Thermoplastic polymer composition, layered body, and protective film

Abstract

Provided is a thermoplastic polymer composition containing an aromatic vinyl-based block copolymer (a-1) having a number average molecular weight of 30,000 to 200,000, the aromatic vinyl-based block copolymer containing a polymer block F containing a structural unit derived from an aromatic vinyl-based monomer as a main component and a hydrogenated or non-hydrogenated polymer block G containing a structural unit derived from a conjugated diene monomer or an isobutylene monomer as a main component; an acrylic polymer (a-2); an olefin-based polymer containing polar groups (a-3); and a softening agent (a-4), at the proportions that satisfy the following Expressions (1) to (3):
0.05W.sub.(a-2)/W.sub.(a-1)9(1)
0.1<W.sub.(a-3)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.9(2), and
0W.sub.(a-4)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.5(3)
wherein W.sub.(a-1), W.sub.(a-2), W.sub.(a-3) and W.sub.(a-4) represent the contents (on a mass basis) of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), respectively, in the thermoplastic polymer composition.

Claims

1. A thermoplastic polymer composition consisting of: an aromatic vinyl-based block copolymer (a-1) having a number average molecular weight of 30,000 to 200,000, the aromatic vinyl based block copolymer (a-1) comprising: a polymer block F comprising a structural unit derived from an aromatic vinyl-based monomer as a main component; and a hydrogenated or non-hydrogenated polymer block G comprising a structural unit derived from a conjugated diene monomer or an isobutylene monomer as a main component; an acrylic polymer (a-2); an olefin-based polymer containing polar groups (a-3); optionally, a softening agent (a-4); and optionally, a component other than the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) or softening agent (a-4) in an amount of 30 parts by mass or less with respect to 100 parts by mass of a total amount of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), at the proportions satisfying the following Expressions (1) to (3):
0.05W.sub.(a-2)/W.sub.(a-1)9(1),
0.15<W.sub.(a-3)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.9(2), and
0W.sub.(a-4)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.5(3) wherein W.sub.(a-1), W.sub.(a-2), W.sub.(a-3) and W.sub.(a-4) represent the contents (on a mass basis) of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), respectively, in the thermoplastic polymer composition, and wherein the polymer block F has a number average molecular weight of 1,000 to 50,000, the polymer block G comprises: a polymer block g1, which is a polymer block having a number average molecular weight of 1,000 to 30,000 and in which the content of a 1,4-bond structural unit derived from the conjugated diene monomer that constitutes the polymer block is less than 30 mol %; and a polymer block g2, which is a polymer block having a number average molecular weight of 25,000 to 190,000 and in which the content of a 1,4-bond structural unit derived from the conjugated diene monomer that constitutes the polymer block is 30 mol % or more, and the aromatic vinyl-based block copolymer (a-1) comprises at least one (F-g1-g2) structure.

2. The thermoplastic polymer composition according to claim 1, wherein the ratio of the shear viscosity Ea (Pa.Math.s) at a shear velocity 1 (1/s) measured at 210 C. to the shear viscosity Eb (Pa.Math.s) at a shear velocity 100 (1/s) measured at 210 C., (Ea/Eb), is 10 or less.

3. The thermoplastic polymer composition according to claim 1, wherein the aromatic vinyl-based monomer is a-methylstyrene.

4. The thermoplastic polymer composition according to claim 1, wherein the olefin-based polymer containing polar groups (a-3) is at least one selected from an ethylene-vinyl acetate copolymer, an ethylene-(meth)acrylic acid ester copolymer, and an ethylene-(meth)acrylic acid copolymer.

5. A laminate comprising: a layer (A) formed from a thermoplastic polymer composition; a pressure-sensitive adhesive layer (B) comprising an acrylic pressure-sensitive adhesive; and a substrate layer (C) comprising a polyolefin-based polymer, wherein the layer (A), the pressure-sensitive adhesive layer (B), and the substrate layer (C) are laminated in the order of (B)-(A)-(C), and wherein the thermoplastic polymer composition consists of: an aromatic vinyl-based block copolymer (a-1) having a number average molecular weight of 30,000 to 200,000, the aromatic vinyl based block copolymer (a-1) comprising: a polymer block F comprising a structural unit derived from an aromatic vinyl-based monomer as a main component; and a hydrogenated or non-hydrogenated polymer block G comprising a structural unit derived from a conjugated diene monomer or an isobutylene monomer as a main component; an acrylic polymer (a-2); an olefin-based polymer containing polar groups (a-3); optionally, a softening agent (a-4); and optionally, a component other than the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) or softening agent (a-4) in an amount of 30 parts by mass or less with respect to 100 parts by mass of a total amount of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), at the proportions satisfying the following Expressions (1) to (3):
0.05W.sub.(a-2)/W.sub.(a-1)9(1),
0.15<W.sub.(a-3)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.9(2), and
0W.sub.(a-4)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.5(3) wherein W.sub.(a-1), W.sub.(a-2), W.sub.(a-3) and W.sub.(a-4) represent the contents (on a mass basis) of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), respectively, in the thermoplastic polymer composition.

6. The laminate according to claim 5, wherein the acrylic pressure-sensitive adhesive comprises: an acrylic block copolymer (b-1) comprising at least one polymer block (I-1) composed of a structural unit derived from a methacrylic acid ester; and at least one polymer block (I-2) composed of a structural unit derived from an acrylic acid ester.

7. The laminate according to claim 6, wherein the content of the polymer block (I-1) in the acrylic block copolymer (b-1) is 5% by mass to 50% by mass.

8. The laminate according to claim 6, wherein the structural unit derived from the acrylic acid ester that constitutes the polymer block (I-2) is derived from an acrylic acid ester (i-1) represented by formula: CH.sub.2CHCOOR.sup.1 (P), wherein R.sup.1 represents an organic group having 4 to 6 carbon atoms, and an acrylic acid ester (i-2) represented by formula: CH.sub.2CHCOOR.sup.2 (Q), wherein R.sup.2 represents an organic group having 7 to 12 carbon atoms, and the mass ratio of the acrylic acid ester (i-1) to the acrylic acid ester (i-2), ((i-1)/(i-2)), is from 90/10 to 10/90.

9. The laminate according to claim 5, wherein the ratio of the shear viscosity Ex (Pa.Math.s) at a shear velocity 1 (1/s) measured at 210 C. to the shear viscosity Ey (Pa.Math.s) at a shear velocity 100 (1/s) measured at 210 C., (Ex/Ey), of the acrylic pressure-sensitive adhesive is 25 or less.

10. The laminate according to claim 5, wherein the absolute value of the difference between the ratio (Ea/Eb) of the shear viscosity Ea (Pa.Math.s) at a shear velocity 1 (1/s) measured at 210 C. to the shear viscosity Eb (Pa.Math.s) at a shear velocity 100 (1/s) measured at 210 C. of the thermoplastic polymer composition, and the ratio (Ex/Ey) of the shear viscosity Ex (Pa.Math.s) at a shear velocity 1 (1/s) measured at 210 C. to the shear viscosity Ey (Pa.Math.s) at a shear velocity 100 (1/s) measured at 210 C. of the acrylic pressure-sensitive adhesive, is 10 or less.

11. The laminate according to claim 5, wherein the polyolefin-based polymer that constitutes the substrate layer (C) is a polypropylene-based polymer.

12. The laminate according to claim 5, wherein the layers of (A) to (C) are laminated using a co-extrusion molding processing method.

13. A protective film comprising the laminate according to claim 5.

14. A thermoplastic polymer composition consisting of: an aromatic vinyl-based block copolymer (a-1) having a number average molecular weight of 30,000 to 200,000, the aromatic vinyl based block copolymer (a-1) comprising: a polymer block F comprising a structural unit derived from an aromatic vinyl-based monomer as a main component; and a hydrogenated or non-hydrogenated polymer block G comprising a structural unit derived from a conjugated diene monomer or an isobutylene monomer as a main component; an acrylic polymer (a-2); an olefin-based polymer containing polar groups (a-3); optionally, a softening agent (a-4); and optionally, a component other than the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) or softening agent (a-4) in an amount of 30 parts by mass or less with respect to 100 parts by mass of a total amount of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), at the proportions satisfying the following Expressions (1) to (3):
0.05W.sub.(a-2)/W.sub.(a-1)9(1),
0.15<W.sub.(a-3)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.9(2), and
0W.sub.(a-4)/(W.sub.(a-1)+W.sub.(a-2)+W.sub.(a-3)+W.sub.(a-4))0.5(3) wherein W.sub.(a-1), W.sub.(a-2), W.sub.(a-3) and W.sub.(a-4) represent the contents (on a mass basis) of the aromatic vinyl-based block copolymer (a-1), acrylic polymer (a-2), olefin-based polymer containing polar groups (a-3) and softening agent (a-4), respectively, in the thermoplastic polymer composition, and wherein the content of structural units having the polar group in the olefin-based polymer containing polar groups (a-3) is from 5% by mass to 50% by mass.

15. The thermoplastic polymer composition according to claim 14, wherein the content of structural units having the polar group in the olefin-based polymer containing polar groups (a-3) is from 10% by mass to 30% by mass.

16. The thermoplastic polymer composition according to claim 14, wherein the ratio of the shear viscosity Ea (Pa.Math.s) at a shear velocity 1 (1/s) measured at 210 C. to the shear viscosity Eb (Pa.Math.s) at a shear velocity 100 (1/s) measured at 210 C., (Ea/Eb), is 10 or less.

17. The thermoplastic polymer composition according to claim 14, wherein the polymer block F has a number average molecular weight of 1,000 to 50,000, the polymer block G comprises: a polymer block g1, which is a polymer block having a number average molecular weight of 1,000 to 30,000 and in which the content of a 1,4-bond structural unit derived from the conjugated diene monomer that constitutes the polymer block is less than 30 mol %; and a polymer block g2, which is a polymer block having a number average molecular weight of 25,000 to 190,000 and in which the content of a 1,4-bond structural unit derived from the conjugated diene monomer that constitutes the polymer block is 30 mol % or more, and the aromatic vinyl-based block copolymer (a-1) comprises at least one (F-g1-g2) structure.

18. The thermoplastic polymer composition according to claim 14, wherein the aromatic vinyl-based monomer is -methylstyrene.

19. The thermoplastic polymer composition according to claim 14, wherein the olefin-based polymer containing polar groups (a-3) is at least one selected from an ethylene-vinyl acetate copolymer, an ethylene-(meth)acrylic acid ester copolymer, and an ethylene-(meth)acrylic acid copolymer.

Description

EXAMPLES

(1) Hereinafter, the invention will be specifically explained by means of Examples and the like, but the invention is not intended to be limited to these Examples. Meanwhile, the various physical properties in the Examples and Comparative Examples were measured or evaluated by the following methods.

(2) [Methods for Measurement or Evaluation]

(3) <1. Weight Average Molecular Weights (Mw), Number Average Molecular Weights (Mn) and Molecular Weight Distributions (Mw/Mn) of Aromatic Vinyl-Based Block Copolymer (a-1) and Acrylic Block Copolymer (b-1)>

(4) These were determined as molecular weights relative to polystyrene standards by gel permeation chromatography (hereinafter, abbreviated to GPC). Apparatus: GPC apparatus HLC-8020 (manufactured by Tosoh Corp.) Separating columns: TSKgel GMHXL, G4000HXL and G5000HXL manufactured by Tosoh Corp. were connected in series. Eluent: Tetrahydrofuran Flow rate of eluent: 1.0 ml/min Column temperature: 40 C. Detection method: Differential refractive index (RI)
<2. Content of Polymer Block F and Amount of 1,4-Bonds of Polymer Block G in Aromatic Vinyl-Based Block Copolymer (a-1), and Contents of Various Polymer Blocks in Acrylic Block Copolymer (b-1)>

(5) These were determined by a .sup.1H-NMR analysis. Apparatus: Nuclear magnetic resonance apparatus JNM-ECX400 (manufactured by JEOL, Ltd.) Solvent: Deuterated chloroform
<3. Melting Point>

(6) A sample that had been fused by heating the sample from 30 C. to 250 C. at a rate of temperature increase of 10 C./rain was cooled from 250 C. to 30 C. at a rate of temperature decrease of 10 C./min, and then the sample was heated again from 30 C. to 250 C. at a rate of temperature increase of 10 C./min, using a differential scanning calorimeter (DSC) TGA/DSC1 Star System (manufactured by Mettler Toledo International, Inc.). The peak top temperature of an endothermic peak measured during the process was designated as the melting point.

(7) <4. Tensile Modulus of Polyolefin-Based Polymer>

(8) A polyolefin-based polymer was molded into a sheet having a thickness of 1 mm at 200 C. using a press molding machine, and the tensile modulus thereof was measured according to the method described in ISO 527-3 under the conditions of room temperature (23 C.) and a tensile rate of 300 mm/min.

(9) <5. Melt Flow Rate>

(10) The melt flow rate was measured according to ISO 1133 at the temperature and load described in the table.

(11) <6. Shear Viscosity Ratio (Ea/Eb) of Thermoplastic Polymer Composition>

(12) A sheet having a thickness of 1 mm obtained by molding a thermoplastic polymer composition at 200 C. using a press molding machine was interposed between parallel discs (diameter 25 mm) using a rotary type rheometer ARES (manufactured by Rheometric Scientific, Inc.), and the shear viscosity was calculated by designating the value of complex viscosity * at 210 C. and the shear velocity 1 (1/s), which was measured under the conditions of a strain of 5%, a rate of temperature increase of 5 C./min, and a measurement temperature of 170 C. to 250 C., as shear viscosity Ea (Pa.Math.s), and designating the value of complex viscosity * at 210 C. and the shear velocity 100 (1/s), which was measured under the conditions of 170 C. to 250 C., as shear viscosity Eb (Pa.Math.s).

(13) <7. Shear Viscosity Ratio (Ex/Ey) of Acrylic Pressure-Sensitive Adhesive>

(14) A sheet having a thickness of 1 mm obtained by molding an acrylic pressure-sensitive adhesive at 200 C. using a press molding machine was interposed between parallel discs (diameter 25 mm) using a rotary type rheometer ARES (manufactured by Rheometric Scientific, Inc.), and the shear viscosity was calculated by designating the value of complex viscosity * at 210 C. and the shear velocity 1 (1/s), which was measured under the conditions of a strain of 5%, a rate of temperature increase of 5 C./rain, and a measurement temperature of 170 C. to 250 C., as shear viscosity Ex (Pa.Math.s), and designating the value of complex viscosity * at 210 C. and the shear velocity 100 (1/s), which was measured under the conditions of 170 C. to 250 C., as shear viscosity Ey (Pa.Math.s).

(15) <8. Co-Extrusion Molding Processability>

(16) The laminate of the invention was produced using a three-component three-layer feed block type T-die co-extruder by feeding a thermoplastic polymer composition, an acrylic pressure-sensitive adhesive and a polyolefin-based polymer respectively into different T-dies, under the co-extrusion molding processing conditions described below.

(17) Co-Extrusion Molding Processing Conditions:

(18) Layer Configurations and Thicknesses of Various Layers

(19) The laminate was molded such that the thickness ratio of the pressure-sensitive adhesive layer (B) from the acrylic pressure-sensitive adhesive/the layer (A) formed from the thermoplastic polymer composition/the substrate layer (C) formed from the polyolefin-based polymer=10 m/10 m to 40 m.

(20) Specifications of Extruder and Extrusion Temperature

(21) A single-screw extruder was used. The molding temperatures in the respective extruders at the time of extrusion of the various layers were as follows: the layer (A) formed from the thermoplastic polymer composition: 200 C., the pressure-sensitive adhesive layer (B) formed from the acrylic pressure-sensitive adhesive: 190 C., and the substrate layer (C) formed from the polyolefin-based polymer: 210 C.

(22) Specifications of T-Dies, Feed Blocks and Cooling Rolls, Temperature at the Time of Molding, Withdrawal Condition Range

(23) The width of the T-dies was 300 mm, the temperatures of the adaptor (AD) to a junction of a composition of three components (two components), the T-dies, and the three-component three-layer feed block (molding apparatus at the junction) were all set to 200 C. The temperature of the cooling roll for withdrawing a laminate ejected from the T-dies was 40 C., and the withdrawing rate was 4.0 m/min.

(24) Surging (in which the amount of extrusion in the co-extrusion molding processing is not constant, and the shape or dimension of the product becomes irregular or varies regularly) of the laminate thus obtained, the surface smoothness, and the withdrawability at the time of molding were evaluated according to the evaluation criteria described below, and these were taken as indicators of co-extrusion molding processability.

(25) (Surging)

(26) A laminate was divided uniformly into 10 parts in the width direction, and the cross-sections were observed with an optical microscope Digital Microscope VHX-900 (manufactured by Keyence Corp.). The thickness of each of the layers at the center of each cross-section was measured, and the average value of thicknesses of each the layers (hereinafter, referred to as average thickness) was determined.

(27) Next, for the respective fragments obtained by dividing the laminate, the sites in each layer at which the maximum thickness and the minimum thickness were obtained were selected by checking with a microscope, and those thicknesses were measured. These were respectively taken as the maximum thickness and the minimum thickness of each layer. In the laminate used for the measurement, the coefficient of thickness variation of each layer was calculated by the following formula, using any one of the maximum thickness or the minimum thickness, which gave a larger difference with the average thickness.
Coefficient of thickness variation (%)=100(average thickness)(maximum thickness or minimum thickness)|/(average thickness)
wherein |(average thickness)(maximum thickness or minimum thickness)| means the absolute value of the difference between the (average thickness) and the (maximum thickness or minimum thickness). ++: Among the coefficients of thickness variation of the various layers that constitute the laminate, the maximum value is less than 10%. +: Among the coefficients of thickness variation of the various layers that constitute the laminate, the maximum value is 10% or more but less than 20%. : Among the coefficients of thickness variation of the various layers that constitute the laminate, the maximum value is 20% or more.
(Surface Smoothness)

(28) This was determined by visual inspection. ++: When the laminate thus obtained was held up to visible light and was visually observed, there were no surface irregularities, and the surface was smooth. +: When the laminate thus obtained was held up to visible light and was visually observed, surface irregularities such as melt fractures were observed by visual inspection, and when the laminate was not held up to the light, those surface irregularities were not observed by visual inspection. : Even in a case in which the laminate thus obtained was not held up to light, emboss-like surface irregularities or surface irregularities such as streaks in the flow direction were visually observed.
(Withdraw Ability)

(29) For a laminate that had been withdrawn into a roll (1 m/min in the flow direction), the thickness was measured with a thickness meter at every 10 cm from a position 5 cm away from an end in the flow direction of the laminate, respectively at the position 5 cm away from either end in the width direction of the laminate and at the position at the center in the width direction. In the laminate thus analyzed, the coefficient of thickness variation (%) was calculated by the following formula, using any one of the maximum value of thickness (maximum thickness) or the minimum value of thickness (minimum thickness) of each layer, which gave a larger difference with the thickness average value (average thickness) of the measured values.
Coefficient of thickness variation (%)=100|(average thickness)(maximum thickness or minimum thickness)|/(average thickness)
wherein |(average thickness)(maximum thickness or minimum thickness)|means the absolute value of the difference between the (average thickness) and the (maximum thickness or minimum thickness). ++: The coefficient of thickness variation of the laminate is less than 10%. +: The coefficient of thickness variation of the laminate is 10% or more but less than 20%. : The coefficient of thickness variation of the laminate is 20% or more.
<9. Delamination Resistance of Substrate Layer (C) and Layer (A)>

(30) A laminate produced in the same manner as the method described in the above section 8. except that an acrylic pressure-sensitive adhesive was not used, was cut into a size of a width of 25 mm and a length of 100 mm, and the sample thus obtained was stored for 24 hours at room temperature (23 C.). Subsequently, the delamination resistance was measured by peeling the laminate in the direction of 180 at a rate of 300 mm/min at 23 C. according to ISO 29862 using a measuring instrument 5566 type (manufactured by Instron Corp.), and the delamination resistance was evaluated according to the following evaluation criteria. ++: more than 16 N/25 mm +: 5 N/25 mm to 16 N/25 mm

(31) : less than 5 N/25 mm

(32) <10. Delamination Resistance Between Layer (A) and Pressure-Sensitive Adhesive Layer (B)>

(33) A laminate produced in the same manner as the method described in the above section 8. except that a polyolefin-based polymer was not used, was cut into a size of a width of 25 mm and a length of 100 mm, and the sample thus obtained was stored for 24 hours at room temperature (23 C.). Subsequently, the delamination resistance was measured by peeling the laminate in the direction of 180 at a rate of 300 mm/min at 23 C. according to ISO 29862 using a measuring instrument 5566 type (manufactured by Instron Corp.), and the delamination resistance was evaluated according to the following evaluation criteria. ++: more than 16 N/25 mm +: 5 N/25 mm to 16 N/25 mm : less than 5 N/25 mm
<11. 180 Peeling Strength of Laminate Against Acrylic Resin Plate>

(34) A laminate produced by the method described above was cut into a size of a width of 25 mm and a length of 100 mm, and was bonded to an acrylic resin (PMMA) plate. The sample was stored for 24 hours at room temperature (23 C.), and then the 180 peeling strength was measured by peeling the laminate in the direction of 180 at a rate of 300 mm/min at 23 C. according to ISO 29862 using a measuring instrument 5566 type (manufactured by Instron Corp.).

(35) [Raw Material Polymers Used in Examples]

(36) The details of the raw material polymers used in Examples and Comparative Examples are shown below. Furthermore, their physical properties are shown in Tables 1 to 6.

(37) [Aromatic Vinyl-Based Block Copolymer (a-1)]

[Production Example 1] Production of Aromatic Vinyl-Based Bock Copolymer (1)

(38) 800 g of cyclohexane, 30 g of styrene and 5.2 ml of sec-butyllithium (1.3 M cyclohexane solution) were introduced into a nitrogen-purged pressure-resistant vessel equipped with a stirring apparatus, and the components were polymerized for 60 minutes at 50 C.

(39) Subsequently, 140 g of isoprene was added to this reaction liquid mixture, and polymerization was carried out for 60 minutes. 30 g of styrene was further added thereto, and polymerization was carried out for 60 minutes. Subsequently, methanol was added at the last to terminate the reaction, and thus a polystyrene-polyisoprene-polystyrene triblock copolymer was synthesized.

(40) Into the polymerization reaction solution obtained as described above, a Ziegler hydrogenation catalyst formed from nickel octate and triethylaluminum was added in a hydrogen atmosphere, and a hydrogenation reaction was carried out for 5 hours at 80 C. at a hydrogen pressure of 0.8 MPa. Thus, a hydrogenation product of a polystyrene-polyisoprene-polystyrene triblock copolymer was obtained.

(41) The hydrogenated block copolymer thus obtained was analyzed by GPC, and as a result, the following was found: peak top molecular weight of the main component (Mt)=59,000, number average molecular weight (Mn)=57,600, weight average molecular weight (Mw)=58,000, Mw/Mn=1.01. Also, a .sup.1H-NMR analysis was carried out, and as a result, the content of the polystyrene block in the polystyrene triblock copolymer was 31% by mass, the amount of 1,4-bonds of the polyisoprene block was 93 mol %, and the hydrogenation ratio was 98%.

(42) The melt flow rate at 230 C. under a load of 2.16 kg was 50 g/10 min.

[Production Example 2] Production of Aromatic Vinyl-Based Block Copolymer (2)

(43) 90.9 g of -methylstyrene, 138 g of cyclohexane, 15.2 g of methylcyclohexane, and 3.2 g of tetrahydrofuran were introduced into a nitrogen-purged pressure-resistant vessel equipped with a stirring apparatus. 9.8 ml of sec-butyllithium (1.3 M cyclohexane solution) was added to this liquid mixture, and polymerization was carried out for 3 hours at 10 C. The number average molecular weight (Mn) of poly--methylstyrene after 3 hours from the initiation of the polymerization was 6,600, and the polymerization conversion ratio of -methylstyrene was 89%.

(44) Subsequently, 23 g of butadiene was added to this reaction liquid mixture, polymerization was performed by stirring the reaction liquid mixture for 30 minutes at 10 C., and then 930 g of cyclohexane was added thereto. The polymerization conversion ratio of -methylstyrene at this time point was 89%, and the number average molecular weight (measured by GPC, and calculated relative to polystyrene standards) of a polybutadiene block (g1) thus formed was 3,700, while the amount of 1,4-bonds determined by a .sup.1H-NMR analysis was 19 mol %.

(45) Next, 141.3 g of butadiene was further added to the present reaction liquid, and a polymerization reaction was carried out for 2 hours at 50 C. The number average molecular weight (Mn) of a polybutadiene block (g2) of a block copolymer (structure: F-g1-g2) obtained by sampling at this time point was 29,800, and the amount of 1,4-bonds determined by a .sup.1H-NMR analysis was 60 mol %.

(46) Subsequently, 12.2 ml of dichlorodimethylsilane (0.5 M toluene solution) was added to this polymerization reaction solution, and the mixture was stirred for 1 hour at 50 C. Thus, a poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer was obtained. When the coupling efficiency obtainable at this time was calculated from an area ratio of UV absorption in GPC between a coupled body (poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer: F-g1-g2-X-g2-g1-F; wherein X represents a coupled residue (Si(Me).sub.2-); number average molecular weight (Mn)=81,000) and an unreacted block copolymer (poly--methylstyrene-polybutadiene block copolymer: F-g1-g2, number average molecular weight (Mn)=41,000), the coupling efficiency was 94% by mass. Furthermore, according to the results of a .sup.1H-NMR analysis, the content of a poly--methylstyrene block in the poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer was 30% by mass, and the amount of 1,4-bonds of the entirety of the polybutadiene blocks, that is, the block (g1) and the block (g2), was 60 mol %.

(47) A Ziegler hydrogenation catalyst formed from nickel octate and triethylaluminum was added in a hydrogen atmosphere to the polymerization reaction solution obtained as described above, and a hydrogenation reaction was carried out for 5 hours at 80 C. at a hydrogen pressure of 0.8 MPa. Thus, a hydrogenation product of the poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer was obtained.

(48) The hydrogenated block copolymer thus obtained was analyzed by GPC, and as a result, a main component thereof was a hydrogenation product (coupled body) of a poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer with peak top molecular weight (Mt)=81,000, number average molecular weight (Mn)=78,700, weight average molecular weight (Mw)=79,500, and Mw/Mn=1.01. It was found from the area ratio of UV (254 nm) absorption in GPC that the coupled body was included in an amount of 94% by mass. Furthermore, the hydrogenation ratio of the polybutadiene block composed of block (g1) and block (g2) was found by a .sup.1H-NMR analysis to be 97 mol %.

(49) The melt flow rate at 230 C. under a load of 2.16 kg was 5.0 g/10 min.

[Production Example 3] Production of Aromatic Vinyl-Based Block Copolymer (3)

(50) 90.9 g of -methylstyrene, 138 g of cyclohexane, 15.2 g of methylcyclohexane, and 5.4 g of tetrahydrofuran were introduced into a nitrogen-purged pressure-resistant vessel equipped with a stirring apparatus. 9.8 ml of sec-butyllithium (1.3 M cyclohexane solution) was added to this liquid mixture, and the mixture was polymerized for 3 hours at 10 C. Thus, a polymer block F was formed. The number average molecular weight (Mn) of the poly--methylstyrene (polymer block F) after 3 hours from the initiation of polymerization was 6,600, and the polymerization conversion ratio of -methylstyrene was 89%.

(51) Subsequently, 23 g of butadiene was added to this reaction liquid mixture, polymerization was performed by stirring the reaction liquid mixture for 30 minutes at 10 C., and then 930 g of cyclohexane was added thereto. The polymerization conversion ratio of -methylstyrene at this time point was 89%, the number average molecular weight (measured by GPC and calculated relative to polystyrene standards) of the polybutadiene block (g1) thus formed was 3.700, and the amount of 1,4-bonds determined from a .sup.1H-NMR analysis was 19 mol %.

(52) Next, 141.3 g of butadiene was further added to this reaction liquid, and a polymerization reaction was carried out for 2 hours at 50 C. The number average molecular weight (Mn) of the polybutadiene block (g2) of the block copolymer (structure: A-g1-g2) obtained by sampling at this time point was 29,800, and the amount of 1,4-bonds determined by a .sup.1H-NMR analysis was 47 mol %.

(53) Subsequently, 12.2 ml of dichlorodimethylsilane (0.5 M toluene solution) was added to this polymerization reaction solution, and the mixture was stirred for 1 hour at 50 C. Thus, a poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer was obtained. When the coupling efficiency obtainable at this time was calculated from the area ratio of UV absorption in GPC between a coupled body (poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer: F-g1-g2-X-g2-g1-F; wherein X represents a coupled residue (Si(Me).sub.2-); number average molecular weight (Mn)=81,000) and an unreacted block copolymer (poly--methylstyrene-polybutadiene block copolymer: F-g1-g2, number average molecular weight (Mn)=41,000), the coupling efficiency was 94% by mass. Furthermore, according to the results of a .sup.1H-NMR analysis, the content of the poly--methylstyrene block in the poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer was 30% by mass, and the amount of 1,4-bonds of the entirety of the polybutadiene blocks (polymer block (B)), that is, block (g1) and block (g2), was 47 mol %.

(54) A Ziegler hydrogenation catalyst formed from nickel octate and triethylaluminum was added in a hydrogen atmosphere to the polymerization reaction solution obtained as described above, and a hydrogenation reaction was carried out for 5 hours at 80 C. at a hydrogen pressure of 0.8 MPa. Thus, a hydrogenation product of the poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer [hereinafter, this is simply referred to as block copolymer (I)-1] was obtained.

(55) The block copolymer (I)-1 thus obtained was analyzed by GPC, and as a result, a main component thereof was a hydrogenation product (coupled body) of a poly--methylstyrene-polybutadiene-poly--methylstyrene triblock copolymer with peak top molecular weight (Mt)=81,000, number average molecular weight (Mn)=78,700, weight average molecular weight (Mw)=79,500, and Mw/Mn=1.01. It was found from the area ratio of UV (254 nm) absorption in GPC that the coupled body was included in an amount of 94% by mass. Furthermore, the hydrogenation ratio of the polybutadiene block composed of block (g1) and block (g2) was found by a .sup.1H-NMR analysis to be 97 mol %.

(56) The melt flow rate at 230 C. under a load of 2.16 kg was 17 g/10 min.

(57) The details of the aromatic vinyl-based block copolymers (a-1) obtained Production Examples 1 to 3 are summarized in Table 1.

(58) TABLE-US-00001 TABLE 1 Aromatic vinyl-based block copolymer (a-1) (1) (2) (3) Kind of polymer block F Poly- Poly(- Poly(- styrene methyl- methyl- styrene) styrene) Content of the kind of 31 30 30 polymer block F (mol %) Kind of polymer block G Poly- Poly- Poly- isoprene butadiene butadiene Hydrogenation ratio of 98 97 97 polymer block G (mol %) Amount of 1,4-bonds of 93 60 47 polymer block G (mol %) Number average molecular 57,600 78,700 78,700 weight (Mn) MFR (230 C., 2.16 kg) 50 5.0 17 (g/10 min)
[Acrylic Polymer (a-2)]

(59) (4) PARAPET GF (trade name, methacrylic resin manufactured by Kuraray Co., Ltd.)

(60) (5) PARAPET G (trade name, methacrylic resin manufactured by Kuraray co., Ltd.)

(61) The melt flow rates of the above-mentioned acrylic polymers (a-2) are presented in Table 2.

(62) TABLE-US-00002 TABLE 2 Acrylic polymer (a-2) (4) (5) MFR (230 C., 3.8 kg) (g/10 min) 15 8.0
[Olefin-Based Polymer Containing Polar Groups (a-3)]

(63) (6) ULTRACENE #680 (trade name, ethylene-vinyl acetate copolymer (EVA resin) manufactured by Tosoh Corp., content of vinyl acetate in the copolymer: 20% by mass)

(64) (7) ELVALOYAC 12024S (trade name, ethylene-methyl acrylate copolymer (EMA resin) manufactured by DuPont-Mitsui Polychemicals Co., Ltd., content of methyl acrylate in the copolymer: 24% by mass)

(65) (8) NUCREL N1525 (trade name, manufactured by DuPont-Mitsui Polychemicals Co., Ltd., ethylene-methacrylic acid copolymer (EMAA resin), content of methacrylic acid in the copolymer: 15% by mass)

(66) The melt flow rates of the olefin-based polymers containing polar groups (a-3) are presented in Table 3.

(67) TABLE-US-00003 TABLE 3 Olefin-based polymer containing polar groups (a-3) (6) (7) (8) Kind EVA resin EMA resin EMAA resin MFR (190 C., 2.16 kg) 160 20 25 (g/10 min) EVA resin: ethylene-vinyl acetate copolymer EMA resin: ethylene-methyl acrylate copolymer EMAA resin: ethylene-methacrylic acid copolymer
[Softening Agent (a-4)]

(68) (9) DIANA PROCESS OIL PW380 (trade name, paraffinic process oil manufactured by Idemitsu Kosan Co., Ltd., dynamic viscosity (40 C.)=386.1 mm.sup.2/s)

(69) TABLE-US-00004 TABLE 4 Softening agent (a-4) (9) Kind Paraffinic process oil
[Acrylic Pressure-Sensitive Adhesive: Acrylic Block Copolymer (b-1)] (for Pressure-Sensitive Adhesive Layer)

(70) As the acrylic block copolymer (b-1), a product obtained by performing living anionic polymerization in toluene in the presence of 1,2-dimethoxyethane and isobutylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum using sec butyllithium as a polymerization initiator, was used.

(71) (10) Acrylic block copolymer

(72) As shown in the following Table 5, a triblock copolymer of methyl methacrylate polymer block (PMMA)-n-butyl acrylate polymer block (PnBA)-methyl methacrylate polymer block (PMMA) having a PMMA content of 20% by mass, a Mw of 81,000, and a molecular weight distribution of 1.15 was used.

(73) (11) Acrylic block copolymer

(74) As shown in the following Table 5, a triblock copolymer of methyl methacrylate polymer block (PMMA)-n-butyl acrylate/2-ethylhexyl acrylate polymer block (P(nBA/2EHA))-methyl methacrylate polymer block (PMMA) having a PMMA content of 20% by mass, a mass ratio of n-butyl acrylate/2-ethylhexyl acrylate of 50/50, a weight average molecular weight of 80,000, and a molecular weight distribution (weight average molecular weight/number average molecular weight) of 1.14 was used.

(75) (12) Acrylic block copolymer

(76) As shown in the following Table 5, a triblock copolymer of methyl methacrylate polymer block (PMMA)-n-butyl acrylate polymer block (PnBA)-methyl methacrylate polymer block (PMMA) having a PMMA content of 20% by mass, a Mw of 160,000, and a molecular weight distribution of 1.18 was used.

(77) The details of the acrylic block copolymers (b-1) are summarized in Table 5.

(78) TABLE-US-00005 TABLE 5 Acrylic pressure-sensitive adhesive: acrylic block copolymer (b-1) (10) (11) (12) Form Triblock Triblock Triblock copolymer copolymer copolymer Polymer block (I-1): PMMA PMMA PMMA 1.sup.st block Polymer block (I-2): PnBA P(nBA/2EHA) PnBA 2.sup.nd block Polymer block (I-1): PMMA PMMA PMMA 3.sup.rd block Mw 81,000 80,000 160,000 Mw/Mn 1.15 1.14 1.20 Copolymerized MMA/nBA = MMA/nBA/ MMA/nBA = components in 20/80 2EHA = 20/80 block copolymer 20/40/40 (mass ratio) Shear viscosity 1.6 1.3 35 characteristics (Ex/Ey) MMA: methyl methacrylate nBA: n-butyl acrylate 2EHA: 2-ethylhexyl acrylate
[Polyolefin-Based Polymer] (for Substrate Layer)

(79) (13) PRIME POLYPRO J715M (trade name, polypropylene resin manufactured by Prime Polymer Co. Ltd., melting point: 160 C., tensile modulus: 1300 MPa)

(80) (14) NOVATEC HF560 (trade name, polyethylene resin manufactured by Japan Polyethylene Corp., melting point: 134 C., tensile modulus: 1050 MPa)

(81) (15) NOVATEC LC600A (trade name, polyethylene resin manufactured by Japan Polyethylene Corp., melting point: 106 C., tensile modulus: 120 MPa)

(82) TABLE-US-00006 TABLE 6 Polyolefin-based polymer (13) (14) (15) Kind PP PE PE Melting point ( C.) 160 134 106 MFR (190 C., 2.16 kg) 7.0 7.0 MFR (230 C., 2.16 kg) 9.0 Tensile modulus at 23 C. (MPa) 1,300 1,050 120 PP: polypropylene resin PE: polyethylene resin

Examples 1 to 11 and Comparative Examples 1 to 8: Production of Thermoplastic Polymer Compositions (16) to (34)

(83) Pellets of thermoplastic polymer compositions were produced using the materials described in the above Tables 1 to 6, by melt kneading the materials at 230 C. at the blending ratios indicated in the following Table 7 using a twin-screw extruder, subsequently extruding the materials, and cutting the products.

Examples 12 to 26 and Comparative Examples 9 to 16: Production of Laminates Composed of Three Layers

(84) Laminates were produced by the method described in the above section <8. Co-extrusion molding processability> using the pellets of thermoplastic polymer compositions obtained by the method described above, and the acrylic block copolymers (b-1) and the polyolefin-based polymers described in Tables 5 and 6. Specimens were collected from the laminates thus obtained, and the co-extrusion molding processability, delamination resistance, and the 180 peeling strength against acrylic resin plates were evaluated. The results are presented in Table 8 and Table 9.

(85) TABLE-US-00007 TABLE 7 Example 1 2 3 4 5 6 7 8 9 10 11 Thermoplastic resin (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) composition Aromatic vinyl-based (1) 35 25 10 block copolymer (a-1) (2) 35 33 35 25 10 35 35 (3) 35 Acrylic resin (a-2) (4) 35 25 40 35 35 33 25 40 35 35 (5) 35 Olefin-based polymer (6) 30 50 50 30 30 29 30 50 50 containing polar (7) 30 groups (a-3) (8) 30 Polyolefin-based (13) polymer (not containing polar groups) Softening agent (a-4) (9) 5 Comparative Example 1 2 3 4 5 6 7 8 Thermoplastic resin (27) (28) (29) (30) (31) (32) (33) (34) composition Aromatic vinyl-based (1) 50 block copolymer (a-1) (2) 45 50 35 50 (3) Acrylic resin (a-2) (4) 45 50 50 35 50 (5) Olefin-based polymer (6) 10 50 50 100 containing polar (7) 100 groups (a-3) (8) Polyolefin-based (13) 30 polymer (not containing polar groups) Softening agent (a-4) (9)

(86) TABLE-US-00008 TABLE 8 Example 12 13 14 15 16 17 18 19 Laminate Substrate layer (C) Polyolefin-based (13) (13) (13) (13) (13) (13) (14) (13) polymer Layer (A) Thermoplastic resin (16) (17) (18) (19) (20) (19) (19) (21) composition Pressure-sensitive Acrylic pressure- (10) (10) (10) (10) (10) (11) (10) (10) adhesive layer (B) sensitive adhesive (Ea/Eb) of thermoplastic resin composition 8 6 7 7 6 7 7 6 Absolute value of difference between (Ea/Eb) of 6 4 5 5 4 6 5 4 thermoplastic resin composition and (Ex/Ey) of acrylic pressure-sensitive adhesive Evaluation Co-extrusion Surging + + + + + ++ + + processability Surface smoothness ++ ++ ++ ++ ++ ++ ++ ++ Withdrawability ++ ++ ++ ++ ++ + ++ ++ Delamination resistance between substrate layer ++ ++ + ++ ++ ++ ++ ++ (C) and layer (A) Delamination resistance between layer (A) and + + + ++ ++ ++ ++ ++ pressure-sensitive adhesive layer (B) 180 peeling strength against PMMA plate 9 9 9 9 9 8 9 9 (N/25 mm) Example 20 21 22 23 24 25 26 Laminate Substrate layer (C) Polyolefin-based (13) (13) (13) (13) (13) (13) (15) polymer Layer (A) Thermoplastic resin (22) (23) (24) (25) (26) (19) (19) composition Pressure-sensitive Acrylic pressure- (10) (10) (10) (10) (10) (12) (10) adhesive layer (B) sensitive adhesive (Ea/Eb) of thermoplastic resin composition 9 6 5 9 9 7 7 Absolute value of difference between (Ea/Eb) of 7 4 3 7 7 28 5 thermoplastic resin composition and (Ex/Ey) of acrylic pressure-sensitive adhesive Evaluation Co-extrusion Surging + + + + + + + processability Surface smoothness + ++ ++ ++ ++ + ++ Withdrawability ++ ++ ++ ++ ++ + + Delamination resistance between substrate layer ++ ++ + + ++ ++ + (C) and layer (A) Delamination resistance between layer (A) and ++ ++ ++ ++ ++ ++ + pressure-sensitive adhesive layer (B) 180 peeling strength against PMMA plate 9 9 9 9 9 7 6 (N/25 mm)

(87) TABLE-US-00009 TABLE 9 Comparative Example 9 10 11 12 13 14 15 16 Laminate Substrate layer (C) Polyolefin-based (13) (13) (13) (13) (13) (13) (13) (13) polymer Layer (A) Thermoplastic (27) (28) (29) (30) (31) (32) (33) (34) resin composition Pressure-sensitive Acrylic pressure- (10) (10) (10) (10) (10) (10) (10) (10) adhesive layer (B) sensitive adhesive (Ea/Eb) of thermoplastic resin 14 22 15 9 8 7 2 4 composition Absolute value of difference between 12 20 13 7 6 6 0.4 2 (Ea/Eb) of thermoplastic resin composition and (Ex/Ey) of acrylic pressure-sensitive adhesive Evaluation Co-extrusion Surging + + + + + processability Surface ++ ++ ++ smoothness Withdrawability ++ ++ ++ + + Delamination resistance between Not Not Not ++ + + ++ ++ substrate layer (C) and layer (A) evaluable evaluable evaluable Delamination resistance between layer Not Not Not (A) and pressure-sensitive adhesive evaluable evaluable evaluable layer (B) 180 peeling strength against PMMA Not Not Not Not Not Not Not Not plate mea- mea- mea- mea- mea- mea- mea- mea- (N/25 mm) surable surable surable surable surable surable surable surable

(88) The thermoplastic polymer compositions (16) to (26) produced in Examples 1 to 11 had melt viscosities that were advantageous for co-extrusion processing, and the laminates of Examples 12 to 26, each of which included a layer formed from the respective thermoplastic polymer compositions (A) between a pressure-sensitive adhesive layer (B) and a substrate layer (C), had an excellent balance between the co-extrusion molding processability, delamination resistance, and the 180 peeling strength against an acrylic resin plate.

(89) On the other hand, the thermoplastic polymer compositions (27) to (29) produced in Comparative Examples 1 to 3 had high shear velocity dependency, and the laminates of Comparative Examples 9 to 11, each of which included a layer formed from the respective thermoplastic polymer compositions, had poor co-extrusion molding processability. Furthermore, the thermoplastic polymer compositions (30) to (34) produced in Comparative Examples 4 to 8 had low shear velocity dependency, but had low affinity with acrylic pressure-sensitive adhesives. In the laminates of Comparative Examples 12 to 16, each of which had a layer formed from the respective thermoplastic polymer compositions, delamination occurred between the layer formed from a thermoplastic polymer composition and the pressure-sensitive adhesive layer containing an acrylic pressure-sensitive adhesive.

INDUSTRIAL APPLICABILITY

(90) The laminate of the invention can be suitably used as protective films, pressure-sensitive adhesive tapes, labels and the like that are used in the fields of optics, automobile industry, electronics, medicine, construction, environment, and the like.