JP5097373B2 - Polyol composition for polyolefin adhesive and use thereof - Google Patents

Description

  The present invention relates to a polyol composition for polyolefin adhesives, and an adhesive for polyolefins, a sealing material for polyolefins and a coating material for polyolefins using the polyol composition.

Polyolefin-based materials are used in various fields including the automobile field, the home appliance field, the packaging field, and the building material field. Since polyolefin resins, which are the main components of polyolefin materials, cannot be bonded with general adhesives, development of special adhesives for polyolefin resins has been actively studied. However, an adhesive having sufficient adhesion performance has not yet been obtained, and when a polyolefin-based material is adhered, the adhesion performance is improved by treating the surface with a primer or an electron beam.
On the other hand, many studies have been made on adhesives for polyolefins using hydroxyl-terminated polybutadienes having mainly 1,2 bond units, hydroxyl-terminated polybutadienes having mainly 1,4 bond units, and hydrogenated products thereof. However, few adhesives use a mixture of these hydroxyl-terminated polybutadienes.
For example, in Patent Document 1, a hydrogenated polybutadiene glycol that is polymerized mainly at 1,4 bonds at room temperature and a solid polybutadiene glycol that is polymerized mainly at 1,2 bonds is used in combination with a hydrogenated polybutadiene glycol that is liquid at room temperature. A curing agent composition having improved low-temperature stability is disclosed. However, the hydrogenated material that is solid at room temperature has a weak cohesive force after curing, and has low wettability at the bonding interface, so that sufficient adhesive strength cannot be obtained. Moreover, although the creep characteristic of adhesion | attachment is shown in the Example of patent document 1, in order to improve a low temperature characteristic, there exists a tendency for a creep characteristic to fall by adding the liquid hydrogenated material at the said normal temperature. It is shown.
Patent Documents 2 to 6 disclose compounds containing 1,2 bond units and 1,4 bond units in various proportions as polyolefin adhesives or vulcanized rubber adhesives. However, in any of Patent Documents 2 to 6, the ratio of 1,2 bond units to 1,4 bond units is the ratio of bond units randomly included in one polymer chain, It is not a mixture of a diene polymer having and a diene polymer having 1,4 bond units, and no such mixture is shown in these examples. In addition, compounds other than the diene polymer such as thermoplastic polyurethane and chloroprene rubber are used as essential components. Furthermore, the hydrogenated compounds used in Patent Documents 2 to 6 are all solid at room temperature. In this respect, the present invention is different from the techniques disclosed in Patent Documents 2 to 6.

Japanese Patent Laid-Open No. 06-158015 JP 54-127828 A JP 58-196227 A Japanese Patent Laid-Open No. 03-170580 Japanese Patent Laid-Open No. 03-247684 Japanese Patent Laid-Open No. 01-108286

  This invention is made | formed in view of the said situation, and it aims at providing the use of the novel polyol composition which gives the adhesive agent with favorable adhesiveness with polyolefin resin, and this polyol composition.

As a result of intensive studies, the present inventors have found that the above object can be achieved by a polyol composition containing a combination of specific liquid conjugated diene polymers. The present invention has been completed based on such findings.
That is, the present invention provides the following polyol composition for polyolefin adhesives, and polyolefin adhesives, polyolefin sealing materials and polyolefin coatings using the polyol composition.
1. (A) Hydroxyl-terminated conjugated diene polymer having 1,2 bond units in the molecule at 50 mol% or more at room temperature, and (B) hydroxyl group in liquid at room temperature having 1,4 bond units in excess of 50 mol% in the molecule. A polyol composition for polyolefin adhesives, comprising a combination comprising a terminal conjugated diene polymer.
2. 2. The polyol composition for polyolefin adhesive according to 1 above, wherein at least one of the hydroxyl group-terminated conjugated diene polymer of the component (A) and the component (B) is a hydrogenated liquid polyol at room temperature.
3. The polyol composition for polyolefin adhesives according to 1 or 2 above, wherein at least one of the hydroxyl group-terminated conjugated diene polymer of the component (A) and the component (B) is a hydroxyl group-terminated polybutadiene or a hydroxyl group-terminated polyisoprene.
4). The adhesive for polyolefins containing the polyol composition in any one of said 1-3, and a polyisocyanate type hardening | curing agent.
5. The sealing material for polyolefins containing the polyol composition in any one of said 1-3, and a polyisocyanate type hardening | curing agent.
6). 4. A polyolefin coating comprising the polyol composition according to any one of 1 to 3 above and a polyisocyanate curing agent.

  According to the present invention, it is possible to obtain a polyol composition for polyolefin adhesive that can remarkably improve the adhesion to a polyolefin resin, and an adhesive comprising a combination of this polyol composition and a polyisocyanate curing agent, Sealants, paints, adhesives, etc. are excellent in adhesion to polyolefin resins.

The polyol composition for polyolefin adhesives of the present invention (hereinafter sometimes simply referred to as “polyol composition”) is a (A) hydroxyl group that is liquid at room temperature and has 1,2 bond units of 50 mol% or more in the molecule. A terminal conjugated diene polymer (hereinafter sometimes abbreviated as “1,2-THPCD”) and (B) a hydroxyl-terminated conjugated diene polymer which is liquid at room temperature and has more than 50 mol% of 1,4 bond units in the molecule. (Hereinafter abbreviated as “1,4-THPCD”). Here, normal temperature refers to about 25 ° C.
In the polyol composition of the present invention, 1,2-THPCD and 1,4-THPCD are required to be liquid at room temperature. If one or both of these are solid at room temperature, the adhesive strength of the adhesive containing the polyol composition of the present invention as a blending component is significantly reduced.

In the 1,2-THPCD of the component (A), the content ratio of 1,2-bond units in the molecule is 50 mol% or more, but from the viewpoint of rubber elasticity and adhesive strength, preferably 55-95 mol%, Most preferably, it is 55-75 mol%.
In addition, in the 1,4-THPCD of the component (B), the content ratio of 1,4 bond units in the molecule is 50 mol% or more, but the adhesion with polyolefin resin and the room temperature liquidity of the hydrogenated compound are low. From the viewpoint, it is preferably 60 to 95 mol%, particularly preferably 70 to 90 mol%.

  In the polyol composition of the present invention, the mixing ratio of 1,2-THPCD and 1,4-THPCD is usually about 99: 1 to 1:99, preferably 90:10 to 10:90, particularly preferably, by mass ratio. Is 80: 20-20: 80. The appropriate mixing ratio varies depending on the type of adherend, but if the ratio of 1,2-THPCD and 1,4-THPCD is appropriate, 1,2 in the cured product of the polyol composition of the present invention, Since the ratio of the block structural units of -THPCD and 1,4-THPCD becomes appropriate, sufficient adhesiveness can be obtained.

In the polyol composition of the present invention, a hydrogenated compound obtained by hydrogenating one or both of 1,2-THPCD and 1,4-THPCD can be used. Since hydrogenated compounds have higher olefinic properties than non-hydrogenated compounds, the use of hydrogenated compounds improves wettability with polyolefin resins and provides excellent adhesion. In particular, a hydrogenated compound of a hydroxyl-terminated polyisoprene is preferable because it has low crystallinity and easily becomes liquid at room temperature. Furthermore, the hydrogenated compound is excellent in heat resistance, weather resistance, electrical properties and the like. On the other hand, the production of a hydrogenated compound requires a hydrogenation reaction at a high pressure, and the production method is complicated and expensive. Therefore, it is preferable to use an unhydrogenated compound from the viewpoint of economy.
In the polyol composition of the present invention, at least one of 1,2-THPCD and 1,4-THPCD is preferably hydroxyl-terminated polybutadiene or hydroxyl-terminated polyisoprene, and particularly preferably hydroxyl-terminated polybutadiene. Also, a butadiene-polyisoprene copolymer or a mixture of hydroxyl-terminated conjugated diene polymers can be used. In the case of a hydrogenated compound, polyisoprene is preferable because it has low crystallinity and easily becomes liquid at room temperature.

  In the polyol composition of the present invention, other than 1,2-THPCD and 1,4-THPCD for the purpose of improving physical properties, lowering viscosity, reducing costs and other purposes within the range not impairing the effects of the present invention. The polyol can be blended. Although there is no restriction | limiting in particular as another polyol, It is preferable that compatibility with 1, 2- THPCD and 1, 4-THPCD is favorable. Examples of other polyols that can be used include polyester polyols and polyether polyols. In the polyol composition of the present invention, the content of the other polyol is usually 20% by mass or less, preferably 10% by mass or less, based on the polyol composition. If the content of other polyols is large, the water resistance, moisture resistance, electrical properties and the like may be deteriorated. Further, 1,2-THPCD and 1,4-TFPCD of the present invention may contain other copolymerizable monomer units such as styrene, ethylene, propylene and the like within a range not impairing the characteristics.

As the hydroxyl-terminated conjugated diene polymer which is liquid at room temperature used in the present invention, commercially available hydroxyl-terminated conjugated diene polymers or those produced by a known method can be used. In order to produce this hydroxyl-terminated conjugated diene polymer, for example, one or more selected from diene monomers having 4 to 22 carbon atoms (butadiene, isoprene, chloroprene, 1,3-pentadiene, cyclopentadiene, etc.) are peroxidized. Hydrogen, an azo compound having a hydroxyl group (for example, 2,2′-azobis [2-methyl-N- (2-hydroxylethyl) propionamide, etc.) or a peroxide having a hydroxyl group (for example, cyclohexanone peroxide) is used as a polymerization initiator. A method of radical polymerization can be employed.
The polymerization initiator is used in an amount of about 1.0 to 50 parts by mass of hydrogen peroxide per 100 parts by mass of the diene monomer, 2,2′-azobis [2-methyl-N- (2-hydroxylethyl). Propionamide] is about 5.0 to 100 parts by mass, and cyclohexanone peroxide is about 5.0 to 100 parts by mass.
Although the above polymerization can be carried out without a solvent, it is preferably carried out in a solvent from the viewpoint of easy control of the reaction. As the solvent, ethanol, isopropanol, n-butanol and the like are usually used. The reaction temperature is suitably about 80 to 150 ° C., and the reaction time is suitably about 0.5 to 15 hours.

The hydroxyl-terminated conjugated diene polymer that is liquid at room temperature used in the present invention is prepared by anionic polymerization of the same diene monomer as described above using a catalyst such as naphthalene dilithium, and further reacting with a monoepoxy compound or the like. Can also be obtained. Although the polymerization can be carried out without a solvent, it is preferably carried out in a solvent from the same viewpoint as in the case of radical polymerization. As the solvent, saturated hydrocarbons such as hexane and cyclohexane are used. The reaction temperature is suitably about 50 to 100 ° C., and the reaction time is suitably about 1 to 10 hours. Moreover, in polymerization, two or more kinds of diene monomers may be mixed and used, and an addition polymerizable monomer having 2 to 22 carbon atoms may be added at a ratio of 50 mol% or less based on the diene monomer. .
Examples of the addition polymerizable monomer having 2 to 22 carbon atoms include butene, pentene, styrene, α-methylstyrene, acrylonitrile, acrylic acid and its ester, methacrylic acid and its ester, vinyl chloride, vinyl acetate, acrylamide and the like. .
After completion of the reaction, the solvent is distilled under reduced pressure to remove the solvent, unreacted monomers, and the like, thereby obtaining a hydroxyl group-terminated conjugated diene polymer.

In general, when the former radical polymerization method is used, a compound mainly containing 1,4 bond units is obtained. On the other hand, when the latter anion polymerization method is used, a compound mainly containing 1,2 bond units is obtained. .
The number average molecular weight of the hydroxyl-terminated conjugated diene polymer used in the polyol composition of the present invention is usually about 300 to 10,000, preferably 500 to 5,000, and the hydroxyl group content is usually about 0.2 to 10 meq / g, preferably 0.5 to 5 meq / g, particularly preferably 0.7 to 2 meq / g. The hydroxyl group can be contained inside the molecular chain in addition to the molecular end.

The present invention also provides a polyolefin adhesive, a polyolefin sealing material, and a polyolefin coating comprising the polyol composition and a polyisocyanate curing agent. The polyolefin adhesive, polyolefin sealing material and polyolefin coating of the present invention are liquid polymer compositions.
The polyisocyanate compound used as the curing agent is not particularly limited, but is selected in consideration of reactivity, safety, cost, physical properties of the obtained cured product, and the like. As the polyisocyanate compound, a prepolymer synthesized by separately reacting polyol and polyisocyanate can also be used.
The polyisocyanate compound is an organic compound having two or more isocyanate groups in one molecule, and has a reactive isocyanate group that reacts with the hydroxyl group of the liquid hydroxyl-terminated conjugated diene polymer or its hydrogenated compound. is there. Examples of the polyisocyanate compound include ordinary aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.

  Specifically, for example, 4,4′-diphenylmethane diisocyanate, 2,2′-diphenylmethane diisocyanate, a mixture of 4,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate (all MDI), tolylene diisocyanate (TDI) ), Carbodiimide-modified diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, phenylene diisocyanate, naphthalene-1,5-diisocyanate, o-toluidine diisocyanate, triphenylmethane triisocyanate, tris (isocyanatophenyl) thiophosphate and isopropylbenzene-2,4- Aromatic polyisocyanates such as diisocyanate can be mentioned.

Also, aliphatic-aromatic polyisocyanates such as xylylene diisocyanate (XDI) and tetramethylxylylene diisocyanate (TMXDI) And a polyisocyanate bonded to).
Further, hexamethylene diisocyanate, dodecane diisocyanate, lysine diisocyanate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate, Mention may be made of aliphatic polyisocyanates such as trimethylhexamethylene diisocyanate.
Furthermore, transcyclohexane-1,4-diisocyanate, bicycloheptane triisocyanate, isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tetramethylxylylene diene Mention may be made of alicyclic polyisocyanates such as isocyanate.

In addition, cyclized trimers (isocyanurate-modified products), burette-modified products, ethylene glycol, 1,4-butanediol, propylene glycol, dipropylene glycol, trimethylolpropane, polyether polyol, polymer Polyol compounds such as polyols, polytetramethylene ether glycol, polyester polyols, acrylic polyols, polyalkadiene polyols, hydrides of polyalkadiene polyols, partially saponified ethylene-vinyl acetate copolymers, castor oil-based polyols, and the above polyisocyanate compounds And an addition reaction product.
These polyisocyanate compounds can also be used as a mixture of two or more. Further, the isocyanate groups of these polyisocyanate compounds are converted into phenols, oximes, imides, mercaptans, alcohols, ε-caprolactam, ethyleneimine. Also, so-called blocked isocyanate compounds blocked with a blocking agent such as α-pyrrolidone, diethyl malonate, sodium hydrogen sulfite, and boric acid can be used.
The amount of polyisocyanate used is usually an amount such that NCO / OH (molar ratio) is 0.5 to 2.5, and preferably 0.8 to 1.5.

The liquid polymer composition which is an adhesive for polyolefin, a sealing material for polyolefin or a coating for polyolefin of the present invention has improved adhesion, other physical properties, improved processability due to reduced viscosity, heat resistance, weather resistance and chemical resistance. In order to improve the above, known additives can be added. Examples of such additives include inorganic fillers, organic fillers, antioxidants, ultraviolet anti-aging agents, antistatic agents and other stabilizers, extenders for reducing costs, colorants such as pigments and dyes, Examples include plasticizers, process oils, and bitumen substances.
By adding an inorganic filler to the liquid polymer composition, the adhesion to the polyolefin resin is significantly improved. Inorganic fillers include zinc, aluminum, copper, nickel, glass sphere, glass flake, glass fiber, carbon black (channel black, furnace black, acetylene black, thermal black), carbon fiber, graphite, asbestos, kaolin clay, wax Stone clay, talc, gypsum, cryolite, wollastonite, diatomaceous earth, slate powder, whiting, feldspar powder, mica, gypsum, quartz powder, fine silica, attapulgite, sericite, volcanic ash, meteorite, silica, alumina , Zinc oxide, magnesium oxide, zirconium oxide, titanium oxide, iron oxide, molybdenum dioxide, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, barium sulfate, calcium silicate, zeolite, potassium titanate, nitriding C iodine, may be mentioned boron nitrite and molybdenum disulfide. As the inorganic filler, calcium carbonate is particularly preferable.

Organic fillers include rubber powder, cellulose, lignin, chitin, leather powder, coconut shell, wood powder, cotton, hemp, wool, silk, and other natural fibers, nylon, polyester, vinylon, acetate, acrylic, etc. Synthetic resins such as synthetic fiber, polyethylene resin, polypropylene resin, polystyrene resin, acrylonitrile-butadiene-styrene resin, polycarbonate resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polymethyl methacrylate resin, polyvinyl chloride resin, epoxy resin, phenol resin The powder or granule of this can be mentioned.
Although there is no restriction | limiting in particular about the compounding quantity of these inorganic fillers and organic fillers, Usually, it is 500 mass parts or less with respect to 100 mass parts of polyol compositions of this invention, Preferably it is 200 mass parts or less.

The liquid polymer composition containing the polyol composition and the polyisocyanate curing agent is prepared by blending the above components in the above proportions. In preparing this liquid polymer composition, using a mixing device, a kneading device or the like, usually at a temperature of about 0 to 120 ° C, preferably at a temperature of 15 to 100 ° C, about 0.5 seconds to 8 hours, preferably 1 second to Stir and mix for 5 hours. For the preparation of the liquid polymer, a method called a one-shot method or a method called a prepolymer method is usually used.
In the one-shot method, first, at least the components other than the polyisocyanate compound are blended and mixed at the above temperature and time to obtain a mixture. A polyisocyanate compound and additive components not used in the previous mixing are added to this mixture and mixed at the above temperature and time to obtain a liquid polymer composition. The preferred NCO / OH (molar ratio) in this liquid polymer composition is 0.5 to 2.5.

The prepolymer method includes the following prepolymer method (1) and prepolymer method (2). In the prepolymer method (1), NCO / OH, NCO / NH ₂ or NCO / (OH + NH ₂ ) is in the range of 1.7 to 25 (equivalent ratio), preferably 1.7 to 5.5. At least one of a diene polymer and a polyamine compound is reacted with a polyisocyanate compound to obtain a prepolymer. This reaction may be performed in the presence of a part or all of the other compounding components, or may be performed in the absence of the other compounding components. Similarly to the above, the reaction temperature is usually about 0 to 120 ° C., preferably 15 to 100 ° C., and the reaction time is usually about 0.1 to 10 hours, preferably 0.5 to 8 hours. The remaining blending components are mixed with this prepolymer at the same temperature and reaction time as described above to obtain a liquid polymer composition.

Prepolymer method in (2), NCO / OH, NCO / NH 2 or in the range of NCO / (OH + NH2) is 1.7 to 5.0 (equivalent ratio) was blended blending all components, it reacted with the prepolymer Get. The reaction temperature is the same as in the prepolymer method (1), and the time is usually 0.1 to 10 hours, preferably 0.5 to 8 hours. By reacting this prepolymer with moisture (water) in the air, a liquid polymer composition is obtained.
The liquid polymer composition thus prepared is used for various applications including adhesives for polyolefins, sealing materials for olefins, and coatings for olefins. give.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
Example 1
Hydroxyl-terminated polybutadiene polyol (manufactured by Idemitsu Kosan Co., Ltd., Poly bd R-45HT; containing 1,4 bonds 80 mol%, liquid) and hydroxyl-terminated polybutadiene polyol (US Sartomer, KRASOL-LBH-P2000; 1, 2 The mixture was mixed at a mass ratio of 75:25. Diphenylmethane diisocyanate (125M, manufactured by Nippon Polyurethane Industry Co., Ltd.) as a polyisocyanate curing agent was added to this so as to be 1.05 in NCO / OH (molar ratio), and then mixed as a reaction catalyst. Dibutyltin dilaurate (manufactured by Kyodo Yakuhin Co., Ltd.) was added at a mass ratio of 0.01 to prepare a liquid adhesive composition.
As an adherent, the adhesive composition was applied to two PP plates (manufactured by Prime Polymer Co., Ltd., J-6083HP) having a thickness of 3 mm, a width of 25 mm, and a length of 100 mm, the surfaces of which were wiped with isopropyl alcohol, Superimposed. In this state, after curing for 72 hours in an environment of a temperature of 25 ° C. and a humidity of 60%, tensile shear bond strength (with Tensilon manufactured by A & D Co., Ltd.) According to JIS K6848: 1999 and JIS K6850: 1999), it was 0.57 MPa.

Example 2
In Example 1, instead of hydroxyl-terminated polybutadiene polyol (made by Idemitsu Kosan Co., Ltd., Poly bd R-45HT; 1,4 bond content 80 mol%, liquid), hydrogenated polyisoprene polyol (made by Idemitsu Kosan Co., Ltd.) EPOL; 1,4 bond content 80 mol%, liquid), and mass ratio of this EPOL and hydroxyl-terminated polybutadiene polyol (US Sartomer, KRASOL-LBH-P2000; 1,2 bond content 65 mol%, liquid) An adhesive composition was prepared in the same manner as in Example 1 except that the composition was used at 50:50. The tensile shear adhesive strength was measured by the same method as in Example 1, and it was 0.71 MPa.

Example 3
In Example 2, EPOL and KRASOL-HLBH were used in place of KRASOL-LBH-P2000 using hydroxyl-terminated hydrogenated polybutadiene polyol (US Sartomer, KRASOL-HLBH-P2000; 1,2 bond content 65 mol%, liquid). An adhesive composition was prepared in the same manner as in Example 2 except that -P2000 was used at a mass ratio of 25:75. The tensile shear adhesive strength was measured by the same method as in Example 1, and it was 0.77 MPa.

Example 4
Example 1 Example 1 except that 100 parts by mass of calcium carbonate (Shiraishi Kogyo Co., Ltd., White Glossy CCR) is added to 100 parts by mass of the total amount of Poly bd R-45HT and KRASOL-LBH-P2000 in Example 1. 1 was used to prepare an adhesive composition. The tensile shear bond strength was measured by the same method as in Example 1, and it was 1.00 MPa.

Comparative Examples 1 and 2
In Example 1, the adhesive composition was prepared in the same manner as in Example 1 except that only one of Poly bd R-45HT and KRASOL LBH-P2000 was used and the NCO / OH (molar ratio) was 1.05. Produced. When trying to measure the tensile shear adhesive strength by the same method as in Example 1, the test piece was peeled off before measurement or at the start of measurement in any case.

Comparative Example 3
In Example 3, adhesion was performed in the same manner as in Example 3 except that hydrogenated polybutadiene polyol (manufactured by Mitsubishi Chemical Corporation, polytail H; 1,4 bond content 80 mol%, solid) was used instead of EPOL. An agent composition was prepared. The tensile shear bond strength was measured by the same method as in Example 1 and found to be 0.29.
The above examples and comparative examples are summarized in the following table.

The polyol composition for polyolefin adhesive of the present invention and the liquid polymer composition containing an isocyanate curing agent are used for various applications including a polyolefin adhesive, a polyolefin sealing material, and a polyolefin coating, and cured. Various forms of cured products are obtained by processing.

Claims (3)

(A) and hydroxyl-terminated conjugated diene polymer is liquid at room temperature having a 1,2-bond units from 55 to 65 mol% in the molecule, it is liquid at room temperature with 60 to 95 mole% 1,4-bond units in (B) molecule The polyolefin adhesive agent which contains the polyol composition which mixed the hydroxyl group terminal conjugated diene polymer of this by the ratio of 80: 20-20: 80 by mass ratio, and a polyisocyanate type hardening | curing agent.   2. The polyolefin adhesive according to claim 1, wherein at least one of the hydroxyl group-terminated conjugated diene polymer of the component (A) and the component (B) is a hydrogenated liquid polyol at room temperature.   The polyolefin adhesive according to claim 1 or 2, wherein at least one of the hydroxyl group-terminated conjugated diene polymer of the component (A) and the component (B) is a hydroxyl group-terminated polybutadiene or a hydroxyl group-terminated polyisoprene.