JPS6312785B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a laminate of metal and polyolefin.

Due to its inherent properties, polyolefin has been widely used for lining steel pipes, drums, etc., coating electric wires, machinery and equipment, and protecting glass. Particularly, metal surfaces such as iron and aluminum are frequently coated, and various processing methods have been proposed.

However, polyolefins such as polyethylene, polypropylene, and polybutene do not have polar parts, such as functional groups, in their molecules and are highly crystalline, so they have extremely poor adhesion to iron, aluminum, etc. This was the biggest difficulty in doing so.

Various attempts have been made to improve this adhesiveness. For example, methods have been proposed to treat the adhesive surface of polyolefin with solvent treatment, flame treatment, heated air treatment, oxidation treatment, etc., or methods to mechanically roughen or surface oxidize the metal surface to be bonded. ing.

However, all of these methods not only require complicated processing operations, but also fail to provide sufficient adhesive strength. Furthermore, even if sufficient adhesive strength is obtained, if it comes into contact with an aqueous solution containing electrolytes such as seawater or saline, the adhesive strength will decrease and rust will occur within a short period of time, resulting in peeling from the adhesive surface or Since a phenomenon in which the resistance to impact decreased was observed, it was unsuitable for applications requiring salt water resistance.

The present invention provides a method for producing a laminate of metal and polyolefin that not only has sufficient adhesive strength but also has excellent water resistance, especially salt water resistance.

That is, the gist of the present invention is to react an unsaturated polycarboxylic acid or a derivative thereof and a monoepoxy compound or a derivative thereof with a hydrocarbon polymer having at least one active hydrogen at the end and having 60% or more of the main chain saturated. The present invention relates to a method for producing a laminate of a metal and a polyolefin, which comprises interposing an isocyanate compound between the metal and a polyolefin composition prepared by blending a polyolefin with a polyolefin, and fusing the composition to the metal.

The present invention will be explained in more detail below.

The polyolefin composition in the present invention is formed by blending a special polymer and a polyolefin, which will be described later.Specifically, the polyolefin includes the following, for example.

Polymers and copolymers of α-olefins represented by ethylene, propylene, budene, 4-methylpentene-1, etc., ranging from relatively low molecular weight polymers to high molecular weight polymers. Their densities range from low density products of about 0.86 to high density products of about 0.97, and range from substantially amorphous to highly crystalline.

Taking polyethylene as an example, there are low-density homopolymers with many long chain branches produced by high-pressure methods, copolymers of ethylene with vinyl acetate, acrylic acid, methacrylic acid, acrylates, methacrylates, etc., and low-pressure methods. Examples include high-density polyethylene or copolymers of ethylene and other olefins produced by a method such as high-density polyethylene or copolymers of ethylene and other olefins produced by a medium-pressure method.

Regarding polypropylene, it includes stereoregular polypropylene, that is, isotactic polypropylene, syndiotactic polypropylene with high crystallinity, and atactic polypropylene with low crystallinity.

Polymers of olefins higher than propylene include polymers of butene-1, which also include polymers ranging from crystalline polymers with high stereoregularity to non-crystalline polymers. Furthermore, examples of higher olefin polymers include poly-4-methylpentene-1. In addition, there are no restrictions on the type of α-olefin, and various olefin polymers can be used.

Copolymers of ethylene and propylene, ethylene and butene-1, and ethylene and hexene-1 are also used, and in this case, any copolymer such as a random copolymer or a block copolymer may be used. Ethylene-propylene rubber obtained by polymerization in the presence of a system catalyst, and in some cases, a ternary copolymer with additional unsaturated components such as dicyclopentadiene, ethylidenenorponene, or 1,4-hexadiene. Also includes merging. Among these various polyolefins, usually
Low-pressure or high-pressure polyethylene or a mixture of high-pressure polyethylene and synthetic rubber is used.

The hydrocarbon polymer with a saturated main chain having at least one active hydrogen at the end, which is a raw material for the special polymer blended into the above-mentioned polyolefin, is as follows.

This polymer has at least one terminal active hydrogen group such as a hydroxyl group, a carboxyl group, an imino group, a mercapto group, an amino group, has a molecular weight of preferably about 500 to 200,000, and is liquid at room temperature.
Includes semi-solid and solid polymers. These polymers are usually obtained by hydrogenating diene-based polymers produced from dienes by various well-known methods, such as radical polymerization and anionic polymerization. However, in the case of anionic polymerization, depending on the conditions, the main amount, for example, 50% or more, especially 70
% or more of vinyl groups and whose main chain is saturated, ie 1,2 polybutadiene, which does not require further hydrogenation.

In the case of radical polymerization, the type of functional group containing active hydrogen varies depending on the polymerization conditions, such as hydrogen peroxide (see Japanese Patent Publication No. 42-22048) or azobiscyanoic acid (see Japanese Patent Publication No. 43-28474).
When used as a polymerization initiator, a hydroxyl group,
A polymer having carboxyl groups is obtained.

In order to obtain a polymer having a hydroxyl group at the terminal by an anionic polymerization method, for example, a monoepoxy compound, formaldehyde, acetaldehyde or acetone (Japanese Patent Publication No. 37-8190
(see publication), or halogenoalkylene oxide,
Polyepoxide or monoepoxide (JP-A-Sho
48-28595, JP-A No. 49-30469).

In addition, the living polymer here is produced by polymerizing a conjugated diene alone or a conjugated diene and a vinyl monomer using an anionic polymerization catalyst, such as an alkali metal or an organic alkali metal compound, according to a well-known method. A polymer having a structure in which an alkali metal is bonded to at least one of its ends. On the other hand, in order to obtain a product having a carboxyl group at the end, for example, carbon dioxide
342), or an epoxy compound followed by a polycarboxylic anhydride (JP-A-48-64193, JP-A-48
-96689, JP-A-48-96635) may be reacted. Furthermore, a polymer having terminal mercapto groups can be produced by reacting a living polymer with sulfur or carbon disulfide.

At least one type of conjugated diene monomer is used as a raw material monomer for these polymers.
As the conjugated diene monomer, butadiene-1,
3. Isoprene, chloroprene, pentadiene-
1,3,2,3-dimethylbutadiene-1,3,
Examples include 1-phenylbutadiene-1,3. On the other hand, as a copolymerization component of the conjugated diene copolymer, one or more vinyl monomers are used depending on the purpose. These vinyl monomers include vinyl aromatic compounds such as styrene, α-methylstyrene, and vinyltoluene; (meth)acrylic acid derivatives such as methyl acrylate, butyl acrylate, and methyl methacrylate; nitrile compounds such as acrylonitrile and methacrylonitrile;
Vinyl pyridines such as 2-vinylpyridine and 4-vinylpyridine; vinyl ethers such as methyl vinyl ether and 2-chloroethyl vinyl ether; vinyl halides such as vinyl chloride and vinyl bromide; and vinyl esters such as vinyl acetate. Furthermore, vinyl monomers having active hydrogen such as 2-hydroxyethyl methacrylate, acrylic acid, and acrylamide can also be used. When used in combination with a conjugated diene monomer, the amount of vinyl monomer used is preferably 50% by weight or less based on the total monomer amount, considering the physical properties of the final target product.

The unsaturated double bonds in the main chain of these diene polymers and/or diene copolymers are used after being completely or partially hydrogenated. However, in the case of polybutadiene with 1,2 bonds and polyisoprene polymer with 3,4 bonds, which do not substantially contain unsaturated bonds in the main chain, they can be used as they are. The above hydrogenation may be complete hydrogenation saturation or partial hydrogenation. However, for 1,4-polybutadiene, the hydrogenation percentage is at least 20%, preferably at least 30%. Hydrogenation rate
If it is less than 20%, the adhesiveness will be insufficient, and even if there is some adhesiveness, the adhesive surface will be uneven, which is not preferable. Since 1,4 polybutadiene has 50% carbon atoms involved in double bonds in its main chain, it is necessary to reduce this to 40% or less in the present invention. Moreover, as already mentioned above, for example, 1,
1,2 polybutadiene with 50% 2 bonds has 2 bonds in the main chain.
Since only 33% of the carbon atoms involved in heavy bonds are present, this product can be used as is in the present invention without any particular hydrogenation.

For the hydrogenation, commonly used catalytic hydrogenation means can be employed. That is, as the hydrogenation catalyst, a nickel catalyst (for example, Raney nickel), a cobalt, platinum, palladium, ruthenium, or rhodium catalyst, which has been used for a long time, or a mixture or alloy catalyst thereof can be used. These catalysts can be used alone, as solid or soluble homogeneous complexes, or supported on carbon, silica, diatomaceous earth, and the like. Furthermore, hydrogenation may be performed using a metal complex obtained by reducing a compound containing nickel, titanium, cobalt, etc. with an organometallic compound (for example, trialkylaluminum, alkyllithium, etc.). Molecular hydrogen is usually used as hydrogen, but hydrogen-containing gas can also be used as long as it does not contain substances that poison the catalyst. The hydrogen pressure can be either normal pressure blowing or pressurized system. Temperature is room temperature to 200℃, preferably
The temperature is below 150℃. The polyhydroxydiene polymer can be used alone or as a solution in a solvent. As such solvents, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, alcohols, aliphatic carboxylic acids, etc. can be used alone or in a mixed system.

Other methods for producing saturated hydrocarbon polymers having active hydrogen at their terminals include a method in which a copolymer of α-olefin and another monomer is oxidized and decomposed, and then reduced. For example, polyhydroxypolyisobutylene can be obtained by subjecting a butyl rubber-based polymer obtained by cationic polymerization of isobutylene and butadiene or 1,3-pentadiene to ozone decomposition treatment, and then reducing it with lithium aluminum hydrite. In addition, poly-α- containing unsaturated bonds obtained by copolymerizing ethylene alone or with dienes in the coexistence with propylene
Polyhydroxypolyolefin is obtained by subjecting olefin to ozonolysis treatment and then reducing it.

In the present invention, the unsaturated polycarboxylic acid or its derivative to be reacted with the above-mentioned polymer having active hydrogen at its terminal includes, for example, the following.

This includes unsaturated dicarboxylic acids and their derivatives having radical polymerizability (or copolymerizability), and specifically includes maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, Examples include norbornene-5,6-dicarboxylic acid, anhydrides, acid halides, and (di- or mono)alkyl esters thereof. These may be used alone or at the same time,
At the same time, a portion of saturated polycarboxylic acid and its derivatives may also be used in combination.

In the present invention, the other component to be reacted with the above-mentioned polymer having active hydrogen at its terminal is a monoepoxy compound or a derivative thereof. Polyepoxy compounds are not preferred because they cause gelation during the reaction. Examples of the above derivatives include glycols which are hydration products of monoepoxy compounds.

Examples of the monoepoxy compound include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, cyclohexene oxide, phenyl glycidyl ether, aryl glycidyl ether, glycidyl acrylate, and glycidyl methacrylate. One or more of these may be used simultaneously.

The amount of the unsaturated polycarboxylic acid or its derivative and the monoepoxy compound or its derivative to be reacted with the polymer having active hydrogen at the terminal is not particularly limited, and depends on the type of functional group having active hydrogen in the raw material polymer and the amount obtained. It is selected as appropriate depending on the physical properties required of the polymer, the type of functional group, etc. For example, when using a raw material polymer with a hydroxyl group at the end and desiring the resulting polymer to have a carboxyl group at the end, use an excess of unsaturated polycarboxylic acid or its derivative relative to the monoepoxy compound or its derivative. Just use it.

The reaction is carried out by adding two components, an unsaturated polycarboxylic acid or its derivative and a monoepoxy compound or its derivative, to a main chain saturated hydrocarbon polymer having at least one active hydrogen at the end, in the presence of a catalyst, or It is sufficient to heat it in its absence. In this case, as a catalyst, tertiary amine, quaternary ammonium compound, alkali metal, alkaline earth metal salt, hydroxide, and other usual esterification catalysts and ring-opening polymerization catalysts are used. Further, the reaction temperature is not particularly limited, but is preferably 50°C or higher. However, if the temperature is too high, side reactions such as gelation occur, which is undesirable, and if the temperature is too low, the reaction rate decreases, which is disadvantageous from an industrial standpoint. Therefore, a temperature of 80 to 150°C is preferred.

Further, when an acid anhydride is used as the unsaturated carboxylic acid or its derivative, and a monoepoxy compound is used as the monoepoxy compound or its derivative, sufficient reaction can be achieved simply by mixing and heating these raw materials. However, when using a free acid or ester as an unsaturated polycarboxylic acid or its derivative, or a glycol as a monoepoxy compound or its derivative, water or alcohol generated by the reaction must be removed from the reaction system. It is advantageous to carry out the reaction under such conditions.

In the present invention, a low molecular weight polyester is produced by reacting the unsaturated polycarboxylic acid or its derivative with a monoepoxy compound or its derivative in advance, and this is esterified with a polymer having active hydrogen at the terminal under dehydration conditions. A modified method of reacting can also be adopted. As another method, an unsaturated carboxylic acid or its derivative and a monoepoxy compound or its derivative can be reacted sequentially to a polymer having active hydrogen at the terminal. The polymer derivative obtained in this way is produced by reacting the active hydrogen at the terminal of the saturated hydrocarbon polymer in the main chain with an unsaturated polycarboxylic acid or its derivative and a monoepoxy compound or its derivative, resulting in one or more terminal active hydrogens. It forms an ester block.

To give an example of this polyester block formation, for example, when a hydrogenated product of polyhydroxypolybutadiene is reacted with maleic anhydride and epichlorohydrin in a ratio of 1:n:n in terms of hydroxyl group equivalents, a polymer mainly having a polyester block as shown in the following formula is formed. A derivative is obtained.

If the amount (molar amount) of maleic anhydride is greater than that of epichlorohydrin, the maleic anhydride will further react to form a carboxyl group at the end.

(The formula represents a polyhydroxy saturated hydrocarbon polymer residue, n represents an integer of 1 or more, and increases as the amount of maleic anhydride and epichlorohydrin increases.) Therefore, the polymer represented by the above formula In the derivative, the ratio of the polyester unit part to the part is 100 parts by weight of the former and 5 to 100 parts by weight of the latter.
Parts by weight ranges are preferred.

The hydrocarbon polymer derivative with a saturated main chain obtained as described above can be blended into a polyolefin and uniformly dispersed and mixed in the following manner.

As the mixing device, any conventional kneading device can be used, such as a Brabender blastograph, an extruder, a high-power screw kneader, or a roll. Although the temperature depends on the type of raw material, for example, in the case of high-density polyethylene, it can be carried out at 150 to 250°C. The mixing ratio is selected to effectively exhibit the properties of the resulting composition, but usually the above polymer derivative is added to 100 parts by weight of the polyolefin.
It is selected from the range of 0.05 to 10 parts by weight, preferably 0.1 to 5 parts by weight.

It goes without saying that the polyolefin composition described above may further contain colorants, stabilizers, other additives, and fillers that are conventionally commonly used. Fillers include sand, natural silica such as quartz, synthetic silica manufactured by wet or dry methods,
Natural silicates such as kaolin, mica, talc, clay, and asbestos, synthetic silicates such as calcium silicate and aluminum silicate, metal oxides such as alumina and titania, calcium carbonate, calcium sulfate, and other metal powders such as aluminum and bronze; Carbon black or the like can be used. In addition,
In the aforementioned polymer having active hydrogen at its terminal end, there is no problem even if a diene polymer, vinyl polymer, etc. that do not contain active hydrogen coexist in part. These act merely as diluents or fillers without reacting with unsaturated polycarboxylic acids or derivatives thereof and monoepoxy compounds or derivatives thereof.

In the present invention, when such a polyolefin composition is fused to a metal, it is necessary to interpose an isocyanate compound between the two.

Such an isocyanate compound may be any compound having a normal isocyanate group, such as diphenylmethane diisocyanate and its derivatives.

As a specific example, a compound obtained by reacting glycerin with propylene oxide and further reacting this with diphenylmethane diisocyanate having twice the amount of hydroxyl groups can be used.

In addition to the above, isocyanate compounds having various structures can be used. Blocked isocyanate compounds in which the terminal NCO group is blocked with a phenolic hydroxyl group can also be used. Furthermore, when an organic silicon compound having a hydrolyzable group and a group reactive with isocyanate is added to the isocyanate compound, the salt water resistance is further improved.

Examples of such organic silicon compounds include those commonly used as silane coupling agents, such as γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, Examples include γ-ureadopropyltriethoxysilane. Of course, these may be used alone, or two or more may be mixed or reacted.

Note that among these organic silicon compounds, organic silicon compounds having an amino group have strong reactivity with isocyanate, and therefore, when blended with an isocyanate compound, the organic silicon compound may immediately react and gel. Therefore, it is preferable to use only a small amount of the organic silicon compound having an amino group, or to perform an operation to reduce the amino group in advance. For example, a mixture of γ-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane in a ratio of 1:1 to 1:2 and reacted at 70 to 80°C for 1 hour is used.

The amount of these organic silicon compounds added to the isocyanate compound varies slightly depending on the organic silicon compound used, but is 1 to 50 parts by weight based on 100 parts by weight of the isocyanate compound.

In the present invention, examples of the metal to be bonded to the polyolefin composition include iron, aluminum, tin, zinc, and alloys thereof. It is sufficient if the metal surface is clean, but blasting or chemical conversion treatment is more effective.

Several known methods can be used to fuse the polyolefin composition. Examples include powder coating methods such as electrostatic coating and fluidized dipping, methods of heat-sealing a polyolefin composition in the form of a film or sheet, and melt-extrusion coating of a polyolefin composition. In addition, an ordinary polyolefin layer can be further formed on the outer layer of the special polyolefin composition coating according to the present invention by a conventional method.

As detailed above, according to the present invention, it is possible to firmly adhere polyolefin and metal, and it is possible to obtain a laminate having excellent water resistance and salt water resistance.

Next, examples of the present invention and production examples (reference examples) of special polymers constituting the polyolefin composition used in the present invention will be explained, but the present invention is not limited to these examples unless the gist of the invention is exceeded. It is not something that is received.

Reference Example 1 Example of manufacturing a special polymer to be blended with polyolefin Polyhydroxypolybutadiene (R-45HT manufactured by Arco Chem,
n3110, [-OH] = 0.82meq/g, cis-1,4:
15%, trans-1,4: 58%, vinyl: 27%)
3Kg, cyclohexane 3Kg and carbon-supported ruthenium (5%) catalyst [manufactured by Nippon Engelhard Co., Ltd.]
After charging 300g and replacing the inside of the system with purified argon gas, high-purity hydrogen gas is started to be supplied into the autoclave, and heating is started at the same time. It took about 30 minutes for the inside of the autoclave to reach steady conditions (internal temperature 100°C, internal pressure 150 Kg/cm ³ ). After 15 hours under these conditions, the hydrogenation reaction was stopped, and the polymer was purified and dried according to a conventional method. As a result of analysis by infrared absorption spectrum, the obtained polymer was found to be a hydrocarbon polymer containing almost no double bonds. The amount of -OH groups in the hydrogenated product was 0.81 meq/g.

Adding 14.9 parts by weight of maleic anhydride, 0.18 parts by weight of N-N-dimethylbenzylamine, and 100 parts by weight of toluene to 100 parts by weight of the saturated hydrocarbon polymer having a hydroxyl group at the end produced by the above method,
After reacting the terminal hydroxyl group with maleic anhydride at 110°C for 3 hours, 70 parts by weight of epichlorohydrin was added and the mixture was reacted at 110°C for 4 hours. Then, add 35.2 parts by weight of epichlorohydrin and heat to 110°C.
After reacting for 3 hours, toluene was removed to produce a special polymer to be blended into polyolefin.

Reference Example 2 Production of Compound Having Isocyanate Group Three times the mole of diphenylmethane diisocyanate was mixed with G400 (manufactured by Sanyo Chemical Co., Ltd.), which is a reaction product of glycerin and propylene oxide. Then diluted with toluene to make a 30% solution and heated at 80°C.
The reaction was carried out for 2 hours to obtain the isocyanate compound used in the present invention.

Example 1 Commercially available high-density polyethylene (MI=0.2, ρ=
0.948) To 100 parts by weight, 0.5 parts by weight of the polymer obtained in Reference Example 1 was added and uniformly dispersed using a mixing roll to obtain a polyolefin composition having adhesive properties. On the other hand, to 100 parts by weight of the isocyanate compound obtained in Reference Example 2, 15 parts by weight of toluene, 15 parts by weight of ethyl acetate, and a silane coupling agent (γ-glycidoxypropyltrimethoxysilane, KBM403, Shin-Etsu Chemical ( Co., Ltd.) to 100 parts by weight of silane coupling agents (γ-aminopropyltriethoxysilane,
1100 (manufactured by Nippon Unica Co., Ltd.) was reacted at 70° C. for 2 hours, and 30 parts by weight of the mixture was mixed and applied to a blast-treated steel plate (1.6 mm thick). The coating was performed using a bar coater (#8), and the thickness of the coating film was 2 to 5 μm. Place a chip of the polyolefin composition on the surface-treated steel plate,
A polyolefin composition was fused onto the surface treated steel plate using a hot press. At this time, the heat press was at 240°C and the pressure fusion time was 15 minutes.
Furthermore, during pressure fusion using a hot press, a 5.2 mm spacer was used to define the thickness of the laminate.

After pressure fusion, the pressed pieces were taken out and cooled for 20 minutes in a cooling press (temperature set at 18°C), and then taken out from the cooling press to obtain a laminate. The thickness of the polyolefin layer of the obtained laminate was 3 mm. A sample with a length of 100 mm and a width of 25 mm was cut from this laminate and subjected to a 180°C peel test (using Tensilon, peeling speed of 50 mm/mm).
It was 27.3Kg/cm. Also length 90 from the same laminate
When a sample with a width of 20 mm was cut out and immersed in 3% saline at 60°C, no peeling between the polyolefin and the metal was observed even after 230 hours.

Comparative Example 1 A laminate was produced in the same manner as in Example 1, except that the polyolefin composition was directly fused to the blast-treated steel plate without applying an isocyanate compound, but the steel plate and polyolefin layer were easily attached by hand. Peeled off. The peel strength at this time is 1 to 5 kg/
It is about cm.

Comparative Example 2 Fusion was carried out in the same manner as in Example 1 except that the high-density polyethylene obtained in Reference Example 1 to which no polymer was added was used, but the steel plate and polyethylene were not bonded at all.

Claims (1)

[Claims] 1. A main chain having at least one active hydrogen at the end.
An isocyanate compound is interposed between the metal and a polyolefin composition prepared by blending a polyolefin with a polymer obtained by reacting an unsaturated polycarboxylic acid or its derivative and a monoepoxy compound or its derivative with a hydrocarbon polymer of which 60% or more is saturated. A method for producing a laminate of metal and polyolefin, which comprises fusing the composition to the metal through interposition. 2. A method for producing a laminate according to claim 1, characterized in that a hydrocarbon polymer whose main chain is substantially saturated is used. 3. The method for producing a laminate according to claim 1 or 2, wherein an organic silicon compound having a hydrolyzable group and a group reactive with isocyanate is blended with the isocyanate compound.