JPH0354051B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a laminate including a metal layer and a polymer layer and a method for producing the same. [Prior art] Polyolefin resin is non-polar and has excellent chemical and electrical properties, and is used in various fields. However, on the other hand, it has extremely poor adhesive properties, so it is difficult to It could not be used for the intended purpose at all. Therefore, various improvement methods have been proposed in order to impart adhesive properties to polyolefin resins, and one of them is to add polyolefin resins to γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane,
A method has been proposed for improving the adhesiveness of polyolefin resins by modifying them with a type of modifier selected from glycidyl methacrylate and an organic peroxide. [Problems to be Solved by the Invention] However, the improvement in adhesion of the modified polyolefin obtained by this method is still not satisfactory. In particular, when this modified polyolefin is used as an adhesive for bonding metal plates such as chrome-plated steel plates and stainless steel plates, it is necessary to degrease the adhesive surface of the metal plates in advance. Even when metal plates are bonded together, the adhesive strength of the resulting laminate is still not satisfactory. A laminate of a metal layer and a polymer layer using such modified polyolefin as an adhesive layer does not have a satisfactory adhesive strength. For this reason, the range of use of conventional laminates has been largely limited. [Means for Solving the Problems] The present inventors have conducted extensive research with the aim of providing a laminate in which a metal layer and a polymer layer are firmly adhered via an adhesive layer mainly composed of polyolefin resin. As a result, the present invention was completed. That is, the present invention provides a modified polyolefin obtained by graft-modifying a crystalline polyolefin resin with an organic silane compound having an ethylenically unsaturated bond under heating to form a metal layer and a polymer layer.
A uniform adhesive polyolefin composition with a thickness of 1μ or more consisting of 10 to 80% by weight of an unmodified crystalline polyolefin resin and 5 to 50% by weight of powdered calcium carbonate (100% by weight in total). This invention relates to a laminate formed by laminating layers with an adhesive layer interposed therebetween. Furthermore, the present invention provides a modified polyolefin 10 to 80% polyolefin resin obtained by graft-modifying a polyolefin resin with an organic silane compound having an ethylenically unsaturated bond under heating between the metal layer and the polymer layer.
Weight% and unmodified crystalline polyolefin resin 10~
80% by weight and powdered calcium carbonate 5-50% by weight
(100% by weight in total), and heat-pressing is carried out so that the adhesive layer formed thereby has a thickness of 1μ. be. In the present invention, the metal forming the metal layer is not particularly limited, and examples thereof include iron, aluminum, chromium, nickel, gold, silver, copper, zinc, tin, steel, stainless steel, galvanized iron, tinplate, etc. Iron, steel, stainless steel and aluminum are preferred. The metal may be plate-shaped, tubular, or rod-shaped, and is usually plate-shaped, and may or may not be degreased. In the case of a metal tube, either the inner or outer surface of the tube may be used. In the present invention, the polymer forming the polymer layer is not particularly limited, and polyolefins such as polypropylene (crystalline homopolymer,
crystalline random or block copolymers of propylene and ethylene or other α-olefins, such as butene-1, hexene, octene, etc.),
Polyethylene (ethylene homopolymer, ethylene-
vinyl acetate copolymers, copolymers of ethylene and α-olefins, such as butene-1, hexene, octene, etc.), natural rubber, elastomers (ethylene-propylene, ethylene-propylene-nonconjugated dienes, ethylene-acrylic esters) , ionomers, copolymers such as styrene-butadiene, polybutadiene), and those modified by addition with derivatives such as unsaturated acids, acid esters, metal salts, imides, amides, etc., or partially crosslinked products are also used. can do. Known inorganic fillers such as calcium carbonate, talc, carbon black, metal powder, fibrous materials and woven fabrics thereof, etc. can be added to these polymers as necessary. The amount added is appropriately determined depending on the use of the laminate. The polymer layer may also be a foam having closed cells or open cells. The polymer layer preferably has a thickness of 0.01 to 20 mm, particularly 0.1 to 5 mm. The polymer layer (and adhesive) may also contain conductive fillers, such as carbon fibers, metal fibers, etc.
Metal plating of flakes or powders or fillers can be added to enable spot welding of metal laminates (basic structure: metal layer-adhesive layer-polymer layer-adhesive layer-metal layer). In the present invention, 10 to 80% by weight of a modified polyolefin obtained by graft-modifying a crystalline polyolefin resin with an organosilane compound having an ethylenically unsaturated bond under heating and 10 to 80% by weight of an unmodified polyolefin resin. It is necessary to use a uniform adhesive layer with a thickness of 1μ or more, preferably 10 to 80μ, consisting of an adhesive polyolefin composition of powdered calcium carbonate and 5 to 50% by weight (total 100% by weight). This allows the metal layer and the polymer layer to be firmly bonded together via the adhesive layer. Also, various combinations of polymer layers and adhesive layers are possible. The above-mentioned modified polyolefin can be obtained by graft-modifying the polyolefin resin by heating in the presence of a crystalline polyolefin resin, an organic silane compound having an ethylenically unsaturated bond, and preferably an organic peroxide. The polyolefin resin may be a crystalline homopolymer of propylene or other α-olefins (e.g., ethylene, butene, pentene, hexene,
Crystalline propylene polymers such as binary or random copolymers with heptene, etc.), ethylene homopolymers with a density of 0.93 g/ ^cm3 or more, and copolymers with ethylene whose content is Examples include ethylene polymers such as binary or more block or random copolymers with up to about 15% by weight of other α-olefins (propylene, butene, pentene, hexene, heptene, etc.). Among these, random or block copolymers of ethylene and propylene with an ethylene content of 2 to 15% by weight, or a density of 0.93 g/
Preferably, up to 50% by weight, particularly up to 25% by weight, of an ethylene polymer having a mass of 3 cm ³ or more is mixed. Also,
The melt flow rate (MFR) of polyolefin resin is 0.01 to 20 g/10 minutes, especially 0.1 to 10 g/10
Preferably. A stabilizer or the like may be added to the polyolefin resin. In addition, examples of the above-mentioned organic silane compounds having ethylenically unsaturated bonds (hereinafter also simply referred to as modifiers) include vinyltriethoxysilane, methacryloyloxytrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, and methacryloyloxypropyltrimethoxysilane. Examples include acryloyloxycyclohexyltrimethoxysilane, γ-methacryloyloxypropyltriacetyloxysilane, methacryloyloxytriethoxysilane, γ-methacryloyloxypropyltriethoxysilane, and the like. In the present invention, other modifiers may be used in combination with the organosilane compound having an ethylenically unsaturated bond. Such modifiers are not particularly limited and include, for example, allyl glycidyl ether, 2-methyl-allyl glycidyl ether, sodium acrylate, sodium methacrylate, calcium acrylate, calcium methacrylate, magnesium acrylate, and methacrylic acid. Metal salt compounds of (meth)acrylic acid such as magnesium, zinc acrylate, zinc methacrylate, aluminum acrylate, aluminum methacrylate, iron acrylate (), iron methacrylate (), triallylcyanurate, tri- (2-methylallyl) cyanurate,
1,3,5-triacryloylhexahydro-s
-triazine, 1,3,5-trimethacryloylhexahydro-s-triazine, 4-acryloyloxyphenol, 4-(acryloyloxymethyl)phenol, 4-acryloyloxybenzyl alcohol, 4-methacryloyloxyphenol, 4- Examples include methacryloyloxybenzyl alcohol and 4-(methacryloyloxymethyl)benzyl alcohol. Furthermore, the organic peroxide mentioned above is preferably one having a 1-minute half-life temperature of about 160 to 260°C, such as tert-butylperoxyisopropyl carbonate, di-tert-butylperoxyisopropyl carbonate, etc. Butyl diperoxyphthalate, tert-butyl peroxyacetate, 2,5-dimethyl-2,
5-di(tert-butylperoxy)hexane, 2,
5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3, tert-butyl peroxylaurate, tert-butyl peroxymale acid, tert-butyl peroxybenzoate, methyl ethyl ketone peroxide, dichloromethane Examples include mil peroxide, cyclohexanone peroxide, tert-butylcumyl peroxide, 2,5-dimethylhexanone 2,5-dihydroperoxide, and the like. These organic peroxides may be used alone or in combination of two or more. The blending ratio of the crystalline polyolefin resin and the modifier, an organic silane compound having an ethylenically unsaturated bond, and an organic peroxide, varies depending on the desired MFR of the modified polyolefin, etc.
Generally, the modifier is 0.01 to 5 parts by weight, especially 0.1 parts by weight, per 100 parts by weight of the crystalline polyolefin resin.
-3 parts by weight, and a range of 0.01 to 5 parts by weight, particularly 0.1 to 2 parts by weight of the organic peroxide is preferred. In addition, the blending ratio of the modifier and organic peroxide is
5 to 80 parts of organic peroxide per 100 parts by weight of modifier
Parts by weight ranges are preferred. The modified polyolefin used in the present invention is prepared by a method known per se from a crystalline polyolefin resin, a modifier, and more preferably an organic peroxide, preferably under conditions in which the organic peroxide does not decompose. , the crystalline polyolefin resin, the modifier, and the organic peroxide are mixed by applying a known suitable mixing method, and the resulting mixture is heated to a temperature at which the polyolefin resin melts but does not decompose, preferably about
It is obtained by heating and reacting at a temperature of 180 to 260°C, particularly 220 to 250°C. The simplest heat treatment operation is to melt and heat the mixture in an extruder at the above temperature for about 2 to 5 minutes. The modified polyolefin obtained as described above has an MFR of 1 to 150 g/10 min, particularly 10 to 50 g/10 min.
Preferably. Powdered calcium carbonate (heavy,
As for light particles, the particle size is 0.05~10μ, especially 0.05~10μ.
2μ is preferable. Although calcium carbonate may be surface-treated, it is preferably not surface-treated. Furthermore, examples of the unmodified crystalline polyolefin resin used in this invention include the above-mentioned crystalline polyolefin resins. Unmodified crystalline polyolefin resin has an MFR of 0.1 to 10 g/10 min, especially 0.3 to 10 min.
5 g/10 min is preferred, and the same type as used to obtain the modified polyolefin is preferably used. In particular, the above-mentioned crystalline propylene polymer is used as the unmodified crystalline polyolefin resin. Conventionally known additives (antioxidants, ultraviolet absorbers, etc.) may be blended with the unmodified crystalline polyolefin resin. The powdered inorganic substance and modified polyolefin may each be used in the form of a master batch of unmodified crystalline polyolefin resin. The adhesive polyolefin composition used in the present invention comprises the modified polyolefin, powdered calcium carbonate, and unmodified crystalline polyolefin resin in a blending ratio of (a): modified polyolefin 10 to 80% by weight, (b): 5-50% by weight of powdered calcium carbonate, preferably 10-50% by weight,
and (c): unmodified crystalline polyolefin resin 10
It can be obtained by mixing to 80% by weight (total 100% by weight). When mixing,
Furthermore, various additives, such as weathering (thermal) stabilizers,
Molding aids, other inorganic or organic fillers, conductive fillers, etc. may also be added. The simplest mixing operation is to mix each of the above components at approximately 180-260°C, especially at 220-260°C.
The mixture is melt-mixed in an extruder at a temperature of 250°C for about 1 to 10 minutes. Examples of the extruder include a single-screw or twin-screw extruder and a continuous mixer such as FCM. The effect of the present invention is further improved by performing a deaeration operation (venting) during melt-mixing.
This is because there is moisture attached to the surface of the powdered inorganic substance. The laminate of the present invention comprises the modified polyolefin 10
~80% by weight and unmodified crystalline polyolefin resin
A metal layer and a polymer layer are present through an adhesive layer with a thickness of 1μ or more, which is made of an adhesive polyolefin composition of 10 to 80% by weight and 5 to 50% by weight of a powdered inorganic substance (total 100% by weight). It includes everything that exists. For example, metal layer/adhesive layer/polymer layer, polymer layer/adhesive layer/metal layer/adhesive layer/polymer layer,
Laminates such as metal layer/adhesive layer/polymer layer/adhesive layer/metal layer are suitable. The laminate of the present invention has high adhesion strength even when using not only degreased metal but also non-degreased metal such as undegreased chrome-plated steel plate, stainless steel, etc. as a metal layer, This is industrially extremely advantageous compared to adhesives based on polyolefin resins. In the laminate of the present invention, the adhesive polyolefin composition described above is interposed between the metal layer and the polymer layer, and the thickness of the adhesive layer formed thereby is 1 μm.
As mentioned above, it can be manufactured by heat-pressing so as to preferably have a thickness of 10 to 80μ. Suitably, an adhesive layer and a polymer layer (preferably thickness 0.1~
20mm) and a composite resin layer (the structure is an adhesive layer/
Polymer layer and adhesive layer/polymer layer/adhesive layer are preferred. ) is manufactured in advance, and the composite resin layer and metal layer (for example, a metal plate, the thickness is 0.1 to 20 mm in the case of a metal plate)
is preferred. ) by thermally welding them using a press, roll, etc., to produce a laminate.
At this time, the temperature is preferably higher than the softening point of the modified polyolefin, and the pressure is preferably 1 to 100 kg/cm ² . A composite resin layer of an adhesive layer and a polymer layer can be formed by coextrusion molding an adhesive polyolefin composition with the polymer layer so that the adhesive layer is preliminarily laminated on the surface of the polymer layer. By a method of laminating a film (which may be an extruded film) with a preformed sheet for forming a polymer layer, or a method of laminating a polymer layer extruded into a sheet with a preformed adhesive film. It can be obtained suitably. Various laminates can be continuously produced by the method of the present invention. For example, the method for continuously producing a laminate of metal plate/adhesive layer/polymer layer/adhesive layer/metal plate is as follows. The following methods can be mentioned. That is, metal plates of different or similar types (which may be degreased in advance by a method known per se) are preheated using a preheating device such as an oven or roll (preheating to a temperature higher than the melting temperature of the modified polyolefin) (preferably) and then feed these to a heating and pressing device such as a roll or steel belt. On the other hand, an adhesive film and a polymer sheet, which serve as an intermediate layer, are supplied between two metal plates either separately or as an integrated laminated sheet formed by laminating them in advance. The adhesive film may be preliminarily adhered to the surface of the metal plate. Metal plate - adhesive film -
It is preferable that five layers (polymer sheet, adhesive film, metal plate) are stacked one on top of the other, and heated and pressed using a heating and pressing device so that at least the surface portion of the adhesive film and the polymer sheet are melted. For crystalline polyolefin resin (for adhesive films or polymer sheets), the heating temperature is preferably about 170 to 270°C, particularly 180 to 240°C, and the pressing pressure is generally 1 to 240°C.
A laminate plate (metal composite plate) is produced by maintaining the pressure at 100 Kg/cm ² , particularly from 3 to 100 Kg/cm ² for about 5 seconds to 10 minutes. The thus produced laminate is cooled under pressure using a roll or the like. The temperature at this time is preferably a temperature equal to or lower than the crystallization temperature of the modified polyolefin. For example, when crystallized polypropylene resin (for adhesive films) is used, it is preferable to cool it under pressure to a temperature of about 110° C. or less. After being cooled under pressure to a temperature below the crystallization temperature of the modified polyolefin, it is cooled to room temperature. The laminate is then edge-trimmed with a slitter, if necessary, straightened with a leveler, and cut to the appropriate length in a cutting or winding process, or
It is rolled up and made into product laminates. The laminates obtained by the method of the present invention generally have a thickness of 0.2 to 20 mm, have high adhesive strength between metal plates, are lightweight compared to metal plates of the same thickness, and have good sound insulation and heat insulation properties. It has excellent cold workability such as cutting into various shapes, drilling, bending, and drawing. The laminate of the present invention can be used as interior and exterior materials for automobiles, building materials, industrial materials, and packaging materials. [Example] Next, an example will be shown. In the following description, parts indicate parts by weight, and melt flow rate (MFR) is
T-peel strength to indicate adhesion was measured according to ASTM D1238 and JIS K6854. Example 1 To 100 parts of powder of ethylene-propylene block copolymer (MFR 1.0 g/10 minutes, ethylene content 8% by weight, melting temperature about 160°C) [resin (1)],
As antioxidants, 0.1 part of Irganox 1010 (Musashino Geigy) and 0.2 part of Antiox S (Nippon Oil & Fats),
Calcium stearate 0.05 part, γ as a denaturing agent
- Blend 0.7 parts of methacryloyloxypropyltrimethoxysilane and 0.35 parts of tert-butyl peroxybenzoate as an organic peroxide, mix for 10 minutes with a Henschel mixer, and then use a 50 mmφ single screw extruder at 240°C for 2 minutes ( Residence time) Melt and heat to react, MFR25g/10 of about 2mmφ x 3mm
Pellets of modified polypropylene were obtained. This pellet and calcium carbonate (White SSB red,
Pellets of average particle size 1.25 μ, specific surface area 1.85 m ² /g, Shiroishi calcium) (charcoal) and ethylene-propylene block copolymer (MFR 1.0 g/10 min, ethylene content 8% by weight, melting temperature 160°C) (contains a known antioxidant, calcium stearate) in a blender at a ratio of 40 parts of modified polypropylene, 20 parts of calcium carbonate, and 40 parts of unmodified polypropylene, and then placed in a 50 mmφ vented single screw extruder. The mixture was melt-kneaded at 250° C. for 2 minutes, and then molded into a film (adhesive film) of the adhesive polyolefin composition with a thickness of 80 μm using a film molding machine. This film was used as an adhesive layer, a 0.47 mm thick sheet made of the resin (1) was used as a polymer layer, and an undegreased chrome-plated steel plate (0.2 mm thick x
Using two sheets (300mm x 300mm), use a compression molding machine to preheat at 180 to 220℃ for 5 minutes, pressurize for 3 minutes (surface pressure of 3Kg/cm2 ^or more), and then cool for 25 minutes (50℃).
A laminate with a five-layer structure was obtained by cooling slowly until the temperature reached 100. A test piece (width 25 mm) was cut from this laminate and the adhesive strength was determined at a peeling rate of 20 cm/min. The results are summarized in Table 1. Example 2 A laminate was obtained by thinning the adhesive layer in Example 1 from 80μ to 40μ and increasing the thickness of the polymer layer accordingly. The results are shown in Table 1. Example 3 A laminate was obtained in the same manner as in Example 1, except that the type of metal plate was changed from a steel plate to an undegreased stainless steel plate (SUS304, thickness 0.15 mm). The results are shown in Table 1. Example 4 Metasol H-400 [alkaline degreasing agent, Marubishi Yuka Kogyo Co., Ltd.] at 70 to 80°C was used instead of an undegreased steel plate as a metal plate.
A laminate was obtained in the same manner as in Example 1, except that a degreased chrome-plated steel plate was used, which had been immersed in a 3% aqueous solution of Co., Ltd. for 5 minutes, washed with water, and degreased. The results are shown in Table 1. Example 5 A laminate was obtained in the same manner as in Example 1, except that 80 parts of resin (1) and 20 parts of calcium carbonate were mixed and formed into a sheet as the polymer layer.
The results are shown in Table 1. Comparative Example 1 A laminate was obtained in the same manner as in Example 1, except that a film made only of modified polypropylene was used in place of the adhesive polyolefin composition film (adhesive film). The results are shown in Table 1. Comparative Example 2 The same procedure as in Example 1 was carried out except that 80 parts by weight of modified polypropylene and 20 parts by weight of calcium carbonate were blended instead of using unmodified crystalline polypropylene in the adhesive layer composition. The T-peel strength was 5.9 (Kg/cm) and the failure mode was interfacial failure. Comparative Example 3 Example 1 except that talc was used instead of calcium carbonate in the adhesive layer composition in Example 1.
I went in the same way. The T-peel strength was 2.4 (Kg/cm). Comparative Example 4 The same procedure as in Example 1 was carried out except that the adhesive layer composition used was a composition excluding calcium carbonate. The T-peel strength was 1.0 (Kg/cm) or less. Comparative Example 5 The same procedure as in Example 1 was carried out except that barium sulfate was used instead of calcium carbonate in the adhesive layer composition. The T-peel strength was 2.1 (Kg/cm).

【table】

〔Effect of the invention〕

As described above, according to the present invention, a laminate with high adhesive strength can be obtained.

Claims (1)

[Claims] 1. The metal layer and the polymer layer are made of 10 to 80% by weight of a modified polyolefin obtained by graft-modifying a crystalline polyolefin resin with an organic silane compound having an ethylenically unsaturated bond under heating. 10-80% by weight of unmodified crystalline polyolefin resin and 5-50% by weight of powdered calcium carbonate (100% by weight in total)
The thickness is made of adhesive polyolefin composition with
A laminate made by laminating layers with a uniform adhesive layer of 1μ or more. 2 Between the metal layer and the polymer layer, 10 to 80% by weight of a modified polyolefin obtained by graft-modifying a crystalline polyolefin resin with an organic silane compound having an ethylenically unsaturated bond under heating and unmodified crystals. An adhesive polyolefin composition of 10 to 80% by weight of a polyolefin resin and 5 to 50% by weight of powdered calcium carbonate (100% by weight in total) is interposed, and the thickness of the adhesive layer formed thereby is 1 μm.
A method for producing a laminate, characterized by carrying out heat and pressure bonding so as to achieve the above. 3. Production of a laminate according to claim 2, in which an adhesive layer is preliminarily laminated on the surface of a polymer layer by coextrusion molding an adhesive polyolefin composition with a polymer layer, and then subjected to adhesion with a metal layer. Law. 4. The method for producing a laminate according to claim 2, wherein an adhesive film made of an adhesive polyolefin composition is laminated with a preformed sheet for forming a polymer layer, and then the adhesive film is bonded to a metal layer. 5. The method for producing a laminate according to claim 2, wherein the polymer layer extruded into a sheet is laminated with a pre-formed adhesive film and then bonded to a metal layer.