TWI875985B - Adhesive resin composition, adhesive resin molded article, adhesive resin laminate, and housing sealing member - Google Patents

Abstract

The present invention provides an adhesive resin composition having both adhesiveness and gas barrier properties, an adhesive resin molded article, an adhesive resin laminate, and a housing sealing member. More specifically, the present invention is an adhesive resin containing as essential components an acid-modified polyolefin resin （A） and an inorganic filler （B） serving as a gas barrier component. The adhesive resin composition contains the acid-modified polyolefin resin （A） in the range of 50-90 parts by weight and the inorganic filler （B） in the range of 10-30 parts by weight in the total solid content of 100 parts by weight.

Description

Adhesive resin composition, adhesive resin molded body, adhesive resin laminate, and housing sealing material

The present invention relates to an adhesive resin composition, an adhesive resin formed body, an adhesive resin laminate, and a housing sealing material.

Compared to inorganic materials such as metal and glass, organic materials such as resin and rubber have large gaps between polymer molecules and tend to have low gas barrier properties such as oxygen. Therefore, gas barrier properties are imparted by using gas barrier materials. For example, Patent Document 1 describes applying a coating agent in which inorganic filler particles are dispersed in ethylene-vinyl alcohol copolymer (EVOH) to a plastic film. Furthermore, Patent Document 2 describes laminating an inorganic vapor-deposited layer and an inorganic filler-containing layer on a polyethylene naphthalate film in sequence via a transparent primer layer. Prior Art Documents Patent Documents

Patent document 1: Japanese Patent Publication No. 2007-211038 Patent document 2: Japanese Patent Publication No. 5092421

Invent the problem you want to solve

However, Patent Documents 1 and 2 do not disclose any resin film having both adhesiveness and gas barrier properties.

In view of the above situation, the present invention aims to provide an adhesive resin composition, an adhesive resin molded body, an adhesive resin laminate, and a shell sealing material having both adhesiveness and gas barrier properties. Technical method for solving the problem

In order to solve the above problems, the present invention provides an adhesive resin composition, which is characterized in that it contains an acid-modified polyolefin resin (A) as an essential component and an inorganic filler (B) as a gas barrier component, and the acid-modified polyolefin resin (A) and the inorganic filler (B) are contained in an amount within a range of 50 to 90 parts by weight and 10 to 30 parts by weight per 100 parts by weight of the total solid content.

The inorganic filler (B) may be selected from at least one of the group consisting of free titanium oxide, calcium hydroxide, calcium carbonate, barium sulfate, zeolite, aluminum oxide, silicon dioxide, and magnesium silicate. The adhesive resin composition may also contain 1 to 15 parts by weight of the thermoplastic elastomer resin (C) in 100 parts by weight of the total solid content.

Furthermore, the present invention provides an adhesive resin molded body, characterized in that it is composed of an adhesive resin film or an adhesive resin sheet formed by the aforementioned adhesive resin composition. Furthermore, the present invention provides an adhesive resin laminate, characterized in that it is composed of an adhesive resin film or an adhesive resin sheet having an adhesive resin layer composed of the aforementioned adhesive resin composition on at least one side of a base layer.

Furthermore, the present invention provides a shell sealing material, which is characterized in that it is formed by the aforementioned adhesive resin molding. Furthermore, the present invention provides a shell sealing material, which is characterized in that it is formed by the aforementioned adhesive resin laminate. Effect of the invention

According to the present invention, an adhesive resin composition, an adhesive resin molded body, an adhesive resin laminate, and a housing sealing material having both adhesiveness and gas barrier properties can be provided.

The present invention is described below based on a preferred embodiment. The adhesive resin composition according to the embodiment of the present invention contains an acid-modified polyolefin resin (A) as an essential component and an inorganic filler (B) as a gas barrier component.

[Acid-modified polyolefin resin (A)] The acid-modified polyolefin resin (A) is a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, and the polyolefin resin has a carboxyl group or a carboxylic anhydride group. Preferably, the polyolefin resin is modified with an unsaturated carboxylic acid or a derivative thereof. Among the acid-modified polyolefin resins, as the acid-modified method, there can be listed grafting modification such as melt-kneading an acid-functional monomer with a polyolefin resin in the presence of a free radical polymerization initiator such as an organic peroxide or an aliphatic azo compound, copolymerization of an acid-functional monomer with olefins, etc.

As the aforementioned polyolefins, polyethylene, polypropylene, poly-1-butene, polyisobutylene, random copolymers of propylene and ethylene or α-olefins, block copolymers of propylene and ethylene or α-olefins, etc. can be listed. Among them, polypropylene resins such as homopolypropylene (homoPP, propylene homopolymer), propylene-ethylene block copolymers (block PP), and propylene-ethylene random copolymers (random PP) are preferred. Random PP is particularly preferred. As the aforementioned olefins when co-polymerized, olefin monomers such as ethylene, propylene, 1-butene, isobutylene, 1-hexene, and α-olefins can be listed.

As the aforementioned acid-functional monomer, a compound having an ethylenic double bond and a carboxylic acid group or a carboxylic acid anhydride group in the same molecule is composed of various unsaturated monocarboxylic acids, dicarboxylic acids, or anhydrides of dicarboxylic acids. As the acid-functional monomer having a carboxylic acid group (carboxylic acid group-containing monomer), α,β-unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, cisaccharic acid, nadic acid, fumaric acid, itaconic acid, liraconic acid, crotonic acid, isocrotonic acid, tetrahydrophthalic acid, and endo-bicyclo[2.2.1]-5-heptene-2,3-dicarboxylic acid (endic acid) can be listed. Examples of acid-functional monomers having a carboxylic anhydride group (carboxylic anhydride group-containing monomers) include unsaturated dicarboxylic anhydride monomers such as maleic anhydride, nadic anhydride, itaconic anhydride, citric anhydride, and endic anhydride. In the acid-modified polyolefin resin (A), one type of these acid-functional monomers may be used alone, or two or more types may be used in combination.

Among the aforementioned acid-functional monomers, carboxylic anhydride-containing monomers are more preferred, and maleic anhydride is more preferred. When a portion of the acid-functional monomers used for acid modification is unreacted, in order to suppress the adverse effect on adhesion, it is preferred to use the acid-modified polyolefin resin (A) with the unreacted acid-functional monomers removed.

Regarding the propylene component in the acid-modified polyolefin resin (A), it is preferred that the amount of propylene units is more than half from the viewpoint of the heat resistance of the resin. Here, the so-called more than half means that the propylene component is 50% by weight or more of the acid-modified polyolefin resin (A). Therefore, as the acid-modified polyolefin resin (A), an acid-modified polypropylene resin in which the amount of propylene units is more than half is preferred.

[Inorganic filler (B)] Inorganic filler (B) is a gas barrier component that imparts gas barrier properties to the adhesive resin composition. The inorganic filler (B) is not particularly limited as long as it is an inorganic substance, and it is preferably selected appropriately from the perspective of the gas barrier properties of the adhesive resin composition, miscibility with resins such as the acid-modified polyolefin resin (A), and various applicability when used in other products. Suitable metal compounds for the inorganic filler (B) include metal oxides, hydroxides, carbonates, sulfates, silicates, and aluminates. Examples of the metal contained in the inorganic filler (B) include titanium, alkali earth metals (calcium, strontium, barium), alkali metals (sodium, potassium, etc.), aluminum, silicon, magnesium, etc. Specific examples of the inorganic filler (B) include at least one selected from the group consisting of titanium oxide, calcium hydroxide, calcium carbonate, barium sulfate, zeolite, aluminum oxide, silicon dioxide, and magnesium silicate.

Since the inorganic filler (B) functions as a gas barrier component, the following configuration is preferred so that the inorganic filler (B) is well dispersed in the adhesive resin composition, and the inorganic filler (B) particles hinder the movement of gas molecules that want to penetrate the adhesive resin composition. For example, if the dispersion of the inorganic filler (B) is random, there is a risk of local reduction in gas barrier properties at locations where the distribution ratio of the inorganic filler (B) is low. Furthermore, if gaps are generated between the particles of the acid-modified polyolefin resin (A) and the particles of the inorganic filler (B), or between the particles of the inorganic filler (B) due to poor dispersion, there is a risk of reduced gas barrier properties of the adhesive resin composition. When the proportion of the inorganic filler (B) is small, even if the particles of the inorganic filler (B) are well dispersed in the adhesive resin composition, it may be difficult to impart sufficient gas barrier properties.

The adhesive resin composition preferably contains 10 to 30 parts by weight of the inorganic filler (B) based on 100 parts by weight of the total solid content. Furthermore, the adhesive resin composition preferably contains 50 to 90 parts by weight of the acid-modified polyolefin resin (A) based on 100 parts by weight of the total solid content.

In order to disperse the particles of the inorganic filler (B) well and more uniformly in the adhesive resin composition, it is preferred to melt-knead the acid-modified polyolefin resin (A) and the inorganic filler (B). As the melt-kneading device, a single-screw extruder, a multi-screw extruder, a closed-type mixer, a PLASTOMILL mixer, a heating roll kneader, etc. can be used. The heating temperature during melt-kneading is preferably selected from the range of 130 to 300° C. from the point that the acid-modified polyolefin resin (A) is fully melted and does not thermally decompose. When the acid-modified polyolefin resin (A) is a polypropylene-based resin, the kneading temperature is preferably 180 to 300°C, and in order to further improve the dispersibility of the inorganic filler (B), it is preferably 240 to 300°C. The kneading temperature can be measured by a method such as bringing the molten adhesive resin composition into contact with a thermocouple immediately after extrusion from a melt kneading device.

During melt kneading, it is preferred to remove volatile components such as water out of the device in advance. Furthermore, when volatile components are generated during melt kneading, it is desirable to discharge them out of the device at any time by degassing or the like. This can suppress the formation of bubbles when the adhesive resin composition is used to form an adhesive resin molded body or an adhesive resin layer.

[Thermoplastic elastomer resin (C)] The aforementioned adhesive resin composition may contain a thermoplastic elastomer resin (C). Examples of the thermoplastic elastomer resin (C) include styrene elastomers, styrene butadiene copolymers, epoxy-modified styrene butadiene copolymers, olefin elastomers, polyester elastomers, styrene butadiene styrene block copolymers, styrene ethylene propylene styrene block copolymers, styrene isoprene butadiene styrene block copolymers, and styrene isoprene styrene block copolymers. When the adhesive resin composition contains a thermoplastic elastomer resin (C), it is preferred that the thermoplastic elastomer resin (C) is contained in an amount of 1 to 15 parts by weight per 100 parts by weight of the total solid content.

If the thermoplastic elastomer resin (C) does not react with the acid-modified polyolefin resin (A) or the inorganic filler (B) under the conditions of melt-kneading the adhesive resin composition, it can be mixed before melt-kneading. Alternatively, the thermoplastic elastomer resin (C) can be mixed into the adhesive resin composition after the acid-modified polyolefin resin (A) and the inorganic filler (B) are melt-kneaded.

[Adhesive resin composition] According to the embodiment of the present invention, the adhesive resin composition contains an acid-modified polyolefin resin (A) as essential components and an inorganic filler (B) as a gas barrier component. The adhesive resin composition can be melt-kneaded and extruded to produce an adhesive resin layer. The acid functional group of the acid-modified polyolefin resin (A) has excellent adhesion to various substrates such as metals. The adhesive resin composition contains an inorganic filler (B), so that both adhesion and gas barrier properties can be achieved. The adhesive resin composition is a simple composition and can easily produce an adhesive resin layer.

The aforementioned adhesive resin composition may also be appropriately added with fillers, colorants, antioxidants, defoamers, levelers, light absorbers, etc. as other additives. The aforementioned adhesive resin composition may be composed of no resin components or polymer components except the essential components of the acid-modified polyolefin resin (A) and the inorganic filler (B), and the optional component of the thermoplastic elastomer resin (C). The solid content ratio of the other components except the essential components of the acid-modified polyolefin resin (A) and the inorganic filler (B), and the optional component of the thermoplastic elastomer resin (C) may be less than 10 parts by weight, less than 5 parts by weight, 1 part by weight, etc. in 100 parts by weight of the total solid content.

[Substrate] Substrate that can be bonded using the adhesive resin composition according to the embodiment of the present invention can include various substrates such as metal, glass, and plastic. The shape of the substrate is not particularly limited, and can include a film, sheet, plate, flat plate, tray, rod (rod-shaped object), box, shell, etc.

Examples of metals include steel, stainless steel, aluminum, copper, nickel, chromium, and alloys thereof. Furthermore, the invention can also be applied to composite materials having a metal coating on the surface. In this case, the base material of the coating is not particularly limited as long as it can be coated, and can be various materials such as metal, glass, and plastic.

Glass can include alkaline glass, alkali-free glass, quartz glass, etc. Plastics can include polyolefin resins such as polyethylene and polypropylene; polyamide resins such as nylon; aromatic polyester resins such as polyethylene terephthalate (PET); acrylic resins such as polyacrylonitrile (PAN); polyethylene resins such as vinyl acetate (EVA), polyvinyl alcohol (PVA), vinyl alcohol/ethylene copolymer (EVOH), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC); etc.

[Adhesive resin molded body] According to the embodiment of the present invention, the adhesive resin molded body is formed from the aforementioned adhesive resin composition and has a film-like, sheet-like, or other shape, and can be used as an adhesive resin film or adhesive resin sheet. As shown in FIG1 , the adhesive resin molded body 10 can be manufactured by a method of forming an adhesive resin layer 11 in a film-like, sheet-like, or other shape by melt-kneading, extrusion molding, or the like of the aforementioned adhesive resin composition. At least one side of the adhesive resin molded body 10 can be bonded to an adherend 21, 22.

The adhesive resin molded body 10 can be bonded to various adherends by laminating the adhesive resin molded body 10 on one side of the adherend, preferably by heating and pressurizing, by the following methods (1) to (4). (1) A method of bonding the adhesive resin molded body 10 by laminating the adhesive resin molded body 10 on one side of the adherend. (2) A method of bonding the adhesive resin molded body 10 by laminating the adhesive resin molded body on both sides of the adherend. (3) A method of bonding the adhesive resin molded body by laminating the adhesive resin molded body on both sides of the adherend. (4) A method of bonding the adhesive resin molded body 10 by alternately laminating the adhesive resin molded body 10 on the adherend.

[Adhesive resin laminate] The adhesive resin laminate according to the embodiment of the present invention is a laminate having an adhesive resin layer composed of the above-mentioned adhesive resin composition on at least one side of a base layer. As shown in FIG2 , the adhesive resin laminate 10A has an adhesive resin layer 11 on one side or both sides of a base layer 12, and can be bonded to the adherends 21 and 22 using the adhesive resin layer 11. As the base layer 12, the base layer 12 itself does not need to have adhesiveness, and it is preferred that it can be bonded to the adhesive resin layer 11. As in the above examples, various base layers 12 such as metal, glass, and plastic can be used as the adherend. By using a thin base layer 12, the adhesive resin laminate 10A can be used as an adhesive resin film or an adhesive resin sheet.

The adhesive resin laminate can be produced by a method of forming the adhesive resin layer by melt-kneading the adhesive resin composition and extrusion molding. When the base layer is composed of a thermoplastic resin, it can be co-extruded with the adhesive resin composition by extrusion molding. Furthermore, the extrusion molding of the adhesive resin composition can also be performed by extrusion lamination.

When the adhesive resin laminate has the adhesive resin layer only on one side of the substrate layer, the adhesive resin laminate can be bonded to various substrates by heating, preferably by heating and pressurizing, with the substrate volume layer, using the methods listed in (1) or (2) above. Furthermore, when the adhesive resin laminate has the adhesive resin layer on both sides of the substrate layer, the adhesive resin laminate can be bonded to various substrates by heating, preferably by heating and pressurizing, with the substrate volume layer, using the methods listed in (1) to (4) above.

[Shell sealing material] According to the embodiment of the present invention, the shell sealing material can be formed by the aforementioned adhesive resin molded body or the aforementioned adhesive resin laminated body. As shown in FIG. 3 , an adhesive resin molded body 10 is arranged between the adhered bodies 21 and 22 constituting the shell 20, and the adhered bodies 21 and 22 are adhered by using the adhesive resin molded body 10, thereby separating and sealing the internal space 23 of the shell 20 from the outside of the shell 20.

When a pair of adhered bodies 21 and 22 constituting the shell 20 are made of metal, glass, etc., the shell 20 itself has high gas barrier properties, so the adhesive resin molded body 10 that seals the gap between the adhered bodies 21 and 22 is preferably thin. Since the aforementioned adhesive resin composition can be made into a film even with a thickness of 50μm, it is possible to prevent the gas barrier properties in the cross-sectional direction of the shell 20 from being reduced. As a sealing material for the shell 20, an adhesive resin laminate 10A having an adhesive resin layer 11 on both sides of a base layer 12 can be used. The width of the shell sealing material along the cross-sectional direction of the shell 20 is not particularly limited, and can be, for example, about 1 to 5mm.

The above description is based on the preferred embodiment of the present invention, but the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention. Embodiment

The present invention is specifically described below based on embodiments.

(Adhesive resin film) The adhesive resin film of each example and comparative example was prepared using the composition shown in Table 1. The adhesive resin film was prepared by the following method: first, an acid-modified polyolefin resin (A), an inorganic filler (B), and a thermoplastic elastomer resin (C) were melt-kneaded and then formed into a film of a predetermined thickness by extrusion molding. The melt-kneading conditions during extrusion molding were set to 240°C and 2 minutes.

[Table 1]

The meanings of the abbreviations used in Table 1 are as follows. "(A)-1": Maleic acid-modified polypropylene (acid addition 0.1 mass%, melting point 140°C, specific gravity 0.9 g/cm3) "(B)-1": calcium carbonate "(B)-2": zeolite "(B)-3": alumina "(C)-1": propylene-α-olefin copolymer elastomer (softening point 70°C)

(Evaluation method of film forming properties) The appearance of the adhesive resin film obtained by extrusion molding was visually checked. If there was no problem with the appearance, it was evaluated as "○". If there was a defect such as cracking or opening due to unevenness, it was evaluated as "╳".

(Method for measuring bonding strength) As shown in FIG3(a), a sample of an adhesive resin molded body 10 having a length of 20 mm is sandwiched between test adherends 31 and 32 having a length of 50 mm, and heat-pressed as shown in FIG3(b) is performed to produce a test piece 30. The width of the test piece 30 is set to 15 mm. The test piece 30 after heat-pressing is cut in the width direction so that the widths of the adhesive resin molded body 10 and the test adherends 31 and 32 are consistent. As shown in FIG. 3( c ), the ends of the test adherends 31 , 32 not bonded to the adhesive resin molded body 10 are pulled out of the test piece 30 by T-peeling in an approximately 180° direction to measure the bonding strength between the adhesive resin molded body 10 and the test adherends 31 , 32 .

The sample of the adhesive resin molded body 10 is an adhesive resin film with a thickness of 100 μm formed by the adhesive resin composition of the composition shown in Table 1. The test adherends 31 and 32 are aluminum foils with a thickness of 40 μm. The heating and pressing conditions when making the test piece 30 are a temperature of 150°C, a pressure of 0.1 MPa, and a time of 3 seconds. The measurement conditions of the T-peel are a speed of 300 mm/min and a width of 15 mm. When the bonding strength is 5N/15mm or more, it is evaluated as "○", and when it is less than 5N/15mm, it is evaluated as "╳".

(Measurement method of oxygen permeability) The oxygen permeability of the adhesive resin film was measured in accordance with the A method (electrolytic sensing method) of JIS K7126-2 (Plastics - Films and sheets - Gas permeability test methods - Part 2: Isobaric method) at a temperature of 30°C, a humidity of 70% RH, and a measurement area of 50 ^cm2 . The thickness of the adhesive resin film used in the measurement of oxygen permeability was the same as that used in the measurement of adhesive strength, which was set to 100μm.

When the oxygen permeability of the adhesive resin film is less than 1200cc/(m ² ·day·atm), it is evaluated as "○", and when it is 1200cc/(m ^{2 ·} day·atm) or more, it is evaluated as "╳". In addition, due to the limitation of the measuring device, when the measured value is 1800cc/(m ² ·day·atm) or more, the result is expressed as "1800 or more".

[Table 2]

The evaluation results of the adhesive resin films are shown in Table 2. The adhesive resin films of Examples 1 to 5 have good film forming properties and have both sufficient adhesive strength (adhesion) and oxygen permeability (gas barrier properties). Since the adhesive resin film of Comparative Example 1 does not contain the inorganic filler (B), it has higher oxygen permeability and lower gas barrier properties than Examples 1 to 5. Since Comparative Example 2 contains a large amount of inorganic filler (B), on the contrary, the oxygen permeability becomes higher and the gas barrier properties decrease.

10: Adhesive resin molded body 10A: Adhesive resin laminate 11: Adhesive resin layer 12: Base layer 20: Shell 21,22: Adhesive body 23: Inner space of shell 30: Test piece 31,32: Test adhesive body

[Fig. 1] is a cross-sectional view showing an example of the adhesive resin molded body of the present invention. [Fig. 2] is a cross-sectional view showing an example of the adhesive resin laminate of the present invention. [Fig. 3] is a cross-sectional view showing an example of a housing sealed using the housing sealant of the present invention. [Fig. 4] is an explanatory view of a method for measuring bonding strength, showing (a) a method for preparing a test piece, (b) a test piece, and (c) an oblique view of a measuring method.

Claims (6)

An adhesive resin composition, which is an adhesive resin composition containing an acid-modified polyolefin resin (A) as an essential component and an inorganic filler (B) as a gas barrier component, wherein the composition contains 50 to 90 parts by weight of the acid-modified polyolefin resin (A) and 10 to 30 parts by weight of the inorganic filler (B) in 100 parts by weight of the total solid content, wherein the acid-modified polyolefin resin (A) is maleic acid-modified polypropylene, and the inorganic filler (B) is at least one selected from the group consisting of titanium oxide, calcium hydroxide, calcium carbonate, barium sulfate, zeolite, aluminum oxide, silicon dioxide, and magnesium silicate. The adhesive resin composition as described in claim 1, wherein the adhesive resin composition contains 1 to 15 parts by weight of the thermoplastic elastomer resin (C) in 100 parts by weight of the total solid content. A bonding resin formed body, characterized in that it is composed of a bonding resin film or a bonding resin sheet formed by the bonding resin composition as described in claim 1 or 2. An adhesive resin laminate, characterized in that it is composed of an adhesive resin film or an adhesive resin sheet having an adhesive resin layer formed by the adhesive resin composition as described in claim 1 or 2 on at least one side of a base layer. A shell sealing material, characterized in that it is formed by the adhesive resin molding described in claim 3. A shell sealing material characterized by being formed by the adhesive resin laminate described in claim 4.