JP7143106B2 - Adhesive resin composition and composite molded article - Google Patents

Description

The present invention relates to an adhesive resin composition and a molded composite. In particular, it relates to an adhesive resin composition for bonding a polyacetal resin molded article containing a polyacetal resin and a polyethylene resin molded article containing a polyethylene resin.

Polyacetal resins, which are engineering plastics, have excellent mechanical properties, electrical properties, slidability, and chemical resistance, and are therefore widely used, for example, in automobile parts, electric/electronic equipment parts, OA parts, and the like. Among these, applications that take advantage of the excellent chemical resistance of polyacetal resin include flanges, valves, tubes, etc. that are connected to fuel tanks of automobiles, and fuel tank connection parts that come into direct contact with fuel such as gasoline. be done.

On the other hand, in recent years, polyethylene resin has been used as a material for fuel tanks of automobiles for the purpose of reducing the weight of the vehicle body and improving fuel efficiency.

Here, as a method for attaching the fuel tank connection part made of polyacetal resin to a fuel tank using polyethylene resin, for example, a method of welding polyacetal resin and polyethylene resin is known. However, the weldability of the interface between the polyacetal resin and the polyethylene resin is usually low, and there is a problem that the welded portion is easily peeled off by an external force, and the volatile fuel leaks from the interface between the resins. In particular, since fuel has high volatility and can cause air pollution, such fuel leaks are being regulated worldwide. Therefore, there has been a strong demand for the development of a composite molded article in which polyacetal resin and polyethylene resin are integrated.

As an example of such a composite molded body, the following structure is described in Patent Document 1 below.
A thermoplastic resin bonded structure composed of two or more resin components, characterized by having at least one or more structures in which two adjacent components are component (A) and component (B) shown below. A thermoplastic resin joint structure.
(A) component: 5 to 80% by mass of polyacetal resin (hereinafter referred to as component (A-1)) relative to the total mass of component (A), and 20 to 95 masses of the total mass of component (A) % of one or more resin compositions selected from polyolefin resins, olefin elastomers, and hydrogenated butadiene elastomers (hereinafter referred to as component (A-2)).
(B) component; thermoplastic resin

Further, in Patent Document 2 below, a polyacetal resin molded body containing a polyacetal resin (A1), a polyethylene resin molded body containing a polyethylene resin (B3), and a polyacetal resin molded body provided between the polyacetal resin molded body and the polyethylene resin molded body wherein the intermediate layer contains a polyacetal resin (A2) and a polyethylene resin (B2), the intermediate layer only, the polyacetal resin molded body only, the polyacetal resin molded body and only the intermediate layer, only the polyacetal resin molded article and the polyethylene resin molded article, or all of the polyacetal resin molded article, the polyethylene resin molded article and the intermediate layer contain an inorganic filler (C), and the polyacetal Among the resin molded body, the intermediate layer and the polyethylene resin molded body, the content of the inorganic filler (C) in the resin molded body containing the inorganic filler (C) or in the intermediate layer is each greater than 1% by mass. and less than 40 mass %.

JP-A-2002-138185 JP 2017-80939 A

Here, the intermediate layer (adhesive layer) described in Patent Document 2 may contain a stabilizer. Formaldehyde generation can usually be suppressed by incorporating a stabilizer, but it has been found that mold deposits may deteriorate and formaldehyde generation may not be sufficiently suppressed.
An object of the present invention is to solve the above problems, and an adhesive resin composition in which mold deposit is suppressed and formaldehyde generation is suppressed while ensuring a certain adhesiveness, and An object of the present invention is to provide a composite molded article using the adhesive resin composition.

式（１）中、Ｘは、＊１で特定される窒素原子と結合している原子が炭素原子である基であり、Ｙは、＊２で特定される炭素原子と結合している原子が酸素原子または窒素原子である基である。
＜５＞前記無水マレイン酸基でグラフト変性されたポリエチレン樹脂の無水マレイン酸変性率が０．０１質量％以上である、＜１＞～＜４＞のいずれか１つに記載の接着性樹脂組成物。
＜６＞前記ポリアセタール樹脂の１９０℃、２．１６ｋｇ荷重の条件で測定されるメルトフローレイトが６０ｇ／１０分以下である、＜１＞～＜５＞のいずれか１つに記載の接着性樹脂組成物。
＜７＞前記ポリエチレン樹脂の１９０℃、２．１６ｋｇ荷重の条件で測定されるメルトフローレイトが１０ｇ／１０分以下である、＜１＞～＜６＞のいずれか１つに接着性樹脂組成物。
＜８＞前記ポリエチレン樹脂の密度が０．９５４ｇ／ｃｍ^３以下である、＜１＞～＜７＞のいずれか１つに記載の接着性樹脂組成物。
＜９＞ポリアセタール樹脂を含むポリアセタール樹脂成形体と、ポリエチレン樹脂を含むポリエチレン樹脂成形体と、前記ポリアセタール樹脂成形体および前記ポリエチレン樹脂成形体の間に設けられ、前記ポリアセタール樹脂成形体および前記ポリエチレン樹脂成形体と、それぞれ接している中間層とを有し、前記中間層が＜１＞～＜８＞のいずれか１つに記載の接着性樹脂組成物から形成される、複合成形体。 Based on the above-mentioned problems, the present inventors have made intensive studies and found that the above-mentioned problems can be solved by the following means <1>, preferably by <2> to <9>.
<1> At least one selected from the group consisting of a resin component containing a polyacetal resin and a polyethylene resin graft-modified with a maleic anhydride group, and a primary amino group, a secondary amino group, a tertiary amino group and a carbodiimide group The ratio of the compound having the functional group is 0.1% by mass or more of the resin component, and the molar amount of the functional group is 1 when the maleic anhydride group is 1 An adhesive resin composition having a molar ratio [(molar amount of functional group/molar amount of maleic anhydride group)] of 0.15 to 50.
<2> The adhesive resin composition according to <1>, wherein the compound having a functional group is at least one selected from hindered amine compounds, carbodiimide compounds, triazine compounds and urea compounds.
<3> The adhesive resin composition according to <1>, wherein the compound having a functional group is a hindered amine compound.
<4> The adhesive resin composition according to <1>, wherein the compound having a functional group is a hindered amine compound having a structure represented by the following formula (1);
formula (1)

In formula (1), X is a group in which the atom bonded to the nitrogen atom identified by *1 is a carbon atom, and Y is a group in which the atom bonded to the carbon atom identified by *2 is It is a group which is an oxygen atom or a nitrogen atom.
<5> The adhesive resin composition according to any one of <1> to <4>, wherein the polyethylene resin graft-modified with maleic anhydride groups has a maleic anhydride modification rate of 0.01% by mass or more. thing.
<6> The adhesive resin according to any one of <1> to <5>, wherein the polyacetal resin has a melt flow rate of 60 g/10 minutes or less measured under conditions of 190° C. and a load of 2.16 kg. Composition.
<7> The adhesive resin composition according to any one of <1> to <6>, wherein the polyethylene resin has a melt flow rate of 10 g/10 minutes or less measured under conditions of 190°C and a load of 2.16 kg. .
<8> The adhesive resin composition according to any one of <1> to <7>, wherein the polyethylene resin has a density of 0.954 g/cm ³ or less.
<9> Polyacetal resin molded body containing polyacetal resin, polyethylene resin molded body containing polyethylene resin, provided between said polyacetal resin molded body and said polyethylene resin molded body, said polyacetal resin molded body and said polyethylene resin molded body A composite molded article comprising a body and intermediate layers in contact with each other, wherein the intermediate layers are formed from the adhesive resin composition according to any one of <1> to <8>.

INDUSTRIAL APPLICABILITY The present invention provides an adhesive resin composition in which mold deposits are suppressed and formaldehyde generation is suppressed while ensuring a certain degree of adhesiveness, and a composite molded article using the adhesive resin composition. became possible.

1 is a cross-sectional view showing one embodiment of a composite molded article of the present invention; FIG.

The contents of the present invention will be described in detail below. In this specification, the term "~" is used to mean that the numerical values before and after it are included as the lower limit and the upper limit.

The adhesive resin composition of the present invention is a group consisting of a resin component containing a polyacetal resin and a polyethylene resin graft-modified with a maleic anhydride group, and a primary amino group, a secondary amino group, a tertiary amino group and a carbodiimide group. a compound having at least one functional group selected from the above, the ratio of the compound having the functional group is 0.1% by mass or more of the resin component, and the molar amount of the maleic anhydride group is 1 [(molar amount of functional group/molar amount of maleic anhydride group)], which is the molar ratio of the functional groups when With such a configuration, it is possible to provide an adhesive resin composition in which mold deposits are suppressed and formaldehyde generation is suppressed while ensuring a certain level of adhesiveness. Although the reason for this is presumed, when a polyethylene resin graft-modified with a maleic anhydride group is used as the polyethylene resin in an adhesive resin composition containing a polyacetal resin and a polyethylene resin, the maleic anhydride attacks the polyacetal resin. As a result, it was found that mold deposits may occur and the amount of formaldehyde generated may increase. In the present invention, a compound having at least one functional group selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group and a carbodiimide group (hereinafter simply referred to as "compound having a functional group") The above points are effectively suppressed by balancing the amount of maleic anhydride groups modified in the polyethylene resin (hereinafter, sometimes simply referred to as "maleic anhydride modified groups"), and We succeeded in effectively suppressing mold deposits and formaldehyde generation.

<Resin component>
The adhesive resin composition of the present invention contains, as resin components, a polyacetal resin and a polyethylene resin graft-modified with maleic anhydride groups.
The mass ratio of the polyacetal resin and the polyethylene resin is preferably 3-70:97-30, more preferably 10-70:90-30, 20-60:80-40, 25-50. : 75-50, 25-40: 75-60.
The adhesive resin composition of the present invention may contain only one type of polyacetal resin, or may contain two or more types. When two or more kinds are included, the total amount is preferably within the above range. The adhesive resin composition of the present invention may contain only one type of polyethylene resin graft-modified with maleic anhydride groups, or may contain two or more types. When two or more kinds are included, the total amount is preferably within the above range.

In the adhesive resin composition of the present invention, the total of the polyacetal resin and the polyethylene resin preferably accounts for 95% by mass or more, more preferably 97% by mass or more, of the resin components constituting the composition. % by mass or more. 90% by mass or more of the adhesive resin composition of the present invention is preferably a resin component, more preferably 95% by mass or more is a resin component, and 97% by mass or more is a resin component. preferable.

<<Polyacetal Resin>>
The adhesive resin composition of the present invention contains a polyacetal resin. Even if the polyacetal resin contained in the adhesive resin composition is a homopolymer containing only divalent oxymethylene groups as structural units, it contains divalent oxymethylene groups and divalent oxyethylene groups as structural units. Although it may be a copolymer, it is preferably a copolymer containing a divalent oxymethylene group and a divalent oxyethylene group as structural units. When the polyacetal resin is a copolymer containing a divalent oxymethylene group and a divalent oxyethylene group as structural units, the thermal stability is excellent, and the composite molded article is also excellent in thermal stability.

When the polyacetal resin is a copolymer containing a divalent oxymethylene group and a divalent oxyethylene group as structural units, in the polyacetal resin, the ratio of oxyethylene groups to 100 mol of oxymethylene groups (amount of comonomer) is particularly limited. However, it is preferably 1.0 mol or more. In this case, the intermediate layer may have better adhesiveness to the polyethylene resin molding than when the oxyethylene group is contained at a ratio of less than 1.0 mol per 100 mol of the oxymethylene group. As a result, separation between the polyacetal resin molded article and the intermediate layer can be more sufficiently suppressed. The ratio of oxyethylene groups to 100 mol of oxymethylene groups is more preferably 1.2 mol or more, particularly preferably 1.4 mol or more. The ratio of oxyethylene groups to 100 mol of oxymethylene groups is preferably 5.5 mol or less, more preferably 4.0 mol or less, and may be 3.0 mol or less.

Trioxane is usually used as a main raw material for producing the polyacetal resin. In order to introduce an oxyethylene group into the polyacetal resin, for example, 1,3-dioxolane or ethylene oxide may be used as a comonomer.

The melt flow rate (MFR) of the polyacetal resin measured under the conditions of 190° C. and 2.16 kg load is not particularly limited, but is preferably 60 g/10 minutes or less, and 50 g/10 minutes or less. is more preferably 30 g/10 min or less, even more preferably 20 g/10 min or less, even more preferably 10 g/10 min or less, and 5.0 g/10 min or less. It is even more preferable to be 3.0 g/10 minutes or less, and it is particularly preferable to be 3.0 g/10 minutes or less. By setting the melt flow rate to 60 g/10 minutes or less, the intermediate layer has excellent adhesiveness to the polyacetal resin molded article, so that the polyacetal resin molded article 10 and the intermediate layer 20 can be separated sufficiently. can be suppressed. The lower limit of the melt flow rate of the polyacetal resin is not particularly defined, but is preferably greater than 0 g/10 minutes, more preferably 1.0 g/10 minutes or more, and still more preferably 1.5 g/10 minutes or more. is. By setting it as such a range, there exists a tendency for adhesive strength to improve more.
Here, melt flow rate refers to a value measured by a method conforming to ASTM-D1238 standard.

The adhesive resin composition of the present invention preferably contains 3% by mass or more of the polyacetal resin of the composition, more preferably 10% by mass or more, and may contain 20% by mass or more and 25% by mass or more. . Further, the adhesive resin composition of the present invention preferably contains a polyacetal resin in a proportion of 70% by mass or less of the composition, a proportion of 60% by mass or less, a proportion of 50% by mass or less, or a proportion of 40% by mass or less. , 35% by mass or less.

式（２）において、ｍおよびｎは、それぞれ、０を超える数である。本発明では、組成物中無水マレイン酸変性基のモル量と上記官能基を有する化合物に含まれる官能基のモル量が所定の範囲となるように、調整されている限り、ｍとｎの範囲は特に定めるものではない。一例をあげると、ｍは０．０２～５．５であり、ｎは８３０～９７０である。
本発明における無水マレイン酸変性基とは、ポリエチレン樹脂に結合している、無水マレイン酸で変性された基をいう。 <<polyethylene resin>>
The polyethylene resin graft-modified with maleic anhydride groups contained in the adhesive resin composition of the present invention is not limited. Examples of polyethylene resins graft-modified with maleic anhydride groups include high-density polyethylene resins, medium-density polyethylene resins, high-pressure low-density polyethylene resins, linear low-density polyethylene resins, and ultra-low-density polyethylene resins. can.
Examples of polyethylene resins graft-modified with maleic anhydride groups include polyethylene resins containing two types of structural units represented by the following formula (2). The polyethylene resin graft-modified with a maleic anhydride group in the present invention may contain a structural unit other than the two types represented by the following formula (2), but 2 represented by the following formula (2) It is preferable that the total number of structural units of the seed accounts for 90 mol % or more of the total structural units constituting the polyethylene resin graft-modified with maleic anhydride groups.
formula (2)

In formula (2), m and n are numbers greater than 0, respectively. In the present invention, the range of m and n is adjusted so that the molar amount of the maleic anhydride modifying group in the composition and the molar amount of the functional group contained in the compound having the above functional group are adjusted to fall within a predetermined range. is not specified. In one example, m is 0.02-5.5 and n is 830-970.
The maleic anhydride-modified group in the present invention refers to a group modified with maleic anhydride, which is bonded to the polyethylene resin.

The maleic anhydride modification rate in the polyethylene resin graft-modified with maleic anhydride groups is not particularly limited, but the maleic anhydride modification rate is determined based on the total mass of the polyethylene resin graft-modified with maleic anhydride groups. is preferably 0.01% by mass or more. By setting the maleic anhydride modification rate to 0.01% by mass or more, the intermediate layer has excellent adhesiveness to the polyacetal resin molded article, so that the polyacetal resin molded article and the intermediate layer can be separated sufficiently. can be suppressed to The maleic anhydride modification rate of the polyethylene resin graft-modified with maleic anhydride groups is more preferably 0.05% by mass or more, still more preferably 0.10% by mass or more, and still more preferably 0.15% by mass. or more, and more preferably 0.20% by mass or more. In addition, the maleic anhydride modification rate of the polyethylene resin graft-modified with maleic anhydride groups is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and 0.50% by mass. % or less, and even more preferably 0.40 mass % or less.

The polyethylene resin graft-modified with maleic anhydride groups can be produced by uniformly mixing a polyethylene resin, maleic anhydride, and a radical generator, and graft-modifying the polyethylene resin with maleic anhydride. Specific examples of such a production method include a melt-kneading method using an extruder, a Banbury mixer, a kneader, or the like, a solution method of dissolving in an appropriate solvent, a slurry method of suspending in an appropriate solvent, or a so-called gas A phase graft method and the like can be mentioned. The treatment temperature is appropriately selected in consideration of the deterioration of the polyethylene resin, the decomposition of the acid or acid anhydride, the decomposition temperature of the peroxide used, and the like. is usually 190 to 350°C, preferably 200 to 300°C.

In the production of the polyethylene resin graft-modified with maleic anhydride groups, a method of removing unreacted monomers (unsaturated carboxylic acid and its derivatives) and by-product components by heating or washing should be adopted. can be done.

Radical generators used for graft modification include dicumyl peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5 -dimethyl-2,5-di(t-butylperoxy)hexyne-3, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, lauroyl peroxide, t-butyl peroxybenzoate, 1,1,3,3-tetramethylbutyl hydroperoxide, diisopropylbenzene hydroperoxide, t-butylcumyl peroxide, α,α'-bis(t-butylperoxy-m-isopropyl)benzene, di-t -butyl diperoxyisophthalate, n-butyl-4,4-bis(t-butylperoxy)valerate, t-butyl peroxybenzoate, t-butyl peroxyacetate, cyclohexanone peroxide, t-butyl peroxylau and organic peroxides such as acetyl peroxide. Among these, those having a decomposition temperature of 160 to 200° C. for obtaining a half-life of 1 minute are preferred. When the decomposition temperature is 160° C. or higher, it is possible to sufficiently suppress the initiation of the decomposition reaction before the raw material polyethylene resin is sufficiently plasticized in the extruder. °C or less, the reaction is likely to be completed in an extruder or the like.

Examples of polyethylene resins to be modified include high-density polyethylene resins, medium-density polyethylene resins, high-pressure low-density polyethylene resins, linear low-density polyethylene resins, and ultra-low-density polyethylene resins. These may be used singly or in combination of two or more.

The density of the polyethylene resin graft-modified with maleic anhydride groups is preferably 0.970 g/cm ^{3 or less, more preferably 0.954 g/cm 3 or} less. A density of 0.970 g/cm ³ or less enables the intermediate layer to have superior adhesiveness to the polyacetal resin molded article. The density of the polyethylene resin graft-modified with maleic anhydride groups is more preferably 0.940 g/cm ³ or less. The density of the polyethylene resin graft-modified with maleic anhydride groups is preferably 0.912 g/cm ³ or more, more preferably 0.925 g/cm ³ or more. Here, the density of the polyethylene resin graft-modified with maleic anhydride groups is a value measured by a method based on JIS K7112.

The melt flow rate of the polyethylene resin graft-modified with maleic anhydride groups, measured at 190° C. under a load of 2.16 kg, is preferably 10 g/min or less, more preferably 2.5 g/10 min or less. is more preferably 1.5 g/10 minutes or less, even more preferably 1.0 g/10 minutes or less, and even more preferably 0.7 g/10 minutes or less. In particular, when the melt flow rate of the polyethylene resin measured under the conditions of 190° C. and a load of 2.16 kg is 2.5 g/10 minutes or less, compared to the case where the melt flow rate exceeds 2.5 g/10 minutes, It becomes possible for the intermediate layer to have superior adhesiveness to the polyethylene resin molded article, and it is possible to sufficiently suppress separation between the polyacetal resin molded article and the intermediate layer. The lower limit of the flow rate of the polyethylene resin is not particularly defined, but is preferably greater than 0 g/10 minutes, more preferably 0.1 g/10 minutes or more, and still more preferably 0.2 g/10 minutes or more. be.

The adhesive resin composition of the present invention preferably contains 30% by mass or more of the composition, preferably 40% by mass or more, more preferably 50% by mass or more, of the polyethylene resin graft-modified with maleic anhydride groups. is more preferable, more preferably 60% by mass or more, and even more preferably 65% by mass or more. Further, the composition preferably contains a polyethylene resin graft-modified with a maleic anhydride group in a proportion of 97% by mass or less, more preferably 90% by mass or less, and 80% by mass or less. It may be contained in a ratio of mass % or less.
In the adhesive resin composition of the present invention, the number of moles of maleic anhydride modifying groups per 1 g of the composition is preferably 1×10 ⁻⁷ to 4×10 ⁻⁵ , more preferably 5×10 ⁻⁷ to 2×10 −7 . ^-5 is more preferred.
It should be noted that the adhesive resin composition of the present invention does not exclude a mode containing a polyethylene resin other than the polyethylene resin graft-modified with maleic anhydride groups.

<Compound having a functional group>
The adhesive resin composition of the present invention contains a compound having at least one functional group selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group and a carbodiimide group. , a tertiary amino group and a carbodiimide group.
The compound having a functional group is preferably at least one selected from hindered amine compounds, carbodiimide compounds, triazine compounds, hydrazide compounds, semicarbazide compounds, imide compounds and urea compounds. It is more preferably at least one selected, more preferably a hindered amine compound, and even more preferably a hindered amine compound having a structure represented by the following formula (1).
By using at least one selected from hindered amine compounds, carbodiimide compounds and urea compounds, it is possible to further increase the melt flow rate of the resulting adhesive resin composition.

式（１）中、Ｘは、＊１で特定される窒素原子と結合している原子が炭素原子である基であり、Ｙは、＊２で特定される炭素原子と結合している原子が酸素原子または窒素原子である基である。
Ｘはアルキル基であることが好ましく、炭素数１～５のアルキル基であることがより好ましく、炭素数１～３のアルキル基であることがより好ましく、メチル基であることが一層好ましい。Ｙは、酸素原子または炭素原子を含む基である。式（１）で表される化合物を用いることにより、耐熱老化性をより向上させることができる。
上記の中でも、好ましいヒンダードアミン系光安定剤の具体例としては、ビス（１，２，２，６，６－ペンタメチル－４－ピペリジニル）セバケート、１－［２－｛３－（３，５－ジ－ｔ－ブチル－４－ヒドロキシフェニル）プロピオニルオキシ｝エチル］－４－［３－（３，５－ジ－ｔ－ブチル－４－ヒドロキシフェニル）プロピオニルオキシ］－２，２，６，６－テトラメチルピペリジン、１，２，２，６，６－ペンタメチル－４－ピペリジルメタクリレート、テトラキス（１，２，２，６，６－ペンタメチル－４－ピペリジル）－１，２，３，４－ブタンテトラカルボキシレート、１，２，２，６，６－ペンタメチル－４－ピペリジル及びトリデシル－１，２，３，４ブタンテトラカルボキシレート、１，２，３，４－ブタンテトラカルボン酸と１，２，２，６，６－ペンタメチル－４－ピペリジノールとβ，β，β，β－テトラメチル－３，９（２，４，８，１０－テトラオキサスピロ［５，５］ウデンカン）－ジエタノールとの縮合物、Ｎ，Ｎ’ ，Ｎ’ ’，Ｎ’ ’ ’－テトラキス－（４，６－ビス－（ブチル－（Ｎ－メチル－２，２，６，６－テトラメチルピペリジン－４－イル）アミノ）－トリアジン－２－イル）－４，７－ジアザデカン－１，１０－ジアミン、コハク酸ジメチルと４－ヒドロキシ－２，２，６，６－テトラメチル－１－ピペリジンエタノールの縮合物、ビス（１，２，２，６，６－ペンタメチル－４－ピペリジル）［［３，５－ビス（１，１ジメチルエチル）－４－ヒドリキシフェニル］メチル］ブチルマロネート、トリス（１，２，２，６，６－ペンタメチル－４－ピペリジル）－ドデシル－１，２，３，４－ブタンテトラカルボキシレートなどが挙げられる。 formula (1)

In formula (1), X is a group in which the atom bonded to the nitrogen atom identified by *1 is a carbon atom, and Y is a group in which the atom bonded to the carbon atom identified by *2 is It is a group which is an oxygen atom or a nitrogen atom.
X is preferably an alkyl group, more preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group. Y is a group containing an oxygen atom or a carbon atom. Heat aging resistance can be further improved by using the compound represented by formula (1).
Among the above, specific examples of preferred hindered amine light stabilizers include bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, 1-[2-{3-(3,5-di -t-butyl-4-hydroxyphenyl)propionyloxy}ethyl]-4-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]-2,2,6,6-tetra methylpiperidine, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxy 1,2,2,6,6-pentamethyl-4-piperidyl and tridecyl-1,2,3,4 butanetetracarboxylate, 1,2,3,4-butanetetracarboxylic acid and 1,2,2 ,6,6-pentamethyl-4-piperidinol and β,β,β,β-tetramethyl-3,9(2,4,8,10-tetraoxaspiro[5,5]udencan)-diethanol condensate , N,N′ ,N″,N′″-tetrakis-(4,6-bis-(butyl-(N-methyl-2,2,6,6-tetramethylpiperidin-4-yl)amino) -triazin-2-yl)-4,7-diazadecane-1,10-diamine, condensate of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, bis(1 ,2,2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1dimethylethyl)-4-hydroxyphenyl]methyl]butylmalonate, tris(1,2,2, 6,6-pentamethyl-4-piperidyl)-dodecyl-1,2,3,4-butanetetracarboxylate and the like.

The compound having a functional group used in the present invention preferably has a molecular weight of 100-1000.

The compounding amount of the compound having a functional group in the adhesive resin composition of the present invention is 0.1% by mass or more of the resin component. The lower limit of the compounding amount is preferably 0.2% by mass or more, more preferably 0.3% by mass or more. The upper limit of the compounding amount is preferably 1.0% by mass or less, more preferably 0.9% by mass or less, and even more preferably 0.7% by mass or less.
Only one kind of compound having a functional group may be used, or two or more kinds thereof may be used. When two or more are used, the total amount is preferably within the above range.
The adhesive resin composition of the present invention preferably contains 10 ⁻⁶ to 10 ⁻³ functional groups per 1 g of the composition.
Only one type of functional group may be contained in the compound having a functional group, or two or more types may be used. When two or more kinds are used, the total amount is preferably within the above range.

The adhesive resin composition of the present invention has a molar ratio of the functional groups when the molar amount of maleic anhydride groups is 1, [(molar amount of functional groups/molar amount of maleic anhydride groups)]. is 0.15 to 50. The upper limit of the molar ratio is preferably 40 or less, and may be 30 or less, 20 or less, 10 or less, 5.0 or less, or 3.0 or less. Moreover, the lower limit of the above molar ratio may be 0.2 or more and 1.0 or more.

<Other ingredients>
The adhesive resin composition of the present invention may contain components other than the polyacetal resin, the polyethylene resin and the compound having a functional group. Specifically, other components include inorganic fillers, heat stabilizers, antioxidants, weather stabilizers, release agents, lubricants, crystal nucleating agents, antistatic agents, pigments, and the like. These can be used alone or in combination of two or more. Moreover, the adhesive resin composition of the present invention can be configured so as not to substantially contain an inorganic filler. “Substantially free” means that the content of the inorganic filler in the adhesive resin composition of the present invention is less than 1% by mass.
Furthermore, the adhesive resin composition of the present invention includes a dihydrazone compound (in particular, a dihydrazone compound represented by general formula (1) defined in claim 1 of JP-A-2017-025257 (B1) and general formula (2 ) can be substantially free of the dihydrazone compound represented by ). “Substantially free” means that the content of the dihydrazone compound is less than 0.02 parts by mass, preferably 0.01 parts by mass or less, relative to 100 parts by mass of the polyacetal resin.

In the present invention, the difference in melt flow rate between the polyacetal resin contained in the adhesive resin composition and the polyethylene resin graft-modified with maleic anhydride groups measured under conditions of 190° C. and a load of 2.16 kg is 1. It is preferably from 0 to 3.0 g/10 minutes, more preferably from 1.5 to 2.5 g/10 minutes. With such a configuration, the effects of the present invention are exhibited more effectively.
Meltrefflowite (MFR) of the adhesive resin composition of the present invention measured at 190° C. under a load of 2.16 kg is preferably 0.3 g/10 min or more, more preferably 1.0 g/10 min or more. is more preferable, and 2.0 g/10 minutes or more is even more preferable. Although the upper limit of the MVR is not particularly defined, it may be, for example, 5.0 g/10 minutes or less, or 4.0 g/10 minutes or less.

In the present invention, a polyacetal resin molded body containing a polyacetal resin, a polyethylene resin molded body containing a polyethylene resin, and a polyacetal resin molded body provided between the polyacetal resin molded body and the polyethylene resin molded body, the polyacetal resin molded body and the polyethylene resin molded body Disclosed is a composite molded article having a polyethylene resin molded article and an intermediate layer in contact with each other, wherein the intermediate layer is formed from the adhesive resin composition of the present invention.
An embodiment of the composite molded article of the present invention will be described in detail below with reference to FIG. FIG. 1 is a cross-sectional view showing one embodiment of the composite compact of the present invention.

As shown in FIG. 1, a composite molded body 100 is provided between a polyacetal resin molded body 10 containing polyacetal resin, a polyethylene resin molded body 30 containing polyethylene resin, and between the polyacetal resin molded body 10 and the polyethylene resin molded body 30. It has an intermediate layer 20 that is

The intermediate layer 20 is formed from the adhesive resin composition of the present invention.

According to this composite molded body 100, it is possible to sufficiently suppress warping and swelling after contact with the liquid organic compound.
Here, the organic compounds contained in the liquid organic compound include hydrocarbons, alcohols, mixtures thereof, and the like.
Examples of hydrocarbons include aromatic hydrocarbons such as toluene and aliphatic hydrocarbons such as isooctane.
Alcohols include, for example, methanol and ethanol.

<Polyacetal resin molding>
The polyacetal resin contained in the polyacetal resin molded article 10 is not particularly limited as long as it is a polyacetal resin having a divalent oxymethylene group, even if it is a homopolymer containing only a divalent oxymethylene group as a structural unit. , for example, a copolymer containing a divalent oxymethylene group and a divalent oxyethylene group as structural units.

In the above polyacetal resin, the ratio of oxyethylene groups to 100 mol of oxymethylene groups is not particularly limited, and may be, for example, 0 to 5 mol.

Trioxane is usually used as a main raw material for producing the polyacetal resin. In order to introduce an oxyethylene group into the polyacetal resin, for example, 1,3-dioxolane or ethylene oxide may be used as a comonomer.

The melt flow rate of the polyacetal resin measured under the conditions of 190° C. and 2.16 kg load is not particularly limited, and the value of the melt flow rate may be, for example, 0.1 to 200 g/10 minutes.

The polyacetal resin molding 10 should just contain polyacetal resin. Therefore, the polyacetal resin molded body 10 may be composed of only polyacetal resin, or may further contain additives in addition to polyacetal resin. Examples of additives include inorganic fillers, heat stabilizers, antioxidants, weather stabilizers, release agents, lubricants, crystal nucleating agents, antistatic agents, and pigments. These can be used alone or in combination of two or more. Moreover, in the present invention, the polyacetal resin molded article can be configured to substantially contain no inorganic filler. “Substantially free” means that the content of the inorganic filler in the polyacetal resin molded article is less than 1% by mass.
In the present invention, part or all of the polyacetal resin contained in the polyacetal resin molded article and the polyacetal resin contained in the adhesive resin composition may be common or different.

<Polyethylene resin molding> The polyethylene resin contained in the polyethylene resin molding 30 is not particularly limited as long as it is a polyethylene resin. Examples of such polyethylene resin include high-density polyethylene resin, medium-density polyethylene resin, high-pressure low-density polyethylene resin, linear low-density polyethylene resin, and ultra-low-density polyethylene resin. It is preferable that the polyethylene resin contained in the polyethylene resin molding is not acid-modified or has an acid-modified rate of less than 0.01 mass % of the total mass of the polyethylene resin.
The polyethylene resin molding 30 should just contain polyethylene resin. Therefore, the polyethylene resin molded body 30 may be composed only of polyethylene resin, or may further contain additives in addition to polyethylene resin. Examples of additives include inorganic fillers, heat stabilizers, antioxidants, weather stabilizers, release agents, lubricants, crystal nucleating agents, antistatic agents, and pigments. These can be used alone or in combination of two or more.
Moreover, in the present invention, the polyethylene resin molded article can be configured to substantially contain no inorganic filler. “Substantially free” means that the content of the inorganic filler in the polyethylene resin molded article is less than 1% by mass.
In the present invention, part or all of the polyethylene resin contained in the polyethylene resin molding and the polyethylene resin contained in the adhesive resin composition may be common or different.

Regarding the method for producing a composite molded body, the descriptions in paragraphs 0077 to 0090 of JP-A-2017-080939 can be referred to, and the contents thereof are incorporated herein.

The composite molded article of the present invention is applied to, for example, valve devices, recirculation lines, vent lines, flanges for fuel sender modules, and fuel tank connection parts such as swirl tanks that are adhered to the inner wall surface of fuel tanks. It is possible.

EXAMPLES The present invention will be described more specifically with reference to examples below. The materials, usage amounts, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the gist of the present invention. Accordingly, the scope of the present invention is not limited to the specific examples shown below.

<Polyacetal resin (POM)>
POM-1: Oxyethylene groups are contained in a ratio of 1.6 mol per 100 mol of oxymethylene groups, and the melt flow rate (ASTM-D1238 standard: 190°C, 2.16 kg) is 2.5 g/10 minutes. A certain acetal copolymer POM-2: oxyethylene groups are contained in a ratio of 1.6 mol per 100 mol of oxymethylene groups, and the melt flow rate (ASTM-D1238 standard: 190 ° C., 2.16 kg) is 9.0 g / 10 minutes acetal copolymer POM-3: oxyethylene groups are contained in a ratio of 1.6 mol per 100 mol of oxymethylene groups, melt flow rate (ASTM-D1238 standard: 190 ° C., 2.16 kg) is 27 g / 10 minutes acetal copolymer POM-4: oxyethylene groups are contained in a ratio of 1.6 mol per 100 mol of oxymethylene groups, melt flow rate (ASTM-D1238 standard: 190 ° C., 2.16 kg) Acetal copolymer that is 57 g/10 min

<Polyethylene resin (PE)>
PE-1: The density is 0.933 g/cm ³ (JIS K7112 compliant), the melt flow rate (ASTM-D1238 standard: 190° C., 2.16 kg) is 0.5 g/10 min, and the maleic anhydride modification rate is Acid-modified polyethylene resin PE-2, which is 0.21% by mass: density is 0.933 g/cm ³ (JIS K7112 compliant), melt flow rate (ASTM-D1238 standard: 190° C., 2.16 kg) is 0.5 g/cm Acid-modified polyethylene resin PE-3, which is 10 minutes and has a maleic anhydride modification rate of 0.5% by mass: density is 0.933 g/cm ³ (JIS K7112 compliant), melt flow rate (ASTM-D1238 standard: 190 ℃ ^, 2.16 kg) is 0.5 g/10 min, and the maleic anhydride modification rate is 0.01% by mass. , Acid-modified polyethylene resin PE-5 having a melt flow rate (ASTM-D1238 standard: 190 ° C., 2.16 kg) of 1.8 g / 10 minutes and a maleic anhydride modification rate of 0.21% by mass: Density 0.933 g/cm ³ (according to JIS K7112), melt flow rate (ASTM-D1238 standard: 190° C., 2.16 kg) of 9.7 g/10 min, and maleic anhydride modification rate of 0.21% by mass. An acid-modified polyethylene resin PE-6: Density is 0.922 g/cm ³ (JIS K7112 compliant), melt flow rate (ASTM-D1238 standard: 190° C., 2.16 kg) is 0.5 g/10 min, anhydrous Acid-modified polyethylene resin PE-7 having a maleic acid modification rate of 0.21% by mass: density of 0.954 g/cm ³ (JIS K7112 compliant), melt flow rate (ASTM-D1238 standard: 190° C., 2.16 kg) is 0.5 g / 10 minutes, and the maleic anhydride modification rate is 0.21% by mass. Acid-modified polyethylene resin

The maleic anhydride modification rate was measured by hot-pressing maleic anhydride-modified polyethylene at 180° C. to prepare a film of 100 μm and measuring the infrared absorption spectrum. Specifically, the ratio between the absorbance of the peak at 1790 cm ⁻¹ and the absorbance of the peak at 4250 cm ⁻¹ of the infrared absorption spectrum is obtained, and the absorbance ratio value by the prepared infrared spectrum and the value by ¹ H-NMR Obtained from a calibration curve by correlation with maleic anhydride modification rate measurements. The number of maleic anhydride groups in the composition was calculated from the maleic anhydride modification rate.

<Stabilizer>
HALS-1: Tinuvin765, manufactured by BASF, the following compound bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate HALS-2: Tinuvin770, manufactured by BASF, the following compound bis(2,2,6 ,6-tetramethyl-4-piperidinyl) sebacate HALS-3: Tinuvin 622, condensate of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidine ethanol from BASF Triazine: melamine, Chimassorb 944, BASF urea: ethylene urea (2-imidazolidinone), Kanto Kagaku carbodiimide: Carbodilite LA-1, Nisshinbo,
Poly(4,4'-dicyclohexylmethanecarbodiimide)
Nylon 6: UBE Nylon 1013B, manufactured by Ube Industries, Ltd.

<Examples 1 to 25 and Comparative Examples 1 to 3>
Polyacetal resin, polyethylene resin and stabilizer are mixed in a super mixer manufactured by Kawada Seisakusho Co., Ltd. at the blending amounts shown in Tables 1 to 3 to obtain a mixture, and then the mixture is passed through a twin-screw extruder (manufactured by Ikegai Tekko Co., Ltd. "PCM-30", screw diameter 30 mm) and extruded by melt kneading, the strand discharged from the extruder was cooled in a water tank and cut with a pelletizer to obtain pellets of Examples 1 to 25 and Comparative Examples 1 to 3. Got each.

<<Evaluation of Adhesion>>
The adhesive strength was measured according to paragraphs 0110 to 0112 of JP-A-2017-080939. That is, in Example 1 of Japanese Patent Application Laid-Open No. 2017-080939, the pellets obtained above were used as the pellets of the raw material for forming the intermediate layer. A test (adhesion strength to POM) and an adhesion test (adhesion strength to PE) of the intermediate layer to a polyethylene resin molding were measured. Unit is N.

<<Mold Deposit (MD)>>
Using a minimat M8/7A molding machine manufactured by Sumitomo Heavy Industries, Ltd., using a drop-shaped mold as shown in FIG. ,000 shots were continuously molded, and after completion, the state of deposits on the mold was observed with the naked eye and evaluated according to the following four grades of criteria A to D.
A: Almost no mold deposits, very good mold staining resistance B: Some mold deposits, but good mold staining resistance C: Much mold deposits, poor mold staining resistance D : Deposits on the mold spread over the entire surface, and mold contamination is extremely poor.

<<Amount of Formaldehyde Generated>>
The pellets obtained above are dried for 4 hours using a hot air dryer at a temperature of 80 ° C., using an injection molding machine PS-40 manufactured by Nissei Plastic Industry Co., Ltd., at a cylinder temperature of 215 ° C. and a mold temperature of 80 ° C. A flat plate specimen of 100 mm x 40 mm x 2 mm was molded. On the day after the molding, the obtained flat test piece was subjected to formaldehyde generation by the following method in accordance with the method described in German Automobile Manufacturers Association Standard VDA275 (automobile interior parts-quantification of formaldehyde emission amount by revised flask method). The amount (amount of HCHO generated) was measured.
Specifically, 50 mL of distilled water is placed in a polyethylene container, the lid is closed while the test piece is suspended in the air, and the container is sealed and heated at 60°C for 3 hours, then left at room temperature for 60 minutes. The test piece was taken out and the amount of formaldehyde absorbed in the distilled water in the polyethylene container was measured by the acetylacetone colorimetric method using an ultraviolet (UV) spectrometer.
The amount of formaldehyde generated was shown as a ratio (mass ratio) of the amount of formaldehyde generated in each example and comparative example when the amount of formaldehyde generated in Comparative Example 1 was taken as 100.

<<Melt Flow Rate (MFR)>>
The MFR was measured under conditions of 190° C. and a load of 2.16 kg in accordance with ISO1133.

<<Heat aging resistance>>
The pellets obtained above were molded into ISO3167-1A type test pieces at a cylinder temperature of 195°C and a mold temperature of 90°C. After leaving the molded piece in an environment of 23° C. and 50% RH (relative humidity) for 24 hours, the color was measured using a spectral color difference meter SE6000 manufactured by Nippon Denshoku Industries Co., Ltd. under the conditions of a C light source viewing angle of 2°, and then 120° C. and aged in a hot air circulation oven for 500 hours. The color of the treated test piece was similarly measured to determine the color difference (ΔE) before and after the treatment.

The number of maleic anhydride groups in Tables 1 to 3 means the number of maleic anhydride groups graft-modified on the polyethylene resin. As is clear from the above results, the adhesive resin composition of the present invention suppresses mold deposit while ensuring a certain degree of adhesion to polyacetal resin molded articles and polyethylene resin molded articles, and does not generate formaldehyde. It was found to be suppressed (Examples 1-25).
On the other hand, when the stabilizer was not blended (Comparative Example 1) and when the amount of the stabilizer blended was small (Comparative Example 2), the mold deposit deteriorated. In addition, a large amount of formaldehyde was generated.
Further, among the stabilizers, by using any one of the hindered amine compound, the carbodiimide compound and the urea compound, an adhesive resin composition with a higher MFR was obtained (Examples 1 to 6).
Furthermore, among hindered phenol compounds, it was found that by using those having a specific structure, an adhesive resin composition having excellent heat aging resistance can be obtained (Examples 1 and 3 and Example 2 comparison).

Manufacture of Composite Molded Body A composite molded body was formed by two-color insert molding using the pellets obtained in Example 1, the pellets of the raw material for forming the polyacetal resin molded body, and the pellets of the raw material for forming the polyethylene resin molded body.
Iupital F20-01 manufactured by Mitsubishi Engineering-Plastics Co., Ltd. was used as the raw material pellet for forming the polyacetal resin molded body. Novatec HJ221 manufactured by Nippon Polyethylene Co., Ltd. was used as raw material pellets for the polyethylene resin molding. The polyethylene resin used for the raw material pellets for the polyethylene resin molding is not acid-modified.

10 polyacetal resin molding 20 intermediate layer 30 polyethylene resin molding 100 composite molding

Claims (9)

a resin component comprising a polyacetal resin and a polyethylene resin graft-modified with maleic anhydride groups;
A compound having at least one functional group selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group and a carbodiimide group,
The ratio of the compound having the functional group is 0.1% by mass or more of the resin component,
[(molar amount of functional group/molar amount of maleic anhydride group)], which is the molar ratio of the functional group when the molar amount of the maleic anhydride group is 1, is 0.15 to 50;
When the mass ratio of the polyacetal resin and the polyethylene resin graft-modified with the maleic anhydride group is 100 parts by mass in total, the polyethylene resin graft-modified with the maleic anhydride group is more than 50 parts by mass and 75 parts by mass. and
The adhesive resin composition, wherein the compound having a functional group is at least one selected from hindered amine compounds, carbodiimide compounds, triazine compounds, hydrazide compounds, semicarbazide compounds, imide compounds and urea compounds . 2. The adhesive resin composition according to claim 1, wherein said compound having a functional group is at least one selected from hindered amine compounds, carbodiimide compounds, triazine compounds and urea compounds. The adhesive resin composition according to claim 1, wherein the compound having a functional group is a hindered amine compound. The adhesive resin composition according to claim 1, wherein the compound having a functional group is a hindered amine compound having a structure represented by the following formula (1);
formula (1)

In formula (1), X is a group in which the atom bonded to the nitrogen atom identified by *1 is a carbon atom, and Y is a group in which the atom bonded to the carbon atom identified by *2 is It is a group which is an oxygen atom or a carbon atom. The adhesive resin composition according to any one of claims 1 to 4, wherein the polyethylene resin graft-modified with maleic anhydride groups has a maleic anhydride modification rate of 0.01% by mass or more. The adhesive resin composition according to any one of claims 1 to 5, wherein the polyacetal resin has a melt flow rate of 60 g/10 minutes or less measured under conditions of 190°C and a load of 2.16 kg. Adhering to any one of claims 1 to 6, wherein the polyethylene resin graft-modified with maleic anhydride groups has a melt flow rate of 10 g/10 minutes or less measured under conditions of 190 ° C. and a load of 2.16 kg. elastic resin composition. The adhesive resin composition according to any one of claims 1 to 7, wherein the polyethylene resin graft-modified with maleic anhydride groups has a density of 0.954 g/cm ³ or less. A polyacetal resin molded body containing a polyacetal resin, a polyethylene resin molded body containing a polyethylene resin, and provided between the polyacetal resin molded body and the polyethylene resin molded body, the polyacetal resin molded body and the polyethylene resin molded body, 9. A composite molded article having intermediate layers in contact with each other, wherein the intermediate layers are formed from the adhesive resin composition according to any one of claims 1 to 8.

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