JP2021109895A - Adhesive - Google Patents

Abstract

To provide an adhesive excellent in adhesiveness, followability and heating stability.SOLUTION: There is provided an adhesive containing an ethylene-1-butene copolymer (A) satisfying all of the following requirements (A-1) to (A-4): (A-1) the MFR measured at 190°C and under a load of 2.16 kg load is 0.1 to 50 g/10 min; (A-2) the density is 855 to 900 kg/m3; (A-3) the content of a structural unit derived from 1-butene is 6 to 25 mol%; and (A-4) the total content of a vinyl type double bond, a vinylidene type double bond, a 2-substituted olefin-type double bond and a 3-substituted olefin-type double bond per 1000 carbon atoms determined by 1H-NMR measurement is 0.5 or less.SELECTED DRAWING: None

Description

The present invention relates to adhesives, especially hot melt adhesives.

Adhesives are widely used in fields such as packaging, bookbinding, plywood, and woodworking. For example, the amount of hot melt adhesive used is increasing year by year because initial adhesion can be obtained in a short time by cooling and solidifying after application, workability is good, and it is solvent-free and has little impact on the environment. There is.

Conventionally, ethylene-vinyl acetate copolymer (EVA) has been used as a base polymer for hot melt adhesives. In recent years, lower density polymers such as ethylene / α-olefin copolymers have also been used for the purpose of improving heat resistance and reducing costs (see, for example, Patent Documents 1 and 2).

Special Table 2000-515190 Gazette Special Table No. 7-501845

Conventional adhesives containing an ethylene / α-olefin copolymer as a base polymer exhibit even higher adhesive strength due to the diversifying needs of recent years, for example, the adhesive joint is repeatedly curved or bent to deform. There was room for further improvement from the viewpoint of maintaining high adhesive strength (hereinafter, also referred to as "followability") even when the above was added. Further, such conventional adhesives, particularly hot melt type adhesives, may be discolored when treated at a high temperature for a long time during manufacturing or coating, which is further improved from the viewpoint of heating stability. There was room for.

An object of the present invention is to improve an adhesive containing an ethylene / α-olefin copolymer as a base polymer from the viewpoint of adhesiveness, particularly followability, and from the viewpoint of heat stability.

As a result of examining these points, the present inventor has as a base polymer, an ethylene / α-olefin copolymer having the following composition, that is, an ethylene / 1-butene copolymer having a relatively high molecular weight and a specific range of densities. By using an ethylene / 1-butene copolymer having a small amount of double bonds and having a small amount of double bonds, the above-mentioned problems can be solved, and an adhesive having excellent adhesiveness, particularly followability, and heating stability can be provided. We have found and completed the present invention.

The present invention relates to the following [1] to [7].
[1] An adhesive containing an ethylene / 1-butene copolymer (A) that satisfies all of the following requirements (A-1) to (A-4).
(A-1) The MFR measured at 190 ° C. and a load of 2.16 kg is 0.1 to 50 g / 10 minutes.
(A-2) The density is 855 to 900 kg / m ³ .
(A-3) The content of the structural unit derived from 1-butene is 6 to 25 mol%.
^{(A-4) 1 H-} NMR vinyl type double bond number per 1000 carbon which is determined by measurement, vinylidene-type double bonds, disubstituted olefinic double bonds and 3 the total content of substituted olefinic double bonds However, it is less than 0.5.

[2] Vinyl type double bond, vinylidene type double bond, 2-substituted olefin type double bond and 3-substituted olefin type per 1000 carbon atoms determined by ¹ H-NMR measurement of the copolymer (A). The adhesive according to the above [1], wherein the content of any double bond of the double bond is less than 0.2.

[3] The adhesive according to the above [1] or [2], wherein the MFR of the copolymer (A) measured at 190 ° C. and a load of 2.16 kg is 0.1 to 9 g / 10 minutes.
[4] The adhesive according to any one of [1] to [3] above, wherein the copolymer (A) has a density of 855 to 875 kg / m ^3.

[5] The adhesive according to any one of [1] to [4] above, wherein the content of the structural unit derived from 1-butene of the copolymer (A) is 15 to 25 mol%.
[6] The adhesive according to any one of [1] to [5] above, which comprises a tackifier and / or a wax.
[7] The adhesive according to any one of the above [1] to [6], which is a hot melt adhesive.

The adhesive of the present invention is excellent in adhesiveness, particularly followability, and thermal stability.

The adhesive of the present invention will be described with reference to preferred embodiments.
〔glue〕
The adhesive of the present invention contains an ethylene / 1-butene copolymer (A) that meets specific requirements.
The adhesive of the present invention can be used as a so-called hot melt adhesive capable of adhering various adherends in a state where it is solid at room temperature and is heated and melted at the time of use to impart fluidity.

<Ethylene 1-butene copolymer (A)>
The ethylene / 1-butene copolymer (A) (hereinafter, also referred to as “copolymer (A)”) satisfies all of the following requirements (A-1) to (A-4).

(A-1) The MFR measured at 190 ° C. and a load of 2.16 kg is 0.1 to 50 g / 10 minutes.
(A-2) The density is 855 to 900 kg / m ³ .
(A-3) The content of the structural unit derived from 1-butene is 6 to 25 mol%.
^{(A-4) 1 H-} NMR vinyl type double bond number per 1000 carbon which is determined by measurement, vinylidene-type double bonds, disubstituted olefinic double bonds and 3 the total content of substituted olefinic double bonds However, it is less than 0.5.

≪ (A-1) MFR (melt flow rate) ≫
The melt flow rate (MFR, ASTM D1238) of the copolymer (A) at 190 ° C. under a 2.16 kg load is 0.1 to 50 g / 10 min, preferably 0.1 to 9 g / 10 min. , More preferably 0.3 to 5 g / 10 minutes. When the MFR falls below the above range, the fluidity is lowered, and the adhesive containing the copolymer (A) is poorly handled and difficult to apply at high speed. When the MFR exceeds the above range, the adhesive containing the copolymer (A) deteriorates in oil resistance and creep resistance.

≪ (A-2) Density ≫
The copolymer (A) has a density of 855 to 900 kg / m ³ , preferably 855 to 890 kg / m ³ , more preferably 855 to 875 kg / m ³ , and particularly preferably 858 to 865 kg / m. It is ^3. The density of the copolymer (A) is a value measured by ASTM D1505 at 23 ° C. By using the copolymer (A) whose density and Mn are in the above ranges, the adhesiveness in a high temperature environment is excellent, and the melting treatment temperature at the time of coating is good even at a low temperature (eg, 130 to 150 ° C.). Since it has coatability, it is possible to obtain an adhesive that is advantageous from the viewpoint of energy saving. Further, by using the copolymer (A) whose density is in the above-mentioned preferable range, it is possible to obtain an adhesive having excellent adhesiveness in a low temperature environment (eg, -30 to 0 ° C.).

≪ (A-3) 1-butene content≫
The ethylene / 1-butene copolymer (A) is a copolymer having a structural unit derived from ethylene and a structural unit derived from 1-butene.

The 1-butenkomonomer has an appropriate degree of incorporation into polyethylene crystals, and the ethylene / 1-butene copolymer (A) is compared with a copolymer of ethylene and an olefin having 5 or more carbon atoms. There is an advantage that the crystallinity is not easily lowered and the mechanical strength is not easily impaired even if the copolymer content is increased in order to increase the compatibility with the tackifier. On the other hand, the ethylene / 1-butene copolymer (A) is superior in compatibility with the tackifier as compared with the copolymer of ethylene and propylene having 3 carbon atoms.

The content of the butene-derived structural unit in the copolymer (A) is usually 6 to 25 mol%, preferably 10 to 25 mol%, and more preferably 15 to 25 mol% in the total repeating structural unit. It is particularly preferably 18 to 23 mol%. If the structural unit derived from 1-butene is less than the above range, the crystallinity is high and sufficient surface followability as an adhesive cannot be obtained. In an ethylene / 1-butene copolymer in which the structural unit derived from 1-butene exceeds the above range, the crystallinity is excessively lowered, the stickiness is increased, and the mechanical strength is lowered.

To the extent that the object of the present invention is not impaired, the ethylene / 1-butene copolymer (A) contains propylene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3 Α-olefins such as −methyl-1-pentene, 1-octene, 1-decene, 1-dodecene and, if necessary, other conomomers such as 1,6-hexadiene, 1,8-octadene, norbornene and the like. Dienes and structural units derived from cyclic olefins such as styrene, cyclohexene and cyclopentene may be contained in a small amount.

When the copolymer (A) contains a structural unit derived from an α-olefin other than 1-butene, the type of the structural unit derived from the α-olefin in the copolymer (A) is, for example, a 10 mmφ sample tube. ^{The 13} C-NMR spectrum of the sample in which about 200 mg of the copolymer (A) was uniformly dissolved in 1 ml of hexachlorobutadiene was measured at a temperature of 120 ° C., a frequency of 25.05 MHz, a spectrum width of 1500 Hz, and a pulse repetition time of 4.2. It can be identified by measuring under the measurement conditions of 2 seconds and a 45 ° pulse width of 6 μs.

≪ (A-4) Double bond amount≫
The double bonds that can be contained in the ethylene / 1-butene copolymer (A) include the vinyl type double bond, the vinylidene type double bond, the disubstituted olefin type double bond, and the trisubstituted olefin described below. Type double bond can be mentioned.

In each equation, * indicates a bond with an atom other than a hydrogen atom.
The copolymer (A) is at least one double selected from a vinyl type double bond, a vinylidene type double bond, a disubstituted olefin type double bond and a trisubstituted olefin type double bond per 1000 carbon atoms. The content of the bonds is preferably less than 0.2, more preferably less than 0.1, and even more preferably 0 to 0.09.

The copolymer (A) has a total content of vinyl type double bond, vinylidene type double bond, disubstituted olefin type double bond and trisubstituted olefin type double bond per 1000 carbon atoms. The number is preferably less than 5, more preferably 0.4 or less, further preferably 0.3 or less, and particularly preferably less than 0.3.

The amount of double bond can be determined by ^{1 1 H-NMR.}
In the copolymer (A), if the amount of double bonds per 1000 carbon atoms exceeds the above range, a cross-linking reaction may occur at the time of applying an adhesive or the like, and charring may occur. On the other hand, when the amount of the double bond is within the above range, it is difficult to form a gel that causes charring even if the adhesive is treated at a high temperature (eg, about 180 ° C.) for a long time at the time of application or the like. Therefore, the adhesive containing the copolymer (A) can prevent discoloration even when it is treated at a high temperature for a long time in a processing machine nozzle, for example, and is excellent in heating stability.

<< Other physical properties of copolymer (A) >>
(1) Weight average molecular weight (Mw)
The copolymer (A) has a weight average molecular weight (Mw) of preferably 20,000 to 1,000,000, more preferably 50,000 to 500,000, and even more preferably 120,000 to 350,000. Is. Mw is a polystyrene-equivalent value measured by a gel permeation chromatography (GPC) method. The copolymer (A) having Mw in the above range has an excellent balance between mechanical strength and fluidity, and the adhesive containing the copolymer (A) can achieve both high adhesiveness and handleability.

(2) Molecular weight distribution (Mw / Mn)
The copolymer (A) has a molecular weight distribution (Mw / Mn) of preferably 3.5 or less, more preferably 3.0 or less. Mw / Mn is a polystyrene-equivalent value measured by the GPC method. The copolymer (A) having Mw / Mn in the above range is preferable because it has few low molecular weight components that lower the mechanical strength.

<Method for producing ethylene / 1-butene copolymer (A)>
The ethylene / 1-butene copolymer (A) has the above-mentioned properties, and the production method thereof is not limited in any way. For example, the copolymer (A) can be produced by copolymerizing ethylene and 1-butene in the presence of a catalyst for olefin polymerization containing the catalyst components [A] and [B].

<Catalyst component [A]>
The catalyst component [A] is a metallocene compound represented by the general formula [I].

In formula [I], M is a transition metal, p represents the valence of the transition metal, X may be the same or different, and each is an independent hydrogen atom, halogen atom or hydrocarbon group, R. ¹ and R ² are π-electron conjugated ligands that are independently coordinated to M, respectively.

Examples of the transition metal represented by M include Zr, Ti, Hf, V, Nb, Ta and Cr, the preferred transition metal is Zr, Ti or Hf, and the more preferred transition metal is Zr or Hf. be.

Examples of the π-electron conjugated ligand represented by R ¹ and R ² include an η-cyclopentadienyl structure, a η-benzene structure, a η-cycloheptatrienyl structure, and a η-cyclooctatetraene structure. Ligands are mentioned, and a particularly preferable ligand is a ligand having an η-cyclopentadienyl structure. Examples of the ligand having the η-cyclopentadienyl structure include a cyclopentadienyl group, an indenyl group, a hydrogenated indenyl group, and a fluorenyl group. These groups are further substituted with halogen atoms; hydrocarbon groups such as alkyl, aryl and aralkyl; oxygen atom-containing groups such as alkoxy groups and aryloxy groups; and hydrocarbon group-containing silyl groups such as trialkylsilyl groups. You may.

Examples of the catalyst component [A] include, but are not limited to, bis (1,3-dimethylcyclopentadienyl) zirconium dichloride. Such a catalyst component [A] is preferably used as a catalyst for olefin polymerization together with the catalyst component [B].

<Catalyst component [B]>
The catalyst component [B] is selected from (b-1) an organoaluminum oxy compound, (b-2) a compound that reacts with the catalyst component [A] to form an ion pair, and (b-3) an organoaluminum compound. At least one compound.

The catalyst component [B] is prepared from the viewpoint of the polymerization activity and the properties of the produced olefin polymer.
[1] Only organoaluminum oxy compound (b-1),
[2] Organoaluminium oxy compound (b-1) and organoaluminum compound (b-3),
[3] The compound (b-2) and the organoaluminum compound (b-3),
[4] Organoaluminium oxy compound (b-1) and the compound (b-2),
It is preferably used in any of the above embodiments.

≪Organoaluminium oxy compound (b-1) ≫
As the organoaluminum oxy compound (b-1), conventionally known aluminoxane can be used as it is. Specific examples thereof include compounds represented by the general formula [II] and / or the general formula [III].

In formulas [II] and [III], R is a hydrocarbon group having 1 to 10 carbon atoms, and n is an integer of 2 or more. In particular, a methylaluminoxane in which R is a methyl group and n of 3 or more, preferably 10 or more is preferably used. The organoaluminum oxy compound in which R is a methyl group in the formula [II] or [III] may be hereinafter referred to as "methylaluminoxane".

As the organoaluminum oxy compound (b-1), it is also preferable to use a methylaluminoxane analog that dissolves in saturated hydrocarbons, and for example, modified methylaluminoxane as represented by the general formula [IV] can be exemplified. ..

In the formula [IV], R is a hydrocarbon group having 2 to 20 carbon atoms, and m and n are integers of 2 or more.
The modified methylaluminoxane represented by the formula [IV] is prepared by using, for example, trimethylaluminum and alkylaluminum other than trimethylaluminum, and is prepared by a manufacturer such as Toso Finechem Co., Ltd. using trimethylaluminum and triisobutylaluminum. Those in which R is an isobutyl group are commercially produced under trade names such as MMAO and TMAO.

As the organoaluminum oxy compound (b-1), a benzene-insoluble organoaluminum oxy compound exemplified in JP-A-2-78687 may be used, and contains boron represented by the general formula [V]. Organoaluminium oxy compounds may be used.

In formula [V], R ^c is a hydrocarbon group having 1 to 10 carbon atoms, and R ^d may be the same or different from each other, and is a hydrogen atom, a halogen atom or a hydrocarbon having 1 to 10 carbon atoms. It is a group.

The organoaluminum oxy compound (b-1) may be used alone or in combination of two or more. It should be noted that the organoaluminum oxy compound (b-1) may contain a small amount of the organoaluminum compound.

<< Compound (b-2) that reacts with the catalyst component [A] to form an ion pair >>
As the compound (b-2) that reacts with the catalyst component [A] to form an ion pair (hereinafter, may be abbreviated as “ionic compound (b-2)”), Special Table No. 1-501950. Japanese Patent Application Laid-Open No. 1-502036, Japanese Patent Application Laid-Open No. 3-179005, Japanese Patent Application Laid-Open No. 3-179006, Japanese Patent Application Laid-Open No. 3-207703, Japanese Patent Application Laid-Open No. 3-207704, US Pat. No. 5,321106 Examples thereof include Lewis acid, an ionic compound, a borane compound and a carborane compound described in the above. Further, examples of the ionic compound (b-2) include heteropoly compounds and isopoly compounds.
The ionic compound (b-2) is preferably a compound represented by the general formula [VI].

Wherein [VI], as R e ⁺ is, for example, H ^+, carbenium cation, oxonium cation, ammonium cation, phosphonium cation, cycloheptyltrienyl cation, and a ferrocenium cation having a transition metal. R ^{f to} R ⁱ may be the same or different from each other, and are organic groups, preferably aryl groups.

Specific examples of the carbocation cation include a trisubstituted carbocation cation such as a triphenyl carbocation cation, a tris (methylphenyl) carbocation cation, and a tris (dimethylphenyl) carbocation cation.

Specific examples of the ammonium cation include trialkylammonary cations such as trimethylammonium cation, triethylammonary cation, tri (n-propyl) ammonium cation, triisopropylammonium cation, tri (n-butyl) ammonium cation, and triisobutylammonium cation. N, N-dialkylanilinium cations such as N, N-dimethylanilinium cations, N, N-diethylanilinium cations, N, N-2,4,6-pentamethylanilinium cations, diisopropylammonium cations, dicyclohexylammonium Examples thereof include dialkylammonium cations such as cations.

Specific examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tris (methylphenyl) phosphonium cation, and tris (dimethylphenyl) phosphonium cation.

^{Among the above, as Re +} , a carbonium cation and an ammonium cation are preferable, and a triphenylcarbenium cation, an N, N-dimethylanilinium cation, and an N, N-diethylanilinium cation are particularly preferable.

Specifically, as the ionic compound (b-2) which is a carbenium salt, triphenylcarbenium tetraphenylborate, triphenylcarbenium tetrakis (pentafluorophenyl) borate, triphenylcarbenium tetrakis (3,5-ditrifluoro) Examples thereof include methylphenyl) borate, tris (4-methylphenyl) carbenium tetrakis (pentafluorophenyl) borate, and tris (3,5-dimethylphenyl) carbenium tetrakis (pentafluorophenyl) borate.

Specific examples of the ionic compound (b-2) which is an ammonium salt include a trialkyl-substituted ammonium salt, an N, N-dialkylanilinium salt, and a dialkylammonium salt.

Specifically, as the ionic compound (b-2) which is a trialkyl-substituted ammonium salt, triethylammonium tetraphenylborate, tripropylammonium tetraphenylborate, tri (n-butyl) ammonium tetraphenylborate, trimethylammonium tetrakis (p). -Trill) Borate, trimethylammonium tetrakis (o-tolyl) borate, tri (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, triethylammonium tetrakis (pentafluorophenyl) borate, tripropylammonium tetrakis (pentafluorophenyl) borate , Tripropylammonium tetrakis (2,4-dimethylphenyl) borate, tri (n-butyl) ammonium tetrakis (3,5-dimethylphenyl) borate, tri (n-butyl) ammonium tetrakis (4-trifluoromethylphenyl) borate , Tri (n-butyl) ammonium tetrakis (3,5-ditrifluoromethylphenyl) borate, tri (n-butyl) ammonium tetrakis (o-tolyl) borate, dioctadecylmethylammonium tetraphenylborate, dioctadecylmethylammonium tetrakis ( p-tolyl) borate, dioctadecylmethylammonium tetrakis (o-tolyl) borate, dioctadecylmethylammonium tetrakis (pentafluorophenyl) borate, dioctadecylmethylammonium tetrakis (2,4-dimethylphenyl) borate, dioctadecylmethylammonium tetrakis Examples thereof include (3,5-dimethylphenyl) borate, dioctadecylmethylammonium tetrakis (4-trifluoromethylphenyl) borate, dioctadecylmethylammonium tetrakis (3,5-ditrifluoromethylphenyl) borate, and dioctadecylmethylammonium.

Specifically, as the ionic compound (b-2) which is an N, N-dialkylanilinium salt, N, N-dimethylanilinium tetraphenylborate, N, N-dimethylanilinium tetraphenyl (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (3,5-ditrifluoromethylphenyl) borate, N, N-diethylanilinium tetraphenylborate, N, N-diethylanilinium tetrakis (pentafluorophenyl) borate, N, N- Diethylanilinium tetrakis (3,5-ditrifluoromethylphenyl) borate, N, N, 2,4,6-pentamethylanilinium tetraphenylborate, N, N, 2,4,6-pentamethylanilinium tetrakis ( Pentafluorophenyl) borate can be mentioned.

Specific examples of the dialkylammonium salt include di (1-propyl) ammonium tetrakis (pentafluorophenyl) borate and dicyclohexylammonium tetraphenylborate.

As the other ionic compound (b-2), the ionic compound disclosed by the present applicant (Japanese Unexamined Patent Publication No. 2004-51676) can also be used without limitation.
The ionic compound (b-2) may be used alone or in combination of two or more.

≪Organoaluminium compound (b-3) ≫
Examples of the organoaluminum compound (b-3) include organoaluminum compounds represented by the general formula [VII] and complex alkylated products of a Group 1 metal of the periodic table represented by the general formula [VIII] and aluminum. Be done.

_{^{R a m Al (OR b)}} n H p X q ... [VII]
In formula [VII], ^Ra and R ^b may be the same or different from each other and are hydrocarbon groups having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, where X is a halogen atom and m is. 0 <m ≦ 3, n is 0 ≦ n <3, p is 0 ≦ p <3, q is a number of 0 ≦ q <3, and m + n + p + q = 3.

Specific examples of the organic aluminum compound represented by the formula [VII] include tri-n-alkylaluminum such as trimethylaluminum, triethylaluminum, tri-n-butylaluminum, trihexylaluminum, and trioctylaluminum; triisopropylaluminum, Tri-branched alkylaluminum such as triisobutylaluminum, tri-sec-butylaluminum, tri-tert-butylaluminum, tri-2-methylbutylaluminum, tri-3-methylhexylaluminum, tri-2-ethylhexylaluminum; tricyclohexyl aluminum, tri-cycloalkyl aluminum such as tri-cyclooctyl aluminum; triphenyl aluminum, triaryl aluminum such as tri-tolyl aluminum, diisopropyl aluminum hydride, dialkylaluminum hydride such as diisobutylaluminum hydride; formula _{(i-C 4 H 9)} xAly (C ₅ H ₁₀ ) _z (In the formula, x, y, z are positive numbers and z ≦ 2x) and the like, alkenyl aluminum such as isoprenyl aluminum; isobutylaluminum methoxyde, isobutylaluminum. Alkylaluminum alkoxides such as ethoxydo; Dialkylaluminum alkoxides such as dimethylaluminum methoxyd, diethylaluminum ethoxide and dibutylaluminum butoxide; Alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxydo and butylaluminum sesquibutoxide; General formula ^Ra _2.5 Al (OR ^b ) _{Partially alkoxylated alkylaluminum with an average composition represented by 0.5} mag; alkylaluminum such as diethylaluminum phenoxide, diethylaluminum (2,6-di-t-butyl-4-methylphenoxide). Allyloxide; dialkylaluminum halides such as dimethylaluminum chloride, diethylaluminum chloride, dibutylaluminum chloride, diethylaluminum bromide, diisobutylaluminum chloride; alkylaluminum sesquihalides such as ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum sesquibramide; Partially halo such as alkylaluminum dihalide such as ethylaluminum dichloride Genylated alkylaluminum; dialkylaluminum hydride such as diethylaluminum hydride, dibutylaluminum hydride; other partially hydrided alkylaluminum such as alkylaluminum dihydrides such as ethylaluminum dihydride and propylaluminum dihydride; ethyl Examples thereof include partially alkoxylated and halogenated alkylaluminum such as aluminum ethoxychloride, butylaluminum butokicyclolide, ethylaluminum ethoxybromid and the like.

M ² AlR ^a ₄ … [VIII]
In the formula [VIII], M ² is Li, Na or K, and ^Ra is a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms. Examples of such a compound include LiAl (C ₂ H ₅ ) ₄ and LiAl (C ₇ H ₁₅ ) ₄ .

Further, a compound similar to the compound represented by the general formula [VII] can also be used, and examples thereof include an organoaluminum compound in which two or more aluminum compounds are bonded via a nitrogen atom. Specific examples of such a compound include (C ₂ H ₅ ) ₂ AlN (C ₂ H ₅ ) Al (C ₂ H ₅ ) ₂ .

As the organoaluminum compound (b-3), trimethylaluminum and triisobutylaluminum are preferably used from the viewpoint of availability.
The organoaluminum compound (b-3) may be used alone or in combination of two or more.

<Polymerization conditions>
The copolymer (A) can be suitably produced by copolymerizing ethylene and 1-butene in the presence of the above-mentioned catalyst for olefin polymerization. The copolymerization is not particularly limited, but is preferably carried out by solution polymerization in the presence of a catalyst for olefin polymerization at a temperature of 50 to 180 ° C. in the presence of a solvent.

At the time of polymerization, the usage and the order of addition of each component are arbitrarily selected. For example, a method of adding the catalyst component [A] and the catalyst component [B] to the polymer in any order can be exemplified. .. In the above method, two or more of each catalyst component may be contacted in advance.

When the copolymer (A) is produced by copolymerizing ethylene and 1-butene using a catalyst for olefin polymerization, the catalyst component [A] is usually 1 × 10 ^-9 to 1 liter per liter of the reaction volume. It can be used in an amount of 1 × 10 ^-1 mol, preferably 1 × 10 ^-8 to 1 × 10 ^{−2 mol.}

The molar ratio [(b-1) / M] of the component (b-1) to all the transition metal atoms (M) in the component [A] is usually 1 to 10000, preferably 10. It can be used in an amount such that it becomes ~ 5000. The molar ratio [(b-2) / M] of the component (b-2) to all the transition metal atoms (M) in the component [A] is usually 0.5 to 50. It can be used in an amount preferably 1 to 20. The component (b-3) can be used in an amount usually 0 to 5 mmol, preferably about 0 to 2 mmol per liter of polymerization volume.

The charged molar ratio of ethylene and 1-butene may be appropriately selected according to the characteristics of the target copolymer (A), and is not particularly limited. Usually ethylene: 1-butene = 10: 90-99.9: 0.1, preferably ethylene: 1-butene = 30: 70-99.9: 0.1, more preferably ethylene: 1-butene = 50 :. 50-98.0: 2.0.

"Solution polymerization", which is preferably used in the production of the copolymer (A), is a general term for a method of polymerizing a polymer in a state of being dissolved in a hydrocarbon solvent inert to the copolymerization reaction. The polymerization temperature in solution polymerization is usually 50 to 180 ° C, preferably 70 to 150 ° C, and more preferably 90 to 130 ° C.

In solution polymerization, when the polymerization temperature is in the above range, it is preferable from the viewpoint of polymerization activity, removal of heat of polymerization, and reduction of the amount of double bonds in the copolymer (A). Specifically, when it is at least the lower limit of the above range, it is preferable from the viewpoint of productivity; when it is at least the upper limit of the above range, branching is less likely to occur in the polymer and it is preferable from the viewpoint of blocking resistance.

The polymerization pressure is usually under normal pressure to 10 MPa gauge pressure, preferably normal pressure to 8 MPa gauge pressure, and the copolymerization can be carried out by any of batch type, semi-continuous type and continuous type. The reaction time (average residence time when the copolymerization reaction is carried out by a continuous method) varies depending on conditions such as catalyst concentration and polymerization temperature and can be appropriately selected, but is usually 1 minute to 3 hours, preferably 1 minute to 3 hours. 10 minutes to 2.5 hours.

It is also possible to carry out the polymerization in two or more stages having different reaction conditions.
The molecular weight of the obtained copolymer (A) can also be adjusted by changing the hydrogen concentration and the polymerization temperature in the polymerization system. Further, it can be adjusted by the amount of the catalyst component [B] used. When hydrogen is added to the polymerization system, the amount thereof is appropriately about 0.001 to 5,000 NL per 1 kg of the copolymer (A) produced. Further, the density of the obtained copolymer (A) can be adjusted by the feed amount of α-olefin, and the double bond amount can be reduced by appropriately setting the polymerization temperature and the polymerization catalyst.

The solvent used in the solution polymerization is usually an inert hydrocarbon solvent, preferably a saturated hydrocarbon having a boiling point of 50 to 200 ° C. under normal pressure. Specific examples thereof include aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane and kerosene; and alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane. Aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethylene chloride, chlorobenzene and dichloromethane also fall into the category of "inert hydrocarbon solvents" and do not limit their use.

In order to suppress variations in physical property values, the copolymer (A) obtained by the polymerization reaction and other components added as desired may be melted by an arbitrary method and subjected to kneading, granulation, or the like. preferable.

<Adhesive imparting agent>
The adhesive of the present invention may contain a tackifier, if necessary.
The tackifier is selected from, for example, natural rosin, modified rosin, polyterpene resin, synthetic petroleum resin, kumaron resin, phenol resin, xylene resin, styrene resin, low molecular weight styrene resin, and isoprene resin. At least one kind of resin can be mentioned. Among these, rosin-based resins, polyterpene-based resins, and synthetic petroleum resins are preferable, and those having an aliphatic and / or alicyclic structure are more preferable.

Here, as particularly preferable petroleum resins having an aliphatic and / or alicyclic structure, partially and completely hydrogenated rosins and their derivatives are used for rosin-based resins, and cyclic terpene homopolymers or copolymers or copolymers are used for polyterpene-based resins. Examples of coalesced and synthetic petroleum resins include aliphatic petroleum resins, alicyclic petroleum resins, aliphatic-aliphatic copolymer resins, and hydrogenated products of copolymers of naphtha-decomposed oil and various terpenes.

The tackifier preferably has a softening point in the range of 25 to 160 ° C. When the softening point is 25 ° C. or higher, bleeding to the surface can be prevented, and when the softening point is 160 ° C. or lower, the viscosity at the time of melting does not become too high and the workability is good. Specifically, the product names "Arcon P-70", "Arcon P-90", "Arcon P-100", "Arcon P-115", "Arcon P-125", "Arcon P-140" (and above) , Both manufactured by Arakawa Chemical Industry Co., Ltd. are preferably used.
The tackifier may be used alone or in combination of two or more.

<Wax>
The adhesive of the present invention may contain wax if necessary.
Examples of the wax include synthetic waxes such as Fisher Tropsch wax, polyethylene wax, polypropylene wax and atactic polypropylene, petroleum waxes such as paraffin wax and microcrystallin wax, and natural waxes such as wood wax, carnauba wax and honey wax.

The wax has a B-type viscosity (140 ° C., 6.0 rpm), preferably 10 to 8000 mPa · s, and more preferably 100 to 1000 mPa · s. When the B-type viscosity is in the above range, it is preferable in terms of cohesive force and kneading workability.

The wax has a melting point measured by DSC, preferably 80 to 150 ° C, more preferably 90 to 140 ° C. When the melting point is in the above range, it is preferable in terms of flexibility and kneading processability when using the adhesive.

Examples of commercially available wax products include the trade name "Mitsui High Wax 420P" and the trade name "Mitsui High Wax NL100" (all manufactured by Mitsui Chemicals, Inc.).
One type of wax may be used alone, or two or more types may be used in combination.

<Other additives>
The adhesive of the present invention includes conventionally known fluidity modifiers, nucleating agents, antioxidants, heat stabilizers, ultraviolet absorbers, light stabilizers, pigments, dyes, antibacterial agents, and fungicides, if necessary. At least one additive selected from plasticizers and fillers such as molds, antistatic agents, foaming agents, foaming aids, and mineral oils can be added as long as the object of the present invention is not impaired.

[Preparation and use of adhesive]
The adhesive of the present invention is, for example, a method of melting and mixing each component in order in a melting and melting tank such as a heating type melting and stirring tank, preferably under vacuum, under a nitrogen stream, and by rotating a stirring blade. It can be obtained by a method of melting and mixing by applying a shear under heating with a twin-shaped rotating blade, a method of melting and mixing with a screw of a single-screw or twin-screw extruder, and the like. The temperature is usually adjusted at 120-230 ° C, preferably 150-200 ° C. The veil-shaped or pellet-shaped sample thus produced can be used for various purposes.

In the case of a hot melt adhesive, the adherend may be bonded before the adhesive is cured, but the hot melt adhesive once cured is heated again to activate it, and then the adherend is bonded. You can also do it. Examples of the shape of the hot melt adhesive itself once cured include a sheet shape, a film shape, a non-woven fabric shape, a small piece shape, and a rod shape.

In the adhesive of the present invention, the content of the ethylene / 1-butene copolymer (A) is usually 10 to 90% by mass, preferably 15 to 70% by mass, and more preferably 20 to 20 to the total amount of the adhesive. It is 50% by mass. When the content is in the above range, it is preferable from the viewpoint of adhesiveness and coatability of the adhesive.

In the adhesive of the present invention, when a tackifier is used, the content thereof is preferably 50 to 200 parts by mass, more preferably 70 to 70 parts by mass with respect to 100 parts by mass of the ethylene / 1-butene copolymer (A). It is 150 parts by mass. When the adhesive of the present invention is formed with such a composition, various physical properties such as flexibility, mechanical properties, heat resistance, and adhesiveness can be obtained in a well-balanced manner.

In the adhesive of the present invention, when wax is used, the content thereof is preferably 50 to 200 parts by mass, more preferably 70 to 150 parts by mass with respect to 100 parts by mass of the ethylene / 1-butene copolymer (A). It is a department. When the wax content is in the above range, it is preferable in terms of adhesiveness and flexibility.

The application of the hot melt adhesive is not particularly limited as long as the object of the present invention can be achieved, but a commercially available hot melt applicator is widely used. Types of hot melt applicators include slot coater coating, roll coater coating, spiral coating that can be applied spirally, omega coating and control seam coating that can be applied in a wavy shape, slot spray coating and curtain spray coating that can be applied in a planar shape, and punctate coating. Examples include dot coating that can be applied to the surface, bead coating that can be applied linearly, and the like. A particularly preferable application target of the hot melt adhesive is adhesion between cardboards.

As a method of using the adhesive of the present invention as a hot melt adhesive, the obtained hot melt adhesive is formed into a sheet by a screw type extruder having a die portion called a T-die method, an inflation method, a calendar method, and a spinning method. , Formed into a film or non-woven fabric, fixed in the middle of the adherends to be laminated and bonded, and heat-bonded, or the adhesive formed into a sheet is heat-melted on one adherend and left as it is on the other. There is an adhesive method in which the adherend is crimped while cooling. Further, a method in which the adhesive of the present invention is melted by the screw type extruder, and the adhesive is directly inserted between the adherends to be laminated and heat-bonded without the above-mentioned molding process, one of the adherends. When the body is a thermoplastic, there are a method of directly adhering by coextrusion or a method of directly applying to one of the adherends and heat-adhering again.

The adhesive of the present invention is, for example, adhesion between base materials made of polyolefin resin or the like, the base material and a metal material (eg, metal plate, metal foil, metal mesh) or other material (eg, non-woven fabric, woven cloth, etc.). It can be suitably used for adhesion to cloth, paper such as cardboard, glass), and adhesion between the metal material or the other materials. Among them, it can be particularly preferably used for adhesion between corrugated cardboard and other adherends, or between corrugated cardboard and corrugated cardboard.

Examples of the base material made of the polyolefin resin or the like include polyolefin resin (eg, polyethylene, polypropylene), polyester resin, polycarbonate resin, polyarylate resin, acrylic resin, polyphenylene sulfide resin, polystyrene resin, vinyl resin, vinyl chloride resin, and the like. Examples thereof include a single-layer or laminated resin sheet such as a polyimide resin and an epoxy resin.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples. In the description of the following examples and the like, "parts" means "parts by mass" unless otherwise specified.

The method for measuring the physical properties of the ethylene / 1-butene copolymer and the like is as follows.

<Weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn)>
The weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were measured by a gel permeation chromatography (GPC) method using a gel permeation chromatograph Alliance GPC-2000 manufactured by Waters Corp. as follows. The separation columns consisted of two TSKgel GNH6-HT and two TSKgel GNH6-HTL, both of which had a column size of 7.5 mm in diameter and 300 mm in length, a column temperature of 140 ° C., and a mobile phase. Using o-dichlorobenzene (Fujifilm Wako Pure Chemical Industries, Ltd.) (containing 0.025% by mass of dibutylhydroxytoluene (BHT) (Takeda Pharmaceutical Company Limited) as an antioxidant), transfer the sample at 1.0 ml / min. The concentration was 15 mg / 10 ml, the sample injection volume was 500 μl, and a differential refraction meter was used as a detector. As the standard polystyrene, Tosoh Co., Ltd. was used for the molecular weights of Mw <1000 and Mw> 4 × 10 ⁶ , and Pressure Chemical Co., Ltd. was used for ^{1000 ≦ Mw ≦ 4 × 10 6.}

<Density>
Density was measured at 23 ° C. according to ASTM D1505.

<Double bond amount>
^{The amount of double bond was quantified by 1} H-NMR measurement of ethylene / 1-butene copolymer or the like (“ECX400P type nuclear magnetic resonance apparatus” manufactured by JEOL Ltd.). Vinyl-type double bonds, vinylidene-type double bonds, 2-substituted olefin-type double bonds, and 3-substituted olefin-type double bonds are observed as signals derived from the double bonds. The amount of double bond was quantified from the integrated intensity of each signal. The main chain methylene signal of ethylene / 1-butene copolymer was used as a chemical shift standard (1.2 ppm). The total amount of double bonds was calculated as the sum of each double bond.

In each equation, * indicates a bond with an atom other than a hydrogen atom.
The peaks of each hydrogen atom a to e are observed in the vicinity of the following.
-Peak of hydrogen atom a: 4.60 ppm
-Peak of hydrogen atom b: 4.85 ppm
-Peak of hydrogen atom c: 5.10 ppm
-Peak of hydrogen atom d: 5.25 ppm
-Peak of hydrogen atom e: 5.70 ppm

The quantitative formula for the amount of double bond is as follows.
-Vinyl type double bond amount = {(integral strength of signal b) + (integral strength of signal e)} / 3
-Vinylidene type double bond amount = (integral intensity of signal a) / 2
-Disubstituted olefin type double bond amount = (integrated intensity of signal d) / 2
-Tri-substituted olefin type double bond amount = (integral intensity of signal c)

<MFR>
MFR was measured according to ASTMD-1238 at 190 ° C. and a load of 2.16 kg.

<Comonomer content (composition)>
¹³ The content of structural units derived from 1-butene was determined to the precision of one decimal place by analysis of the C-NMR spectrum.

<Mechanical strength of polymer>
(Breaking point strength, breaking point elongation)
In accordance with ASTM D638, the breaking point strength and breaking point elongation were measured with a 2 mmt press sheet.
(surface hardness)
According to ASTM D2240, two 2 mmt press sheets were superposed and the Shore A hardness was measured.

[Manufacturing Example 1]
Hexane slurry of triphenylcarbenium tetrakis (pentafluorophenyl) borate as a co-catalyst was 0.0065 mmol / hr as a main catalyst, and bis (1, Hexane slurry of 3-dimethylcyclopentadienyl) zirconium dichloride is supplied at a ratio of 0.0013 mmol / hr, and a hexane solution of triisobutylaluminum is supplied at a ratio of 1.5 mmol / hr, and dehydration-purified normal hexane is used as a catalyst solution and a polymerization solvent. Normal hexane that had been dehydrated and purified so that the total amount of hexane was 21.3 L / hr was continuously supplied. At the same time, ethylene was continuously supplied to the polymerizer at a ratio of 6.3 kg / hr for ethylene, 5.5 kg / hr for 1-butene, and 210 NL / hr for hydrogen, and the polymerization temperature was 110 ° C., the total pressure was 3.2 MPaG, and the residence time was 35 minutes. Continuous solution polymerization was carried out under the conditions of. The normal hexane mixed solution of the ethylene / 1-butene copolymer produced in the polymer was continuously discharged through the discharge port provided on the side of the polymer. Methanol was injected at a rate of about 0.75 L / hr to join the ethylene / 1-butene copolymer in a normal hexane mixed solution to stop the polymerization, and then the mixture was transferred into a flash tank. The pressure in the flash tank was about 0.1 MPaG, and the temperature of the steam part in the flash tank was about 180 ° C. Then, it was pelletized through a twin-screw extruder whose die temperature was set to 180 ° C. to obtain an ethylene / 1-butene copolymer (polymer A) as pellets. The yield was 5.1 kg / hr. The physical characteristics of Polymer A are shown in Table 1.

[Manufacturing Examples 2 to 4]
Ethylene 1-butene copolymers (polymers B, C, D) were prepared in the same manner as in Production Example 1 except that the ethylene feed amount, 1-butene feed amount and hydrogen feed amount were appropriately changed in Production Example 1. Obtained. The physical characteristics of the polymers B, C, and D are shown in Table 1.

[Polymer E]
As the polymer E, an ethylene / 1-octene copolymer "Affinity GA1950" (manufactured by Dow Chemical Co., Ltd.) was prepared. The physical characteristics of Polymer E are shown in Table 1.

It can be seen that the ethylene / 1-butene copolymer is excellent in flexibility and elongation as the 1-butene content increases.
[Example 1]
In a flask heated to 150 ° C., 40 parts by mass of the polymer A obtained in Production Example 1, 30 parts by mass of the tackifier, and 30 parts by mass of wax were put into the flask, a stirring blade was put in, and the rotation speed was 50 rpm. And mixed at a temperature of 150 ° C. for 10 minutes to prepare an adhesive. Archon P-125 (manufactured by Arakawa Chemical Industry Co., Ltd .; commercially available product) was used as the tackifier. As the wax, Mitsui High Wax NL100 (manufactured by Mitsui Chemicals, Inc .; polyethylene type, density = 920 kg / m ³ , melting point = 103 ° C., B-type viscosity (140 ° C., 6.0 rpm) = 200 mPa · s) was used.

[Examples 2 and 3, Comparative Examples 1 and 2]
An adhesive was prepared in the same manner as in Example 1 except that the type of polymer was changed as shown in Table 2.

[Adhesion evaluation]
Using a hand gun for applying hot melt adhesive (trade name "GX600Pro", manufactured by Technos Co., Ltd.) that heated the adhesive obtained above to 180 ° C, a commercially available cardboard box (width 15 mm x length 100 mm x thickness). 5 mm), coated in a columnar shape with a diameter of 1 mm and a length of 15 mm under the condition of a test environment temperature of 23 ° C. and an open time of 2 seconds, and then bonded to a cardboard of the same shape and solidified under the condition of a set time of 1 second. Then, a test piece made by laminating two cardboard boxes of the same shape was obtained.

In order to evaluate the adhesiveness of the adhesive, a T-peel peeling test (based on JIS K6854-3, peeling speed 50 mm / min, test environment temperature 23 ° C) was carried out to determine the state of destruction of the base material (cardboard) and the adhesive. confirmed. The case where the base material was broken was described as "AA", and the case where a part of the adhesive was broken was described as "BB". When the base material is broken, it indicates that the adhesive force of the adhesive to the base material and the cohesive force of the adhesive itself are superior to the cohesive force of the base material.

In order to evaluate the adhesive's ability to follow the deformation of the adherend, the test piece is bent at one place and returned to its original position 10 times. Similarly, the T-peel peeling test (compliant with JIS K6854-3, peeling speed 50 mm) / Min, test temperature 23 ° C.) was carried out, and the broken state of the base material (cardboard) and the adhesive was confirmed. The case where the base material was broken was described as "AA", and the case where a part of the adhesive was broken was described as "BB".

[Evaluation of heating stability]
50 g of the adhesive obtained above was placed in a 100 ml beaker and stored in air at 180 ° C., and the hue change of the adhesive was observed. Immediately after putting the adhesive in the beaker, the hues after 1 week and 2 weeks were confirmed.

Claims (7)

An adhesive containing an ethylene / 1-butene copolymer (A) that satisfies all of the following requirements (A-1) to (A-4).
(A-1) The MFR measured at 190 ° C. and a load of 2.16 kg is 0.1 to 50 g / 10 minutes.
(A-2) The density is 855 to 900 kg / m ³ .
(A-3) The content of the structural unit derived from 1-butene is 6 to 25 mol%.
^{(A-4) 1 H-} NMR vinyl type double bond number per 1000 carbon which is determined by measurement, vinylidene-type double bonds, disubstituted olefinic double bonds and 3 the total content of substituted olefinic double bonds However, it is less than 0.5. Vinyl type double bond, vinylidene type double bond, disubstituted olefin type double bond and trisubstituted olefin type double bond per 1000 carbon atoms determined by ¹ H-NMR measurement of the copolymer (A). The adhesive according to claim 1, wherein the content of any of the double bonds is less than 0.2. The adhesive according to claim 1 or 2, wherein the MFR of the copolymer (A) measured at 190 ° C. and a load of 2.16 kg is 0.1 to 9 g / 10 minutes. The adhesive according to any one of claims 1 to ³ , wherein the copolymer (A) has a density of 855 to 875 kg / m 3. The adhesive according to any one of claims 1 to 4, wherein the content of the structural unit derived from 1-butene of the copolymer (A) is 15 to 25 mol%. The adhesive according to any one of claims 1 to 5, which comprises a tackifier and / or a wax. The adhesive according to any one of claims 1 to 6, which is a hot melt adhesive.