JPH022911B2 - - Google Patents

Description

[Detailed description of the invention]

Purpose of the invention (industrial application field) The present invention relates to a side protection molding (hereinafter referred to as
The present invention relates to a method for joining a molded article such as a polyolefin tape to a molded article such as a molding. (Prior art) Traditionally, polyethylene (PE), polypropylene (PP), poly-α-olefin, ethylene-propylene copolymer (EPM), ethylene-propylene-diene ternary copolymer (EPDM), etc. Polyolefin molded articles are effectively used in various fields, for example, in the automobile field, taking advantage of their light weight. (Problems to be Solved by the Invention) However, since polyolefin does not have a polar group in its molecules, even if an adhesive is applied to the molded product, the resulting coating film is likely to peel off. There is a point. Furthermore, when a polyolefin molded article is bonded to another adherend using an adhesive, the other adherend may undergo dimensional changes due to temperature changes or volatilization of plasticizers, etc., as with polyvinyl chloride moldings. Therefore, the polyolefin molded article is easily peeled off from other adherends. In order to solve this problem, various adhesives that exhibit adhesion to polyolefin molded articles have been proposed, but no adhesive with excellent adhesion has yet been found. As a result of intensive research aimed at developing adhesives with superior adhesive properties, the present invention was developed based on the results that a combination of a specific adhesive and a specific primer can bond a polyolefin molded article to another adherend. , discovered the fact that they can be bonded firmly, and completed the present invention. Structure of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention uses polyurethane having a hydroxyl group at the end, polyacrylic acid, a derivative thereof, polymethacrylic acid or a derivative thereof. An acrylic polyurethane adhesive consisting of at least one acrylic polymer is used as an adhesive for the polyolefin molded body, and a mixture of rubber, polyisocyanate and/or a halogenating agent is used as a primer on the polyolefin molded body side. We adopted technical means to do so. (Function) Since the primer applied to the polyolefin molded article contains a polyisocyanate and/or a halogenating agent, the primer exhibits an affinity for the polyolefin molded article and adheres to the polyolefin molded article. In addition, an acrylic polyurethane adhesive derived from polyurethane having a hydroxyl group at the end exhibits excellent adhesion to the primer, and due to the intermolecular force of the acrylic polymer in the acrylic polyurethane adhesive, The adhesive performance of the adhesive itself is improved. (Example) To explain an example embodying the present invention, first, a polyolefin molded body as an adherend is prepared. The polyolefin molded product may be of any type as long as it requires improved adhesion, but in the present invention, for example, the above-mentioned PE,
PP, chlorosulfonated polyethylene, poly-α
- Homogeneous polymers such as olefins, copolymers such as EPM and EPDM, mixed polymers containing these as main components with natural rubber, synthetic rubber, etc., or blends in which various additives are mixed with the polyolefins. is used. The polyolefin molded product may be of any shape as long as it can be bonded to another adherend using an adhesive in a solid state. There are inserts etc. used. These molded bodies can be obtained by methods such as extrusion molding, injection molding, press molding, and vacuum forming. On the other hand, other adherends include coated or uncoated various rubbers, ABS, polyvinyl chloride, polyamide moldings or foams, metal products, wood products, textile products, etc. that have polar groups. However, depending on the application, polyolefin molded products can also be used. Another preferred adherend is polyvinyl chloride molding. Next, an adhesive according to the present invention is prepared. This adhesive is an acrylic polyurethane adhesive consisting of polyurethane having a hydroxyl group at the end and an acrylic polymer, and is produced by any one of the following methods. The first method is to mix 10 to 500 parts by weight of an acrylic polymer to 100 parts by weight of polyurethane having a hydroxyl group at the end to form a homogeneous solution (polymer method). This is a method (monomer method) in which 10 to 500 parts by weight of an acrylic monomer is polymerized in the presence of 100 parts by weight of polyurethane having a hydroxyl group at the end and about 0.05 parts by weight of a polymerization initiator such as benzoyl peroxide. . Polyurethane having a hydroxyl group at the end is produced by first producing a polyurethane prepolymer by reacting a polyisocyanate and a polyol or polyester polyol in an excess molar amount of the former at 80°C for 3 hours in a dry nitrogen gas atmosphere. It is obtained by adding a polyol to a prepolymer and causing a chain extension reaction. In this reaction, aliphatic hydrocarbons such as n-hexane and cyclohexane, aromatic hydrocarbons such as benzene, ethylbenzene, toluene and xylene, ketones such as acetone, methyl ethyl ketone, ethyl propyl ketone and methyl butyl ketone, ethers such as tetrahydrofuran, Acetic esters such as methyl acetate, ethyl acetate, isopropyl acetate, halogenated hydrocarbons such as methylene chloride, 1,1,1-trichloroethane, trichloroethylene, sole solvents such as dimethyl sulfoxide (DMSO), dimethyl formamide, etc. Mixed solvents are used. The polyisocyanate includes tolylene diisocyanate (TDI), 1,5-naphthalene diisocyanate, xylylene diisocyanate (XDI), 4,4'-diphenylmethane diisocyanate (MDI), and 4,4',4''-triphenylmethane. Aromatic polyisocyanates such as triisocyanate (TPMI) and isophorone diisocyanate,
4,4′-methylenebis(cyclohexyl isocyanate (H-MDI), alicyclic polyisocyanate such as hexahydroxylylene diisocyanate,
Aliphatic polyisocyanates such as 1,6-hexamethylene diisocyanate, trimethylolpropane tolylene diisocyanate 3 mole adduct (TMP-3TDI), trimethylolpropane tolylene diisocyanate 3 mole adduct (TMP-
3IPDI), 4,4′- for polyalkylene oxide glycols such as polypropylene glycol
2-mole adducts of diphenylmethane diisocyanate or tolylene diisocyanate, other adducts of glycerin and pentaerythritol to polyisocyanates, terminals of tris(P-isocyanate phenyl) thiophosphate, etc.
Compounds with NCO groups are used. In addition, the polyols include ethylene glycol, propylene glycol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol (1,4-BD), 1,5-pentanediol (1,5 -PD), 1,6-hexanediol (1,6-HD), trimethylolpropane (TMP), 2,2,4-trimethylpentane-1,
Aliphatic polyols such as 3-diol, 2-ethyl-1,6-hexanediol, neopentyl glycol, alicyclic glycols such as bicyclohexyl glycol, diethylene glycol, dipropylene glycol, triethylene glycol, poly(propylene oxide) glycol Polyester polyols such as poly(alkylene oxide) glycols such as poly(tetramethylene oxide) glycol (PPG), poly(ethylene adipate) glycol (PEAG), and poly(butylene adipate) glycol (PBAG) can be used. The polyester polyol is obtained by reacting a polycarboxylic acid with the polyol in an excess molar amount relative to the polycarboxylic acid. As the polycarboxylic acid, aromatic polycarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, and aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid are used. The polyester polyol used has a molecular weight of 500 to 5,000, preferably 1,000 to 3,000. Acrylic polymers include polyacrylic acid and its derivatives, polymethacrylic acid and its derivatives, and preferably they contain active hydrogen. Monomers used in the production of the acrylic acid derivatives include methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate,
Alkyl acrylates such as lauryl acrylate, 2-ethylhexyl acrylate, iso-butyl acrylate, isodecyl acrylate, 2-
Examples include hydroxyalkyl acrylates such as hydroxyethyl acrylate, aminoalkyl acrylates such as aminoethyl acrylate, and dimethylaminoethyl acrylate. When a monomer having no active hydrogen is used as the monomer, acrylic acid, methacrylic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, the above-mentioned hydroxyalkyl acrylate, etc. are copolymerized. In addition, raw materials for polymethacrylic acid derivatives include alkyl methacrylates such as methyl methacrylate (MMA), ethyl methacrylate, n-propyl methacrylate (PMA), n-butyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, and iso-butyl methacrylate; There are methacrylic acid derivatives such as hydroxyalkyl methacrylates such as -hydroxypropyl methacrylate, aminoalkyl methacrylates such as aminoethyl methacrylate, and dimethylaminoethyl methacrylate. The vinyl compound having active hydrogen used in the copolymerization is the same as described above. The adhesive of this example contains 5 to 60 parts by weight of an organic solvent used in the production of polyurethane per 100 parts by weight of solid components. This adhesive has a hydroxyl group at the end and reacts with the primer, but to further improve adhesiveness, polyisocyanate must be added at a ratio of 50 parts by weight or less to 100 parts by weight of the acrylic polyurethane adhesive. Can be done. Next, 0.1 to 50 parts by weight of polyisocyanate and 0.002 to 20 parts by weight of halogenating agent are added to 100 parts by weight of rubber.
Prepare primers that are mixed in parts by weight. The rubbers include natural rubber (NR), styrene-butadiene rubber (SBR), butadiene rubber (BR), isoprene rubber (IR), butyl rubber (IIR), chloroprene rubber (CR), nitrile rubber (NR), EPM, and EPDM. , acrylic rubber (ACM),
Various natural and synthetic rubbers such as chlorosulfonated rubber are used. These rubbers may also contain known additives such as vulcanizing agents, vulcanization accelerators, anti-aging agents, fillers, plasticizers and the like. As the polyisocyanate, those mentioned above as raw materials for polyurethane are used. As the halogenating agent, alkyl hypochloride, t-butyl hypochloride (t-BHC),
The most preferred halogenated compounds are hypohalites and compounds having a -CONX- bond in the molecule (X means a halogen atom) such as N-bromosuccinimide (NBSI) and trichloroisocyanuric acid (TCIA). In addition, antimony pentafluoride, a mixed solution of sulfur fluoride and bromine, a mixed solution of iodine and potassium iodide, a mixed solution of halogen oxygen salt and concentrated hydrochloric acid, and alkali bromination. and peroxodisulfuric acid. The primer of this example is obtained by mixing the above-mentioned rubber, an isocyanate and/or a halogenating agent in the above-mentioned organic solvent, and is applied to a polyolefin molded article. After that, the adhesive is applied, and by volatilizing the solvent, the adhesive of this example exhibits its original adhesive performance. Experimental Example 1 Next, the effects of this example will be explained based on a specific experimental example. This experimental example shows the adhesion performance of a polyolefin molded article by combining the adhesive of the present invention and a primer. First, a test piece with a width of 40 mm and a length of 150 mm, with an insert having a curved surface with a radius of curvature of 20 mm, was formed from PP, and after applying various primers and adhesives to the insert, the results shown in Table 1 were prepared. The polyvinyl chloride composition was injection molded at 200°C to obtain a molded product. After leaving this molded product in an atmosphere at 80°C for 100 hours, we measured how much the molded part of the polyvinyl chloride resin shifted with respect to the curved surface. An experiment was conducted to determine whether a combination of such an adhesive and a primer would exhibit excellent adhesive performance.

[Table] Polyurethane having the components and composition shown in Table 2 was used in this experiment. In addition, the symbols of raw materials in Table 2 mean the above-mentioned raw materials, and the numbers of polyols mean molecular weights. Also, the numbers in parentheses mean parts by weight. In the table below, the same meanings as above apply.

【table】

[Table] Acrylic polyurethanes (reaction mixtures) were produced from the polyurethanes having terminal hydroxyl groups listed in Table 2 and the acrylic polymers listed in Table 3.

【table】

[Table] Meaning.
In the monomer method shown in the above table, 0.05 parts by weight of benzoyl peroxide was used as a polymerization initiator. Various acrylic polyurethanes shown in sample numbers a to k listed in Table 3 are mixed with a mixed solvent of 1,1,1-trichloroethane:toluene=100:60 (weight ratio) to achieve a solid content of 35 Adjusted weight percent adhesive. Next, the SBR type and
EPDM rubber was dissolved in toluene in an amount of 10% by weight.

【table】

[Table] Primers were prepared by mixing polyisocyanate in various proportions based on 100 parts by weight of rubber into these four types of rubber solutions. Then, combine the primer with the acrylic polyurethane listed in Table 3 to form an adherend.
Table 6 shows the results of evaluating the adhesive performance for PP inserts. In Table 6, the XX mark indicates that the adhesion performance is poor due to displacement of the polyvinyl chloride molded product as another adherend on the curved surface of the PP insert, and the XX mark indicates that the curing speed is low and the adhesion is poor. Indicates a case where the performance is slightly poor, and a circle indicates a case where the curing speed is fast and there is no deviation on the curved surface. 7th below
The same applies to tables. Similarly, add 100% of rubber to the above four rubber solutions.
Primers were prepared by mixing halogenating agents based on parts by weight. Table 7 shows the results of evaluating the adhesive performance of the primer in combination with the acrylic polyurethane listed in Table 3.

【table】

[Table] As can be seen from Tables 6 and 7, when the primer of the present invention is combined with an adhesive, the adhesion performance to polyolefin molded articles is significantly improved. Further, excellent adhesive performance is obtained when the polyisocyanate is used in an amount of 0.1 to 50 parts by weight and the halogenating agent is used in an amount of 0.002 to 20 parts by weight based on 100 weight parts of rubber. Experimental Example 2 An experimental example in which the present invention was embodied in a method of bonding a tape having an adhesive layer on one side to the back side of a molding made of polyvinyl chloride as a polyolefin molded body will be shown. In this example, a primer containing polyisocyanate was used. First, an acrylic polyurethane adhesive, a primer, and two adherends, a molding and a tape, were prepared. The acrylic polyurethane adhesive listed in Table 3 of Experimental Example 1 was used, and the primer was prepared from the rubber listed in Tables 4 and 5 and the polyisocyanate listed in Table 8. The mold was obtained by extrusion molding at 170° C. the same polyvinyl chloride composition as listed in Table 1 except that the degree of polymerization was 1450 and 80 parts by weight of dioctyl phthalate was contained. After applying an acrylic polyurethane adhesive to the back side of the molding to form an adhesive layer, the adhesive layer was air-dried for 30 minutes at room temperature. A tape was bonded to this adhesive layer. The base of this tape is made of 5x expanded PE foam, and
An adhesive layer made of the acrylic polyurethane adhesive was formed on the primer layer. The bonded body was left at room temperature for 3 days with both of the adhesive layers bonded to each other. Then, a shear test was conducted in which the tape was peeled off from the molding at a speed of 30 mm/min. The results are shown in Table 8. As shown in the figure, the molding 2 is attached to the metal plate 1 via the adhesive layer 3, primer 4, tape 5, and adhesive layer 5a.
It can be attached to.

[Table] As is clear from Table 8, the method of the present invention, which uses an acrylic polyurethane adhesive as the adhesive and a mixture of rubber and polyisocyanate as the primer, has superior adhesive properties. In particular, when the amount of polyisocyanate deviates from a certain range, the shear stress, that is, the adhesive performance decreases (Experiment Nos. 4 and 8). Experimental Example 3 An experimental example embodying the present invention is shown in which the amount of the chain extender is varied and a primer containing a halogenating agent is used. An adhesive performance experiment was conducted in the same manner as in Experimental Example 2, in which a molding was formed from a polyvinyl chloride composition and a PE tape as an adherend was adhered to the molding. However, as the acrylic polyurethane adhesive, the acrylic polyurethane adhesive of Experimental Example 2 was used except that only the polyurethane was changed to the one listed in Table 9. Table 10 shows the results of the adhesion performance experiment.

【table】

【table】

[Table] As is clear from Table 10, even when a primer containing a halogenating agent is used, good adhesion performance is shown for PE tape. In particular, when the amount of halogenating agent is too little or too much, the shear stress decreases (Experiment Nos. 4, 5, and 8). The same holds true for the adhesive performance of polyisocyanate (Experiment No. 11).

【table】

[Table] The present invention is not limited to the above examples, and for example, polyisocyanate can be added to an acrylic polyurethane adhesive. Effects of the Invention As detailed above, the present invention exhibits the excellent effect that other adherends can be firmly adhered to a polyolefin molded article having no polar groups.

[Brief explanation of drawings]

The figure is a cross-sectional view of the embodiment. 1...metal plate, 2...adherent (molding), 3...
... Primer layer, 4 ... Adhesive layer, 5 ... Adherent (tape).

Claims (1)

[Scope of Claims] 1. A method in which a polyolefin molded article is used as an adherend and is adhered to another adherend using an adhesive, wherein the adhesive includes a polyurethane having a hydroxyl group at the end and a polyacrylic. An acrylic polyurethane adhesive consisting of at least one acrylic polymer selected from acids, derivatives thereof, polymethacrylic acid or derivatives thereof, and rubber as a primer on the side of the polyolefin molded body, and polyisocyanate and/or halogenated An adhesion method characterized by using a mixture with an agent. 2. The bonding method according to claim 1, wherein the other adherend is a polyvinyl chloride molded body. 3. The bonding method according to claim 1, wherein the polyisocyanate is mixed in a proportion of 0.1 to 50 parts by weight based on 100 parts by weight of rubber. 4 The halogenating agent is 0.002 parts by weight per 100 parts by weight of rubber.
The bonding method according to claim 1, wherein the adhesive is mixed in a proportion of 20 parts by weight. 5. The adhesive method according to claim 1, wherein the acrylic polyurethane adhesive is obtained by polymerizing an acrylic monomer in the presence of a polyurethane having a hydroxyl group at the end. 6. The bonding method according to claim 1, wherein the acrylic polyurethane contains an acrylic polymer component in a ratio of 10 to 500 parts by weight per 100 parts by weight of polyurethane. 7. The bonding method according to claim 1, wherein the polyolefin molded body is a tape that is bonded to the back side of a protection molding of an automobile.