JP2018111748A - Reactive hot-melt adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reactive hot-melt adhesive that has excellent heat-resistant adhesive strength, and can keep the adhesive strength even when an adhesive layer is thinned.SOLUTION: A reactive hot-melt adhesive contains a urethane prepolymer (C) obtained by the reaction of an ethylene oxide (EO)-added product (A), polymer polyol (B) and organic polyisocyanate (D), where, (A) is an EO-added product of at least one bisphenol compound selected from the group consisting of bisphenol A, bisphenol B, bisphenol E and bisphenol F, where an average mole of added EO of the product is 0.90-1.10 per hydroxy group, and a monodispersity represented by the following formula is 80% or more. Monodispersity (%)=[weight of EO-added product (A1) with 1 mol of EO added per hydroxy group/weight of EO-added product (A)]×100.SELECTED DRAWING: None

Description

  The present invention relates to a reactive hot melt adhesive.

As reactive hot melt adhesives, polyester and / or polyether polyols as polyols, and isocyanate group-terminated urethane prepolymers obtained by reacting hydroxyl groups with rosin and polyisocyanates are known.
However, when the polyether polyol is used, there is a problem that not only the initial adhesive force is not sufficient, but also the heat resistant adhesive strength (heat resistance of the cured product) is low. As a method for improving the initial adhesive force, use of a high molecular weight polyol or a high molecular weight of a urethane prepolymer can be considered, but there is a problem that the coatability is deteriorated due to an increase in melt viscosity. In order to solve this problem, a reactive hot melt adhesive made of an isocyanate group-terminated urethane prepolymer obtained by reacting an aromatic ring-containing polyether polyol and a polyisocyanate is known (for example, see Patent Document 1). . On the other hand, when a polyester-based polyol having excellent initial adhesive strength is used, there is a problem that hydrolysis resistance is poor. Further, since the adhesive strength is easily influenced by the amount (film thickness) of the reactive hot melt adhesive, there is a problem that it is necessary to increase the film thickness in order to achieve the desired adhesive strength.

JP2008-63568

The object of the present invention is to eliminate the drawbacks of the above-mentioned conventional reactive hot melt adhesives, have excellent heat resistant adhesive strength, and can maintain adhesive strength even when the thickness of the adhesive layer is reduced. Is to provide.

The inventors of the present invention have arrived at the present invention as a result of intensive studies to solve the above problems. That is, the present invention is an ethylene oxide adduct of at least one bisphenol compound selected from the group consisting of bisphenol A, bisphenol B, bisphenol E, and bisphenol F, and the average number of moles of ethylene oxide added to the adduct is a hydroxyl group. It reacts with ethylene oxide adduct (A), polymer polyol (B) and organic polyisocyanate (D) which are 0.90 to 1.10 per unit and the monodispersity represented by the following formula (1) is 80% or more. A reactive hot melt adhesive containing a urethane prepolymer (C).
Monodispersity (%) = [weight of ethylene oxide adduct (A1) having 1 mol of ethylene oxide added per hydroxyl group / weight of ethylene oxide adduct (A)] × 100 (1)

The reactive hot melt adhesive of the present invention is excellent in heat-resistant adhesive strength, and further has an effect of maintaining the adhesive strength even if the thickness of the adhesive layer is reduced.

The ethylene oxide adduct (A) in the present invention is an ethylene oxide (hereinafter referred to as EO) adduct of at least one bisphenol compound (J) selected from the group consisting of bisphenol A, bisphenol B, bisphenol E and bisphenol F. The adduct has an EO average addition mole number of 0.90 to 1.10 per hydroxyl group, preferably 0.91 to 1.09, more preferably 0.92 to 1.08.
If the EO average addition mole number of the EO adduct (A) is less than 0.90 per hydroxyl group, the adhesive strength is lowered, and if it exceeds 1.10, the heat resistant adhesive strength is lowered.
Of the bisphenol compounds (J), bisphenol A is particularly preferable.
Note that bisphenol B is 2,2-bis (p-hydroxyphenyl) butane, phenol E is 1,1-bis (p-hydroxyphenyl) ethane, and bisphenol F is bis (p-hydroxyphenyl) methane. It is.

The monodispersity of (A) represented by the above formula (1) is 80% or more, preferably 85% or more, and more preferably 90% or more.
If it is less than 80%, the adhesive strength at high temperatures is lowered.
The monodispersity and EO average addition mole number can be confirmed by gas chromatography (GC) after pretreatment with a silylating agent. The measurement conditions are as follows.

<Preparation method of sample>
A 1 g sample is taken and then 19 g acetone is added and dissolved. To this sample, 0.1 ml of TMS-H1 (Trimethylchlorosilane silylating agent, manufactured by Tokyo Chemical Industry Co., Ltd.) is added and heated to 50-70 ° C. for 2-3 minutes to complete the silylation. 1 μl of this supernatant is sampled and measured with a gas chromatograph.

<Measurement conditions for GC>
GC model: GC-14B (manufactured by Shimadzu Corporation)
Filler: Silicon GE-SE-52 (4%), carrier Cromosorb G (AW-DMC
S); 150-180 μm (packed column made by Wako Pure Chemical Industries)
Column temperature: 250-350 ° C. (temperature increase rate: 10 ° C./min)
Detector: FID
Solvent: Acetone carrier gas: Nitrogen Flow rate 50 ml / min <Calculation method of monodispersity>
It calculates by the following formula (3) from the area of each mole number of EO adducts in the gas chromatogram.
Monodispersity = 100 × 1 mol adduct area per hydroxyl group / (0-4 mol adduct area per hydroxyl group) (3)

As a method for producing the ethylene oxide adduct (A), a method using a basic catalyst having a proton affinity H of 960 to 1060 kJ / mol as a reaction for adding ethylene oxide to bisphenols (for example, JP 2008-143854 A). Can be mentioned.

  The polymer polyol (B) in the present invention refers to a polymer in which a polymer of an ethylenically unsaturated compound (b) is dispersed in a polyol (PL) having two or more hydroxyl groups, and preferably a polyol (PL). Among them, it is obtained by polymerizing an ethylenically unsaturated compound.

  Examples of the polyol (PL) in the present invention include polyether polyol (PL1), polyester polyol (PL2) and other polyols (PL3) having a number average molecular weight (hereinafter referred to as Mn) of 400 to 10,000.

  Examples of the polyether polyol (PL1) include polyalkylene glycol [polyethylene glycol, polypropylene glycol and polytetramethylene ether glycol, poly-3-methyltetramethylene ether glycol, etc.], copolymer polyoxyalkylene diol [EO / PO copolymerization]. Diol, THF / EO copolymerized diol, THF / 3-methyltetrahydrofuran copolymer diol and the like (weight ratio is, for example, 1/9 to 9/1)] and an AO adduct of a bisphenol-based compound; Examples thereof include AO adducts of trihydric or higher polyhydric alcohols [AO adducts of glycerin and AO adducts of trimethylolpropane]; and those obtained by coupling one or more of these with methylene dichloride.

  Examples of the polyester polyol (PL2) include condensed polyester polyols, polylactone polyols, castor oil-based polyols, and polycarbonate polyols.

  As the condensed polyester polyol, a low molecular weight polyol or polyether polyol (PL1) having an Mn of less than 300 and a polycarboxylic acid or an ester-forming derivative thereof (an acid anhydride and an alkyl ester having 1 to 4 carbon atoms, etc.) Examples include condensates.

  Examples of the polycarboxylic acid include dicarboxylic acids and trivalent to tetravalent or higher polycarboxylic acids, and specifically, saturated or saturated with 2 to 30 or more carbon atoms (preferably 2 to 12 carbon atoms). Unsaturated aliphatic polycarboxylic acids [C2-C15 dicarboxylic acids (shu, succinate, malon, adipine, suberin, azelain, sebatin, dodecanedicarboxylic acid, malee, fumar, itaconic acid, etc.) and C6-C20 tricarboxylic acids (Tricarbaryl and hexanetricarboxylic acid)]; aromatic polycarboxylic acid having 8 to 15 carbon atoms [dicarboxylic acid such as terephthal, isophthal and phthalic acid, and tri or tetracarboxylic acid such as trimellit and pyromellitic acid]; carbon A alicyclic polycarboxylic acid of 6 to 40 (eg, dimer acid); and a sulfo group-containing polycarboxylic acid Those obtained by introducing a sulfo group into the polycarboxylic acid, such as sulfosuccinic acid, sulfomalon, sulfoglutar, sulfoadipine and sulfoisophthalic acid and their salts (for example, metal salts, ammonium salts, amine salts and quaternary ammonium salts); and Examples include carboxy-terminated polymers.

  As the carboxy-terminated polymer, a polyether polycarboxylic acid [for example, a low molecular weight polyol having an Mn of less than 300 or a carboxymethyl ether of a polyol such as a polyether polyol (d1) (obtained by reacting monochloroacetic acid in the presence of alkali) Polyamides and / or polyester polycarboxylic acids (for example, lactams having 4 to 15 carbon atoms (such as caprolactam, enantolactam, laurolactam, undecanolactam, etc.) or carbon atoms having 4 to 15 carbon atoms using the polycarboxylic acid as an initiator. Polylactam polycarboxylic acid and polylactone polycarboxylic acid obtained by ring-opening polymerization of lactones (γ-butyrolactone, γ-valerolactone, ε-caprolactone, etc.).

  Examples of polylactone polyols include ring-opened adducts of lactones having 4 to 15 carbon atoms (γ-butyrolactone, γ-valerolactone, ε-caprolactone, etc.), which are initiated by water or a low molecular weight polyol having an Mn of less than 300. Can be mentioned.

  Castor oil-based polyols include castor oil (ricinoleic acid triglyceride), partially dehydrated castor oil, partially acylated castor oil, hydrogenated castor oil, and modified products thereof [polyether polyol (PL1) or low molecular weight Mn of less than 300 Ester polyol obtained by transesterification reaction between polyol and castor oil, partially dehydrated castor oil or hydrogenated castor oil, polyether polyol (PL1) or low molecular polyol having Mn of less than 300 and castor oil fatty acid or hydrogenated castor oil Ester obtained by esterification reaction with fatty acid, etc.].

  Polycarbonate polyols include ring-opening addition / polycondensation products of alkylene carbonates whose initiator is a low molecular weight polyol having an Mn of less than 300, and polycondensation (transesterification) of a low molecular weight polyol having an Mn of less than 300 and diphenyl or dialkyl carbonate. Thing etc. are mentioned.

  Examples of other polyols (PL3) include polyolefin polyols, polyalkadiene polyols, and acrylic polyols.

  Examples of the polyolefin polyol include polyisobutene polyol.

  Examples of the polyalkadiene polyol include polyisoprene polyol, polybutadiene polyol, hydrogenated polyisoprene polyol, and hydrogenated polybutadiene polyol.

Examples of the acrylic polyol include a copolymer of an alkyl (meth) acrylate (alkyl 1 to 30 carbon atoms) ester [butyl (meth) acrylate and the like] and a hydroxyl group-containing acrylic monomer [hydroxyethyl (meth) acrylate and the like]. Can be mentioned.

In the above and the following, Mn means the number average molecular weight measured by gel permeation chromatography.

  Of these polyols, polyether polyols are preferred from the viewpoint of viscosity.

The ethylenically unsaturated compound (b) in the present invention is, for example, styrene, alkyl methacrylate, acrylonitrile, or the like, and two or more of these compounds. Among these, styrene, acrylonitrile, and a mixture of styrene and acrylonitrile are preferable.

As a method for producing the polymer polyol (B), a method in which a polymer is synthesized by polymerizing monomers in a polyol in the presence or absence of a dispersant, or a solution in which a synthetic polymer is dissolved in a solvent is used. In addition to the polyol, there may be mentioned a method of removing the solvent if necessary. In addition, a polymer composition or a mixture obtained by polymerizing an ethylenically unsaturated compound in a polyol is generally called a polymer polyol and is commercially available, and this commercially available polymer polyol can be used as the polyol (B) as it is. it can.

Examples of the polymer polyol include those obtained by polymerizing an ethylenically unsaturated compound in the polyol (PL). Ethylenically unsaturated compounds include acrylic monomers having 3 to 30 carbon atoms, such as (meth) acrylonitrile and alkyl (1 to 20 or more carbon atoms), (meth) acrylates (such as methyl methacrylate); hydrocarbon monomers such as Aromatic unsaturated hydrocarbons (8 to 20 carbon atoms, such as styrene) and aliphatic unsaturated hydrocarbons [alkenes having 2 to 20 or more carbon atoms, alkadienes, such as α-olefins (hexene, octene, etc.) and butadiene And combinations of two or more of these (for example, a combination of acrylonitrile / styrene). The amount of the polymer (b1) of the ethylenically unsaturated compound (b) in the polymer polyol (B) is preferably 10 to 80%, more preferably 20 to 70%, particularly preferably from the viewpoint of heat resistance and viscosity. 25-60%.

<Content of polymer (b1) of ethylenically unsaturated compound (b)>
In a 50 ml centrifuge tube for centrifugation, about 5 g of polymer polyol is precisely weighed to obtain the polymer polyol weight (W1). Add 50 g of methanol to dilute. Using a cooling centrifuge [model number: H-9R, manufactured by Kokusan Co., Ltd.], centrifuge at 18,000 rpm for 60 minutes at 20 ° C. The supernatant is removed using a glass pipette. The operation of adding 50 g of methanol to the residual sediment, diluting, and centrifuging in the same manner as above to remove the supernatant is repeated three more times. The residual sediment in the centrifuge tube is dried under reduced pressure at 3 to 4 kPa at 80 ° C. for 3 hours. The dried sediment is weighed, and the weight is defined as (W2). The value calculated by the following formula is the polymer content (% by weight) of the ethylenically unsaturated compound.
Polymer content (% by weight) = (W2) × 100 / (W1)

The content of the ethylene oxide adduct (A) based on the total weight of the ethylene oxide adduct (A) and the polymer polyol (B) is preferably 10 to 25 wt%, more preferably 15 to 25 wt%, ) Is preferably 75 to 90% by weight, more preferably 75 to 85% by weight.

Examples of the organic polyisocyanate component (D) in the present invention include organic polyisocyanate (d1) having two or more isocyanate groups in one molecule. An organic polyisocyanate component (D) may be used individually by 1 type, or may use 2 or more types together.

As the organic polyisocyanate (d1), those conventionally used in the production of polyurethane can be used. For example, a chain aliphatic polyisocyanate (d11) having 4 to 22 carbon atoms and an alicyclic polyisocyanate having 8 to 18 carbon atoms. Examples thereof include isocyanate (d12), aromatic polyisocyanate (d13) having 8 to 26 carbon atoms, araliphatic polyisocyanate (d14) having 10 to 18 carbon atoms and a modified product (d15) of these polyisocyanates.
Examples of the chain aliphatic polyisocyanate having 4 to 22 carbon atoms (d11) include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (hereinafter abbreviated as HDI), dodecamethylene diisocyanate, and 1,6,11-undecane triisocyanate. 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate and 2-isocyanato Examples include ethyl-2,6-diisocyanatohexanoate.

  Examples of the alicyclic polyisocyanate having 8 to 18 carbon atoms (d12) include, for example, isophorone diisocyanate (hereinafter abbreviated as IPDI), 4,4-dicyclohexylmethane diisocyanate (hereinafter abbreviated as hydrogenated MDI), cyclohexylene diisocyanate, and methyl. Examples include cyclohexylene diisocyanate, bis (2-isocyanatoethyl) -4-cyclohexene-1,2-dicarboxylate and 2,5- or 2,6-norbornane diisocyanate.

Examples of the aromatic polyisocyanate having 8 to 26 carbon atoms (d13) include 1,3- or 1,4-phenylene diisocyanate, 2,4- or 2,6-tolylene diisocyanate (hereinafter abbreviated as TDI), and crude TDI. 2,2′-, 2,4′- or 4,4′-diphenylmethane diisocyanate (hereinafter abbreviated as MDI), crude MDI, polyarylpolyisocyanate, 4,4′-diisocyanatobiphenyl, 3,3 ′ -Dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatodiphenylmethane, 1,5-naphthylene diisocyanate, 4,4 ', 4 "-triphenylmethanetri Examples include isocyanate and m- or p-isocyanatophenylsulfonyl isocyanate.
Examples of the C10-18 araliphatic polyisocyanate (d14) include m- or p-xylylene diisocyanate and α, α, α ′, α′-tetramethylxylylene diisocyanate.

  As the modified polyisocyanate (d15) of (d11) to (d14), the modified polyisocyanate (urethane group, carbodiimide group, allophanate group, urea group, biuret group, uretdione group, uretoimine group, isocyanurate group) Or oxazolidone group-containing modified products), for example, modified MDI (urethane-modified MDI, carbodiimide-modified MDI, trihydrocarbyl phosphate-modified MDI, etc.), urethane-modified TDI, biuret-modified HDI, isocyanurate-modified HDI, and isocyanurate-modified IPDI. Modified products of

  Of the organic polyisocyanates (d1), aromatic polyisocyanates and modified products thereof are preferable from the viewpoint of reactivity, and 4,4′-, 2,4′- or 2,2′-diphenylmethane diisocyanate and more preferable. These denatured bodies.

  The reactive hot melt adhesive of the present invention comprises an NCO-terminated urethane prepolymer (C) obtained by reacting an excess of the above polyisocyanate (D) with an ethylene oxide adduct (A) and a polymer polyol (B). Become. The reaction is usually performed at an equivalent ratio (isocyanate group / hydroxyl group) = 1.01 / 1 to 5/1, more preferably 1.2 / 1 to 4/1, particularly preferably 1.5 / 1 to 3/1. is there.

  Although it does not specifically limit as a manufacturing method of NCO terminal urethane prepolymer (C), The well-known method of making organic polyisocyanate and a polyol react in nitrogen atmosphere is mentioned.

The reaction temperature in the prepolymerization reaction is usually 30 to 140 ° C., preferably 50 to 120 ° C. from the viewpoint of reactivity and the prevention of side reactions. In addition, the reaction is usually carried out in the absence of a solvent, but if necessary, an inert solvent having no reactivity with isocyanate groups [for example, aromatic hydrocarbons (toluene, xylene, etc.), ketones (methyl ethyl ketone, methyl isobutyl ketone, etc.) And a mixture of two or more thereof], and these solvents may be removed later by distillation.

In the urethanization reaction, a urethanization catalyst may be used, and various urethanization catalysts can be used. For example, a metal catalyst [tin catalyst [trimethyltin laurate, trimethyltin hydroxide, dimethyltin dilaurate, dibutyl Tin diacetate, dibutyltin dilaurate, stannous octoate, dibutyltin maleate, etc.], lead catalysts [lead oleate, lead 2-ethylhexanoate, lead naphthenate, lead octenoate, etc.], other metal catalysts [naphthenic acid Metal salt (such as cobalt naphthenate), phenylmercury propionate, etc.]]; amine catalyst {triethylenediamine, tetramethylethylenediamine, diazabicycloalkene [1,8-diazabicyclo [5,4,0] undecene-7 [ DBU (manufactured by San Apro, registered trademark)] Dialkyl (C1-3) aminoalkyl (C2-4) amine [dimethylaminoethylamine, dimethylaminopropylamine, diethylaminopropylamine, dipropylaminopropylamine, etc.], heterocyclic aminoalkyl (C2-6) amine [2- (1-aziridinyl) ethylamine, 4- (1-piperidinyl) -2-hexylamine and the like], and carbonates and organic acids (C1-3, such as formic acid) salts thereof; N-methyl and -ethylmorpholine, triethylamine , Dimethyl- and diethylethanolamine, etc.}; and combinations of two or more of these.

The use amount of the urethanization catalyst is preferably 0.5% or less based on the total weight of (A), (B) and (D), more preferably 0 from the viewpoints of reactivity and thermal stability of the adhesive. 0.0001 to 0.1%, more preferably 0.0005 to 0.05%, particularly preferably 0.001 to 0.01%.
As a reaction method, for example, (A), (B), (D) and a urethanization catalyst are charged into a reaction vessel having a temperature control function, and the temperature is usually 30 to 160 (preferably 50 to 140) ° C., and the time is Usually, a method of reacting for 30 to 1,000 (preferably 60 to 300) minutes, or (A), (B), (D) and a urethanization catalyst are uniformly mixed, and then the mixture is poured into, for example, a twin screw extruder. Usually, the method of making it react continuously at 80-250 (preferably 100-220) degreeC etc. are mentioned.
The content (% by weight) of NCO groups in the obtained urethane prepolymer (C) is preferably 0.2 to 10%, more preferably 0, from the viewpoints of heat resistance after curing and thermal stability during heat melting. .5-7%.

The hot melt adhesive of the present invention can optionally contain other additives (E) for resins within a range that does not impair the effects of the present invention, according to various purposes and applications.

Examples of the additive (E) include tackifiers, antioxidants, ultraviolet absorbers, light stabilizers, plasticizers, adsorbents, colorants, fillers, nucleating agents, lubricants, mold release agents, flame retardants, and the like. There may be mentioned at least one additive selected from the group consisting of fragrances.

Examples of the tackifier include terpene resin, terpene phenol resin, phenol resin, aromatic hydrocarbon modified terpene resin, rosin resin, modified rosin resin, synthetic petroleum resin (aliphatic, aromatic or alicyclic synthetic petroleum resin, etc. ), Coumarone-indene resin, xylene resin, styrene resin, dicyclopentadiene resin, and hydrogenated products of these having hydrogenated unsaturated double bonds.

Antioxidants include hindered phenol compounds [pentaerystyl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-t. -Butyl-4-hydroxyphenyl) propionate, etc.], phosphorus compound [tris (2,4-di-t-butylphenyl) phosphite, etc.], sulfur compound [pentaerystyl-tetrakis (3-laurylthiopropionate) , Dilauryl-3,3′-thiodipropionate, etc.].

Examples of the ultraviolet absorber include benzotriazole compounds [2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, etc.]. It is done.

Examples of the light stabilizer include hindered amine compounds [(bis-2,2,6,6-tetramethyl-4-piperidyl) sebacate and the like] and the like.

As the plasticizer, various plasticizers [for example, adhesive technology Vol. 20, (2), 21 (2000), etc.], process oil (paraffin, naphthene or aromatic compound type); liquid resin (Mn 300 to 6,000, for example, liquid polybutene, liquid polybutadiene, liquid Polyisoprene); hydrogenated product of the liquid resin; low molecular weight (Mn 300 to 10,000) polyisobutylene; and mixtures of two or more thereof.

Examples of the adsorbent include alumina, silica gel, molecular sieve and the like.

Examples of the colorant include pigments (titanium oxide, carbon black, etc.), dyes (azo, anthraquinone, indigoid, alizarin, acridine, nitroso, aniline dyes, etc.) and the like.

Examples of the filler include talc, mica, calcium carbonate and the like.

Examples of the nucleating agent include sorbitol, phosphate metal salt, benzoic acid metal salt, and phosphate metal salt.

Examples of the lubricant include calcium stearate, butyl stearate, oleic amide and the like.

Examples of the release agent include carboxyl-modified silicone oil and hydroxyl-modified silicone oil.

  Examples of the flame retardant include a halogen-containing flame retardant, a phosphorus-containing flame retardant, an antimony-containing flame retardant, and a metal hydroxide-containing flame retardant.

Examples of the fragrances include diterpenes and limonene.

The total content of the additive (E) is usually 40% by weight or less based on the total weight of the reactive hot melt adhesive, preferably 0.002 to 30% by weight, more preferably from the viewpoint of the addition effect and adhesiveness. Is 0.1 to 10% by weight.

  The ring and ball softening point of the reactive hot melt adhesive of the present invention is preferably 20 to 120 ° C., more preferably 30 to 110 ° C. from the viewpoint of initial cohesive force and melt viscosity; From the viewpoint of cohesive strength and coatability, it is preferably 500 to 200,000 mPa · s, and more preferably 1,000 to 100,000 mPa · s.

Moreover, as a production facility for the reactive hot melt adhesive, it is only necessary that the components of the adhesive can be heated, melted and kneaded, and a normal hot melt production facility can be used.
Examples include a mixer having a highly compressible screw or ribbon stirrer, a reaction mixing tank, a single or twin screw extruder, a sigma blade mixer, a ribbon blender, a butterfly mixer, and a kneader.
The mixing temperature is preferably 60 to 250 ° C. from the viewpoints of mixing properties and thermal deterioration, and is preferably performed in an inert gas atmosphere such as nitrogen gas in order to prevent crosslinking of the reactive hot melt adhesive.

The reactive hot melt adhesive of the present invention is formed into a desired shape such as a block, a sheet or a film, if necessary. An extruder or the like is used for molding.
The method for using the reactive hot melt adhesive of the present invention is not particularly limited. For example, when the adhesive is in a block shape, the adhesive is melted and then adhered to the adherend to be bonded. Used by applying.

The applicator includes an ordinary applicator for hot melt adhesive, [roll coater (heater capable of heating, gravure roll, reverse roll, etc.), curtain coater, bead, spiral, spray, slot, etc.] and extruder [ Single screw and twin screw extruders, kneader ruder, etc.].
In the case of an applicator, an adhesive can be applied to one or both of the adherends and bonded together before cooling and solidification, or after cooling and solidification, the adherends can be combined, heated and bonded again. When bonding, it is better to pressurize and release the pressure after cooling and solidification.
In the case of an extruder, extrusion is performed on one or both of the adherends, and after cooling and solidification, the adherends are combined, heated again, and bonded. When bonding, it is better to pressurize and release the pressure after cooling and solidification. Moreover, it can coextrude between adherends and can perform bonding simultaneously.
When applied to the adherend, the melting temperature of the adhesive is usually 80 to 160 ° C., preferably 100 to 140 ° C. from the viewpoint of adhesion and thermal stability, and the melt viscosity at the coating temperature is usually 1 to 100 Pa · From the viewpoint of s and adhesiveness, it is preferably 2 to 50 Pa · s.

When the adhesive is a sheet or a film, the adhesive is sandwiched between adherends to be bonded together and bonded by heating and melting, or placed on one or both adherends and heated. It is melted and bonded 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 10 to 20 ° C. higher than the melting point (or softening point) from the viewpoint of adhesiveness. Moreover, it is better to pressurize when bonding, and the pressure is 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 15 MPa from the viewpoint of adhesiveness and moldability.
Although there is no restriction | limiting in particular in the thickness of a sheet | seat or a film, Preferably it is 10-500 micrometers from a viewpoint of adhesiveness and a moldability, 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 NCO group contained and moisture in the air. The curing temperature is usually 5 ° C. or higher, and preferably 10 to 100 ° C. from the viewpoint of reactivity and side reaction suppression. The humidity condition is preferably 20% RH or more, more preferably 30 RH or more, from the viewpoint of reactivity. The curing time is usually several minutes to 200 hours, preferably 1 to 72 hours from the viewpoint of reactivity and workability. The cured product thus obtained has good cured properties and excellent durability such as heat resistance and solvent resistance.

  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.

Production Example 1
[Synthesis of bisphenol A EO adduct (A-1)]
A glass autoclave was charged with 137.0 g of toluene (40% based on bisphenols) and 342.4 g (1.50 mol) of bisphenol A. After nitrogen substitution, the temperature was raised to 75 ° C., and bisphenol A was converted to toluene. Dispersed. To this, 2.73 g of a 25% aqueous solution of tetramethylammonium hydroxide (proton affinity: 1040 kJ / mol) was added.
Nitrogen substitution was performed again, and EO was dropped and reacted in a range of 75 to 95 ° C. and a reaction pressure of 0.2 MPa or less. During the reaction, sampling was performed as appropriate, and the addition mole distribution of the reaction product to bisphenol was traced by GC, and the reaction was terminated when the 1 mol addition product was 0.1% or less. The required EO was 139.9 g (3.18 mol), and the reaction time was 7 hours.
After the reaction, unreacted EO, catalyst, solvent and the like were distilled off at 130 to 160 ° C. under reduced pressure to obtain an EO product (A-1) of bisphenol A of the present invention.
When this (A-1) was analyzed by GC, the EO average added mole number per hydroxyl group of the obtained (A-1) was 1.02, and the monodispersity was 97.4%.

Production Example 2
[Synthesis of bisphenol A EO adduct (A-2)]
In a glass autoclave, 85.6 g (25% by weight based on bisphenols) of (A-1) obtained in Example 1 was melted and added as a solvent for the reaction system. After heating up to 110 ° C. and melting it, 342.4 g (1.50 mol) of bisphenol A was charged and purged with nitrogen, and then cooled to 95 ° C. to disperse bisphenol A. To this was added 0.30 g of sodium hydroxide (proton affinity: 1071.8 kJ / mol).
Nitrogen substitution was performed again, and EO was dropped and reacted in a range of 75 to 95 ° C. and a reaction pressure of 0.2 MPa or less. During the reaction, sampling was performed as appropriate, and the distribution of addition moles of the reaction product to bisphenol was monitored by GC. The reaction was terminated when the 1 mol adduct was 0.1% or less. The required EO was 150.5 g (3.42 mol), and the reaction time was 7 hours.
After the reaction, the catalyst was neutralized with phosphoric acid, and unreacted EO was distilled off under reduced pressure at 130 to 160 ° C. to obtain an EO adduct (A-2) of bisphenol A.
When this (A-2) was analyzed by GC, the EO average added mole number per hydroxyl group of the obtained (A-2) was 1.09, and the monodispersity was 82.5%.

Production Example 3
[Synthesis of bisphenol A EO adduct (A-3)]
The amount of EO dropped in Production Example 2 was set to 154.0 g (3.50 mol), and the reaction was terminated when 1 mol of adduct became 0.1% or less. Reacted.
After the reaction, the catalyst was neutralized with phosphoric acid, and unreacted EO was distilled off under reduced pressure at 130 to 160 ° C. to obtain EO (A-3) of bisphenol A.
When this (A-3) was analyzed by GC, the EO average added mole number per hydroxyl group of the obtained (A-3) was 1.10, and the monodispersity was 81.3%.

Production Example 4
[Synthesis of bisphenol A EO adduct (A-4)]
In the same manner as in Production Example 1, except that the amount of EO reacted dropwise in Production Example 1 was 124.8 g (2.84 mol) and the reaction was terminated when 1 mol adduct was 0.1% or less. Reacted.
After the reaction, the catalyst was neutralized with phosphoric acid, and unreacted EO was distilled off under reduced pressure at 130 to 160 ° C. to obtain EO (A-4) of bisphenol A.
When this (A-4) was analyzed by GC, the EO average added mole number per hydroxyl group of the obtained (A-4) was 0.91, and the monodispersity was 88.3%.

Comparative Production Example 5
[Synthesis of bisphenol A EO adduct (A′-1)]
The reaction was conducted in the same manner as in Production Example 2 except that the amount of sodium hydroxide (proton affinity: 1071.8 kJ / mol) used in Production Example 2 was changed to 0.24 g.
The reaction was terminated when 1 mol adduct was 0.1% or less, and EO required was 121.8 g (2.77 mol), and the reaction time was 7 hours.
After the reaction, the catalyst was neutralized with phosphoric acid, and unreacted EO was distilled off at 130 to 160 ° C. under reduced pressure to obtain EO (A′-1) of normal purity bisphenol A.
When this (A′-1) was analyzed by GC, the average added mole number of EO per hydroxyl group of the obtained (A′-1) was 0.89, and the monodispersity was 80.3%. It was.

Comparative Production Example 6
[Synthesis of bisphenol A EO adduct (A′-2)]
The amount of EO dropped in Production Example 2 was 157.5 g (3.58 mol), and the reaction was terminated when 1 mol adduct became 0.1% or less. Reacted.
After the reaction, the catalyst was neutralized with phosphoric acid, and unreacted EO was distilled off at 130 to 160 ° C. under reduced pressure to obtain EO (A′-2) of normal purity bisphenol A.
When this (A′-2) was analyzed by GC, the average added mole number of EO per hydroxyl group of the obtained (A′-2) was 1.12, and the monodispersity was 80.1%. It was.

Comparative Production Example 7
[Synthesis of bisphenol A EO adduct (A′-3)]
The reaction was carried out in the same manner as in Production Example 2 except that sodium hydroxide used in Production Example 2 was replaced with 0.22 g of a 40% aqueous solution of trimethylamine (proton affinity: 948.9 kJ / mol).
Even after 15 hours from the reaction, the 1 mol adduct was 13%, and it was expected that it would take a considerable amount of time to reach 0.1% or less. EO dripped by this stage was 132 g (3.00 mol).
After the reaction, the catalyst was neutralized with phosphoric acid, and unreacted EO was distilled off under reduced pressure at 130 to 160 ° C. to obtain EO (A′-3) of bisphenol A.
When this (A′-3) was analyzed by GC, the average added mole number of EO per hydroxyl group of the obtained (A′-3) was 0.98, and the monodispersity was 78.9%. It was.

The composition of the raw material used for the polymer polyol (B) described in Table 1 is as follows.
Polyol (PL1-1): “SANNICS GP-3030” manufactured by Sanyo Chemical Industries
Polyol (PL1-2): “Polyol 50” manufactured by Sanyo Chemical Industries
Polyol (PL1-3): “SANNICS FA-703” manufactured by Sanyo Chemical Industries
Polyol (PL1-4): A polyol having a number average molecular weight of 4500 added to glycerin in the order of PO-EO.
Polyol (PL1-5): A polyol having a number average molecular weight of 530 obtained by adding PO to bisphenol A.
Radical polymerization initiator (e-1): “V-59” manufactured by Wako Pure Chemical Industries, Ltd.
Dispersant (f-1): Dispersant having a hydroxyl value of 26 obtained by jointing 1 mol of polyol (PL1-2) and 0.2 mol of 2-hydroxymethacrylate with 0.4 mol of TDI.

Production Example 8
[Synthesis of Polymer Polyol Intermediate (IB1-1)]
A four-necked flask equipped with a temperature controller, a vacuum stirring blade, a dropping pump, a pressure reducing device, a Dimroth condenser, a nitrogen inlet and an outlet, 310 g of polyol (PL1-4), 50 g of dispersant (f-1) and 60 g of xylene And heated to 130 ° C. with stirring. Then, 192 g of polyol (PL1-4), 16 g of dispersant (f-1), 154 g of styrene, 154 g of acrylonitrile, 3 g of radical polymerization initiator (e-1) and 61 g of xylene were mixed with a dropping pump. The resulting solution was continuously added dropwise at a rate of 25 g / min, and after completion of the addition, polymerization was further performed at 130 ° C. for 30 minutes. Thereafter, the mixture was cooled to 25 ° C. to obtain a polymer polyol intermediate (IB1-1). The polymer (b1) content of the ethylenically unsaturated compound (b) was 30 (% by weight).

Production Example 9
[Synthesis of Polymer Polyol Intermediate (IB2-1)]
In a four-necked flask equipped with a temperature controller, a vacuum stirring blade, a dripping pump, a decompression device, a Dimroth condenser, a nitrogen inlet and an outlet, polyol (PL1-1) 255 g, (PL1-5) 40 g, dispersant ( f-1) 57 g and 124 g of xylene were added, and the temperature was raised to 130 ° C. with stirring. Next, 142 g of polyol (PL1-1), 18 g of dispersant (f-1), 105 g of acrylonitrile, 245 g of styrene, 0.4 g of divinylbenzene, 3.6 g of radical polymerization initiator (e-1) and 10 g of xylene are shown in Table 1. The monomer-containing mixed solution was continuously dropped at a rate of 25 g / min using a dropping pump, and after completion of the dropping, polymerization was further performed at 130 ° C. for 30 minutes. Thereafter, the mixture was cooled to 25 ° C. to obtain a polymer polyol intermediate (IB2-1). The polymer (b1) content of the ethylenically unsaturated compound (b) was 33 (% by weight).

Production Example 10
[Production of polymer polyol (B-1)]
[First step] Two tanks of a continuous polymerization apparatus (SUS pressure-resistant reaction vessel connected with a liquid feed line and an overflow line) are prepared, and the first overflow line is connected to the inlet of the second polymerization tank in series. Deploy. Each of the first and second polymerization tanks was charged with 2,000 g of an initial charge liquid in which 900 g of polyol (PL1-3), 900 g of polyol (PL1-4) and 200 g of xylene were mixed, and the temperature was increased to 130 ° C. Warm up. Polymer polyol intermediate (IB1-1) 125 g, polyol (PL1-3) 167 g, polyol (PL1-4) 163 g, dispersant (f-1) 38 g, acrylonitrile 78 g, styrene 78 g, radical polymerization initiator (e-1 ) After line blending 1.6 g and 50 g of xylene using a static mixer, the raw material mixture was continuously fed to the first polymerization tank at a liquid feed speed of 113 g / min, and overflowed from the polymerization tank. A polymer polyol intermediate (IB1-2) was obtained. Overflowing from the first polymerization tank (IB1-2) was continuously fed to the second polymerization tank at the first tank feeding speed.
[Second Step] From the first tank, overflowed at a liquid feed rate of 113 g / min (IB1-2), 70 g of polyol (PL1-3), 16 g of polyol (PL1-4), 89 g of acrylonitrile, 89 g of styrene, radical polymerization A raw material mixture obtained by mixing 1.9 g of initiator (e-1) and 5 g of xylene is line-blended using a static mixer, and then continuously fed to the second polymerization tank at a feed rate of 97 g / min. The reaction liquid fed and overflowed from the polymerization tank was stocked in a SUS receiving tank to obtain a polymer polyol intermediate (IB1-3). (IB1-3) was added with unreacted monomer and xylene while adding pervaporated water (amount of water contained in the steam was 4% by weight with respect to the polymer polyol over 2 hours) from another port. , 666-3,999 Pa (20-30 torr) for 2 hours at 130-140 ° C. under reduced pressure to obtain a polymer polyol intermediate (IB1-3). The obtained polymer polyol intermediate (IB1-3) was mixed with 42 g of polyol (PL1-3) and 42 g of polyol (PL1-4) to obtain polymer polyol (B-1). The polymer (b1) content of the ethylenically unsaturated compound (b) was 40 (% by weight).

Production Example 11
[Production of polymer polyol (B-2)]
[First step] Two tanks of a continuous polymerization apparatus (SUS pressure-resistant reaction vessel connected with a liquid feed line and an overflow line) are prepared, and the first overflow line is connected to the inlet of the second polymerization tank in series. Deploy. Each of the first and second polymerization tanks was charged with 2,000 g of an initial charge liquid prepared by previously mixing 1800 g of polyol (PL1-1) and 200 g of xylene, and the temperature was raised to 130 ° C. Polymer polyol intermediate (IB2-1) 125g, polyol (PL1-1) 210g, (PL1-5) 6g, dispersant (f-1) 28g, acrylonitrile 36g, styrene 84g, divinylbenzene 1.2g, radical polymerization started After line blending the raw material mixed liquid obtained by mixing 1.2 g of the agent (e-1) and 38 g of xylene using a static mixer, the liquid is continuously fed to the first polymerization tank at a liquid feeding speed of 113 g / min. The polymer polyol intermediate (IB2-1) was obtained by overflowing from the polymerization tank. (IB2-1) overflowed from the first polymerization tank was continuously fed to the second polymerization tank at the first liquid feed speed.
[Second step] (IB2-1) and (PL1-1) 113 g, acrylonitrile 84 g, styrene 196 g, radical polymerization initiator (e-1) overflowed from the first tank at a liquid feed rate of 113 g / min. A raw material mixture containing 8 g and 9 g of xylene is line-blended using a static mixer, then continuously fed to the second polymerization tank at a feed speed of 97 g / min, and overflowed from the polymerization tank. The reaction solution was stocked in a SUS receiving tank to obtain a polymer polyol intermediate (IB2-2). (IB2-2) was added with super-steam (the amount of water contained in the steam was 4% by weight with respect to the polymer polyol over a period of 2 hours) from another port while adding unreacted monomer and xylene. , 666-3,999 Pa (20-30 torr) for 2 hours at 130-140 ° C. under reduced pressure to obtain a polymer polyol intermediate (IB2-3). The obtained polymer polyol intermediate (IB2-3) was mixed with 113 g of polyol (PL1-1) to obtain a polymer polyol (B-2). The polymer (b1) content of the ethylenically unsaturated compound (b) was 45 (% by weight).

The following was used for (B ′) and (D) described in Table 1.
Polypropylene glycol (B′-1): Sanyo Chemical Industries “Sanix GP-3000” polyester polyol (B′-2): Sanyo Chemical Industries “San Ester 4620”
4,4′-diphenylmethane diisocyanate (D): “Millionate MT” manufactured by Tosoh Corporation

Examples 1-7, Comparative Examples 1-5
[Hot melt adhesive (H)]
Into a flask equipped with a stirrer, a condenser, and a thermometer, the ethylene oxide adduct (A) and polymer polyol (B) in the number of blended parts shown in Table 1 were charged all at once, and uniformly dissolved at 120 ° C. and then dehydrated under reduced pressure. (120 ° C., 133 Pa, 1 hour). After cooling to 60 ° C., a mixture of organic polyisocyanates (D) shown in Table 1 under a nitrogen stream was charged, stirred and mixed, reacted at 80 ° C. for 3 hours, and then the desired reactive hot melt adhesive ( H-1) to (H-7) and comparative reactive hot melt adhesives (H′-1) to (H′-5) were obtained.

  About the obtained reactive hot-melt-adhesive, the adhesive strength, heat-resistant creep property, and immersion peelability were evaluated by the following test methods. The results are shown in Table 1.

(1) Adhesive strength Reactive hot melt adhesive was pressed with a press machine temperature controlled at 120 ° C. (10 MPa, 30 seconds) sandwiched between an olefin decorative sheet and a release film so as to have a film thickness of 50 μm. ). After peeling off the release film, the olefin decorative sheet coated with the reactive hot melt adhesive is allowed to stand for about 10 seconds on a press machine adjusted to 120 ° C. for reactive hot melt adhesion on the olefin sheet. After confirming that the agent was melted, the surfaces of MDF (Medium Density Fiber Boat) were combined, and then a 2 kg load rubber roller was used to make one reciprocation at a speed of 300 mm / min, and the test piece was prepared. . The olefin sheet was cut into an adhesive width of 25 mm, and the adhesive strength after 10 minutes was measured (180 ° peeling, using a digital force gauge). This maximum value was defined as the adhesive strength (unit: N / 25 mm). Similarly, when the film thickness of the reactive hot melt adhesive is 25 μm, measurement is performed, and the reduction rate (%) is calculated in comparison with the adhesive strength of the film thickness of 50 μm.
Reduction rate (%) = [Adhesive strength (film thickness 50 μm) −Adhesive strength (film thickness 25 μm)] / Adhesive strength (film thickness 50 μm) × 100

(2) Heat-resistant creep resistance The reactive hot melt adhesive was pressed with a press adjusted to a temperature of 120 ° C. between a olefin decorative sheet and a release film so as to have a film thickness of 50 μm (10 MPa, 30 Seconds). After peeling off the release film, the olefin decorative sheet coated with the reactive hot melt adhesive is allowed to stand for about 10 seconds on a press machine adjusted to 120 ° C. for reactive hot melt adhesion on the olefin sheet. After confirming that the agent was melted, the surfaces of MDF (Medium Density Fiber Boat) were combined, and then a 2 kg load rubber roller was used to make one reciprocation at a speed of 300 mm / min, and the test piece was prepared. . The test piece was cured for 24 hours in an atmosphere of 23 ° C. and 50% RH to obtain a test piece for heat resistance creep resistance evaluation.
The test piece was horizontally bridged on two struts having a distance of about 13 cm between the struts (each about 20 cm in height and 3 cm in width) with the polyolefin decorative sheet bonded side down.
Next, about 2 cm was peeled off from one end of the olefin-made decorative sheet, a marked line was drawn on the sheet at that position, a 500 g weight was attached to the peeled sheet end, and the sheet was suspended in the vertical direction.
This was left still in a 60 degreeC thermostat for 24 hours, and 90 degree heat resistant creep (deviation distance from a marked line, unit: mm) was measured.

(3) Immersion peelability (based on JAS Type 1)
The reactive hot melt adhesive was pressed between a olefin decorative sheet and a release film on a press machine adjusted to a temperature of 120 ° C. so as to have a film thickness of 50 μm (10 MPa, 30 seconds). After peeling off the release film, the olefin decorative sheet coated with the reactive hot melt adhesive is allowed to stand for about 10 seconds on a press machine adjusted to 120 ° C. for reactive hot melt adhesion on the olefin sheet. After confirming that the agent was melted, match the surface of MDF (medium density fiber boat) cut to a size of 75 mm x 75 mm, and then paste it by reciprocating once at a speed of 300 mm / min using a 2 kg load rubber roller. A test piece was prepared. The test piece was cured for 24 hours in an atmosphere of 23 ° C. and 50% RH, and used as a test piece for an immersion peel test (JAS type 1). After curing, the test piece was immersed in warm water of 100 ± 3 ° C. for 4 hours, and then placed in a 60 ± 3 ° C. smooth air dryer and dried for 20 hours. Then, after being immersed in warm water of 100 ± 3 ° C. for 4 hours, it was dried for 3 hours with a 60 ± 3 ° C. normal air dryer, and the appearance was confirmed.
<Evaluation criteria>
A: No peeling in the adhesive layer of the test piece. (Peeling length: 0 mm)
◯: The length of the part of the test piece that does not peel off is 2/3 or more on each side surface. (Peeling length: less than 25 mm)
(Triangle | delta): The length of the part which does not peel in the contact bonding layer of a test piece is less than 2/3-1/3 or more in each side surface. (Peeling length: 25 mm to less than 50 mm)
X: The length of the part which does not peel in the contact bonding layer of a test piece is less than 1/3 in each side surface. (Peeling length: 50mm or more)

When Examples 1-7 are compared with Comparative Examples 1-5, the Examples are superior to Comparative Examples in heat-resistant adhesive strength (heat-resistant creep resistance and immersion peelability), and even if the thickness of the adhesive layer is reduced. It turned out that it is excellent in the effect which can hold | maintain adhesive strength (the reduction rate of adhesive strength is small).

The reactive hot melt adhesive of the present invention is useful for the following uses.
(1) Building material applications: Adhesives for woody materials (plywood, particle board, hardboard, laminated wood, etc.) and other building materials (concrete, mortar, wallpaper, floor materials, tiles, etc.).
(2) Fiber material use: Adhesive for fiber material (nonwoven fabric, woven fabric, carpet, etc.).
(3) Other materials: Plastic (hard and soft vinyl chloride, foamed plastic, etc.), rubber (natural rubber, synthetic rubber, etc.), leather, ceramics (multi-layer glass, optical lens, polishing material, etc.), Adhesives for household goods (such as paper), cardboard, bookbinding, and electrical appliances.

Claims (5)

An ethylene oxide adduct of at least one bisphenol compound selected from the group consisting of bisphenol A, bisphenol B, bisphenol E and bisphenol F, wherein the average number of moles of ethylene oxide added is 0.90 to 1 per hydroxyl group 10 and a urethane prepolymer obtained by reacting an ethylene oxide adduct (A) having a monodispersity of 80% or more represented by the following formula (1), a polymer polyol (B), and an organic polyisocyanate (D). A reactive hot melt adhesive containing (C).
Monodispersity (%) = [weight of ethylene oxide adduct (A1) having 1 mol of ethylene oxide added per hydroxyl group / weight of ethylene oxide adduct (A)] × 100 (1) The adhesive according to claim 1, wherein the polymer polyol (B) is obtained by dispersing a polymer of an ethylenically unsaturated compound in a difunctional to tetrafunctional polyether polyol. The adhesive according to claim 1 or 2, wherein the content of the ethylene oxide adduct (A) based on the total weight of the ethylene oxide adduct (A) and the polymer polyol (B) is 10 to 25% by weight. Hardened | cured material formed by hardening | curing the adhesive agent of any one of Claims 1-3. The adhesive body which adhere | attaches a to-be-adhered body with the adhesive agent of any one of Claims 1-3.