JPH0873699A - Block copolymer composition for tacky adhesive - Google Patents

Abstract

PURPOSE: To obtain a hot-melt composition having excellent initial tack, bond strength, creep characteristics, low melt viscosity, excellent weather resistance and melt stability, by blending specific two kinds of epoxy-modified hydrogenated block copolymers in a prescribed ratio. CONSTITUTION: This composition comprises an epoxy-modified hydrogenated block copolymer of the formula, A-(B-A)n and the formula, [(A-B)n ]m+1 -X [(m) and (n) are each >=1; X is a polyfunctional coupling agent residue] which is composed of (A) a polymer block consisting essentially of a vinyl aromatic compound and (B) a polymer block consisting essentially of a conjugated diene block and is prepared by partially hydrogenating the double bond of the unsaturated carbon of the conjugated diene part and epoxidizing part of the rest and an epoxy-modified hydrogenated block copolymer of the formula, C-D or the formula, D-C-D which is composed of (C) a polymer block consisting essentially of a vinyl aromatic compound and (D) a polymer block consisting essentially of a conjugated diene block and is prepared by partially hydrogenating the double bond of the unsaturated carbon of the conjugated diene part and epoxidizing part of the rest in the blending ratio of 80/20 to 20/80(wt.%).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a hot adhesive having excellent initial adhesive strength (tack), adhesive strength (peeling strength / shear strength), creep characteristics (holding power), low melt viscosity and excellent melt stability. The present invention relates to a block copolymer for melt-type pressure-sensitive adhesives.

[0002]

2. Description of the Related Art In recent years, various industrial materials such as laminated films and composite materials have been actively compounded, and as the composite materials have become highly functional, a synthetic resin having a polarity as an adherend. , A non-polar synthetic resin, or a metal such as iron, aluminum, or copper, or a cellulosic material such as wood or paper, or an inorganic material such as glass, as an essential component for complexing different materials, Adhesive polymers are often used as adhesives. The high functionality of these composite materials is achieved by the high functionality of the adhesive polymer used for the adherend.

On the other hand, pressure sensitive adhesives have been conventionally used for various purposes such as pressure sensitive adhesive tapes and labels. The application of the pressure-sensitive adhesive to these tapes has hitherto been carried out by applying a pressure-sensitive adhesive solution in which the pressure-sensitive adhesive is dissolved in a solvent to a substrate using a means such as a roll or a spray. However, it has been recognized that the use of such a solvent has many problems such as air pollution, fire, working environment, and hygiene, and the hot-melt type that does not use a solvent is generally used. It's starting.

This situation also applies to adhesives, and hot-melt adhesives tend to be preferred.

The properties required for such a hot-melt type pressure-sensitive adhesive are: (a) Adhesive properties (tack, peel strength, holding power) are good.

(B) Adhesive properties (peeling strength, shear strength) are good.

Needless to say, from the viewpoint of use as a hot melt, there should be no change in viscosity, coloring, or deterioration of the adhesive properties due to heating and melting.

Good fluidity during melting and excellent coating stability.

Etc. are required.

Particularly in recent years, since the coating apparatus has been improved and the type in which the adhesive is applied in the form of threads from a thin nozzle is being replaced, the melt viscosity is lower and the quality is high even for long-term melt retention. There is a demand for a hot-melt type pressure-sensitive adhesive that has a small change in temperature and has excellent pressure-sensitive adhesive properties. However, in the actual situation, there is no conventional hot-melt type pressure-sensitive adhesive that satisfies all the above requirements.

For example, JP-B-44-17037 and JP-B-47-21720 disclose a hot-melt adhesive method using a block copolymer of styrene-butadiene-styrene or styrene-isoprene-butadiene-styrene. An adhesive is disclosed. However, although these have excellent adhesive strength, they are not easily used stably due to severe deterioration due to heating.

In order to improve the thermal stability, an adhesive using a styrene-ethylene / butylene-styrene block copolymer having a conjugated diene moiety hydrogenated is disclosed in US Pat. No. 3,427,269 and JP-B-55-27. It is disclosed in Japanese Patent No. 7875. However, although the thermal stability of these is improved by hydrogenation, the viscous adhesive force is significantly reduced. Moreover, since the melt viscosity is high, the use conditions are limited, and the type of tackifier used is also limited.

Japanese Unexamined Patent Publication (Kokai) No. 2-1788 discloses that a hydrogenated block copolymer in which a triblock structure and a specific block structure are combined is used. However, in this combination, the melt viscosity, tack, and holding power are poorly balanced, and tack is particularly insufficient. In addition, JP-A 1-20
Japanese Patent No. 284 discloses an adhesive using a block copolymer having a specific hydrogenation rate, but this tacky adhesive composition has insufficient tack and melt viscosity.

In addition, for applications in which the adhesive strength is further increased by curing after cross-linking after adhesion, a block copolymer hydrogenated to an extent sufficient for thermal stability cannot be used because it has no reactive sites. At present, the thermal stability is reduced and a certain amount of double bonds are left, or glycidyl groups are introduced by graft modification, but the amount of functional groups that can be introduced by graft modification is not very large, so it is satisfactory. Crosslink density cannot be obtained.

The inventors of the present invention filed Japanese Patent Application No. 6-208797 [1994-September 1
In [Japanese application], it was proposed that the epoxy-modified block copolymer is useful as an adhesive polymer, but there is a problem in thermal stability when melted and retained, and workability is somewhat unsatisfactory.

[0016]

SUMMARY OF THE INVENTION An object of the present invention is to have excellent melt-adhesive properties such as holding power while having a low melt viscosity, and to obtain melt-viscosity and sticky-adhesive properties against melt retention. An object of the present invention is to provide an excellent polymer for hot-melt pressure-sensitive adhesives, which exhibits little change.

[0017]

Means for Solving the Problems As a result of earnest studies to improve the above-mentioned problems, the present inventors have found that as a measure to reduce the double bond in the conjugated diene moiety, which causes thermal deterioration, in addition to hydrogenation, epoxy is used. It was found that the combined use of the chemical formula improves the thermal stability while maintaining the viscous adhesive force, and further that the melt viscosity can be lowered by using a block copolymer having a specific block structure by mixing. The present invention has been completed.

That is, the present invention provides the following "(a) and (b) (a) a polymer block A mainly containing a vinyl aromatic compound and a polymer block B mainly containing a conjugated diene compound.
Consisting of and hydrogenating a part of the unsaturated carbon double bond of the conjugated diene moiety of the block copolymer represented by the following general formula, the remaining unsaturated carbon double bond of the conjugated diene moiety Epoxy-modified hydrogenated block copolymer partially epoxidized; A- (BA) _n , [(A-B) _n ] _{m + 1} -X << where n and m are integers of 1 or more, X Is a polyfunctional coupling agent residue >> (b) Polymer block C mainly containing vinyl aromatic compounds and polymer block D mainly containing conjugated diene compounds
Consisting of and hydrogenating a part of the unsaturated carbon double bond of the conjugated diene moiety of the block copolymer represented by the following general formula, the remaining unsaturated carbon double bond of the conjugated diene moiety It is composed of an epoxy-modified hydrogenated block copolymer C-D or D-C-D partially epoxidized, and the compounding ratio of (a) and (b) is 80/20 to 20/80 (% by weight). A certain block copolymer composition for adhesives ".

The first feature of the present invention is that, as a measure for saturating the double bond of the conjugated diene moiety to improve the thermal stability, epoxidation is used in combination with conventional hydrogenation. Especially.

This makes it possible to improve the thermal stability while maintaining the viscous adhesive force which has been conventionally sacrificed by hydrogenation, and to lower the melt viscosity as a characteristic of epoxidation. Furthermore, since the amount of the epoxy groups introduced is relatively large, a sufficient crosslink density can be obtained even for applications in which the adhesive is cured by crosslinking after adhesion.

The second feature of the present invention is that by using a block copolymer having a specific block structure as a mixture, the melt viscosity can be further reduced and the workability can be greatly improved. Can be achieved.

The present invention will be described in detail below.

Examples of vinyl aromatic compounds constituting the block polymer used in the present invention include styrene and α-
Methylstyrene, vinyltoluene, p-tertiary butylstyrene, divinylbenzene, p-methylstyrene, 1,
One or more kinds can be selected from 1-diphenylstyrene, vinylnaphthalene, vinylanthracene and the like, and among them, styrene is preferably used in terms of cost. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-
One type or two or more types are selected from 1,3-octadiene, phenyl-1,3-butadiene and the like, and among them, butadiene, isoprene and a combination thereof are preferably used in terms of cost.

The block copolymer referred to herein is a block copolymer composed of a polymer block mainly containing a vinyl aromatic compound and a polymer block mainly containing a conjugated diene compound. The vinyl aromatic compound The copolymerization ratio of the conjugated diene compound and the conjugated diene compound is 5/95 to 70/30, especially 10/90 to 60 /
A polymerization ratio of 40 is preferred. The number average molecular weight of the block copolymer used in the present invention is 5000 to 600,000, preferably 10
The molecular weight distribution [ratio of the weight average molecular weight (Mw) and the number average molecular weight (Mn) (Mw / M is in the range of 000 to 500000).
n)]) is 10 or less.

The copolymerization ratio, the molecular weight and the molecular weight distribution limited here are within the range generally used as a styrene thermoplastic elastomer, and it is not possible to use a special one outside this range. In the invention, it is merely difficult to obtain and the cost is increased.

The molecular structure of the block polymer (a) of the present invention is represented by the following general formula.

A- (BA) _n , [(A-B) _n ] _{m + 1} -X where n and m are integers of 1 or more, and A is a polymer block mainly containing a vinyl aromatic compound, B is a polymer block containing a conjugated diene compound as a main component, and X is a polyfunctional coupling agent residue.

The molecular structure of the block polymer (b) of the present invention is represented by the following general formula C-D or D-C-D.

However, C is a polymer block containing a vinyl aromatic compound as a main component, and D is a polymer block containing a conjugated diene compound as a main component. ) As the method for producing the block polymer used in the present invention, any method can be used as long as it has the above-mentioned structure. For example,
Japanese Patent Publication No. 40-23798, Japanese Publication No. 43-17979, Japanese Publication No. 46-32415
According to the method described in JP-B No. 56-28925, a vinyl aromatic compound-conjugated diene compound block copolymer can be synthesized in an inert solvent using a lithium catalyst or the like. Further, Japanese Examined Patent Publication No. 42-8704 and Japanese Examined Patent Publication No. 43-663.
According to the method described in JP-A No. 6-63 or JP-A No. 59-133203, hydrogenation is carried out in the presence of a hydrogenation catalyst in an inert solvent to give a partially hydrogenated block co-polymer used in the present invention. Coalescence can be synthesized.

The degree of hydrogenation can be known by measuring the NMR of the block copolymer before and after hydrogenation, and is represented by the hydrogenation rate or the hydrogenation rate for short. It is defined as the percentage of hydrogenated double bonds derived from the conjugated diene compound of the unepoxidized raw material block copolymer.

The hydrogenation rate in the present invention is preferably 80% or less because double bonds which can be epoxidized do not exist when hydrogenation is completed.

The method of epoxy-modifying these block copolymers is not particularly limited in the present invention. For example, a vinyl aromatic compound-conjugated diene compound block copolymer may be hydroperoxides in an inert solvent,
It can be obtained by reacting with an epoxidizing agent such as peracids.

As the inert solvent, for example, hexane, cyclohexane, toluene, benzene, ethyl acetate, carbon tetrachloride, chloroform and the like can be used.

Hydroperoxides include hydrogen peroxide, tertiary butyl hydroperoxide, cumene peroxide and the like. Examples of peracids include formic acid, peracetic acid, perbenzoic acid, and trifluoroperacetic acid. Of these, peracetic acid is a preferred epoxidizing agent because it is industrially produced in large quantities, is inexpensively available, and has high stability. Further, a catalyst can be used if necessary in the epoxidation. For example, in the case of peracids, an alkali such as sodium carbonate or an acid such as sulfuric acid can be used as a catalyst.

There is no strict restriction on the amount of epoxidizing agent, and the optimum amount in each case is variable, such as the individual epoxidizing agent used, the desired degree of epoxidation, the individual block copolymer used, etc. Determined by factors.

There are no strict restrictions on the epoxidation reaction conditions. The reaction temperature range that can be used depends on the reactivity of the epoxidizing agent used. For example, peracetic acid is 0
70 ° C. is preferable, and decomposition of peracetic acid occurs above 70 ° C. No special manipulation of the reaction mixture is necessary, for example the mixture may be stirred for 2-10 hours. Isolation of the obtained epoxy-modified copolymer can be carried out by a suitable method, for example, a method of precipitating with a poor solvent, a method of charging the polymer in hot water with stirring, and removing the solvent by distillation.

The degree of epoxidation of the block copolymer for adhesives in the present invention is calculated by the following formula after titration with 0.1 N hydrobromic acid.

Epoxy equivalent = 10000 × W / (f × V) where W is the weight of the block copolymer used for titration (g), V is the titration amount of 0.1 N hydrobromic acid (ml), f
Is a factor of hydrobromic acid.

The epoxidation rate in the present invention means
It is the percentage of the epoxidized double bonds derived from the conjugated diene compound of the unhydrogenated / non-epoxidized raw material block copolymer, and is calculated from the epoxy equivalent by the following formula.

Epoxidation rate = [10000 × D + 2 × H × (10
0-S)] / [(N-16) × (100-S)] where D is the molecular weight of the conjugated diene, H is the hydrogenation rate (%),
S is the content (%) of the vinyl aromatic compound, and N is the epoxy equivalent.

The epoxidation rate of the block copolymer for adhesives in the present invention is 10 to 40%. On the other hand, if the amount of the introduced epoxy group is too small, a sufficient effect cannot be expected.However, if an excessive amount of the epoxy group is introduced, the reaction activity of the epoxy group becomes too high and gelation tends to occur, which rather deteriorates the thermal stability. To do.

Further, in the block copolymer for pressure-sensitive adhesives of the present invention, the conjugated diene moiety which remains unsaturated without being hydrogenated or epoxidized is 90% of the whole conjugated diene.
It is less than 40%, particularly preferably 40% or less from the viewpoint of thermal stability.

The compounding ratio (a) / (b) of the block copolymers (a) and (b) of the block copolymer composition for tackiness / adhesion in the present invention is 80/20 to 20/80. When the compounding ratio is out of this range, the property of the block copolymer (a) or (b) having a larger amount becomes larger, and the effect of mixing and using cannot be sufficiently obtained.

The block copolymer composition for adhesives according to the present invention can be prepared by separately polymerizing the block copolymers (a) and (b), hydrogenating and epoxy-modifying them, and then mixing them separately. They may be polymerized and mixed before hydrogenation or epoxidation, or a composition may be prepared by a charging method such that such a composition is obtained during polymerization.

The block copolymer composition for tacky-adhesives obtained by the present invention has excellent tacky-adhesive performance by itself, but other thermoplastic elastomers (polyolefin-based, polystyrene-based, nylon-based, polyester-based ), Thermoplastic resins (polyolefin-based, polystyrene-based, nylon-based, polyester-based) and known structural adhesives are also used as a part of the embodiments of the present invention.

If necessary, a tackifier, a softening agent,
Reinforcing resins, antioxidants, ultraviolet absorbers, colorants and the like may be added. As the tackifier, those conventionally used in hot-melt adhesives as tackifiers can be used as they are, for example, coumarone / indene resin, phenol resin, p-tert-butylphenol / acetylene resin, phenol / formaldehyde resin, Terpen
Phenolic resin, polyterpene resin, xylene-formaldehyde resin, synthetic polyterpene resin, aromatic hydrocarbon resin, aliphatic cyclic hydrocarbon resin, mono-olefin or di-olefin oligomer, hydrogenated hydrocarbon resin,
Hydrocarbon-based tackifying resin, polybutene, polyhydric alcohol ester of rosin, hydrogenated terpene resin, hydrogenated rosin, hydrogenated wood rosin, ester of hydrogenated rosin and monoalcohol or polyhydric alcohol, turpentine tackifier, etc. Can be mentioned.

More specifically, those described in "Rubber-Plastic Blended Chemicals" (edited by Rubber Digest) can be used.

The softening agent is a petroleum softening agent (paraffin oil, naphthene oil, aroma oil, etc.), paraffin, vegetable oil softening agent, plasticizer, and the like. Compounded medicine "
(Rubber Digest Co., Ltd.) can be used. The softening agent is 5 to 200 parts by weight, based on 100 parts by weight of the block copolymer composition for adhesives, depending on the appropriate viscosity and hardness required for each application of the adhesive composition. It is preferably used in the range of 20 to 100 parts by weight.

These compounding agents can be mixed with the block copolymer composition for adhesives of the present invention by a method such as melt mixing or dry blending.

The block copolymer composition for tacky-adhesives of the present invention is used as an adhesive, particularly a structural adhesive, in the form of powder, pellets, sheets or films, for example, 2 to the adherend. Co-extrusion method using a three-layer bottle molding machine, three-layer inflation molding machine, extrusion coating method for coating preheated material to be coated by extrusion molding, T-die film (sheet) molding machine, inflation molding machine, etc. The adhesive layer is formed by various known methods, such as an adhesive film (sheet) method of thermocompressing the formed film (sheet), a method of powdering the metal surface to an electrostatic coating machine, powder coating using a fluidized dipping device, and the like. be able to.

The block copolymer composition for adhesives of the present invention can also be used as an adhesive for various sheets and tapes, and since no solvent is used, it is used in the field of sanitary materials such as diapers and sanitary napkins. Can be used for, and its industrial utility value is extremely high.

The following examples are provided to describe the present invention more specifically, but the present invention is in no way limited by these examples.

<Synthesis Example 1 / Partially Hydrogenated Block Copolymer A
Preparation> In a nitrogen atmosphere, a stainless steel polymerization kettle equipped with a stirrer was charged with a cyclohexane solution containing 7.5 parts by weight of styrene, a hexane solution containing 0.032 parts by weight of n-butyllithium was added, and polymerization was carried out at 60 ° C for 1 hour. did. Then, a cyclohexane solution containing 17.5 parts by weight of butadiene was added and polymerization was carried out for 3 hours. Then, a cyclohexane solution containing 0.064 parts by weight of n-butyllithium and 52.5 parts by weight of butadiene was added and polymerization was carried out for 1.5 hours. In addition, styrene
A cyclohexane solution containing 22.5 parts by weight was added and polymerization was carried out for 1 hour.

Subsequently, Example 1 of JP-A-59-133203
According to the method described in any one of 1 to 9, hydrogenation reaction was carried out at 60 ° C. using a palladium-carbon supported catalyst and 50 kgf / cm ² of hydrogen gas. The hydrogenation rate was controlled by the amount of hydrogen gas supplied. The partially hydrogenated block copolymer solution obtained was 2,6-
Di-tert-butyl-4-methylphenol 0. 5 parts by weight and tris (nonylphenyl) phosphite 0. 5 parts by weight was added and the solvent was removed by heating to obtain a partially hydrogenated block copolymer.

The number average molecular weight is measured by GPC,
It was calculated as a polystyrene conversion value. The hydrogenation rate was determined by measuring NMR (270 MHz) of the block copolymer before and after the hydrogenation reaction with deuterated chloroform.

Table 1 shows a list of the partially hydrogenated block copolymers synthesized.

<Synthesis Example 2 / Partially Hydrogenated Block Copolymer B
Preparation> In a nitrogen atmosphere, a cyclohexane solution containing 15 parts by weight of styrene was charged into a stainless steel polymerization kettle equipped with a stirrer, added with a hexane solution containing 0.064 parts by weight of n-butyllithium, and polymerized at 60 ° C for 1 hour. did. Then add a cyclohexane solution containing 70 parts by weight of butadiene and add 3
Polymerized for hours. Then, a cyclohexane solution containing 15 parts by weight of styrene was added and polymerization was carried out for 1 hour.

Subsequently, Example 1 of JP-A-59-133203
According to the method described in any one of 1 to 9, hydrogenation reaction was carried out at 60 ° C. using a palladium-carbon supported catalyst and 50 kgf / cm ² of hydrogen gas. The hydrogenation rate was controlled by the amount of hydrogen gas supplied. The partially hydrogenated block copolymer solution obtained was 2,6-
Di-tert-butyl-4-methylphenol 0. 5 parts by weight and tris (nonylphenyl) phosphite 0. 5 parts by weight was added and the solvent was removed by heating to obtain a partially hydrogenated block copolymer.

The number average molecular weight is measured by GPC,
It was calculated as a polystyrene conversion value. The hydrogenation rate was determined by measuring NMR (270 MHz) of the block copolymer before and after the hydrogenation reaction with deuterated chloroform.

Table 1 shows a list of the partially hydrogenated block copolymers synthesized.

<Synthesis Example 3 / Partially Hydrogenated Block Copolymer C
Preparation> A cyclohexane solution containing 15 parts by weight of styrene was charged into a stainless steel polymerization kettle equipped with a stirrer under a nitrogen atmosphere, and a hexane solution containing 0.128 parts by weight of n-butyllithium was added, followed by polymerization at 60 ° C for 1 hour. did. Then add a cyclohexane solution containing 70 parts by weight of butadiene and add 3
Polymerized for hours. Then, a cyclohexane solution containing 15 parts by weight of styrene was added and polymerization was carried out for 1 hour.

Subsequently, Example 1 of JP-A-59-133203
According to the method described in any one of 1 to 9, hydrogenation reaction was carried out at 60 ° C. using a palladium-carbon supported catalyst and 50 kgf / cm ² of hydrogen gas. The hydrogenation rate was controlled by the amount of hydrogen gas supplied. The partially hydrogenated block copolymer solution obtained was 2,6-
Di-tert-butyl-4-methylphenol 0. 5 parts by weight and tris (nonylphenyl) phosphite 0. 5 parts by weight was added and the solvent was removed by heating to obtain a partially hydrogenated block copolymer.

The number average molecular weight is measured by GPC,
It was calculated as a polystyrene conversion value. The hydrogenation rate was determined by measuring NMR (270 MHz) of the block copolymer before and after the hydrogenation reaction with deuterated chloroform.

Table 1 shows a list of the partially hydrogenated block copolymers synthesized.

<Synthesis Example 4 / Preparation of partially hydrogenated block copolymers D, E and F> Synthesized by the above (I) to Synthesis Example 3 in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer. Partially hydrogenated block copolymer 300 g, ethyl acetate 1500
g was added and dissolved. Then, a predetermined amount of a 30% by weight ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours while stirring. The reaction crude liquid was purified by extracting with water to remove by-products. The reaction solution was returned to room temperature, taken out from the reactor, and subjected to steam stripping to remove the solvent. Finally, it was dried to remove water. Table 2 shows a list of the synthesized epoxidized partially hydrogenated block copolymers.

Example / Evaluation of partially hydrogenated block copolymer The following items were measured. The measurement results are shown in Table 3.

Shear strength: SUS304 was used as the adherend, and the shear strength was measured according to JIS K6850.

Peel strength: SUS304 was used as the adherend and aluminum foil was used as the carrier of the adhesive, and the peel strength from the SUS surface was measured according to JIS K6854.

Melt viscosity Using a flow tester, temperature 180 ° C., die 1 mmφ ×
It measured at 10 mm and 5 minutes of preheating.

[Example 1, Comparative Examples 1 to 5] Comparative Examples 2 and 3 are general triblock type partially hydrogenated block copolymers, and Comparative Example 1 is a block copolymer composition of the present invention. It is an unepoxidized product. Although the melt viscosity was low, it was not at a satisfactory level and the adhesive strength was not improved at all. On the other hand, Comparative Examples 4 and 5
Is an epoxide of a general triblock type partially hydrogenated block copolymer. The adhesive strength is improved, but the melt viscosity is slightly lowered. On the other hand, in the examples of the present invention, the adhesive force is improved, and the melt viscosity is remarkably reduced particularly under a low load, and the workability is greatly improved.

Table 1 Polymer number average molecular weight S / B ratio (a) / (b) ratio Hydrogenation rate (% by weight) (%) A 66300 30 50/50 33 B 101000 30 50/0 35 C 54100 30 50 / 0 39 Table 2 Polymer Raw material Polymer Epoxy equivalent Epoxidation rate Hydrogenation rate Residual unsaturation (g / mol) (%) (%) (%) DA 326 25 33 42 E B 336 24 35 41 F C 338 24 39 37 Table 3 Experimental Example Polymer-shear Peeling Melt viscosity Melt viscosity Melt viscosity Load 50kgf Load 100kgf Load 150kgf Example 1 D 50 8 1800 910 560 Comparative Example 1 A 24 4 3000 960 530 Comparative Example 2 B 27 5 No flow 10000 7000 Comparative Example 3 C 34 5 3500 1000 550 Comparative Example 4 E 40 10 15000 6000 3500 Comparative Example 5 F 43 10 3000 900 520 In Table 3 above, the shear is SUS304, the unit is kgf / cm ² ,
The exfoliation is SUS304, the unit is kgf / 25mm, the unit of melt viscosity is
Poi for load 50kgf, load 100kgf, load 150kgf
It is se.

[0072]

INDUSTRIAL APPLICABILITY The block copolymer composition for adhesives obtained by the present invention is particularly useful as a structural adhesive. That is, since a hydrogenated block copolymer composition having excellent heat resistance, weather resistance, and mechanical properties is used as a base and an epoxy group as a functional group is further introduced, adhesion to various adherends by a heating reaction is performed. It can give a high degree of sex. Therefore, the block copolymer composition for pressure-sensitive adhesives of the present invention, various metals, inorganic materials, paper, wood, other various thermoplastic elastomers, adherends such as thermoplastic resin, firmly under melting Bonds and gives a structural adhesive with excellent adhesive strength, heat resistance, and weather resistance.

Also as a pressure-sensitive adhesive, the block copolymer composition for pressure-sensitive adhesives of the present invention provides a hot-melt pressure-sensitive adhesive having a well-balanced melt viscosity, pressure-sensitive adhesive property, and thermal stability.

(The margin below)

Claims (2)

[Claims] 1. (a) and (b) (a) A polymer block A containing a vinyl aromatic compound as a main component and a polymer block B containing a conjugated diene compound as a main component.
Consisting of and hydrogenating a part of the unsaturated carbon double bond of the conjugated diene moiety of the block copolymer represented by the following general formula, the remaining unsaturated carbon double bond of the conjugated diene moiety Epoxy-modified hydrogenated block copolymer partially epoxidized; A- (BA) _n , [(A-B) _n ] _{m + 1} -X << where n and m are integers of 1 or more, X Is a polyfunctional coupling agent residue >> (b) Polymer block C mainly containing vinyl aromatic compounds and polymer block D mainly containing conjugated diene compounds
Consisting of and hydrogenating a part of the unsaturated carbon double bond of the conjugated diene moiety of the block copolymer represented by the following general formula, the remaining unsaturated carbon double bond of the conjugated diene moiety It is composed of an epoxy-modified hydrogenated block copolymer C-D or D-C-D partially epoxidized, and the compounding ratio of (a) and (b) is 80/20 to 20/80 (% by weight). A block copolymer composition for an adhesive. 2. The hydrogenation rate is more than 0% and 80% or less, and the epoxidation rate is 10% or more and 40% or less with respect to 100% of the double bond of the unsaturated carbon of the conjugated diene moiety. 5% or more and 90% or less of the remaining double bonds (however,
The total of the three is 100%), The block copolymer composition for adhesives according to claim 1.