 rubber, ethylene-propylene-diene rubber, isoprene rubber, isobutylene rubber, etc.
It is preferable to mix 10 to 50% by weight, preferably 10 to 50% by weight, since the adhesion with the layer A is improved. As the elastomer, α-olefin copolymer rubber is particularly preferred from the viewpoint of improving compatibility with the modified α-olefin polymer and adhesion.

A thermoplastic polymer that is incompatible with the modified α-olefin polymer or its composition can be blended in an amount of 30% by weight or less. Examples of the incompatible thermoplastic polymer include polyamide, polyester, etc., which can be blended into layer B in order to recycle burrs and smudges generated during molding of the multilayer molded product of the present invention. In that case, the constituent components of layer A may be blended into layer B, which is practically preferable.

The content of the functional group (b) in the modified α-olefin polymer or its composition, which is layer B, is 1 × 10 ^-3 ~
0.3 mol/100g, preferably 5×10 ^-3 to 0.2 mol/
100g, particularly preferably 1×10 ^-2 to 0.1 mol/100
It is g. This range is a numerical value determined from evaluation of adhesiveness, moldability, and physical properties.

Furthermore, the α-olefin polymer or its composition in the C layer constituting one layer of the multi-laminate of the present invention may be the α-olefin polymer or a composition thereof described in connection with the B layer, or a composition thereof. This is a composition containing 30% by weight or less of other thermoplastic polymers. This thermoplastic polymer may also contain constituent components of layer A, which are obtained by recycling burrs and smudges from the multilayer molded product of the present invention.

Note that the B layer and the C layer can also be crosslinked using peroxide, vinyl silane, etc., if necessary.

Further, metals constituting one layer of the multilayer structure of the present invention include iron, aluminum, zinc, tin,
Examples include lead and copper, and foil, plate, and tubular materials are used. The metal surface can be mechanically roughened by sandblasting, shotblasting, etc. before lamination, degreasing by pickling, alkaline washing, etc., chemical conversion treatment with phosphates, chromates, etc., or epoxy resin. Pretreatment can be carried out by applying a primer such as urethane resin, unsaturated polyester resin, or organic silicon compound.

[Effect]

The multi-laminate of the present invention is manufactured by preheating the metal to a desired temperature and then laminating each layer in a molten state, for example (1) layer A/layer B or layer A/layer. Method for extrusion laminating a coextruded sheet of layer B/layer C/layer B (2) A laminated sheet of layer A/layer B or layer A/layer B/layer C/layer B is placed on a metal surface, and then heated roll or Method of pressure bonding using a heated press (3) Methods such as powder coating the B layer and then powder coating the A layer, press, heat sealing, extrusion lamination, pressure bonding with a heated roll, coextrusion, etc. can.

At this time, the A layer and the metal are B layer or B layer/C
It is important that the layers are laminated through layer/B layer.

Moreover, the functional group (b) contained in layer B is
It is difficult to obtain strong interlayer adhesion unless a group different in type from the functional group (a) contained in the layer is selected. A preferable combination of functional group (a) and functional group (b) is one that has the possibility of chemically reacting with each other,
Examples include (1) a combination of a carboxyl group and an epoxy group or a hydroxyl group, and (2) a combination of an epoxy group and a hydroxyl group. In this sense, particularly preferred combinations of layer A and layer B are (1) a carboxyl group-containing α-olefin polymer and an epoxy group-containing vinylidene fluoride polymer, (2) an epoxy group-containing α-olefin polymer. and a carboxyl group-containing vinylidene fluoride polymer.

Note that the multilayer body of the present invention has these A/B/
This also applies to a laminate having a constituent layer in which other layers are laminated on a metal or A/B/C/B/metal layer. At this time, the other layer coated on the opposite side of the metal or on the outside of layer A may be made of a base material, for example, a halogen-based resin such as vinyl chloride polymer, vinylidene chloride polymer, vinylidene fluoride polymer; Styrenic resins such as acrylonitrile-butadiene-styrene resin and polystyrene; Acrylic resins such as polymethyl methacrylate; α-olefin resins such as polyethylene and polypropylene;
Acrylonitrile-butadiene rubber, styrene-
Various rubbers such as butadiene rubber; thermosetting resins such as unsaturated polyester, epoxy resin, urethane resin; thermoplastic polyester, polycarbonate,
Possible materials include engineering resins such as nylon.

The multi-layered product of the present invention can be used as weather-resistant/corrosion-resistant piping, decorative board, tank inner lining, etc.
Olefin polymer/Metal, adhesive vinylidene fluoride polymer/Modified α-olefin polymer/α
- Olefin polymer/modified α-olefin polymer/metal, polyvinylidene fluoride/adhesive vinylidene fluoride polymer/modified α-olefin polymer/metal, etc. are used in a layer configuration.

Furthermore, for applications requiring weather resistance, it is preferable to add pigments, ultraviolet absorbers, etc. to the A, B, and C layers and the vinylidene fluoride polymer layer as necessary.

In addition, in the multi-layered product of the present invention, the above A and B
The thickness of each layer of and C is approximately 10~
1000μ, 10-1000μ and 10-5000μ are suitable.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples. In addition, the evaluation of adhesion in the examples was based on the following method.

Adhesion: Cut only the resin part of the multi-laminate into a strip test piece with a specified width, peel off part of the resin part, then insert it into the chuck of an Instron type testing machine and peel at 90 degrees at a speed of 50 mm/min. Measured at

Example 1 95 and 80% by weight of polyvinylidene fluoride (Pennwalt, "KYNA-720") and methyl methacrylate-glycidyl methacrylate copolymer (glycidyl methacrylate content: 0.35 mol/100 g)
5 (epoxy group content 0.018 mol/100g) and 20% by weight (epoxy group content 0.070 mol/100g)
were kneaded in an extruder at 210°C to obtain an adhesive vinylidene fluoride polymer composition.

This adhesive vinylidene fluoride polymer composition and maleic anhydride modified ethylene polymer (MFR1.5
g/10 min, density 0.93 g/cm ³ , carboxyl group content
0.011 mol/100g) were laminated at 210°C by compression molding. Next, this laminated sheet is compressed into a sandblasted steel plate (hot rolled steel plate, 150℃) at 210℃.
x 70 x 4 mm, sand roughness No. 20) and an adhesive vinylidene fluoride polymer composition layer (1 mm)/
Modified ethylene polymer layer (1mm)/steel plate (4mm)
A laminate, that is, a resin-coated steel plate was obtained.

The adhesive strength of the obtained coated steel sheet was 1.5 Kg/cm between the steel sheet and the modified ethylene polymer when the methyl methacrylate-glycidyl methacrylate copolymer content was 5% by weight, and the adhesive strength with the modified ethylene polymer was 1.5 kg/cm. When the distance between the vinylidene fluoride polymer composition is 1.1 Kg/cm and the methyl methacrylate-glycidyl methacrylate copolymer content is 20% by weight, the distance between the steel plate and the modified ethylene polymer is 1.5 Kg/cm, The weight difference between the modified ethylene polymer and the adhesive vinylidene fluoride polymer composition was 1.2 kg/cm.

Example 2 The adhesive vinylidene fluoride polymer composition containing 20% by weight of the methyl methacrylate-glycidyl methacrylate copolymer used in Example 1 and the maleic anhydride-modified propylene polymer (MFR 1.0 g/ Ten
Min., density 0.89g/cm ³ , carboxyl group content 0.005
A resin-coated steel plate was obtained in the same manner as in Example 1 using mol/100g).

The adhesive strength of the obtained coated steel sheet was 2.5 kg/cm between the steel sheet and the modified propylene polymer, and 2.2 kg/cm between the modified propylene polymer and the adhesive vinylidene fluoride polymer composition. Ta.

Comparative Example In Examples 1 and 2, when an unmodified olefinic polymer was used, there was also a gap between the steel plate and the olefinic polymer and between the olefinic polymer and the adhesive vinylidene fluoride polymer composition. When modified polyvinylidene fluoride was used, there was no adhesion between the modified olefin polymer and polyvinylidene fluoride.

Example 3 The adhesive vinylidene fluoride polymer composition containing 20% by weight of the methyl methacrylate-glycidyl methacrylate copolymer used in Example 1, maleic anhydride-modified ethylene polymer, and high-density polyethylene ( Adhesive vinylidene fluoride polymer composition layer (0.5 ^mm )/modified ethylene polymer layer (0.1 mm) / high-density polyethylene layer (1.5 mm) / modified ethylene polymer layer (0.1
A resin-coated steel plate with a diameter of 4 mm)/steel plate was obtained.

The adhesive strength of the obtained coated steel plate was 1.7 kg/cm between the steel plate and the modified ethylene polymer layer, non-peelable between the modified ethylene polymer layer and high-density polyethylene layer, and adhesive strength between the modified ethylene polymer layer and the modified ethylene polymer layer. The interlayer density of the vinylidene polymer composition was 1.2 kg/cm.

Example 4 70 parts by weight of vinylidene fluoride polymer (PVDF: “Kynar 2800” manufactured by Pennwalt) and Example 1
and 30 parts by weight of the methyl methacrylate-glycidyl methacrylate copolymer (MMA-GMA copolymer) used in the above were kneaded in an extruder at 210°C to obtain an adhesive vinylidene fluoride polymer composition.

This composition was fed to an extruder with a diameter of 50 mm at 200°C,
The modified ethylene polymer used in Example 1 was heated to 230°C.
It was then fed to an extruder with a diameter of 50 mm. These two resins were bonded together in a coextrusion die set at 200℃,
A two-layer film with a configuration of 50μ each was obtained.

The modified ethylene polymer layer of this two-layer film was placed on the steel plate side, and was bonded to various surface-treated steel plates by compression molding at 180°C. The adhesive strength between the steel plate and the modified ethylene polymer is as follows when the steel plate is chromate treated.
1.0Kg/cm, 1.0Kg/cm for phosphate treatment, and 1.2Kg/cm for epoxy treatment.

Example 5 70 parts by weight of PVDC used in Example 4 and 30 parts by weight of methacrylic methyl-acrylic acid copolymer (MMA-AA copolymer: acrylic acid content 0.69 mol/100 g) were kneaded in an extruder at 210°C. An adhesive vinylidene fluoride polymer composition was obtained.

This composition and glycidyl methacrylate modified propylene polymer (modified PP: MFR 2g/10 minutes,
Density 0.90g/cm ³ , glycidyl methacrylate content
A composition consisting of 70 parts by weight of ethylene-propylene rubber (EPR: ethylene content 74% by weight, Mooney viscosity ML 100°C 1+475) was laminated at 210°C by compression molding.

Next, this laminated sheet was laminated to a steel plate in the same manner as in Example 1, and the adhesive strength was measured. As a result, the adhesive strength between the steel plate and the modified propylene polymer composition was 1.5 kg/1.
cm, the difference between the modified propylene polymer composition and the adhesive vinylidene fluoride polymer composition was 1.8 Kg/cm.

Example 6 70 parts by weight of PVDF used in Example 4 and methyl methacrylate-2-hydroxyethyl methacrylate copolymer (MMA-HEMA copolymer: 2-hydroxyethyl methacrylate content 0.008 mol/100 g)
30 parts by weight were kneaded in an extruder at 210°C to obtain an adhesive vinylidene fluoride polymer composition.

This composition and the modified ethylene polymer used in Example 1 were laminated to a steel plate in the same manner as in Example 1,
When the adhesive strength was measured, it was 1.5 kg/cm between the steel plate and the modified ethylene polymer, and 1.5 kg/cm between the modified ethylene polymer and the adhesive vinylidene fluoride polymer composition.
It was 1.0Kg/cm.

〔Effect of the invention〕

The multiple laminate of the present invention has each layer firmly bonded to each other, has excellent weather resistance, chemical resistance, stain resistance, abrasion resistance, etc. on the inner or outer surface, and has a good appearance. This has the remarkable effect of being easily manufactured by a simple molding method.

Claims (1)

[Scope of Claims] 1. A multi-layered product characterized in that a layer A is laminated on the surface of a metal via the following B layer or B layer/C layer/B layer. A layer: adhesive vinylidene fluoride polymer containing at least one functional group (a) selected from carboxyl group, hydroxyl group, and epoxy group by blending or copolymerization in an amount of 1 x 10 ^-3 to 0.3 mol/100 g. Or the composition B layer: at least one selected from carboxyl group, hydroxyl group and epoxy group, and the above functional group (a)
The functional group (b) different from 1 × 10 ^-3 ~
Modified α-olefin polymer or composition thereof introduced at 0.3 mol/100g Layer C: α-olefin polymer or composition thereof