JP5372437B2 - Polyolefin adhesive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive composition suitably usable for adhesion of a polyolefin molded article as a structural member of an automobile interior material and a fabric with polyurethane foam or the like. <P>SOLUTION: The adhesive composition comprises (A) a modified polyolefin resin modified with an unsaturated carboxylic acid and/or its derivative, (B) a compound having a functional group reactive with the modified polyolefin resin (A) and a reactive silyl group, and/or a reaction product of the modified polyolefin resin (A) and the compound (B). <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a polyolefin-based adhesive composition, and more particularly, a polyolefin-based adhesive particularly useful for bonding a polyolefin molded article, which is a component of an automobile interior material, to a polyurethane foam, a fabric with a polyurethane foam, or the like. Relates to the composition.

  In general, automobile interior materials (for example, ceilings, door trims, instrument panels, dashboard silencers, center consoles, pillars, ornaments, rear parcels, seats, etc.) are molded products of polyolefins such as polypropylene and polyethylene, and polyolefin skins and polyurethane foams. It is manufactured by adhering a decorative material such as a fabric with polyurethane foam with an adhesive using a vacuum forming method, a press-bonding method, or the like. Conventionally, a polychloroprene adhesive has been used for such adhesion (see, for example, Patent Document 1). However, from the viewpoint of environmental safety, an alternative from a polychloroprene adhesive to a halogen-free adhesive is desired.

  As an alternative to polychloroprene adhesives, styrene resin adhesives based on silane-modified styrene copolymers have been developed (see, for example, Patent Document 2). Such a styrene resin-based adhesive does not contain halogen, but its heat-resistant adhesiveness to polyolefin is not sufficient, and when an olefin-based adhesive is added to improve the heat-resistant adhesive, problems such as phase separation occur. there were. Furthermore, such an adhesive has a problem that it has poor adhesion to polyurethane foam, fabric with polyurethane foam, and the like.

On the other hand, as a polyolefin-based adhesive composition, an adhesive composition based on a polyolefin resin modified with an unsaturated carboxylic acid and / or a derivative thereof has been developed (see, for example, Patent Documents 3 and 4). However, these polyolefin-based adhesive compositions are hot-melt adhesive compositions, and when used as the base polymer of the adhesive, when the adhesive is applied to an adherend with a spray and a brush, and the adhesive Since the adherend needs to be heated when the adherend to which the coating is applied is bonded, the material of the adherend is limited or even in the case of an adhesive composition using a solvent as a solvent. There was a problem that it was necessary to do dangerous work.
Japanese Patent Laid-Open No. 5-140522 JP 2000-303047 A JP 2001-131250 A JP 2004-292716 A

  An object of the present invention is to provide a polyolefin molded article as a component of an automotive interior material, which exhibits excellent adhesion to not only polyolefin materials but also polyurethane materials, and also exhibits excellent heat resistance, polyurethane foam, It is to provide an adhesive composition that can be suitably used for adhesion to a polyurethane foamed fabric or the like.

  The inventors of the present invention have made extensive studies to achieve the above-mentioned problems. As a result, (A) a modified polyolefin resin modified with an unsaturated carboxylic acid and / or a derivative thereof, and (B) the modified polyolefin resin (A ) And / or a compound having a reactive silyl group and / or a reaction product of the modified polyolefin resin (A) and the compound (B). The present inventors have found that the above problems can be solved by the adhesive composition, and have completed the present invention.

That is, the following embodiments are included in the present invention.
[1] (A) a modified polyolefin resin modified with an unsaturated carboxylic acid and / or a derivative thereof;
(B) a compound having a functional group reactive with the modified polyolefin resin (A) and a compound having a reactive silyl group, and / or the modified polyolefin resin (A) and the compound (B) An adhesive composition comprising a reaction product of
[2] The adhesive composition according to [1] above, wherein the modified polyolefin resin (A) has a glass transition temperature of −50 to 80 ° C.
[3] The adhesive composition according to [1] or [2] above, wherein the compound (B) is a radically polymerizable compound having a reactive silyl group.
[4] The adhesive composition according to any one of [1] to [3], wherein the unsaturated carboxylic acid and / or derivative thereof is (meth) acrylic acid and / or a (meth) acrylic acid derivative.

  The adhesive composition of the present invention exhibits excellent adhesion to not only polyolefin materials but also polyurethane materials, and also exhibits excellent heat resistance. It can be suitably used for adhesion to polyurethane foam, polyurethane foam fabric and the like.

  The modified polyolefin resin (A) modified with the unsaturated carboxylic acid and its derivative used in the present invention is obtained, for example, by graft-modifying a polyolefin resin with a radical polymerizable unsaturated carboxylic acid and / or its derivative. Can be mentioned.

Examples of the polyolefin resin in the modified polyolefin resin (A) include polypropylene, polyethylene, polybutene, propylene-ethylene copolymer, propylene-butene copolymer, styrene-butadiene-styrene block copolymer, styrene-hexadiene-styrene. Copolymer, styrene-pentadiene-styrene copolymer, ethylene-propylene-diene copolymer (RPDM) and the like, preferably ethylene-butene copolymer, propylene-butene copolymer, propylene-ethylene- Examples include butene copolymers. These may be used alone or in combination of two or more.
Of these, a propylene-butene copolymer, a propylene-ethylene-butene copolymer, and the like are particularly preferable from the viewpoint of adhesion to an olefin resin.
The weight average molecular weight of the polyolefin resin is not particularly limited, but the weight average molecular weight after being modified with an unsaturated carboxylic acid and / or a derivative thereof (modified polyolefin resin (A)) is in the range described below. It is preferable.
In addition, the weight average molecular weight in this invention means the value determined by the weight average molecular weight measuring method by a liquid chromatography.

  Examples of the unsaturated carboxylic acid and derivatives thereof in the modified polyolefin resin (A) include radically polymerizable unsaturated compounds having one or more carboxylic acid groups in the molecule and derivatives thereof. Examples thereof include radically polymerizable groups such as vinyl group, vinylene group and unsaturated cyclic hydrocarbon group. Examples of the unsaturated compound include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid and the like. Examples of the derivative of the unsaturated compound include acid anhydrides, ester compounds, amide compounds, imide compounds, metal salts and the like. Specifically, maleic anhydride, methyl (meth) acrylate, butyl ( (Meth) acrylylate, 2-ethylhexyl acrylate, glycidyl (meth) acrylate, maleic acid monoethyl ester, maleic acid diethyl ester, fumaric acid monomethyl ester, fumaric acid dimethyl ester, maleic acid diamide, fumaric acid monoamide, maleimide, N-butyl maleimide , Sodium methacrylate, vinyl acetate and the like. These may be used alone or in combination of two or more. Of these, (meth) acrylic acid and derivatives thereof are preferable from the viewpoint of adhesion to adherends other than olefins, such as polyurethane, and 2-ethylhexyl acrylate and methyl (meth) acrylate are particularly preferable.

The modified amount (content) of the unsaturated carboxylic acid and / or derivative thereof in the modified polyolefin resin (A) is preferably 1 to 95% by weight, particularly preferably 10 to 90% by weight, based on the whole resin. It is. If the amount of modification is less than 1% by weight, the sprayability when applied by spraying may be reduced due to the decrease in solubility in the solvent, and the adhesive may be separated. There is a risk of lowering the adhesiveness and wettability of the adherend. On the other hand, when it exceeds 95 weight%, there exists a possibility of causing the remarkable fall of the adhesiveness to polyolefin resin as a to-be-adhered body.
The content (modified amount) of the unsaturated carboxylic acid and / or derivative thereof means a value that can be determined by the blending ratio during polymerization.

The modified polyolefin resin (A) can be produced by, for example, a known method used for graft modification of a polyolefin resin, such as a melting method or a solution method.
In the melting method, a polyolefin and an unsaturated carboxylic acid are kneaded with an organic peroxide, melted, mixed, and reacted. This can be performed using, for example, an extruder, a brabender, a kneader, an intensive mixer, a blast mill, or the like. The kneading temperature is preferably in the temperature range from the melting point to 300 ° C. of the polyolefin used.
The solution method can be obtained by dissolving polyolefin and unsaturated carboxylic acid in an organic solvent, adding an organic peroxide and heating. As the organic solvent to be used, a hydrocarbon having 6 to 12 carbon atoms or a halogenated hydrocarbon having 6 to 12 carbon atoms can be used. The reaction temperature is preferably a temperature at which the polyolefin to be used is dissolved.

The modified polyolefin resin (A) preferably has a glass transition temperature (Tg) of −50 to 80 ° C., particularly preferably −30 to 70 ° C. When Tg is less than −50 ° C., there is a risk of causing a decrease in adhesion due to cohesive failure when used as an adhesive. On the other hand, when Tg exceeds 80 ° C., the adherend is used when used as an adhesive. The adhesive strength is reduced due to the decrease in wettability of the resin. In particular, if the open time until bonding is increased, the adhesive strength may be significantly reduced.
In addition, the glass transition temperature (Tg) in this invention means the value which can be determined by the measurement by dynamic viscoelasticity.

  The modified polyolefin resin (A) preferably has a weight average molecular weight of 5000 or more, particularly preferably 10,000 or more. When the weight average molecular weight is less than 5,000, the heat resistance may be significantly reduced. On the other hand, the upper limit of the weight average molecular weight is not particularly limited, but when it exceeds 100,000, there is a risk of lowering the solubility in a solvent and the wettability of the adhesive of the present invention to the adherend, preferably 70,000 or less.

The compound (B) having a functional group reactive to the modified polyolefin resin (A) used in the present invention and a reactive silyl group reacts with the modified polyolefin resin (A) to thereby modify the modified polyolefin resin. Used to impart a moisture crosslinking group to (A).
The compound (B) is not particularly limited as long as it is a compound having a functional group reactive to the modified polyolefin resin (A) and a reactive silyl group. For example, radical polymerization having a reactive silyl group Specific compounds such as vinyl silane (for example, vinyltrimethoxysilane, vinyltriethoxysilane), styrylsilane (for example, p-styryltrimethoxysilane), methacryloxysilane (for example, 3- Methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, etc., acryloxysilane (for example, 3-acryloxypropyltrimethoxy) Silane etc.) It is below. These may be used alone or in combination of two or more.
Of these, methacryloxysilane is preferred from the viewpoint of reactivity with the modified polyolefin resin (A).

  The content of the compound (B) in the adhesive composition of the present invention is preferably 5 parts by weight or more, particularly preferably 20 parts by weight with respect to 100 parts by weight (solid content) of the modified polyolefin resin (A). That's it. When the compound (B) is less than 5 parts by weight with respect to 100 parts by weight of the modified polyolefin resin (A), there is a possibility that the heat resistance performance of the adhesive is lowered. Although there is no upper limit in particular in content of (B), when it exceeds 100 weight part, there exists a possibility that a sediment may generate | occur | produce.

In the adhesive composition of the present invention, part or all of the modified polyolefin resin (A) and the compound (B) may be contained as a reaction product thereof.
In the adhesive composition of the present invention, preferably, at least a part of the compound (B), for example, 5 to 100% by weight, preferably 20 to 100% by weight of the whole compound (B) is the modified polyolefin resin ( It is preferably contained as a reaction product with A). In this case, moisture curability is possible and heat resistance can be imparted. In this case, it is advantageous in terms of the cost of the adhesive composition.

The reaction product is obtained, for example, by reacting the modified polyolefin resin (A) and the compound (B) for 60 to 360 minutes under a heating (for example, 60 to 90 ° C.) stirring condition using a polymerization initiator. be able to.
The polymerization initiator may be, for example, a compound that generates a radical by heating. Specifically, a peroxide such as benzoyl peroxide, hydroperoxide, dialkyl peroxide, peroxyketal, peroxyketal, Examples thereof include azo initiators such as 2,2-azobisisobutyronitrile. These may be used alone or in combination of two or more.
Especially, the polymerization initiator which has a half life at 60-100 degreeC, for example, a benzoyl peroxide, a hydroperoxide etc. is preferable from the point of polymerizability and the safety | security at the time of handling.
The amount of the polymerization initiator used in the reaction is preferably 0.05 to 10 parts by weight, particularly preferably 0. 0 parts by weight with respect to 100 parts by weight (solid content) of the modified polyolefin resin (A) from the viewpoint of reaction rate. 1 to 5 parts by weight.

  The adhesive composition of the present invention may further contain a polymerization initiator as described above, particularly when it contains unreacted modified polyolefin resin (A) and compound (B). In this case, the content of the polymerization initiator in the adhesive composition is the same as the amount used in the above reaction.

The adhesive composition of the present invention may be prepared by adding various additives known in the art such as a reaction terminator, a dehydrating agent, an anti-aging agent, a solvent, a tackifier resin, and a colorant, as necessary. You may contain in the quantity within the range which can achieve the objective of a composition.
Examples of the reaction terminator include hydroquinone, 4-methoxyphenol, phenothiazine, bis-α-methylbenzylphenothiazine, 4,4′-butylidene-bis (3-methyl-6-t-butylphenol), t-butylcatechol. Etc.
Examples of the dehydrating agent include alkoxysilane compounds such as methyltrimethoxylane, methyltriethoxysilane, and dimethyldiethoxysilane.
Examples of the anti-aging agent include amine-based anti-aging agents, phenol-based anti-aging agents, thiocarbonyl-based anti-aging agents, dianneal-P-phenylenediamine-based anti-aging agents, and phenylisopropyl-P-phenylenediamine-based anti-aging agents. And amine-ketone aging inhibitors.
Examples of the solvent include ethyl acetate, butyl acetate, propyl acetate, methyl ethyl ketone, methyl isobutyl ketone, hexane, heptane, cyclohexane, methylcyclohexane, and ethylcyclohexane.
Examples of the tackifying resin include petroleum resins, rosin resins, terpene resins, coumarone-indene resins, xylene resins, phenol resins, and modified products of these resins.
Examples of the colorant include azo dyes, anthraquinone dyes, phthalocyanine dye pigments, diphenylmethane dyes, triphenylmethane dyes, acid dyes, and basic dyes.

  The adhesive composition of the present invention can be produced by sequentially adding and mixing the above components (A) and (B) and other components (polymerization initiator, additive, etc.) according to a conventional method. Here, the components (A) and (B) may be reacted in advance before mixing other components, if necessary, and reacted after mixing other components (especially polymerization initiator). May be.

  The adhesive composition of the present invention is usually applied on an adherend according to a conventional method (for example, spray method), dried (usually from room temperature to 120 ° C. for several seconds to 10 minutes), and air. It can be cured (usually 5 to 100% RH (relative humidity) at −10 to 100 ° C. for 2 to 48 hours) by moisture inside.

  The adhesive composition of the present invention has excellent adhesion to not only polyolefin materials such as polypropylene and polyethylene but also polyurethane materials such as polyurethane foam, and is excellent in heat resistance. Vacuum molding of interior molding materials such as ceilings, door trims, instrument panels, dash silencers, center consoles, pillars, ornaments, rear parcels, seats, etc., polyolefin moldings, polyurethane foam, fabrics with polyurethane foam, etc. It is particularly suitable for bonding using a method, a crimping method or the like.

Next, the present invention will be described more specifically with reference to examples and comparative examples. In addition, the evaluation item and evaluation method of the adhesive composition of an Example and a comparative example are shown below.
[Evaluation items and methods]
(1) Initial creep The adhesive composition was applied and dried under the following conditions, and the base material and the skin material were bonded together, and the peel length (mm) after 5 minutes (load: 200 g) at 60 ° C. It was measured.
(2) Normal peeling Peel strength after applying and drying the adhesive composition under the following conditions, bonding the base material and the skin material, and curing for 24 hours at 20 ° C. and 65% RH (relative humidity) (N / 25 mm) was measured and evaluated as follows.
CF: cohesive failure of adhesive FAF: interface failure from the skin side FMB: material failure of the skin material BAF: interface failure from the substrate side (3) heat-resistant creep The adhesive composition was applied and dried under the following conditions The base material and the skin material are bonded together, cured at 20 ° C. and 65% RH (relative humidity) for 24 hours, and the peel length (mm) after 24 hours (load: 50 g, 100 g, 150 g) at 80 ° C. ) Was measured.
(Bonding conditions)
Substrate: Base PP (polypropylene) x skin adhesive material with a polyurethane foam coating amount: 150 g / m ²
Drying: 80 ° C. × 2 minutes Open time: Room temperature × 1 minute Clamping: 0.2 MPa × 10 seconds

[Examples 1-3 and Comparative Examples 1 and 2]
Each component (parts by weight) shown in Table 1 below was blended to produce each adhesive composition. Each obtained adhesive composition was evaluated as described above. The results are shown in Table 1.

In the table,
(A1) Acrylic-modified olefin resin: “NP-1000” manufactured by Toyo Kasei Kogyo Co., Ltd. (propylene modified with methyl methacrylate (MMA) (75 wt%) / 2-ethylhexyl acrylate (EHA) (25 wt%)) (Butene copolymer: 85% by weight of acrylic modification, Tg: 40 to 50 ° C., weight average molecular weight 60000, resin solid content 30% by weight)
(A2) Acrylic modified olefin resin: "NP-1001" (MMA (50 wt%) / EHA (50 wt%) modified by Toyo Kasei Kogyo Co., Ltd.); acrylic modified amount 85 wt% %, Tg: 20 to 30 ° C., weight average molecular weight 60000, resin solid content 30% by weight)
(A3) Acrylic modified olefin resin: "NP-3001" (MMA (75 wt%) / EHA (25 wt%) modified by Toyo Kasei Kogyo Co., Ltd.); acrylic modified amount 70 wt %, Tg: 0 to 10 ° C., weight average molecular weight 60000, resin solid content 30% by weight)
(A4) Chlorine-modified olefin resin: “892LS” manufactured by Nippon Paper Chemical Co., Ltd. (polypropylene modified with chlorine; chlorine-modified amount 22 wt%, Tg: 15 to 25 ° C.)
(B) Silane coupling agent: 3-methacryloxypropyltrimethoxysilane, “KBM-503” manufactured by Shin-Etsu Chemical Co., Ltd.
(C) Peroxide: benzoyl peroxide, “Nyper FF” manufactured by NOF Corporation
(D) Reaction terminator: Hydroquinone (E) Stabilizer: Methyltrimethoxysilane, “KBM-13” manufactured by Shin-Etsu Chemical Co., Ltd.
(F) Solvent: Ethyl acetate (G) Tackifying resin: Polymerized rosin ester, “Pencel D-160” manufactured by Arakawa Chemical Industries, Ltd.
(H) Colorant: “Oil Blue 2N” manufactured by Orient Chemical Industry Co., Ltd.

  As shown in Table 1 above, in the adhesive compositions of the examples, it was recognized that excellent adhesiveness was exhibited not only for polyolefin materials but also for polyurethane materials, and also exhibited excellent heat resistance. It was.

Claims (2)

(A) a modified polyolefin resin modified with (meth) acrylic acid and / or a (meth) acrylic acid derivative ;
(B) 5 to 100 parts by weight (excluding 5 parts by weight) of the modified polyolefin resin (A) as a reference and functional groups and reactivity having reactivity with the modified polyolefin resin (A) An adhesive composition comprising a compound having a silyl group and / or a reaction product of the modified polyolefin resin (A) and the compound (B), the compound (B) Is a radically polymerizable compound having a reactive silyl group.   The adhesive composition of Claim 1 whose glass transition temperature of modified polyolefin resin (A) is -50-80 degreeC.