Polymer composition, method for producing polymer composition, and aqueous dispersion composition

Abstract

The present invention is a polymer composition containing a modified polypropylene modified with at least one type selected from the group consisting of unsaturated carboxylic acids and derivatives thereof, the difference (X1-X2) between the content (X1) of the unsaturated carboxylic acid and / or the derivative thereof in the polymer composition before acetone extraction and the content (X2) of the unsaturated carboxylic acid and / or the derivative thereof in the polymer composition after acetone extraction is 0.01-0.5 mass%; the content (X2) of the unsaturated carboxylic acid and / or the derivative thereof in the polymer composition after acetone extraction is 0.7-1.8 mass%, and the MFR measured according to JIS K7210 under the conditions of 180 DEG C, a load of 2.16 kg, and a 1 mm orifice is 1-40 g / 10 minutes.

Description

Technical Field

[0001] The present invention relates to a polymer composition capable of realizing an adhesive having excellent adhesiveness and heat resistance, and a method for producing the same.

[0002] In addition, the present invention relates to an adhesive comprising the polymer composition, a polymer composition for aqueous dispersion comprising the polymer composition, and an aqueous dispersion composition comprising the polymer composition. Background Art

[0003] In the field of building materials or automobiles, parts are used that are formed by bonding low-polar adherends such as polypropylene or ABS to metal or high-polar adherends using adhesives. For the adhesives used here, a solvent-free type that does not use an organic solvent is required based on recent environmental protection considerations.

[0004] As a solvent-free adhesive capable of adhering to these adherends, there is known a solvent-free adhesive composed of an aqueous dispersion composition containing an acid-modified polyolefin (Patent Documents 1 and 2).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2015-117382

[0008] Patent Document 2: Japanese Patent Application Publication No. 2015-163688 Summary of the invention

[0009] Adhesives for use in building materials and automobiles are in need of adhesives with improved adhesiveness and heat resistance. However, from the viewpoint of achieving both adhesiveness and heat resistance, conventional adhesives containing acid-modified polyolefins have room for improvement.

[0010] An object of the present invention is to provide a polymer composition capable of realizing an adhesive having excellent adhesiveness and heat resistance, and a method for producing the same.

[0011] Another object of the present invention is to provide an adhesive comprising the polymer composition, a polymer composition for an aqueous dispersion comprising the polymer composition, and an aqueous dispersion composition comprising the polymer composition.

[0012] The present inventors have found that, in a polymer composition containing unsaturated carboxylic acid-modified polypropylene and an unsaturated carboxylic acid, by setting the modification rate of the unsaturated carboxylic acid-modified polypropylene, the content rate of the unsaturated carboxylic acid, and the MFR to specific numerical ranges, a polymer composition capable of realizing an adhesive having excellent adhesiveness and heat resistance can be obtained.

[0013] The present invention has the following features.

[0014] [1] A polymer composition comprising a modified polypropylene modified with at least one selected from unsaturated carboxylic acids and their derivatives, and

[0015] The difference (X1-X2) between the mass ratio X1 (mass %) defined below and the mass ratio X2 (mass %) defined below is 0.01 mass % to 0.5 mass %,

[0016] The following mass ratio X2 (mass %) is 0.7 mass % to 1.8 mass %,

[0017] The MFR of the polymer composition measured under the conditions of 180° C., a load of 2.16 kg and an orifice of 1 mm in accordance with JIS K7210 is 1 g / 10 min to 40 g / 10 min.

[0018] Mass ratio X1 (mass %): The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes. The obtained disc was used as a measurement sample. The infrared absorption spectrometry was performed according to the wavelength of 1900 to 1600 cm -1 The measured value of carbonyl characteristic absorption of the measured sample, the mass ratio (mass %) of the sum of the mass of the unsaturated carboxylic acid and / or its derivative graft-polymerized with the polypropylene in the measured sample and the mass of the unsaturated carboxylic acid and / or its derivative existing as a monomer in the measured sample to the measured sample calculated using the calibration curve

[0019] Mass ratio X2 (mass %): The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes. The obtained disc was placed in a Soxhlet extractor and refluxed with acetone at 80° C. for 1 hour. The disc was then dried at 80° C. for 2 hours as a sample for infrared absorption spectrum measurement. The infrared absorption spectrometry was performed based on the wavelengths of 1900 to 1600 cm -1 The mass ratio (mass %) of the unsaturated carboxylic acid and / or its derivative graft-polymerized with polypropylene in the measurement sample calculated using the calibration curve is:

[0020] [2] The polymer composition according to [1], wherein the MFR measured under the conditions of 180°C, 2.16 kg load, and 1 mm orifice according to JIS K7210 is 5 g / 10 min to 40 g / 10 min.

[0021] [3] The polymer composition according to [1] or [2], which is a polymer composition for an aqueous dispersion.

[0022] [4] A method for producing a polymer composition according to any one of [1] to [3], comprising the step of reacting a raw material polypropylene comprising a polypropylene (a) having a bending elastic modulus of 100 MPa to 2000 MPa with an unsaturated carboxylic acid and / or its derivative (b) in the presence of a peroxyester (c1) and a dialkyl peroxide (c2).

[0023] [5] The method for producing a polymer composition according to [4], wherein the peroxyester (c1) is tert-butyl peroxyisopropyl carbonate.

[0024] [6] The method for producing a polymer composition according to [4] or [5], wherein the dialkyl peroxide (c2) is di-tert-butyl peroxide.

[0025] [7] The method for producing a polymer composition according to any one of [4] to [6], wherein the raw material polypropylene further comprises a polypropylene (d) having a flexural modulus of less than 100 MPa or a viscosity at 190°C of 100 cP to 3000 cP.

[0026] [8] The method for producing a polymer composition according to any one of [4] to [7], wherein the content of the polypropylene (a) is 50% by mass to 100% by mass relative to 100% by mass of the raw material polypropylene.

[0027] [9] The method for producing a polymer composition according to [7] or [8], wherein the content of the polypropylene (d) is 1% by mass to 50% by mass relative to 100% by mass of the raw material polypropylene.

[0028]

[10] An adhesive comprising the polymer composition according to any one of [1] to [3].

[0029]

[11] An aqueous dispersion composition comprising the polymer composition according to any one of [1] to [3], a surfactant, and water.

[0030] According to the polymer composition of the present invention and the aqueous dispersion composition containing the polymer composition, an adhesive having excellent adhesiveness and heat resistance can be provided. DETAILED DESCRIPTION

[0031] The embodiments of the present invention are described in detail below. The present invention is not limited to the following description, and can be implemented with arbitrary changes without departing from the gist of the present invention.

[0032] In this specification, when "to" is used and a numerical value or a physical property value is sandwiched before and after it to express, it is used so that the values ​​before and after it are included.

[0033] Hereinafter, the monomer units contained in the copolymer may be simply referred to as "units". For example, a monomer unit based on propylene may be referred to as a "propylene unit", and a monomer unit based on ethylene and a monomer unit based on α-olefin may be referred to as an "ethylene unit" and an "α-olefin unit", respectively.

[0034] In the present invention, the MFR (melt flow rate) of the polymer composition is measured in accordance with JIS K7210 under the conditions of 180° C., a load of 2.16 kg, and an orifice of 1 mm.

[0035] The MFR (melt flow rate) of polypropylene was measured in accordance with JIS K7210 under the conditions of 230° C., a load of 2.16 kg, and an orifice of 2 mm.

[0036] In the present invention, the polymer composition and the flexural modulus of polypropylene are values ​​measured in accordance with JIS K 7171.

[0037] The viscosity of polypropylene at 190°C is a viscosity measured at 190°C by a method in accordance with JIS K 2283.

[0038] The density of polypropylene is a value measured in accordance with JIS K7112.

[0039] [Polymer composition]

[0040] The polymer composition of the present invention is characterized in that it contains a modified polypropylene modified with at least one selected from unsaturated carboxylic acids and derivatives thereof (hereinafter sometimes referred to as "the modified polypropylene of the present invention"), and

[0041] The difference (X1-X2) between the mass ratio X1 (mass %) defined below and the mass ratio X2 (mass %) defined below is 0.01 mass % to 0.5 mass %,

[0042] The following mass ratio X2 (mass %) is 0.7 mass % to 1.8 mass %,

[0043] The MFR of the polymer composition measured under the conditions of 180° C., a load of 2.16 kg and an orifice of 1 mm in accordance with JIS K7210 is 1 g / 10 min to 40 g / 10 min.

[0044] Mass ratio X1 (mass %): The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes. The obtained disc was used as a measurement sample. The infrared absorption spectrometry was performed according to the wavelength of 1900 to 1600 cm -1The measured value of carbonyl characteristic absorption of the measured sample, the mass ratio (mass %) of the total of the unsaturated carboxylic acid and / or its derivatives graft-polymerized with polypropylene in the measured sample and the unsaturated carboxylic acid and / or its derivatives existing as monomers in the measured sample relative to the mass of the measured sample calculated using the calibration curve

[0045] Mass ratio X2 (mass %): The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes. The obtained disc was placed in a Soxhlet extractor and refluxed with acetone at 80° C. for 1 hour. The disc was then dried at 80° C. for 2 hours as a sample for infrared absorption spectrum measurement. The infrared absorption spectrometry was performed based on the wavelengths of 1900 to 1600 cm -1 The mass ratio (mass %) of the unsaturated carboxylic acid and / or its derivative graft-polymerized with polypropylene in the measurement sample calculated using the calibration curve is:

[0046] Hereinafter, the mass ratio X1 (mass %) may be referred to as “the content rate (X1) of the unsaturated carboxylic acid and / or its derivatives in the polymer composition before acetone extraction”, and the mass ratio X2 (mass %) may be referred to as “the content rate (X2) of the unsaturated carboxylic acid and / or its derivatives in the polymer composition after acetone extraction”.

[0047] The polymer composition of the present invention is called a "polymer composition" because it contains modified polypropylene modified with an unsaturated carboxylic acid and / or its derivatives, and unsaturated carboxylic acids and / or its derivatives that are not graft-polymerized with the modified polypropylene after the modification treatment of the raw material polypropylene as described below and exist as monomers, but is also called "modified polypropylene" in industry.

[0048] The polymer composition of the present invention is preferably produced according to the method for producing a polymer composition of the present invention, by reacting a raw material polypropylene containing a polypropylene (a) having a flexural elastic modulus of 100 MPa to 2000 MPa with an unsaturated carboxylic acid and / or its derivative (b) in the presence of a peroxyester (c1) and a dialkyl peroxide (c2).

[0049] The polymer composition of the present invention can be used as an adhesive component of an aqueous dispersion composition of a water-based adhesive.

[0050] [Mass ratio X1 (mass %) and mass ratio X2 (mass %) of polymer composition]

[0051] <Mass ratio X1 (mass %)>

[0052] The content rate (X1) of the unsaturated carboxylic acid and / or its derivative in the polymer composition before acetone extraction, ie, the mass ratio X1 (mass %), when the polymer composition is 100 mass % is a value measured as follows.

[0053] The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes to obtain a disc. The disc was used as a sample for infrared absorption spectrum measurement. The content of carboxylic acid and / or its derivatives was determined based on the absorption characteristic of carboxylic acid and / or its derivatives using infrared absorption spectroscopy. Specifically, the content of carboxylic acid and / or its derivatives was determined by measuring the absorption of 1900 to 1600 cm -1 The value obtained in the above manner is defined as the content (X1) of the unsaturated carboxylic acid and / or its derivative in the polymer composition before acetone extraction, i.e., the mass ratio X1 (mass %), when the polymer composition is defined as 100 mass %.

[0054] <Mass ratio X2 (mass %)>

[0055] The content rate (X2) of the unsaturated carboxylic acid and / or its derivative in the polymer composition after acetone extraction, ie, the mass ratio X2 (mass %), when the polymer composition is 100 mass % is a value measured as follows.

[0056] The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes to obtain a disc. The disc was placed in a Soxhlet extractor and subjected to acetone reflux at 80° C. for 1 hour. Here, the acetone extraction was performed for the purpose of removing unsaturated carboxylic acid and / or its derivatives which existed independently in the polymer composition as reaction residues without graft polymerization with polypropylene.

[0057] Thereafter, the disc was dried at 80°C for 2 hours using a heating dryer. The dried disc was used as a sample for infrared absorption spectrum measurement, and the content of carboxylic acid and / or its derivatives was determined based on the absorption characteristic of carboxylic acid and / or its derivatives using infrared absorption spectroscopy. Specifically, the content of carboxylic acid and / or its derivatives was determined by measuring the absorption of 1900 to 1600 cm -1 The value obtained in the above manner is defined as the content rate (X2) of the unsaturated carboxylic acid and / or its derivative in the polymer composition after acetone extraction, i.e., the mass ratio X2 (mass %), when the polymer composition is defined as 100 mass %.

[0058] The mass ratio X1 (mass %) refers to the content of the unsaturated carboxylic acid and / or its derivative graft-polymerized to the modified polypropylene contained in the polymer composition and the content of the unsaturated carboxylic acid and / or its derivative present as a monomer in the polymer composition as a reaction residue.

[0059] On the other hand, the mass ratio X2 (mass %) refers to the content ratio of the unsaturated carboxylic acid and / or its derivative graft-polymerized to the modified polypropylene contained in the polymer composition.

[0060] Therefore, the difference (X1-X2) between the mass proportion X1 (mass %) and the mass proportion X2 (mass %) of the polymer composition (100 mass %) means the content of the unsaturated carboxylic acid and / or its derivative existing as a monomer in the polymer composition as a reaction residue.

[0061] The mass ratio X2 (mass %), that is, the content of the unsaturated carboxylic acid and / or its derivative graft polymerized to the modified polypropylene contained in the polymer composition, can also be confirmed by the following NMR spectrum measurement.

[0062] 25 mg of the sample of the methyl esterified polymer composition was weighed into an NMR sample tube with an outer diameter of 5 mm, and 0.52 mL of deuterated o-dichlorobenzene (ODCB-d4) was added and dissolved at 130°C. Using an AVANCE NEO 600 spectrometer manufactured by Bruker, the 1 H-NMR spectroscopy was used to determine the methyl ester of the acid-modified polyolefin in the polymer composition. 1 H-NMR. Furthermore, according to the acid-modified polyolefin in the polymer composition before methyl esterification 1 H-NMR, confirmed in methyl ester 1 The area of ​​the peak derived from impurities superimposed on the peak position of the methyl ester in H-NMR. The peak area of ​​the methyl ester can be obtained by subtracting the peak area derived from the impurities from the peak area of ​​the methyl ester, and the content rate of the unsaturated carboxylic acid and / or its derivative graft polymerized with the modified polypropylene in the polymer composition, i.e., X2, can be calculated from the ratio of the mass of the acid-modified group derived therefrom to the mass of the acid-modified polyolefin in the polymer composition before methyl esterification.

[0063] <Mass ratio X1 (mass %)>

[0064] The polymer composition of the present invention preferably has a content (X1) of the unsaturated carboxylic acid and / or its derivative in the polymer composition before acetone extraction of 0.7 to 2.3 mass % based on 100 mass % of the polymer composition.

[0065] From the viewpoint of heat resistance, the upper limit of the mass ratio X1 (mass %) is preferably 2.2 mass % or less, more preferably 2.1 mass % or less.

[0066] <Mass ratio X2 (mass %)>

[0067] The content rate (X2) of the unsaturated carboxylic acid and / or its derivative in the polymer composition after acetone extraction, i.e., the mass ratio X2 (mass %), is 0.7 to 1.8 mass % based on 100 mass % of the polymer composition of the present invention.

[0068] By setting the lower limit of the mass ratio X2 (mass %) to 0.7 mass % or more, the content of the unsaturated carboxylic acid and / or its derivative graft-polymerized with the modified polypropylene is high, the adhesion to the adherend is effectively exhibited, and the dispersibility in the aqueous solvent is improved. From this viewpoint, the lower limit of the mass ratio X2 (mass %) is preferably 0.8 mass % or more, and more preferably 0.9 mass % or more.

[0069] On the other hand, by setting the upper limit of the mass ratio X2 (mass %) to 1.8 mass % or less, excessive reaction to the adherend can be suppressed. From this viewpoint, the upper limit of the mass ratio X2 (mass %) is preferably 1.7 mass % or less, and more preferably 1.6 mass % or less.

[0070] The mass ratio X2 (mass %) can be controlled by the amount of the unsaturated carboxylic acid and / or its derivative (b) added during the modification treatment of the raw material polypropylene described below, and the type or amount of the radical generator used.

[0071] <Difference (X1-X2) between mass ratio X1 (mass %) and mass ratio X2 (mass %)>

[0072] The difference between the content rate (X1) of the unsaturated carboxylic acid and / or its derivatives in the polymer composition before acetone extraction, i.e., the mass ratio X1 (mass %), and the content rate (X2) of the unsaturated carboxylic acid and / or its derivatives in the polymer composition after acetone extraction, i.e., the mass ratio X2 (mass %), when the polymer composition of the present invention is set to 100 mass % (hereinafter sometimes referred to as "the content rate of the unsaturated carboxylic acid and / or its derivatives existing as a monomer") (X1-X2) is 0.01 mass % to 0.5 mass %.

[0073] By setting the upper limit of the content rate (X1-X2) of the unsaturated carboxylic acid and / or its derivatives present as monomers to 0.5 mass % or less, it is possible to suppress the adhesion hindrance caused by the unsaturated carboxylic acid and / or its derivatives present as monomers, and also to reduce the odor. From this viewpoint, the upper limit of the content rate (X1-X2) of the unsaturated carboxylic acid and / or its derivatives present as monomers is usually 0.5 mass % or less, preferably 0.4 mass % or less.

[0074] On the other hand, the lower limit of the content rate (X1-X2) of the unsaturated carboxylic acid and / or its derivative existing as a monomer is not particularly limited, but is usually 0.01 mass % or more.

[0075] The content (X1-X2) of the unsaturated carboxylic acid and / or its derivative (b) present as a monomer can be controlled by the amount of the unsaturated carboxylic acid and / or its derivative (b) added during the modification treatment of the raw material polypropylene described below and the type or amount of the free radical generator used.

[0076] [MFR]

[0077] The polymer composition of the present invention has an MFR of 1 g / 10 min to 40 g / 10 min measured under the conditions of 180° C., a load of 2.16 kg and an orifice of 1 mm in accordance with JIS K7210.

[0078] By setting the lower limit of MFR to 1 g / 10 min or more, the fluidity required as an adhesive can be ensured. From this viewpoint, the lower limit of MFR of the polymer composition of the present invention measured under the above-mentioned measurement conditions is preferably 5 g / 10 min or more.

[0079] On the other hand, by making the upper limit of the MFR measured under the above-mentioned measurement conditions of the polymer composition 40 g / 10 minutes or less, the heat resistance required as an adhesive can be ensured. From this viewpoint, the upper limit of the MFR measured under the above-mentioned measurement conditions of the polymer composition of the present invention is preferably 35 g / 10 minutes or less.

[0080] [Modified polypropylene]

[0081] The modified polypropylene of the present invention is a modified polypropylene obtained by modifying polypropylene with at least one selected from unsaturated carboxylic acids and derivatives thereof.

[0082] The modified polypropylene of the present invention is produced by subjecting the raw material polypropylene described below to a modification treatment with an unsaturated carboxylic acid and / or a derivative thereof (b) in the presence of a radical generator.

[0083] The polypropylene for modification (referred to as "raw material polypropylene" in the present invention) is not particularly limited, and a homopolymer of propylene or a copolymer of propylene and other monomers can be used. Other monomers that can constitute the copolymer include α-olefins having 3 to 20 carbon atoms such as ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, 1-hexene, 4-methyl-1-hexene, 1-heptene, 1-octene, 1-decene, or 1-octadecene. These other monomers may be used alone or in combination of two or more.

[0084] Specific examples of the polypropylene to be modified include propylene-based copolymers such as propylene·ethylene random copolymers, propylene·butene random copolymers, propylene·ethylene·hexene random copolymers, propylene·ethylene·octene random copolymers, propylene·butene·hexene random copolymers, propylene·butene·octene random copolymers, propylene·hexene·octene random copolymers, or propylene·ethylene block copolymers.

[0085] Among them, from the viewpoint of achieving both heat resistance and adhesiveness, the raw material polypropylene preferably contains a polypropylene having a bending modulus of 100 MPa to 2000 MPa (hereinafter sometimes referred to as polypropylene (a)), and more preferably contains polypropylene (a) and a polypropylene having a bending modulus of less than 100 MPa (hereinafter sometimes referred to as polypropylene (d)). As polypropylene (d), it is further preferred to contain a polypropylene having a bending modulus of 1 MPa or more and less than 100 MPa.

[0086] The polypropylene (a) and the polypropylene (d) may be the same type of polypropylene or different types of polypropylene as long as their respective flexural moduli are within the above range.

[0087] <Polypropylene (a) having a flexural modulus of 100 MPa to 2000 MPa>

[0088] (Flexural modulus)

[0089] The bending modulus of polypropylene (a) is 100 MPa to 2000 MPa. By making the lower limit of the bending modulus of polypropylene (a) above 100 MPa, the mechanical strength and heat resistance of the obtained adhesive can be improved. From this viewpoint, the lower limit of the bending modulus of polypropylene (a) is preferably above 200 MPa, more preferably above 300 MPa.

[0090] On the other hand, by setting the upper limit of the flexural modulus of the polypropylene (a) to 2000 MPa or less, the impact resistance can be improved. From this viewpoint, the upper limit of the flexural modulus of the polypropylene (a) is preferably 1800 MPa or less, more preferably 1500 MPa or less.

[0091] The flexural modulus of polypropylene (a) can be controlled by the type or content of other monomers other than propylene in the propylene copolymer. For example, in the case of propylene-ethylene copolymer, the flexural modulus tends to decrease as the content of ethylene units increases.

[0092] (MFR)

[0093] The MFR of the polypropylene (a) measured at 230°C and a load of 2.16 kg in accordance with JIS K7210 is preferably 10 to 50 g / 10 minutes.

[0094] By setting the lower limit of the MFR of the polypropylene (a) to 10 g / 10 min or more, the fluidity of the modified polypropylene of the present invention can be maintained within a desired range. From this viewpoint, the lower limit of the MFR of the polypropylene (a) is more preferably 20 g / 10 min or more.

[0095] On the other hand, by setting the upper limit of the MFR of the polypropylene (a) measured under the above measurement conditions to 50 g / 10 min or less, the mechanical strength required as an adhesive can be maintained. From this viewpoint, the upper limit of the MFR of the polypropylene (a) is more preferably 40 g / 10 min or less.

[0096] When two or more polypropylenes (a) are used, the MFR of the whole polypropylene (a) may be within the above-mentioned numerical range even if a part of the polypropylene (a) deviates from the above-mentioned MFR.

[0097] (density)

[0098] The density of polypropylene (a) is preferably 0.890 g / cm 3 ~0.910g / cm 3 .

[0099] By setting the lower limit of the density of the polypropylene (a) to 0.890 g / cm 3 From this viewpoint, the lower limit of the density of the polypropylene (a) is more preferably 0.895 g / cm 3 above.

[0100] On the other hand, by setting the upper limit of the density of the polypropylene (a) to 0.910 g / cm 3 From this viewpoint, the upper limit of the density of the polypropylene (a) is more preferably 0.905 g / cm 3 the following.

[0101] When two or more polypropylenes (a) are used, the density of the whole polypropylene (a) may be within the above-mentioned range even if the density of a part of the polypropylene (a) deviates from the above-mentioned range.

[0102] (Commercially available product of polypropylene (a))

[0103] As the polypropylene (a), a commercially available product can be used. As a commercially available product of the polypropylene (a), for example, "WINTEC (registered trademark)" manufactured by Japan Polypropylene Co., Ltd. can be cited.

[0104] <Polypropylene (d) having a flexural modulus of less than 100 MPa or a viscosity at 190°C of 100 cP to 3000 cP>

[0105] (Flexural modulus and viscosity)

[0106] The flexural modulus of the polypropylene (d) is less than 100 MPa or the viscosity at 190° C. is 100 cP to 3000 cP.

[0107] The lower limit of the flexural modulus of the polypropylene (d) is not particularly limited, but 1 MPa or more tends to easily impart flexibility suitable for adhesives. From this viewpoint, the lower limit of the flexural modulus of the polypropylene (d) is more preferably 5 MPa or more.

[0108] On the other hand, by making the upper limit of the bending modulus of polypropylene (d) less than 100 MPa, it is possible to give the adhesive a minimum degree of flexibility when used in combination with polypropylene (a). From this viewpoint, the upper limit of the bending modulus of polypropylene (d) is preferably 90 MPa or less, more preferably 80 MPa or less.

[0109] Even when the polypropylene (d) is soft and the flexural modulus cannot be measured, any material having a viscosity of 100 to 3000 cP at 190° C. can be used as the polypropylene (d).

[0110] The flexural modulus and viscosity of the polypropylene (d) can be controlled by the type or content of monomers other than propylene in the propylene-based copolymer, similarly to the flexural modulus of the polypropylene (a).

[0111] (MFR)

[0112] The MFR of the polypropylene (d) measured at 230°C and a load of 2.16 kg in accordance with JIS K7210 is preferably 1 g / 10 min to 30 g / 10 min.

[0113] When the lower limit of the MFR of the polypropylene (d) is 1 g / 10 min or more, the fluidity required for the adhesive can be ensured. From this viewpoint, the lower limit of the MFR of the polypropylene (d) is more preferably 2 g / 10 min or more.

[0114] On the other hand, the upper limit of the MFR of the polypropylene (d) measured under the above measurement conditions is not particularly limited, but heat resistance can be maintained if it is 30 g / 10 min or less. From this viewpoint, the upper limit of the MFR of the polypropylene (d) is more preferably 20 g / 10 min or less.

[0115] When two or more types of polypropylene (d) are used, the MFR of the whole polypropylene (d) may be within the above-mentioned numerical range even if a part of the polypropylene (d) deviates from the above-mentioned MFR.

[0116] (density)

[0117] The density of polypropylene (d) is preferably 0.855 g / cm 3 ~0.885g / cm 3 .

[0118] If the lower limit of the density of polypropylene (d) is 0.855 g / cm 3 From this viewpoint, the lower limit of the density of the polypropylene (d) is more preferably 0.860 g / cm 3 above.

[0119] On the other hand, if the upper limit of the density of the polypropylene (d) is 0.885 g / cm 3 From this viewpoint, the upper limit of the density of the polypropylene (d) is more preferably 0.880 g / cm 3 the following.

[0120] When two or more types of polypropylene (d) are used, the density of the whole polypropylene (d) may be within the above-mentioned numerical range even if the density of a part of the polypropylene (d) deviates from the above-mentioned range.

[0121] (Commercially available product of polypropylene (d))

[0122] As the polypropylene (d), a commercially available product can be used. As a commercially available product of the polypropylene (d), for example, "Vistamaxx (registered trademark)" manufactured by EXXONMobil Corporation can be cited.

[0123] <Content ratio of polypropylene (a) and polypropylene (d)>

[0124] The raw material polypropylene of the modified polypropylene may contain only the polypropylene (a) or may contain the polypropylene (a) and the polypropylene (d).

[0125] The content of the polypropylene (a) relative to 100% by mass of the raw material polypropylene is preferably 50 to 100% by mass, more preferably 50 to 99% by mass, more preferably 55 to 95% by mass, further preferably 60 to 90% by mass.

[0126] If the content of polypropylene (a) in the raw material polypropylene is below the above lower limit, the mechanical strength and heat resistance of the obtained adhesive can be improved. On the other hand, if the content of polypropylene (a) is below the above upper limit, the content of polypropylene (d) can be ensured, and the obtained adhesive can be given flexibility.

[0127] When the raw material polypropylene contains polypropylene (a) and polypropylene (d), the content of polypropylene (d) relative to 100% by mass of the raw material polypropylene is preferably 1% to 50% by mass, more preferably 5% to 45% by mass, and more preferably 10% to 40% by mass.

[0128] If the content of polypropylene (d) in the raw material polypropylene is above the above lower limit, the obtained adhesive can be given good flexibility. On the other hand, if the content of polypropylene (d) is below the above upper limit, the content of polypropylene (a) can be ensured, and the mechanical strength and heat resistance of the obtained adhesive can be good.

[0129] <Unsaturated carboxylic acid and / or its derivative (b)>

[0130] As the unsaturated carboxylic acid used for modifying the raw material polypropylene, α,β-ethylenic unsaturated carboxylic acid is preferred, for example, acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, fumaric acid, tetrahydrofumaric acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid. As the derivatives of unsaturated carboxylic acid, anhydrides and carboxylates of these unsaturated carboxylic acids can be exemplified. The derivatives of unsaturated carboxylic acids can also be derivatives such as acyl halides, amides, and imides of these unsaturated carboxylic acids. Among these derivatives, anhydrides are preferred.

[0131] The unsaturated carboxylic acid and / or its derivative (b) may be used alone or in combination of two or more.

[0132] As the unsaturated carboxylic acid and / or its derivative (b), among these, maleic acid and / or its anhydride is particularly preferred.

[0133] As a modifier for the raw material polypropylene, so-called vinyl silanes such as vinyltrimethoxysilane may be used in combination with these unsaturated carboxylic acids and / or their derivatives (b).

[0134] The amount of unsaturated carboxylic acid and / or its derivative (b) used, i.e., the amount added in the raw material mixture for modification treatment, is usually 0.7 parts by mass or more, preferably 0.9 parts by mass or more, more preferably 1.1 parts by mass or more, and usually 2.5 parts by mass or less, preferably 2.3 parts by mass or less, more preferably 2.1 parts by mass or less, relative to 100 parts by mass of raw material polypropylene. By setting the amount of unsaturated carboxylic acid and / or its derivative (b) added to be above the above lower limit, sufficient modification is easy to carry out. By setting the amount of unsaturated carboxylic acid and / or its derivative (b) added to be below the above upper limit, it is economical and can reduce the content of unsaturated carboxylic acid and / or its derivative (b) that does not contribute to modification contained in the obtained polymer composition, i.e., the content of unsaturated carboxylic acid and / or its derivative present as a monomer (X1-X2).

[0135] <Free Radical Generator>

[0136] The modification of the raw material polypropylene with the unsaturated carboxylic acid and / or its derivative (d) is preferably carried out in the presence of a free radical generator. The free radical generator is used to cause a free radical reaction when the raw material polypropylene is modified with the unsaturated carboxylic acid and / or its derivative (d).

[0137] Examples of the radical generator include peroxyesters (c1), dialkyl peroxides (c2), diacyl peroxides, hydroperoxides, and ketone peroxides.

[0138] Among these, it is preferred to use peroxyesters (c1) and dialkyl peroxides (c2) in combination.

[0139] The peroxyesters (c1) are used to improve the reactivity of the raw material polypropylene with the unsaturated carboxylic acid and / or its derivative (d).

[0140] The dialkyl peroxide (c2) is used for adjustment to improve the MFR of the obtained modified polypropylene, that is, the polymer composition.

[0141] As the peroxyester (c1), tert-butyl peroxyisopropyl carbonate is preferred.

[0142] As the dialkyl peroxide (c2), di-tert-butyl peroxide is preferred.

[0143] As the free radical generator, it is particularly preferred to use tert-butyl peroxyisopropyl carbonate as the peroxyester (c1) and di-tert-butyl peroxide as the dialkyl peroxide (c2).

[0144] The amount of the free radical generator used, i.e., the amount in the raw material mixture for the modification treatment, is generally 0.001 parts by mass or more, preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, generally 5 parts by mass or less, preferably 3 parts by mass or less, more preferably 2 parts by mass or less, relative to 100 parts by mass of the raw material polypropylene. By making the amount of the free radical generator to be above the above lower limit, it is easy to fully cause the modification reaction. By making the amount of the free radical generator to be below the above upper limit, it is possible to suppress the significant reduction in material strength due to the promotion of low molecular weight (viscosity reduction) of polypropylene.

[0145] When the peroxyester (c1) and the dialkyl peroxide (c2) are used together as the free radical generator, 0.2 to 1.0 parts by mass of the peroxyester (c1) and 0.05 to 0.5 parts by mass of the dialkyl peroxide (c2) are blended per 100 parts by mass of the raw material polypropylene, and the total amount thereof preferably reaches the above-mentioned blending amount of the free radical generator.

[0146] <Modification treatment>

[0147] The step of modifying the raw material polypropylene with the unsaturated carboxylic acid and / or its derivative (d) may be performed by any known method. As the modification method, a melt kneading reaction method, a solution reaction method, or a suspension dispersion reaction method may be used. The melt kneading reaction method is generally preferred.

[0148] In the case of utilizing the melt-kneading reaction method, the raw material polypropylene, preferably polypropylene (a), more preferably a mixture of polypropylene (a) and polypropylene (b), unsaturated carboxylic acid and / or its derivative (b), and preferably peroxyesters (c1) and dialkyl peroxides (c2) as free radical generators are uniformly mixed in a prescribed proportion and then melt-kneaded. Mixing can use a Henschel mixer, a ribbon mixer, a V-type blender, etc. Melt-kneading can usually use a single screw or twin screw extruder, a roller, a Banbury mixer, a kneader, a Buchner mixer, etc. Among them, a twin screw extruder is preferred.

[0149] Melt kneading is usually carried out at a temperature of 100°C or higher, preferably 120°C or higher, more preferably 150°C or higher, and usually 300°C or lower, preferably 280°C or lower, more preferably 250°C or lower, so as not to thermally degrade the raw material polypropylene or the produced modified polypropylene.

[0150] 〔Adhesive〕

[0151] The adhesive of the present invention comprises the polymer composition of the present invention and may comprise polymers such as unmodified polypropylene, olefin polymers such as polyethylene, and polar polymers such as polyamide or nylon, within the range that the adhesiveness and heat resistance of the polymer composition of the present invention are not impaired.

[0152] [Aqueous dispersion composition]

[0153] The aqueous dispersion composition of the present invention comprises the polymer composition of the present invention, a surfactant and water as essential components. The aqueous dispersion composition of the present invention may also comprise other polymer dispersants or neutralizers, and other additives.

[0154] [Content ratio of polymer composition]

[0155] The content of the polymer composition of the present invention in the aqueous dispersion composition of the present invention is preferably 40% by mass or more, more preferably 50% by mass or more, and further preferably 60% by mass or more relative to the solid content of the aqueous dispersion composition from the viewpoint of fully obtaining the adhesion and heat resistance obtained by using the modified polypropylene in the polymer composition. On the other hand, the content of the polymer composition of the present invention in the aqueous dispersion composition of the present invention is preferably 95% by mass or less, more preferably 90% by mass or less, and further preferably 85% by mass or less relative to the solid content of the aqueous dispersion composition from the viewpoint of the viscosity or liquid stability of the aqueous dispersion.

[0156] [Surfactant]

[0157] The surfactant used in the aqueous dispersion composition of the present invention is not particularly limited, but a nonionic surfactant is preferably used from the viewpoints of emulsification, safety, and suppression of gelation when various additives are added.

[0158] Examples of nonionic surfactants include polyoxyethylene octyl ether, polyoxyethylene decyl ether, polyoxyethylene dodecyl ether, polyoxyethylene myristyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene isostearyl ether, polyoxyethylene behenyl ether, polyoxyethylene-2-ethylhexyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl ether (synthesized), narrow polyoxyethylene alkyl ether, polyoxyethylene octyldodecyl ether, polyoxyethylene styrenated phenyl ether, polyoxyethylene β-naphthyl ether, polyoxyethylene hydrogenated castor oil ether, polyethylene glycol monoalkyl fatty acid ester, polyethylene glycol fatty acid ester, and polyoxyethylene sorbitan monolaurate. These may be used alone or in combination of two or more.

[0159] Furthermore, in order to obtain a stable aqueous dispersion composition, a cationic surfactant, an anionic surfactant, an amphoteric surfactant, or a reactive surfactant may be used in combination in addition to the above-mentioned nonionic surfactant.

[0160] Examples of the cationic surfactant include higher alkyl monoamine salts such as dodecylamine acetate and stearylamine acetate; alkyl diamine salts such as N-dodecyl-1,3-propylenediamine adipate and N-dodecylpropylenediamine dioleate; and quaternary ammonium salts such as dodecyltrimethylammonium chloride and behenyltrimethylammonium chloride.

[0161] Examples of the anionic surfactant include semi-hardened tallow fatty acid soap sodium salt, stearic acid soap sodium salt, oleic acid soap potassium salt, rosin gum as disproportionated rosin sodium salt, alkenyl succinic acid dipotassium salt, dodecyl sulfate sodium salt, anhydrous sodium bisulfite, polyoxyethylene alkyl (C12, C13) ether sulfate sodium salt, polyoxyethylene dodecyl sulfate ammonium salt, sodium dodecylbenzene sulfonate, and alkylene oxide adducts of higher alcohols (C6-28).

[0162] Examples of the amphoteric surfactant include carboxybetaine-based surfactants, sulfobetaine-based surfactants, phosphate betaine-based surfactants, amidoamino acid-based surfactants, imidazoline-based surfactants, Betaine-based surfactants.

[0163] Examples of the reactive surfactant include compounds having a reactive double bond, such as alkylpropylenephenol polyethylene oxide adducts or sulfate esters thereof, allylalkylphenol polyethylene oxide adducts or sulfate esters thereof, and allyldialkylphenol polyethylene oxide adducts or sulfate esters thereof.

[0164] The surfactant is preferably blended in an amount of 1 to 50% by mass, more preferably 5 to 40% by mass, based on the polymer composition of the present invention.

[0165] When the amount of the surfactant blended is not less than the above lower limit, the polymer composition of the present invention can be dispersed in water stably for a long period of time. When the amount of the surfactant blended is not more than the above upper limit, adhesiveness and heat resistance can be ensured.

[0166] [Polymer dispersant]

[0167] Examples of the polymer dispersant include: polycarboxylic acid polymer dispersants having multiple carboxyl groups in the molecule, polyamine polymer dispersants having multiple amino groups in the molecule, polymer dispersants having multiple amide groups in the molecule, and polymer dispersants containing multiple polycyclic aromatic compounds in the molecule. These may be used alone or in combination of two or more.

[0168] The polymer dispersant is preferably blended in an amount of 0.1 to 10% by mass, more preferably 0.2 to 3% by mass, based on the polymer composition of the present invention.

[0169] When the amount of the polymer dispersant is equal to or greater than the above lower limit, the stability of the polymer composition of the present invention can be further improved. When the amount of the polymer dispersant is equal to or less than the above upper limit, the adhesiveness and heat resistance tend to be easily maintained.

[0170] [Neutralizer]

[0171] Examples of the neutralizing agent include potassium hydroxide, sodium hydroxide, magnesium hydroxide, calcium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, calcium carbonate, calcium bicarbonate, magnesium carbonate, magnesium bicarbonate, monolaurylamine, trimethylamine, dimethylmonoethanolamine, triethanolamine, ethylenediamine, ammonia, morpholine, N-methylmorpholine, and N-ethylmorpholine. These may be used alone or in combination of two or more.

[0172] The neutralizer may be added in an appropriate amount depending on the intended use, and is preferably added in an amount of about 0.1 to 10% by mass based on the total amount of the aqueous dispersion composition.

[0173] [Other additives]

[0174] The aqueous dispersion composition of the present invention may further contain additives commonly used in aqueous dispersions as adhesives within the usual blending amount, such as antioxidants, surface treatment agents, lubricants, slip agents (or texture improvers), antistatic agents (a portion of which overlaps with the above-mentioned surfactants), pH adjusters (a portion of which overlaps with the above-mentioned neutralizers), ultraviolet absorbers, light stabilizers, heat stabilizers, defoamers, anti-aging agents, and leveling agents.

[0175] Examples of the antioxidant include: phenols such as hydroquinone, methoxyhydroquinone, catechol, 2,6-di-tert-butyl-p-cresol (BHT), and 2,2'-methylenebis(4-methyl-6-tert-butylphenol); sulfur-containing compounds such as thiourea, tetramethylthiuram disulfide, dimethyldithiocarbamic acid and its salts, sodium sulfite, sodium thiosulfate, 2-mercaptobenzothiazole and its salts, dilauryl 3,3'-thiodipropionate (DLTDP), and distearyl 3,3'-thiodipropionate (DSTDP); phosphorus-containing compounds such as triphenyl phosphite, triethyl phosphite, sodium phosphite, sodium hypophosphite, triphenyl phosphite (TPP), and triisodecyl phosphite (TDP); and nitrogen-containing compounds such as octylated diphenylamine, N-n-butyl-p-aminophenol, N,N-diisopropyl-p-phenylenediamine, urea, and guanidine.

[0176] Examples of the surface treatment agent include coupling agents such as aminosilane coupling agents, epoxysilane coupling agents, vinylsilane coupling agents, methacrylic silane coupling agents, urea silane coupling agents, borane coupling agents, titanate coupling agents, aluminum coupling agents, chromium coupling agents, and zirconium coupling agents; and colloidal gels such as colloidal silica and colloidal alumina.

[0177] Examples of the lubricant include hydrogenated solids of animal and vegetable oils, paraffin wax, and ester-based synthetic oils.

[0178] Examples of the lubricant (or texture improver) include butyl stearate, tetraethylene pentamine distearate, hydrogenated castor oil, imidazoline fatty acid amide, cationic fatty acid amide, cationic polyethyleneimine polyamide, and bisphenol A poly(oxyethylene) ether diol.

[0179] Examples of the antistatic agent include various surfactants such as anionic surfactants and cationic surfactants.

[0180] Examples of the pH adjuster include acids such as inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid; organic acids such as citric acid, succinic acid, malic acid, and lactic acid; and bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, monoethanolamine, diethanolamine, and triethanolamine.

[0181] Examples of the ultraviolet absorber include benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, cyanoacrylate ultraviolet absorbers, triazine ultraviolet absorbers, cyclic imine ester ultraviolet absorbers, and phenyl salicylate ultraviolet absorbers.

[0182] Examples of the light stabilizer include hindered amine light stabilizers such as 2,2,6,6-tetramethyl-4-piperidinyl stearate and 1,2,2,6,6-pentamethyl-4-piperidinyl stearate.

[0183] [Organic solvents]

[0184] The aqueous dispersion composition of the present invention uses water as a dispersion medium, but may contain a water-soluble organic solvent as necessary.

[0185] In this case, examples of the organic solvent that can be used include alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, sec-pentanol, tert-pentanol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol, and cyclohexanol; ketones such as methyl ethyl ketone, methyl isobutyl ketone, methyl butyl ketone, and cyclohexanone; tetrahydrofuran, dihydrofuran, and cyclohexanone; Ethers such as alkane; esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, 3-methoxybutyl acetate, methyl propionate, ethyl propionate, diethyl carbonate, dimethyl carbonate; glycol derivatives such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, and ethylene glycol ethyl ether acetate. In addition, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 3-methoxy-3-methyl-1-butanol, methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate, 1,2-dimethylglycerol, 1,3-dimethylglycerol, and trimethylglycerol can also be used. These organic solvents can be used alone or in combination of two or more.

[0186] When an organic solvent is used, the amount thereof is not particularly limited and is preferably 0 to 10% by mass relative to the entire aqueous medium.

[0187] [Solid content concentration]

[0188] The solid content concentration of the aqueous dispersion composition of the present invention, i.e., the total concentration of components other than water (which may be an aqueous medium of water and an organic solvent), is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 20% by mass or more, from the viewpoint of ensuring an effective adhesive amount after coating the aqueous dispersion.

[0189] On the other hand, from the viewpoint of liquid stability and coating properties of the aqueous dispersion, the solid content concentration of the aqueous dispersion composition of the present invention is preferably 60% by mass or less, more preferably 55% by mass or less, and even more preferably 50% by mass or less.

[0190] [Average particle size]

[0191] The average particle size of the dispersed particles of the modified polypropylene in the aqueous dispersion composition of the present invention can be arbitrarily adjusted according to the application and is not particularly limited. In applications such as building materials and automobiles, the average particle size of the dispersed particles is preferably 50 to 1000 nm, particularly preferably 100 to 300 nm.

[0192] [pH]

[0193] The pH of the aqueous dispersion composition of the present invention is preferably 6 or more, more preferably 6.5 or more, and is preferably 12 or less, more preferably 11.5 or less, from the viewpoint of liquid stability of the aqueous dispersion.

[0194] [Method for producing aqueous dispersion composition]

[0195] The method for producing the aqueous dispersion composition of the present invention is not particularly limited. The aqueous dispersion composition of the present invention is obtained, for example, by adding the polymer composition of the present invention, a surfactant and an aqueous medium, and a polymer dispersant or a neutralizer as required, to a device such as an autoclave that can be pressurized and has a normal shear force, and heating and stirring to a temperature near or above the softening temperature of the modified polypropylene in the polymer composition of the present invention. The aqueous medium is a liquid with water as the main component, and may also contain the above-mentioned water-soluble organic solvent.

[0196] More specifically, the polymer composition of the present invention, surfactant, polymer dispersant, additives other than other neutralizing agents, and water are added to an autoclave having an emulsification device equipped with a stirrer, a thermometer, and a temperature controller, and heated to about 160 to 200° C. under stirring at 100 to 1500 rpm to finely disperse the polymer composition in a manner to obtain the above-mentioned appropriate dispersed particle size. Thereafter, the mixture is cooled to about room temperature to 80° C., and a neutralizing agent is added as needed to adjust the pH value to the above-mentioned appropriate pH value.

[0197] If necessary, water may be further added to adjust the solid content concentration.

[0198] 〔use〕

[0199] The adhesive and aqueous dispersion composition of the present invention can be particularly effectively used for bonding low-polar adherends such as ABS to metals or high-polar adherends in the fields of building materials or automobiles due to their excellent adhesiveness and heat resistance.

[0200] Example

[0201] The specific embodiment of the present invention is further described in detail using examples below. The present invention is not limited to the following examples as long as it does not exceed its purpose. It should be noted that the values ​​of various manufacturing conditions and evaluation results in the following examples have the meaning of the preferred values ​​as the upper or lower limits in the embodiments of the present invention, and the preferred range can be the range defined by the combination of the values ​​of the above-mentioned upper or lower limits and the values ​​of the following examples or the values ​​of the examples.

[0202] [raw materials]

[0203] In the following Examples and Comparative Examples, the raw materials used to prepare the polymer composition, ie, the modified polypropylene, are as follows.

[0204] <Polypropylene (a)>

[0205] a-1: Propylene-ethylene copolymer

[0206] WINTEC (registered trademark) WMG03 manufactured by Japan Polypropylene Co., Ltd. (flexural modulus: 1250 MPa, MFR (230°C, load 2.16 kg): 30 g / 10 min, density: 0.900 g / cm 3 )

[0207] a-2: Propylene-ethylene copolymer

[0208] WINTEC (registered trademark) WFW4M manufactured by Japan Polypropylene Co., Ltd. (flexural modulus: 900 MPa, MFR (230°C, load 2.16 kg): 7 g / 10 min, density: 0.900 g / cm 3 )

[0209] <Polypropylene (d)>

[0210] d-1: Propylene-ethylene copolymer

[0211] Vistamaxx (registered trademark) 3020FL manufactured by EXXON Mobil (flexural modulus: 47 MPa, MFR (230°C, load 2.16 kg): 2 g / 10 min, density: 0.873 g / cm 3 )

[0212] d-2: Propylene-ethylene copolymer

[0213] Vistamaxx (registered trademark) 6102 manufactured by EXXON Mobil (flexural modulus: 11 MPa, MFR (230°C, load 2.16 kg): 3 g / 10 min, density: 0.862 g / cm 3 )

[0214] d-3: Propylene-ethylene copolymer

[0215] Vistamaxx (registered trademark) 8880 manufactured by EXXON Mobil Corporation (viscosity (190°C): 1200 cP, density: 0.879 g / cm 3 )

[0216] <Unsaturated carboxylic acid and / or its derivative (b)>

[0217] Maleic anhydride (commercially available)

[0218] <Free Radical Generator>

[0219] C-1: tert-Butyl peroxyisopropyl carbonate as peroxyester (c1)

[0220] PERBUTYLI manufactured by Nippon Oils and Fats Co., Ltd.

[0221] C-2: Di-tert-butyl peroxide as dialkyl peroxide (c2)

[0222] PERBUTYLD manufactured by Nippon Oils and Fats Co., Ltd.

[0223] C-3: tert-butyl peroxy 2-ethylhexanoate as peroxyester (c1)

[0224] PERBUTYLO manufactured by Nippon Oils and Fats Co., Ltd.

[0225] [Preparation and evaluation of polymer compositions]

[0226] <Example 1>

[0227] 100 parts by mass of component (a-1), 0.6 parts by mass of component (C-1), 0.2 parts by mass of component (C-2) and 1.5 parts by mass of maleic anhydride of component (b) were dry-blended and mixed, melt-kneaded using a twin-screw extruder (manufactured by The Japan Steel Works, Ltd., TEX25αIII, D=25 mmφ, L / D=52.5) ​​at a set temperature of 230°C, a screw speed of 400 rpm, and an extrusion rate of 20 kg / h, and strand cutting was performed to obtain pellets of modified polypropylene modified with maleic anhydride. The content (X1) of unsaturated carboxylic acid and / or its derivatives before acetone extraction, i.e., mass ratio X1 (mass %), the content (X2) of unsaturated carboxylic acid and / or its derivatives after acetone extraction, i.e., mass ratio X2 (mass %), and MFR (180°C, 2.16 kg) of the obtained modified polypropylene pellets were measured by the above-mentioned method, and the YI, adhesion and heat resistance were evaluated by the following method. The results are shown in Table-1.

[0228] <Examples 2 to 7, Comparative Examples 1 to 6>

[0229] Except having changed the compounding composition as shown in Table-1, the same procedure as in Example 1 was carried out to obtain each modified polypropylene, and the evaluation was carried out in the same manner. The results are shown in Table-1.

[0230] <Evaluation Method>

[0231] (1)YI

[0232] The YI of the modified polypropylene pellets was measured using a commercially available colorimeter (for example, ZE series manufactured by Nippon Denshoku Industries Co., Ltd.) The measurement was performed N=3 times, and the average value was defined as the YI value.

[0233] (2) Adhesion

[0234] A sheet of 100 mm square and 1 mm thick was prepared from modified polypropylene using a hot press at a set temperature of 200°C, 10 MPa, and 2 minutes. The obtained sheet was then attached to a 100 mm square glass plate and a bonding sample was prepared using a hot press at a set temperature of 200°C, 5 MPa, and 3 minutes.

[0235] The adhesive sample obtained above was cut into 15 mm wide pieces with a cutter, and the test pieces were subjected to a 90° peel test at a speed of 50 mm / min at 23°C to measure the adhesive strength. Evaluation was performed based on the obtained measured values ​​according to the following criteria.

[0236] ○:10N / 15mm or more

[0237] △: 5N / 15mm or more and less than 10N / 15mm

[0238] ×: less than 5N / 15mm

[0239] (3) Heat resistance

[0240] Using a hot press, a sheet of 100 mm square and 1 mm thickness was made from modified polypropylene at a set temperature of 200°C, 10 MPa, and 2 minutes. Samples were cut out of the sheet in a size of 20 mm square and heated in an oven at 200°C for 30 minutes. After heating, the samples were taken out of the oven, and the degree of discoloration of the samples before and after heating was evaluated by visual observation. The case of less discoloration was set as ○, and the case of greater discoloration was set as ×.

[0241]

[0242] <Investigation>

[0243] As shown in Table 1, the reaction rate of maleic anhydride in Examples 1 to 7 using PERBUTYL I (C-1) as a peroxyester (c1) and PERBUTYLD (C-2) as a dialkyl peroxide (c2) as a free radical generator is high, so the result is that the amount of maleic anhydride residue, that is, the content of unsaturated carboxylic acid and / or its derivatives present as monomers (X1-X2) is very low. In addition, the result is that the YI of the modified polypropylene is low and the color tone is excellent. The modified polypropylene manufactured in this way has good adhesion and excellent heat resistance, so the color tone change after the heat resistance test is also small.

[0244] Regarding Comparative Examples 1 to 3 in which only PERBUTYL O as a peroxyester (c1) was used as a free radical generator, the results showed that the amount of maleic anhydride residue, that is, the content (X1-X2) of unsaturated carboxylic acid and / or its derivatives present as a monomer was high, resulting in poor adhesion and a large change in color tone after the heat resistance test.

[0245] Regarding Comparative Example 4 in which 1.4 parts by mass of PERBUTYL I (C-1) and 0.8 parts by mass of PERBUTYLD (C-2) were combined as free radical generators, the results showed that the content (X2) of unsaturated carboxylic acid and / or its derivative graft-polymerized with the modified polypropylene contained in the polymer composition was high, resulting in a large change in color tone after the heat resistance test.

[0246] Regarding Comparative Example 5 in which only PERBUTYLD (C-2) was used as a free radical generator, the results were as follows: the content of unsaturated carboxylic acid and / or its derivatives grafted with the modified polypropylene contained in the polymer composition (X2), and the amount of maleic anhydride residue, i.e., the content of unsaturated carboxylic acid and / or its derivatives existing as monomers (X1-X2) were both high, and the MFR was also a large value, resulting in poor adhesion and a large change in color tone after the heat resistance test.

[0247] Regarding Comparative Example 6 in which 0.4 parts by mass of PERBUTYL I (C-1) and 0.3 parts by mass of PERBUTYLD (C-2) were combined as free radical generators, the results were as follows: the amount of maleic anhydride residue, i.e., the content (X1-X2) of unsaturated carboxylic acid and / or its derivatives present as monomers, was high, resulting in poor adhesion and a large change in color tone after the heat resistance test.

[0248] Although the present invention has been described in detail using specific embodiments, it is apparent to one skilled in the art that various modifications can be made within the scope of achieving the effects of the invention.

[0249] This application is based on Japanese patent application No. 2022-153904 filed on September 27, 2022, the entire contents of which are incorporated by reference.

Claims

1. A polymer composition comprising a modified polypropylene modified with at least one selected from unsaturated carboxylic acids and their derivatives, and The difference (X1-X2) between the mass ratio X1 (mass %) defined below and the mass ratio X2 (mass %) defined below is 0.01 mass % to 0.5 mass %, The following mass ratio X2 (mass %) is 0.7 mass % to 1.8 mass %, The MFR of the polymer composition measured according to JIS K7210 at 180°C, a load of 2.16 kg, and an orifice of 1 mm is 1 g / 10 min to 40 g / 10 min; Mass ratio X1 (mass %): The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes. The obtained disc was used as a measurement sample. The infrared absorption spectrometry was performed according to the wavelength of 1900 to 1600 cm -1 the measured value of the carbonyl characteristic absorption of the polypropylene, the mass ratio (mass %) of the sum of the mass of the unsaturated carboxylic acid and / or its derivative graft-polymerized with the polypropylene in the measurement sample and the mass of the unsaturated carboxylic acid and / or its derivative existing as a monomer in the measurement sample to the measurement sample, calculated using the calibration curve, Mass ratio X2 (mass %): The polymer composition was press-formed into a disc having a thickness of 100 μm and a diameter of 20 mm under the conditions of 200° C., 5 MPa, and 3 minutes. The obtained disc was placed in a Soxhlet extractor and refluxed with acetone at 80° C. for 1 hour. The disc was then dried at 80° C. for 2 hours as a sample for infrared absorption spectrum measurement. The infrared absorption spectrometry was performed based on the wavelengths of 1900 to 1600 cm -1 The mass ratio (mass %) of the unsaturated carboxylic acid and / or its derivative graft-polymerized with the polypropylene in the measurement sample to the measurement sample is calculated using the calibration curve based on the measured value of the carbonyl characteristic absorption.

2. The polymer composition according to claim 1, wherein The MFR measured according to JIS K7210 at 180°C, a load of 2.16 kg, and an orifice of 1 mm is 5 g / 10 minutes to 40 g / 10 minutes. 3 . The polymer composition according to claim 1 , which is a polymer composition for aqueous dispersion.

4. A method for producing a polymer composition according to claim 1, comprising the step of reacting a raw material polypropylene containing a polypropylene (a) having a bending elastic modulus of 100 MPa to 2000 MPa with an unsaturated carboxylic acid and / or a derivative thereof (b) in the presence of a peroxyester (c1) and a dialkyl peroxide (c2).

5. The method for producing a polymer composition according to claim 4, wherein: The peroxyester (c1) is tert-butyl peroxyisopropyl carbonate.

6. The method for producing a polymer composition according to claim 4 or 5, wherein: The dialkyl peroxide (c2) is di-tert-butyl peroxide.

7. The method for producing a polymer composition according to claim 4, wherein: The raw material polypropylene further includes a polypropylene (d) having a bending elastic modulus of less than 100 MPa or a viscosity at 190° C. of 100 cP to 3000 cP.

8. The method for producing a polymer composition according to claim 4, wherein: The content of the polypropylene (a) is 50% by mass to 100% by mass based on 100% by mass of the raw material polypropylene.

9. The method for producing a polymer composition according to claim 7, wherein: The content of the polypropylene (d) is 1% by mass to 50% by mass based on 100% by mass of the raw material polypropylene.

10. An adhesive comprising the polymer composition according to claim 1 or 2.

11. An aqueous dispersion composition comprising the polymer composition according to claim 1 or 2, a surfactant and water.

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