JP4818673B2 - Reactive hot melt adhesive - Google Patents

Description

  The present invention relates to a reactive hot melt adhesive. More specifically, the present invention relates to a reactive hot melt adhesive suitably used for a polyolefin-based substrate such as a polyethylene film, a polypropylene plate, and a polypropylene film.

The hot-melt adhesive is a solid and solvent-free type, and is easy to use and useful because it can be used only with a heating operation. Reactive hot melt adhesives have attracted attention in recent years as further improved in heat resistance and adhesiveness.
Conventionally, as a reactive hot melt adhesive excellent in adhesiveness to a polyolefin-based substrate, one comprising a urethane prepolymer and a metallocene polyolefin is known (for example, Patent Document 1).
JP 2004-10809 A

However, this reactive hot melt adhesive has excellent adhesion to polyolefin base materials, but the compatibility between the urethane prepolymer and the metallocene polyolefin is poor, and in use, it is left in a molten state in a molten tank for a long time. Then, phase separation may occur, and after heating and melting, it must be used in a short time, and there is a limitation in use.
The purpose of the present invention is to provide a reactive hot melt that has excellent initial adhesive strength by ensuring adhesion to polyolefin base materials, improving stability during heating and melting, and increasing resin strength before curing. It is to provide an adhesive.

The inventor of the present invention has arrived at the present invention as a result of intensive studies to solve the above problems.
That is, the polyisocyanate (A), a polyolefin polyol below (B1), polybutadiene polyol, polyisoprene polyol, at least one number average selected from the group consisting of hydrogenated polybutadiene polyol and hydrogenated polyisoprene polyol urethane prepolymer molecular weight is by reacting a polyolefin polyol (B2) of 200 to 4,000, and a reactive hot-melt adhesive, characterized by comprising the olefin resin (C).
(B1): α, β-unsaturated carboxylic acid (anhydride) is added to the double bond of the olefin resin (D) having a terminal double bond, and the imidation reaction between the introduced carbonyl group and hydroxylamine A hydroxyl group-containing polyolefin-based resin obtained by:

  The reactive hot melt adhesive of the present invention is improved in stability at the time of heating and melting compared to the conventional reactive hot melt adhesive comprising a urethane prepolymer and a metallocene polyolefin in application to a polyolefin-based substrate. There is an effect that the initial adhesive force is also excellent.

In the present invention, the polyisocyanate (A) is an aromatic polyisocyanate having 6 to 20 carbon atoms (excluding carbon in the NCO group, the same shall apply hereinafter), an aliphatic polyisocyanate having 2 to 18 carbon atoms, or 4 to 15 carbon atoms. Alicyclic polyisocyanates, araliphatic polyisocyanates having 8 to 15 carbon atoms, modified products of these polyisocyanates, and mixtures of two or more of these.
Specific examples of the aromatic polyisocyanate include 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6-tolylene diisocyanate (TDI), crude TDI, and 2,4′-. And / or 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4,4′-diisocyanatobiphenyl, 3,3′-dimethyl-4, Examples include 4'-diisocyanatodiphenylmethane, crude MDI, 1,5-naphthylene diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, m- and p-isocyanatophenylsulfonyl isocyanate.

Specific examples of the aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine. Diisocyanate, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate, etc. Is mentioned.
Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4′-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2- And isocyanatoethyl) -4-cyclohexene-1,2-dicarboxylate, 2,5- and / or 2,6-norbornane diisocyanate.

Specific examples of the araliphatic polyisocyanate include m- and / or p-xylylene diisocyanate (XDI), α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI), and the like.
Examples of modified polyisocyanates include modified MDIs (urethane-modified MDI, carbodiimide-modified MDI, trihydrocarbyl phosphate-modified MDI), urethane-modified TDI, biuret-modified HDI, isocyanurate-modified HDI, and isocyanurate-modified IPDI. And a mixture of two or more thereof [for example, combined use of modified MDI and urethane-modified TDI (isocyanate-containing prepolymer)].
Of these, IPDI, TDI, XDI and TMXDI are preferred, and HDI and MDI are particularly preferred.

  The polyolefin-based polyol (B1) is obtained by adding an α, β-unsaturated carboxylic acid (anhydride) to the double bond of the olefin resin (D) having a terminal double bond, and introducing the introduced carbonyl group, hydroxylamine, It is a hydroxyl group-containing polyolefin resin obtained by the imidization reaction, and may be used as a mixture of two or more polyolefin polyols contained in (B1).

  The (D) is a polyolefin having a double bond at one terminal and / or both terminals, and can be obtained by polymerization of one or a mixture of two or more olefins having 2 to 30 carbon atoms. Among the olefins having 2 to 30 carbon atoms, ethylene, propylene, 1-butene and a mixture of two or more thereof are preferable. The average number of terminal double bonds in one molecule is preferably 1 to 3. The average number of terminal double bonds can be calculated from the iodine value and the number average molecular weight. The number average molecular weight is preferably 3,000 to 100,000, more preferably 5,000 to 50,000. The number average molecular weight is a value obtained by the GPC method. This (D) may or may not contain one hydroxyl group that reacts with an isocyanate group. As (D), for example, “Yukatak-K4”, “Yukatak-K8” manufactured by Tarui Chemical Co., Ltd. can be used.

The number average molecular weight can be measured by a gel permeation chromatography method (GPC method). For example, it can be measured under the following conditions. Equipment: High-temperature gel permeation chromatography Solvent: Orthodichlorobenzene reference material: Polystyrene sample concentration: 3 mg / ml
Column temperature: 135 ° C

Examples of the α, β-unsaturated carboxylic acid (anhydride) include monocarboxylic acids having 3 to 12 carbon atoms, dicarboxylic acids, and anhydrides thereof. Specific examples include (meth) acrylic acid, maleic acid (anhydride), fumaric acid, itaconic acid (anhydride), and citraconic acid (anhydride). Among these, maleic acid (anhydride) and fumaric acid are preferable, and maleic acid (anhydride) is particularly preferable.
The amount of α, β-unsaturated carboxylic acid (anhydride) used in the reaction is preferably 0.5 to 40% by weight, more preferably 1 to 30% by weight, based on the weight of (D). In the reaction with α, β-unsaturated carboxylic acid (anhydride), the terminal double bond of (D) is subjected to α, β-unsaturated carboxylic acid (anhydride) by either the solution method or the melt method. ) Is thermally added (ene reaction). The reaction temperature is preferably 170 to 230 ° C. The reaction time is preferably 1 to 10 hours. The reaction can be measured by acid value, and the end point is the point at which the change in acid value measured every 30 minutes becomes 0.1 or less.

  The hydroxylamine used in the reaction of the reaction product of (D) with an α, β-unsaturated carboxylic acid (anhydride) with the carbonyl group is a hydroxylamine having 2 to 10 carbon atoms, such as 2-aminoethanol. , 3-aminopropanol, 1-amino-2-propanol, 4-aminobutanol, 5-aminopentanol, 6-aminohexanol, 3-aminomethyl-3,5,5-trimethylcyclohexanol and the like. Of these, 2-aminoethanol is preferred. The reaction with hydroxylamine can be carried out by directly reacting the reaction product of (D) with an α, β-unsaturated carboxylic acid (anhydride) with hydroxylamine to produce an imidized product. The reaction temperature is preferably 120 to 230 ° C. The reaction time is preferably 1 to 10 hours. The reaction can be measured by amine value, and the end point is the point at which the change in amine value measured every 30 minutes is 0.1 or less. The amount of hydroxyl groups of hydroxylamine is 0.1 to 2, preferably 0.3 to 1.5, particularly preferably 0.5 to 1.2, most preferably 1 per carbonyl group. is there.

  The hydroxyl value of (B1) is preferably 4 to 280, more preferably 4 to 100. The number average molecular weight is preferably 3,000 to 100,000, more preferably 5,000 to 50,000.

Examples of the low molecular weight polyolefin-based polyol (B2) include polybutadiene polyol, polyisoprene polyol, hydrogenated polybutadiene polyol, hydrogenated polyisoprene polyol, and mixtures of two or more thereof.
Among these, hydrogenated polybutadiene polyol and hydrogenated polyisoprene polyol are preferable, and hydrogenated polybutadiene polyol is more preferable.
The number of hydroxyl groups in the molecule is preferably 1 to 4, more preferably 2 to 3. A hydroxyl value becomes like this. Preferably it is 5-1200, More preferably, it is 22-340.
The number average molecular weight is preferably 200 to 4,000, more preferably 500 to 3,000. The number average molecular weight is a value obtained by the GPC method.
Examples of the hydrogenated polybutadiene polyol include “NISSO PB GI-1000” and “NISSO PB GI-2000” manufactured by Nippon Soda Co., Ltd.

  The equivalent ratio of the total OH / (A) NCO (isocyanate) of (B1) and (B2) is preferably 1 / 1.01 to 1/5, more preferably 1 / 1.2 to 1/4. Especially preferably, it is 1 / 1.5-1 / 3. By making (A) excessive, it becomes an NCO-terminated urethane prepolymer and has reactivity when used as a hot melt adhesive.

  The blending ratio of (B1) and (B2) is preferably 20 to 95% by weight, more preferably 50 to 90% by weight with respect to the total amount of (B1) and (B2). When (B1) is 20% by weight or more, the compatibility is good, the cohesive strength of the resin is increased, and the initial adhesive strength of the resulting adhesive is good. When (B1) is 95% by weight or less, there is no problem that the adhesive strength after curing of the obtained adhesive is reduced. When (B2) is 5% by weight or more, the adhesive strength after curing of the obtained adhesive is good, and when (B2) is 80% by weight or less, the compatibility and initial adhesive strength of the obtained adhesive are reduced. there is no problem.

The olefin resin (C) can be obtained by polymerization of one or a mixture of two or more olefins having 2 to 30 carbon atoms. Specifically, in addition to the above (D), ethylene, propylene, 1- Polymers having no double bond at the terminal, ethylene / propylene / butadiene copolymers and ethylene / propylene / dicyclopentadiene copolymers obtained by polymerization of butene and a mixture of two or more thereof, the above (co) heavy Examples thereof include a silane-modified product of a combination.
Among these, specifically preferred are ethylene homopolymers, 1-butene homopolymers, ethylene / propylene copolymers, and silane-modified products of propylene / 1-butene copolymers, and more preferred are , Propylene homopolymer, propylene / 1-butene copolymer, ethylene / propylene / 1-butene copolymer, silane modified product of propylene / 1-butene copolymer, ethylene / propylene / 1-butene copolymer Silane modified product and (D) above. The number average molecular weight is preferably 3,000 to 100,000, more preferably 5,000 to 50,000. The number average molecular weight is a value obtained by the GPC method.
(C) is, for example, “Yukatak-K8” (Propylene homopolymer having a terminal double bond) manufactured by Tarui Chemical Co., Ltd., “VESTOPLAST 704” (ethylene / propylene / 1-butene copolymer) manufactured by Degussa Japan, “ VESTOPLAST 206 "(modified silane of ethylene / propylene / 1-butene copolymer) and the like can be used.

  The blending ratio of (C) is preferably 10 to 90% by weight, more preferably 20 to 80% by weight with respect to the total amount of (A), (B1), (B2) and (C). It is. When (C) is 90% by weight or less, there is no problem that the heat resistance of the obtained adhesive is lowered, and when it is 10% by weight or more, the adhesiveness of the obtained adhesive to the polyolefin-based substrate is lowered. There is no problem.

The production method of the urethane prepolymer is not particularly limited and can be produced by a usual method. Specifically, the following two methods are preferable.
(I): A method in which (A) is reacted with (B1) and (B2), and then (C) is kneaded and manufactured.
(Ii) A process for producing a mixture of (B1), (B2) and (C) and (A).
Of the above methods, the method (ii) is more preferable from the viewpoint of the simplicity of the production process and the thermal stability of the resulting adhesive.

When the urethane prepolymer is produced, a urethanization catalyst may be used. As the urethanization catalyst, those conventionally used for polyurethane production can be used.
Metal catalysts such as tin catalysts [trimethyltin laurate, trimethyltin hydroxide, dimethyltin dilaurate, dibutyltin diacetate, dibutyltin dilaurate, stannous octoate, dibutyltin maleate, etc.], lead catalysts [lead oleate, 2-ethylhexanoate, lead naphthenate, lead octenoate, etc.], other metal catalysts [naphthalic acid metal salts such as cobalt naphthenate, phenylmercury propionate, etc.]; and amine catalysts such as triethylenediamine, tetramethyl Ethylenediamine, tetramethylhexylenediamine, diazabicycloalkenes [1,8-diazabicyclo [5,4,0] undecene-7 [DBU (manufactured by San Apro, registered trademark)], etc.]; dialkylaminoalkylamines [dimethyl Aminoethylamine Dimethylaminopropylamine, diethylaminopropylamine, dibutylaminoethylamine, dimethylaminooctylamine, dipropylaminopropylamine, etc.] or heterocyclic aminoalkylamines [2- (1-aziridinyl) ethylamine, 4- (1-piperidinyl) 2-hexylamine etc.] carbonates and organic acid salts (formate etc.), etc .; N-methylmorpholine, N-ethylmorpholine, triethylamine, diethylethanolamine, dimethylethanolamine etc .; and combinations of two or more of these System.

The amount of urethanization catalyst used is preferably 1% or less, more preferably 0.05% or less, and particularly preferably 0.01% or less, based on the total weight of (A) to (C). If it is 1% or less, the thermal stability of the finally obtained adhesive will not be impaired.
As the reaction conditions, for example, (A) to (C) and a urethanization catalyst are charged in a reaction vessel having a temperature control function, and reacted continuously at a temperature of preferably 50 to 200 ° C. for 30 to 1,000 minutes. Alternatively, (A) to (C) and the urethanization catalyst are poured into a biaxial excluder and preferably reacted continuously at a temperature of 100 to 220 ° C.
The content of isocyanato groups (NCO) in the urethane prepolymer comprising (A) to (C) is preferably 0.2 to 10% by weight, more preferably 0.5 to 5.0% by weight. It is. When it is 0.2% by weight or more, the heat resistance is good, and when it is 10% by weight or less, the thermal stability at the time of heating and melting is good.

The hot melt adhesive of the present invention can contain a tackifying resin for the purpose of improving the initial adhesive strength in the urethane prepolymer production process or at any stage after production.
As the tackifying resin, those generally used for hot melt adhesives can be used, and examples thereof include petroleum resins, rosin resins, terpene resins, coumarone resins, and xylene resins. The number average molecular weight of these resins is not particularly limited, but is preferably 200 or more and 15,000 or less, more preferably 300 or more and 5,000 or less.
Examples of petroleum resins include aliphatic petroleum resins (polymers mainly composed of C4 to C5 mono- or diolefins such as isobutylene, butadiene, 1,3-pentadiene, isoprene, and piperidine), and alicyclic petroleum resins (spent C4). Resin obtained by cyclization and dimerization polymerization of diene component in C5 fraction, resin hydrogenated with aromatic hydrocarbon resin, etc., aromatic petroleum resin (vinyl toluene, indene, α-methylstyrene, C9, etc.) ˜C10 vinyl aromatic hydrocarbon as a main component, etc.), petroleum resins such as aliphatic-aromatic copolymers, and hydrogenated products thereof. When tackifying resin has active hydrogen, it can also be integrated in a urethane prepolymer by making it react with (A).

The ring-and-ball method softening point of the tackifying resin (measurement method: conforming to JAI-7-1991) is selected depending on the use temperature of the adhesive, but is preferably 30 to 160 ° C, more preferably 60 to 140 ° C. .
If a liquid at room temperature is used alone, the cohesive force may be too low, but it can be used in combination with a solid at room temperature.
The addition amount of the tackifying resin is preferably 0 to 70%, more preferably 0 to 50%, and particularly preferably 0 to 30% by weight with respect to the entire hot melt adhesive of the present invention. . When the addition amount is 70% or less, the adhesive strength is good.

The hot melt adhesive of the present invention may contain a softening agent for the purpose of adjusting the viscosity, the adhesive strength, the solidification speed, etc., in the urethane prepolymer production process or any stage after production.
Examples of the softening agent include process oil, plasticizer, liquid rubber, and wax. These may be used alone or in combination of two or more. A softener is a liquid or solid at room temperature and melts at the time of use to lower the melt viscosity of a hot melt adhesive, plasticize it to give an adhesive force, or delay or accelerate the solidification rate. is there.
Examples of the process oil include those having a kinematic viscosity (100 ° C.) of 1 to 100 mm ² / s, such as paraffinic oil, naphthenic oil, and aroma oil.
Examples of the plasticizer include those having a weight average molecular weight of 100 to 5,000, such as phthalic acid ester, benzoic acid ester, phosphoric acid ester, aliphatic glycol polyester, and toluenesulfonamide. The weight average molecular weight can be measured by the GPC method.
Examples of the liquid rubber include those having a weight average molecular weight of 200 to 10,000, such as liquid polybutene, liquid polybutadiene, liquid polyisoprene, and hydrogenated products thereof.
Examples of the wax include those having a weight average molecular weight of 100 to 10,000, such as paraffin wax, microcrystalline wax, Fischer-Tropsch wax, polyethylene wax, polypropylene wax, and oxidized wax obtained by oxidative decomposition thereof, and Examples thereof include acid-modified waxes obtained by graft-modifying unsaturated carboxylic acids (anhydrides) such as (anhydrous) maleic acid, fumaric acid, and (meth) acrylic acid.

Furthermore, the reactive hot-melt adhesive of the present invention can be added to other resins within a range that does not impair the properties of the composition according to various purposes and applications in the production process of the urethane prepolymer or at any stage after the production. An agent can be optionally added.
Examples of the additive include pigments (eg, titanium oxide, carbon black, etc.), dyes, fillers (eg, talc, mica, calcium carbonate, etc.), nucleating agents (eg, sorbitol, phosphate metal salt, benzoic acid metal salt, Metal phosphates, etc.), lubricants (eg, calcium stearate, butyl stearate, oleic amide, etc.), mold release agents (eg, carboxyl-modified silicone oil, hydroxyl-modified silicone oil, etc.), antioxidants (eg, phenol-based) Antioxidants, phosphite antioxidants, thioether antioxidants, amine antioxidants, etc., light stabilizers (eg benzotriazole, hindered amine, benzoate etc.), UV absorbers (eg benzotriazole, benzophenone) , Triazines, etc.) and flame retardants (eg halogenes) System flame retardant, phosphorus-based flame retardant, antimony-based flame retardants, metal hydroxide-based flame retardant, etc.) and the like.

In the reaction of (A) with (B1) and (B2), in addition to the urethanization catalyst, softener, pigment, dye, filler, nucleating agent, lubricant, mold release agent, antioxidant, light stability You may contain an agent, a flame retardant, etc.
(A) + (B1) + (B2) + (C) in the reactive hot melt adhesive of the present invention
The amount of urethane prepolymer + (C)] is preferably 50 to 100% by weight, more preferably 60 to 100%, and particularly preferably 70 to 100%. When the amount of (A) + (B1) + (B2) + (C) is 50% or more, the adhesive strength is good.
In producing the hot melt adhesive of the present invention, it is sufficient that the constituent components of the adhesive can be heated, melted and kneaded, and ordinary hot melt production equipment can be used.
For example, a single screw or twin screw extruder, a sigma blade mixer, a ribbon blender, a butterfly mixer, a kneader and the like can be mentioned.
The mixing temperature is preferably 60 to 250 ° C., more preferably 80 to 200 ° C., and it is preferably performed in an inert gas atmosphere such as nitrogen gas for preventing resin deterioration.

The adhesive of the present invention thus obtained is appropriately formed into a desired shape such as a block, pellet, powder, sheet or film, and can be used as a hot melt adhesive.
The method for using the hot melt adhesive of the present invention is not particularly limited. For example, when the adhesive is in the form of a block or a pellet, the adhesive is melted and then bonded to a substrate to be bonded. Used by applying.

As an apparatus used for application, an applicator for a normal hot melt adhesive, [for example, a roll coater having a heatable melting tank (gravure roll, reverse roll, etc.), curtain coater, bead, spiral, spray, slot] and Extruders [for example, single screw extruders, twin screw extruders, kneader ruders, etc.].
In the case of an apparatus such as the former, an adhesive is applied to one or both of the adherends and bonded together before cooling and solidification, or after cooling and solidification, the adherends are combined, heated again, and bonded. When bonding, it is better to pressurize, and the pressure can be released after cooling and solidification.
In the case of an apparatus like the latter, it is extruded to one or both of the adherends, and after cooling and solidification, the adherends are combined, heated again, and bonded together. When bonding, it is better to pressurize, and the pressure can be released after cooling and solidification.
Moreover, it can coextrude between adherends and can perform bonding simultaneously.

When the adhesive is powder, it is used after being applied to the adherend and then heated and bonded. The heating temperature is not particularly limited, but is preferably 10 to 20 ° C. higher than the melting point (or softening point). When bonding, it is better to pressurize, and the pressure can be released after cooling and solidification. The pressure to be applied is not particularly limited as long as sufficient adhesion can be obtained, and is preferably 10 kPa to 5 MPa. The basis weight of the powder is not particularly limited as long as a desired adhesive force can be obtained, but is preferably 10 to 500 g / m ² .
When the adhesive is a sheet or a film, the adhesive is sandwiched between substrates to be bonded together, heated and melted and bonded, or placed on one or both, heated and melted, and before cooling and solidification Or after cooling and solidification, the adherends are combined, heated again and bonded together. The heating temperature at the time of heating and melting is not particularly limited, but is preferably higher by 10 to 20 ° C. than the melting point (or softening point), and the heating temperature at the time of heating again is not particularly limited, but the melting point (or The temperature is preferably 10 to 20 ° C. higher than the softening point). Moreover, it is better to pressurize when bonding, and the pressure can be released after cooling and solidification. The pressure to be applied is not particularly limited as long as a desired adhesive force can be obtained, and is preferably 10 kPa to 5 MPa.
The size of the sheet or film is not particularly limited as long as it has a desired area.
Although the thickness of a sheet | seat or a film does not have a restriction | limiting in particular, Preferably it is 10-500 micrometers, More preferably, it is 30-300 micrometers.

The curing reaction of the reactive hot melt adhesive of the present invention is triggered by the reaction between the contained isocyanate and the moisture in the air. The curing temperature is usually 5 ° C or higher, preferably 10 to 100 ° C. The humidity condition is preferably 20 to 100% R.D. H. And particularly preferably 30 to 80% R.V. H. It is. The curing time is several minutes to 200 hours.
The cured product thus obtained has good cured properties and is excellent in heat resistance, water resistance, solvent resistance and the like.

  The hot melt adhesive of the present invention can be suitably used for polyolefin-based substrates (polyethylene film, polypropylene plate, polypropylene film, etc.), but is not limited thereto.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to this. In the examples, “parts” represents parts by weight, and “%” represents% by weight.

(Description of abbreviations used in the following examples)
[B2-1]: “NISSO PB GI-1000” (manufactured by Nippon Soda Co., Ltd .; hydrogenated polybutadiene diol, hydroxyl value = 67.5, Mn = 1,500)
[B2-2]: “NISSO PB GI-2000” (manufactured by Nippon Soda Co., Ltd .; hydrogenated polybutadiene diol, hydroxyl value = 52.9, Mn = 2,100)
[C-1]: “Yukatak-K8” (manufactured by Tarui Chemical Co., Ltd .; propylene homopolymer having terminal double bonds, Mn = 6,000, average number of terminal double bonds per molecule = about 1.2)
[C-2]: “VESTOPLAST 206” (manufactured by Degussa Japan; modified silane of ethylene / propylene / 1-butene copolymer, Mn = 12,000)

[Production of polyolefin resin containing hydroxyl group (B1)]
Production Example 1
300.0 parts of “Yukatak-K8” (above) was charged into a separable flask equipped with a temperature control device, a dropping device, a stirring device, and an inlet, and the system was replaced with nitrogen so that the raw material could be melted and stirred. After that, stirring was started and the temperature was raised to 180 ° C. 4.7 parts of maleic anhydride was added from the inlet, 3.3 parts of dicumyl peroxide (28.6 wt% xylene solution) was added dropwise as an initiator over 10 minutes, and reacted at 180 ° C. for 2 hours. . After measuring the acid value and confirming the end point of the reaction, after cooling to 100 ° C., 200 parts of xylene and 3.0 parts of 2-aminoethanol were introduced from the inlet, the temperature was raised to 140 ° C., and further 2 at 140 ° C. Reacted for hours. The temperature was raised to 180 ° C., and xylene and unreacted substances were removed under a reduced pressure of 133 Pa or less. As a result, a hydroxyl group-containing polyolefin resin [B1-1] having an acid value of 0.2 and a hydroxyl value of 6.1 was obtained. Since the imide group was confirmed by IR measurement of [B1-1] and there was no unreacted product, it was confirmed that this hydroxyl group was due to imidization.

Production Example 2
In the same manner as in Production Example 1, 300.0 parts of “Yukatak-K8” (above) was charged into a separable flask and heated to 180 ° C. 14.2 parts of maleic anhydride was added from the inlet, and 9.9 parts of dicumyl peroxide (28.6% by weight xylene solution) was added dropwise over 10 minutes as an initiator and reacted at 180 ° C. for 2 hours. . After measuring the acid value and confirming the end point of the reaction, after cooling to 100 ° C., 200 parts of xylene and 16.0 parts of 2-aminoethanol were introduced from the inlet, the temperature was raised to 140 ° C., and 2 more at 140 ° C. Reacted for hours. The temperature was raised to 180 ° C., and xylene and unreacted substances were removed under a reduced pressure of 133 Pa or less. As a result, a hydroxyl group-containing polyolefin resin [B1-2] having an acid value of 0.3 and a hydroxyl value of 17.7 was obtained. Since the imide group was confirmed by IR measurement of [B1-2] and there was no unreacted product, it was confirmed that this hydroxyl group was due to imidization.

Example 1
[B1-1] 20.0 parts, [B2-1] 20.0 parts, [C-1] 53.5 parts were charged in a separable flask equipped with a temperature controller and a stirrer, and dissolved at 120 ° C. Dehydration under reduced pressure (120 ° C., 133 Pa, 1 hour) was performed. In a nitrogen atmosphere, 6.5 parts of MDI was charged, and after aging at 100 ° C. for 4 hours, the hot melt adhesive of the present invention (isocyanato group content (NCO%): 1.2%, 130 ° C. melt viscosity: 10, 000 mPa · s).

Examples 2-5, Comparative Examples 1 and 2
With the combinations and parts by weight of (A) to (C) as shown in Table 1, the same operations as in Example 1 were performed to obtain the hot melt adhesive of the present invention and the comparative hot melt adhesive, respectively. .

The following evaluations were performed using the examples and comparative examples. The results are shown in Table 2.
<Evaluation of sample>
1) Melt viscosity: The temperature of the hot melt adhesive to be evaluated was controlled at 130 ° C. for 15 minutes, and then measured using a B-type viscometer at the same temperature.
2) Compatibility 1; The hot melt adhesive to be evaluated was observed in a thermostat at 130 ° C. in an air atmosphere for 3 hours, and the state was observed and evaluated according to the following criteria.
○: No phase separation ×: Phase separation 3) Compatibility 2; After adjusting the temperature of the hot melt adhesive to be evaluated at 130 ° C. for 15 minutes, using a B-type viscometer at the same temperature, from the start of rotor rotation of the viscometer The viscosity after 5 minutes and the viscosity after 30 minutes from the start of rotation were measured, and the viscosity ratio after 30 minutes / 5 minutes was calculated. A value closer to 1 indicates better compatibility, no phase separation, and a stable viscosity.
4) Initial adhesive strength: Each hot melt adhesive to be evaluated was formed into a film having a thickness of 100 μm using a press molding machine (temperature 130 ° C.). The obtained film is applied to the adherend OPP.
The sheet was sandwiched between sheets (biaxially stretched polypropylene sheet, thickness 30 μm) and bonded under the conditions of a temperature of 130 ° C., a press pressure of 98 kPa, and a time of 30 seconds. After leaving at 23 ° C. and 50% RH for 30 minutes, the 180 ° peel strength was measured in the 23 ° C. atmosphere to obtain the initial adhesive strength.
The initial adhesive strength was measured using an autograph according to JIS K6854-1999 under the condition of a tensile speed of 50 mm / min.
5) Adhesion force after curing: After bonding in the same manner as in 4) and leaving for 1 week in an atmosphere of 23 ° C. and 50% RH, 180 ° peel strength was measured in an atmosphere of 23 ° C. as in 4).
6) High-temperature adhesive force after curing; after laminating in the same manner as in 4) and leaving for 1 week in a 23 ° C., 50% RH atmosphere, 180 ° peel strength was measured in a 50 ° C. atmosphere as in 4).

The reactive hot melt adhesive of the present invention can be suitably used for polyolefin-based substrates such as polyethylene films, polypropylene plates, and polypropylene films. The obtained adhesive can be used for plastic molding materials, building materials, and automobile interior parts.

Claims (4)

A polyisocyanate (A), a polyolefin polyol (B1) below, polybutadiene polyol, polyisoprene polyol, number average molecular weight of at least one selected from the group consisting of hydrogenated polybutadiene polyol and hydrogenated polyisoprene polyol 200 to 4,000 of the polyolefin polyol (B2) a urethane prepolymer obtained by reacting, as well as reactive hot-melt adhesive which is characterized by comprising the olefin resin (C).
(B1): α, β-unsaturated carboxylic acid (anhydride) is added to the double bond of the olefin resin (D) having a terminal double bond, and the imidation reaction between the introduced carbonyl group and hydroxylamine A hydroxyl group-containing polyolefin-based resin obtained by: A cured product obtained by curing the adhesive according to claim 1. Adhesive body comprising bonded in claim 1 Symbol placement of adhesive. The adhesive body according to claim 3, wherein at least one of the adherends is a polyolefin-based substrate.