JP2012020418A - Molded body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate which includes a resin layer exerting high adhesiveness with respect to various types of base materials by heating at low temperature and having low tackiness by finger touching and is useful as a hole plug structure to close an opening formed on a plate-shaped member such as an automobile chassis.SOLUTION: A molded body includes: a resin member (I) containing modified ethylene-based copolymer (a) formed by grafting at least one monomer (graft monomer) of unsaturated carboxylic acid and/or derivatives thereof into ethylene-based copolymer which is copolymer of ethylene with 3-8C α-olefin and has ≤4.0 of Mw/Mn; and a metallic member and/or a resin member (II) other than the resin member (I). The resin member (I) has 50-110°C of a melting point and includes 0.03-2 wt.% of a component derived from the graft monomer. The resin member (I) serves as a seal ring for a hole plug, and the metallic member and/or the resin member (II) serves as the plate-shaped member for closing the opening by the hole plug.

Description

The present invention relates to a molded body having a resin member with low finger touch adhesion while exhibiting high adhesion to various base materials by low-temperature heating, and in particular, formed on a plate-like member such as an automobile chassis. The present invention relates to a molded body useful for a hole plug structure for closing a formed opening.
The present invention also relates to a seal plug for a hole plug that exhibits high adhesion to various base materials when heated at a low temperature and has low finger-tackiness.

A plate-like member such as a chassis of an automobile is formed with a plurality of openings for use in securing a liquid breakage in an application process such as electrodeposition coating or in an assembly process.
These openings become unnecessary after the above purpose of use has been achieved, but if this opening remains in the product as it is, it will cause corrosion of the member due to rain water and muddy water at the time of traveling, or ingress of dust and dirt at rest, It may cause a failure or a shortened service life.

For this reason, hole plugs are used to close these openings.
The structure of the plate member and the hole plug will be described with reference to FIG. FIG. 1 is a cross-sectional view showing an example of the structure and usage of a hole plug. A hole plug 10 (FIG. 1B) is for closing an opening 2 of a plate-like member 1 such as a chassis (FIG. 1). (D)). The hole plug 10 includes a hole plug main body 3 and a seal ring 4 that engages with the main body 3 (FIG. 1B). The main body 3 is generally made of engineering plastic such as 6-nylon or polyphenylene ether, and has a base portion 5 having a larger diameter than the opening 2 and a protruding portion 6 projecting from the base portion 5 and having a smaller diameter than the opening 2. (FIG. 1A). The seal ring 4 is for fusing the main body 3 and the plate-like member 1 together. (In the present invention, “fusion” includes the concept of “adhesion” using a solvent.) That is, the hole plug body 3 mainly composed of engineering plastic is a plate such as a chassis. The seal ring 4 made of a thermoplastic resin for fusing both of the main body 3 and the plate-like member because the fusing property between the metal member 1 and the electrodeposited surface coated on the metal surface is poor. 1 is inserted.

  In order to close the opening 2 of the plate member 1 using such a hole plug 10, the protrusion 6 is opened while the seal ring 4 is sandwiched between the protrusion 6 side of the base 5 and the plate member 1. After inserting into 2 and making it the state of FIG.1 (c), the seal ring 4 is fuse | melted by heating the vicinity of the opening 2. FIG. When the seal ring 4 is melted, the gap between the opening 2 and the protruding portion 6 of the main body 3 and the gap between the base portion 5 of the main body 3 and the plate surface of the plate-like member 1 are filled with molten resin. By solidifying, as shown in FIG. 1 (d), the plate-like member 1 and the hole plug body 3 are fixed and the space between them is sealed. In FIG.1 (d), 4A shows the solidified sealing layer.

  Conventionally, as a thermoplastic resin used in this seal ring, Patent Document 1 describes a copolymer of ethylene and vinyl acetate or an ethylene-acrylate copolymer, and Patent Document 2 describes a polyolefin grafted with an unsaturated carboxylic acid. The use of resin has been proposed.

JP 2005-526185 A JP-A-2-293278

The seal ring includes
(1) It melts under relatively low temperature conditions such as a baking process after painting provided in a manufacturing process of a chassis or the like, and exhibits adhesiveness.
(2) Adhesive strength and durability that do not cause problems such as peeling even during long-term use.
(3) To cope with production automation, seal rings do not adhere to each other (mutual fusion) or stacking even in a high temperature environment such as summer. That is, finger touch adhesiveness is low.
Such performance is required.

  However, conventionally, as a thermoplastic resin material used for the seal ring, no study has been made on a resin compounding design that satisfies the above performances (1) to (3), and an improvement is desired. That is, as a thermoplastic resin used for the seal ring, even when an ethylene and vinyl acetate copolymer or ethylene-acrylate copolymer described in Patent Document 1 is used, a polyolefin grafted with an unsaturated carboxylic acid described in Patent Document 2 is used. Even in the case of using a resin, a sufficient material has not been obtained in terms of adhesiveness under low-temperature conditions, peelability during long-term use, and finger-tackiness.

  Accordingly, an object of the present invention is to provide a molded body and a hole plug seal ring that satisfy the performances (1) to (3).

  As a result of intensive studies to solve the above problems, the present inventors use a modified ethylene polymer obtained by grafting an unsaturated carboxylic acid and / or a derivative thereof to an ethylene-α-olefin copolymer having specific properties. Thus, it was found that the required performance can be satisfied, and the present invention has been completed.

  The present invention has been achieved on the basis of such findings, and the gist thereof is as follows.

[1] A copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms, and having an Mw / Mn of 4.0 or less, an unsaturated carboxylic acid and / or a derivative thereof Resin member (I) containing a modified ethylene copolymer (a) obtained by grafting one type of monomer (hereinafter, this monomer is referred to as “graft monomer”), a metal member and / or the resin member A molded body comprising a resin member (II) other than (I), wherein the resin member (I) has a melting point of 50 to 110 ° C. and 0.03 to 2% by weight of the component derived from the graft monomer. A molded article characterized by containing.

[2] The molded product according to [1], wherein the resin constituting the resin member (I) further contains an ethylene copolymer (b).

[3] In [1] or [2], the laminate has at least a layer made of the resin member (I) and a layer made of the metal member and / or the resin member (II). To be molded.

[4] A molded body according to [3], comprising a hole plug body, a plate-like member having an opening, and a hole plug seal ring provided between the hole plug and the plate-like member. The molded body, wherein the hole plug seal ring is a layer made of the resin member (I), and the plate-like member is a layer made of the metal member and / or the resin member (II).

[5] A copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms, and having an Mw / Mn of 4.0 or less, an unsaturated carboxylic acid and / or a derivative thereof Contains a modified ethylene copolymer (a) obtained by grafting one type of monomer (hereinafter, this monomer is referred to as “graft monomer”), having a melting point of 50 to 110 ° C. and a component derived from the graft monomer A hole plug seal ring comprising a resin member (I) containing 0.03 to 2% by weight.

  The resin member (I) included in the molded body of the present invention and the resin member (I) constituting the seal plug for hole plug of the present invention are melted at a relatively low temperature such as 120 ° C. In addition to exhibiting high adhesiveness to the coating material, the adhesive durability is also excellent. On the other hand, the adhesiveness to the touch is low (hereinafter, this performance is referred to as “low-touch adhesiveness”), and there is no problem of mutual adhesion between the resin members (I).

  Therefore, according to the molded body and the hole plug seal ring of the present invention, a hole plug structure having high adhesive strength and excellent long-term durability can be realized with high productivity.

It is typical sectional drawing which shows an example of the structure and usage method of a hole plug.

  Embodiments of the molded body and hole plug seal ring of the present invention will be described in detail below.

  The molded article of the present invention is a copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms, and an ethylene copolymer having Mw / Mn of 4.0 or less is added to an unsaturated carboxylic acid and / or A resin member (I) containing a modified ethylene copolymer (a) obtained by grafting at least one monomer of the derivative (hereinafter referred to as “graft monomer”), a metal member, and / or Or a molded body comprising a resin member (II) other than the resin member (I), wherein the resin member (I) has a melting point of 50 to 110 ° C. and a component derived from the graft monomer of 0.03 It is characterized by containing ˜2% by weight.

  The seal plug for a hole plug according to the present invention is characterized by comprising such a resin member (I).

The resin constituting the resin member (I) according to the present invention (hereinafter referred to as “the resin member (I) of the present invention”) contains the above-described modified ethylene copolymer (a), preferably Further, the modified ethylene copolymer (a) contains an ethylene copolymer (b) and / or a thermoplastic elastomer (c) different from the modified ethylene copolymer (a).
Here, the “ethylene-based copolymer” refers to a copolymer in which 50 mol% or more of all structural units constituting the copolymer is a structural unit derived from ethylene. In the present invention, the ethylene copolymer (b) means an ethylene copolymer other than the modified ethylene copolymer (a).

  In addition, in the resin which comprises the resin member (I) of this invention, in the range which does not impair the effect of this invention, a modified ethylene type copolymer (a), an ethylene type copolymer (b), and a thermoplastic elastomer ( In addition to c), various additives commonly used in ordinary resin compositions such as heat stabilizers, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, rust preventives, pigments, etc. Two or more kinds may be added and used.

  Further, the resin constituting the resin member (I) of the present invention includes a modified ethylene copolymer (a), an ethylene copolymer (b), and a thermoplastic elastomer (within a range not impairing the effects of the present invention). Resin components commonly used in general thermoplastic resin compositions other than c) may be blended. Examples of such resin components include polystyrene resin, polyvinyl chloride resin, polyester resin, polyamide resin, and acrylic resin. And petroleum resin.

[Modified ethylene copolymer (a)]
First, the modified ethylene copolymer (a), which is an essential component of the resin constituting the resin member (I) of the present invention, will be described.

This modified ethylene copolymer (a) grafts at least one monomer (graft monomer) of an unsaturated carboxylic acid and / or a derivative thereof onto a copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms. It is something to be made.
Hereinafter, this ethylene copolymer before graft modification is referred to as “ethylene copolymer (a ′)”.

<Ethylene copolymer (a ')>
The ethylene-based copolymer (a ′) is a copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms.
By introducing an α-olefin as a copolymerization component into the ethylene copolymer (a ′), it is possible to control crystallinity and impart flexibility, as well as impact resistance and tear resistance due to increased molecular entanglement. Although the effect of improvement is produced, when the carbon number of the α-olefin is excessively large, a difference in reactivity with ethylene during polymerization is increased, and productivity and random polymerizability are lowered. When the α-olefin has 8 or less carbon atoms, the above-described characteristics can be obtained without greatly affecting productivity, which is preferable. The α-olefin may be linear or may have a branched chain, but is preferably linear from the viewpoint of production cost. The number is particularly preferably 3 or more and 6 or less.

  The ratio of the structural unit derived from ethylene and the structural unit derived from α-olefin constituting the ethylene-based copolymer (a ′) is preferably a suitable density, MFR and Mw / of the ethylene-based copolymer (a ′) described later. Although it is arbitrary in the range satisfying Mn, usually, the ethylene-derived constitutional unit occupying in all the constitutional units constituting the ethylene copolymer (a ′) is 50 mol% or more, and the upper limit is usually 98 mol%. It is as follows.

  Such an ethylene-based copolymer (a ′) can be selected from those produced using a Ziegler-Natta catalyst, a chromium catalyst, a vanadium catalyst, a metallocene catalyst, or the like.

In the present invention, the density of the ethylene copolymer (a ′) is usually 0.860 g / cm ³ or more, preferably 0.880 g / cm ³ or more, and usually less than 0.910 g / cm ³ , preferably 905 g / cm ^{3. 3} or less. When the density of the ethylene copolymer (a ′) is not less than the above lower limit, good low-tactile tackiness can be obtained, and when the density is less than the above upper limit, good low-temperature adhesiveness can be obtained. Can be obtained.

  The density of the ethylene copolymer (a ′) can be measured by an underwater substitution method in JIS-K7112. The same applies to the density of the ethylene copolymer (b) described later.

  In the present invention, the MFR of the ethylene copolymer (a ′) is usually 0.1 g / 10 min or more, preferably 0.5 g / 10 min or more, and usually 50 g / 10 min or less, preferably 30 g / 10. Is less than a minute. When the MFR is not less than the above lower limit and not more than the above upper limit, high adhesive strength can be obtained.

  Here, the MFR of the ethylene copolymer (a ′) is a value measured at a temperature of 190 ° C. and a load of 21.2 N in accordance with JIS-K6922. The same applies to the MFR of the modified ethylene copolymer (a) described later and the MFR of the resin constituting the resin member (I).

  Further, Mw / Mn of the ethylene copolymer (a ′) is usually 1.0 or more and 4.0 or less, preferably 3.5 or less, more preferably 3.0 or less. When Mw / Mn is within the above range, high adhesive strength can be obtained, but when Mw / Mn exceeds the upper limit, the adhesive strength is deteriorated.

  Here, the molecular weight distribution Mw / Mn (weight average molecular weight Mw / number average molecular weight Mn) of the ethylene copolymer (a ′) is measured by the GPC (gel permeation chromatography) method under the following apparatus and conditions. Value.

Apparatus: “GPCV2000” manufactured by Waters
Detector: RI
Mobile phase: o-dichlorobenzene Column: TSKgel GMH6-HT (30 cm × 4)
Column temperature: 135 ° C
Calibration sample: Monodisperse polystyrene Calibration method: Polyethylene conversion (general-purpose calibration curve)

  The ethylene copolymer (a ′) has a weight average molecular weight (Mw) of usually 20000 or more, preferably 30000 or more, and usually 250,000 or less, preferably 200000 or less. When the weight average molecular weight (Mw) of the ethylene copolymer (a ′) is within the above range, high adhesive strength can be obtained.

<Unsaturated carboxylic acid and / or derivative thereof>
The unsaturated carboxylic acid and / or derivative thereof graft-polymerized to the ethylene copolymer (a ′) is usually those having 3 or more carbon atoms, preferably 4 or more and usually 10 or less, specifically Examples thereof include unsaturated carboxylic acids such as acrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid and crotonic acid, and anhydrides and esters thereof.

  These may be used individually by 1 type and may use 2 or more types together by arbitrary ratios and combinations.

  Among these, maleic acid, maleic anhydride, or a mixture containing these as a main component is preferable. In particular, maleic anhydride is inexpensive and easily available, and is high by grafting to the ethylene-based copolymer (a ′). It is preferable because it exhibits adhesiveness.

  The method for graft modification of the aforementioned ethylene copolymer (a ′) with an unsaturated carboxylic acid and / or derivative thereof is not limited, and the ethylene copolymer (a ′), unsaturated carboxylic acid and / or derivative thereof, And a melting method in which the radical initiator is kneaded in a molten state using an extruder, a Banbury mixer, a kneader, etc .; an ethylene copolymer (a ′), an unsaturated carboxylic acid and / or a derivative thereof, and a radical initiator A solution method in which it is dissolved in an appropriate solvent; a slurry method in which an unsaturated carboxylic acid and / or a derivative thereof and a radical initiator are allowed to act in a state where particles of the ethylene copolymer (a ′) are suspended. Or a so-called gas phase grafting method.

  Examples of radical initiators 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, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane-3, lauroyl peroxide, t-butylperoxybenzoate 1 type, or 2 or more types of organic peroxides, such as these, are mentioned.

  The amount of the unsaturated carboxylic acid and / or its derivative (graft monomer) to be grafted to the ethylene copolymer (a ′), that is, the unsaturated carboxylic acid as a graft monomer to the ethylene copolymer (a ′). And / or the proportion of the structural unit derived from the graft monomer in the modified ethylene copolymer (a) obtained by grafting the derivative thereof (hereinafter referred to as “addition amount”) is the modified ethylene copolymer (a ) Content of the component derived from the graft monomer contained in the resin member (I) (hereinafter referred to as “graft monomer amount”) is usually 0.03% by weight or more, preferably 0.05% by weight or more, The amount is usually 2% by weight or less, preferably 1.5% by weight or less. When the addition amount and the amount of graft monomer are less than the above lower limit, the adhesive strength is inferior, and when the amount exceeds the upper limit, the thermal stability is inferior.

  This addition amount and graft monomer amount can be determined by measuring the absorption specific to the carboxylic acid or its derivative in the resin using an infrared absorption spectrum method.

The MFR of the modified ethylene copolymer (a) obtained by grafting the unsaturated carboxylic acid and / or derivative thereof to the ethylene copolymer (a ′) is usually 0.6 g / 10 min or more, preferably It is 1.0 g / 10 min or more, usually 30 g / 10 min or less, preferably 25 g / 10 min or less. When the MFR of the modified ethylene copolymer (a) is within the above range, high adhesive strength can be obtained.
In addition, it is preferable that resin which comprises the resin member (I) of this invention contains 10 weight% or more of modified ethylene-type copolymer (a), especially 20 weight% or more.

[Ethylene copolymer (b)]
Next, the ethylene copolymer (b) preferably contained in the resin constituting the resin member (I) of the present invention will be described.

Although there is no restriction | limiting in particular as this ethylene-type copolymer (b), The following are mentioned, These may be used individually by 1 type and may use 2 or more types together by arbitrary ratios and combinations. May be.
-Ethylene-α-olefin copolymer (b1) of ethylene and α-olefin having 3 or more carbon atoms
・ Low density polyethylene (b2) manufactured by high pressure method
・ Ethylene homopolymer (b3)
・ Ethylene-vinyl acetate copolymer (b4)

  Hereinafter, each ethylene copolymer (b) will be described.

<Low density polyethylene (b1) manufactured by high pressure method>
As the low density polyethylene (b1) produced by the high pressure method, a catalyst such as a Ziegler-Natta catalyst, a chromium catalyst, a vanadium catalyst, or a metallocene catalyst is used by using one or more of ethylene and an α-olefin having 3 or more carbon atoms. The α-olefin, which is a copolymerization component of the ethylene-α-olefin copolymer (b1), usually has 3 or more carbon atoms and usually 8 or less carbon atoms. Preferably, 6 or less are mentioned. The α-olefin may be linear or branched, but is preferably linear from the viewpoint of production cost.

  The ratio of the structural unit derived from ethylene and the structural unit derived from α-olefin constituting the ethylene-α-olefin copolymer (b1) is a suitable density of the ethylene-α-olefin copolymer (b1) described later and Although it is arbitrary as long as the melting point is satisfied, the ethylene-derived structural unit occupying all the structural units constituting the ethylene-α-olefin copolymer (b1) is usually 50 mol% or more, and the upper limit is usually 98 mol. % Or less.

The ethylene-α-olefin copolymer (b1) can be blended with the modified ethylene copolymer (a) to satisfy suitable physical properties of the resin constituting the resin member (I) of the present invention described later. There are no particular limitations on the physical properties and the like, but the density is usually 0.860 g / cm ³ or more, usually less than 0.910 g / cm ³ , preferably 0.905 g / cm ³ or less, more preferably Is 0.900 g / cm ³ or less, and the melting point measured by DSC (differential scanning calorimeter) is usually 50 ° C. or higher, preferably 55 ° C. or higher, more preferably 58 ° C. or higher, and usually 110 ° C. or lower, preferably It is 105 ° C. or lower, more preferably 100 ° C. or lower.

  When the ethylene-α-olefin copolymer (b1) satisfies the above density and melting point, the low-temperature adhesiveness and low finger-tackiness of the resin member (I) of the present invention become even more preferable.

  In addition, the measuring apparatus and conditions of melting | fusing point by DSC of an ethylene-alpha-olefin copolymer (b1) are as follows. The same applies to the melting point of the ethylene copolymer (b2) described later, the melting point of the thermoplastic elastomer (c), and the melting point of the resin.

Equipment: “DSC6220” manufactured by Seiko Eye Co., Ltd.
Detector: DSC
Temperature increase / decrease rate: Primary temperature increase from 40 ° C to 170 ° C 100 ° C / min
Cooling 170 ° C to -10 ° C -10 ° C / min
Secondary temperature rise −10 ° C. to 170 ° C. 10 ° C./min Melting point calculation: The peak top temperature at the secondary temperature rise is taken as the melting point.

  The said ethylene-alpha-olefin copolymer (b1) may be used individually by 1 type, and may use 2 or more types together by arbitrary ratios and combinations.

<Low density polyethylene (b2) manufactured by high pressure method>
The low-density polyethylene (b2) produced by the high-pressure method can be selected from those produced by existing equipment such as a tubular or vessel reactor, and the physical properties thereof can be selected from the modified ethylene copolymer (a ) And is not particularly limited as long as it can satisfy the suitable physical properties of the resin constituting the resin member (I) of the present invention described later, and the density is usually 0.910 g / cm ³ or more, preferably 0.913 g / cm ³ or more, more preferably 0.915 g / cm ³ or more, typically 0.930 g / cm ³ or less, preferably 0.928 g / cm ³ or less, more preferably 0.925 g / cm ³ The melting point measured by DSC is usually 90 ° C. or higher, preferably 95 ° C. or higher, more preferably 100 ° C. or higher, and usually 125 ° C. or lower, preferably 120 ° C. or lower. Ku is less than or equal to 115 ℃.

  When the low-density polyethylene (b2) produced by the high-pressure method satisfies the above density and melting point, the low-temperature adhesiveness and low-tactile tackiness of the resin member (I) of the present invention become even more preferable.

  The low density polyethylene (b2) produced by the high pressure method may be used alone or in combination of two or more in any ratio and combination.

<Ethylene homopolymer (b3)>
The physical properties of the ethylene homopolymer (b3) can be blended with the modified ethylene copolymer (a) to satisfy the suitable physical properties of the resin constituting the resin member (I) of the present invention described later. There is no particular limitation.

  The said ethylene homopolymer (b3) may be used individually by 1 type, and may use together 2 or more types from which molecular weight, a branching degree, the catalyst to manufacture, a manufacturing method, etc. differ by arbitrary ratios and combinations.

<Ethylene-vinyl acetate copolymer (b4)>
The ethylene-vinyl acetate copolymer (b4) can be selected from those produced by existing equipment such as a tubular or vessel reactor, and is derived from ethylene constituting the ethylene-vinyl acetate copolymer (b4). The proportion of units and vinyl acetate-derived structural units is usually 50 mol% or more, preferably 60 mol%, of ethylene-derived structural units occupying all the structural units constituting the ethylene-vinyl acetate copolymer (b4). The upper limit is usually 90 mol% or less, preferably 85 mol% or less.

  The physical properties of the ethylene-vinyl acetate copolymer (b4) satisfy the preferred physical properties of the resin constituting the resin member (I) of the present invention described later by blending it with the modified ethylene copolymer (a). There is no particular limitation as long as it can be obtained.

  The said ethylene-vinyl acetate copolymer (b4) may be used individually by 1 type, and may use together 2 or more types from which molecular weight, a copolymerization ratio, etc. differ by arbitrary ratios and combinations.

[Thermoplastic elastomer (c)]
Next, the thermoplastic elastomer (c) that can be contained in the resin constituting the resin member (I) of the present invention will be described.

The thermoplastic elastomer (c) is an ethylene copolymer elastomer (ethylene-propylene copolymer, ethylene-butene copolymer, in which less than 50 mol% of all the structural units constituting the copolymer is a structural unit derived from ethylene, Ethylene-octene copolymer), propylene-butene copolymer, ternary / quaternary copolymer containing ethylene and / or propylene, styrene binary / ternary copolymer such as SBS, water An additive, polyisobutylene, butyl rubber, butadiene rubber, or isoprene rubber can be selected from those manufactured by existing equipment. The physical properties are not particularly limited as long as they can be blended with the modified ethylene copolymer (a) to satisfy the suitable physical properties of the resin constituting the resin member (I) of the present invention described later. However, the density is usually 0.86 g / cm ³ or more, usually 0.90 g / cm ³ or less, preferably 0.89 g / cm ³ or less, more preferably 0.88 g / cm ³ or less, and DSC The melting point measured by is usually 20 ° C. or higher, preferably 25 ° C. or higher, more preferably 30 ° C. or higher, and usually 125 ° C. or lower, preferably 115 ° C. or lower, more preferably 110 ° C. or lower.

  When the thermoplastic elastomer (c) satisfies the above density and melting point, the low-temperature adhesiveness and low finger-tackiness of the resin member (I) of the present invention become even more preferable.

  The said thermoplastic elastomer (c) may be used individually by 1 type, and may use 2 or more types together by arbitrary ratios and combinations.

[Resin constituting the resin member (I)]
The resin constituting the resin member (I) of the present invention is mainly composed of the modified ethylene copolymer (a), and if necessary, the ethylene copolymer (b) and / or the thermoplastic elastomer (c), Furthermore, it is formed by blending resin components other than the aforementioned additives for various resins and the modified ethylene copolymer (a), the ethylene copolymer (b) and the thermoplastic elastomer (c). The resin composition usually has an MFR of 0.5 g / 10 min or more, preferably 1 g / 10 min or more, more preferably 3 g / 10 min or more, and usually 30 g / 10 min or less, preferably 27 g / 10 min or less. The content of the structural unit derived from the unsaturated carboxylic acid and / or derivative thereof grafted on the modified ethylene copolymer (a) in the resin member (I) as described above, preferably at 25 g / 10 min or less. (Graph Monomer amount) is usually 0.03 wt% or more, preferably 0.05 wt% or more, more preferably 0.1 wt% or more, usually 2 weight% or less, preferably 1.5 wt% or less.

  When the MFR of the resin constituting the resin member (I) is within the above range, high adhesive strength can be obtained.

  Further, when the amount of the graft monomer is not less than the above lower limit, sufficient adhesive strength can be obtained, and when it is not more than the above upper limit, the thermal stability becomes excellent.

  The blending amount of the ethylene copolymer (b) and / or the thermoplastic elastomer (c) in the resin composition is arbitrary as long as the above physical properties can be obtained, and the ethylene copolymer (b) to be used is used. And / or as appropriate depending on the type of the thermoplastic elastomer (c), the physical properties of the modified ethylene copolymer (a), etc. In order to effectively obtain finger-tackiness, the total amount of the ethylene copolymer (b) and the thermoplastic elastomer (c) in the resin member (I) with respect to the modified ethylene copolymer (a) is It is preferably 90% by weight or less, particularly 80% by weight or less. In addition, when using an ethylene-type copolymer (b) and a thermoplastic elastomer (c) together, the mixture ratio is arbitrary.

  The resin constituting the resin member (I) has a melting point measured by DSC of usually 50 ° C. or higher, preferably 60 ° C. or higher, and usually 110 ° C. or lower, preferably 105 ° C. or lower. Here, the melting point of the resin constituting the resin member (I) indicates the maximum peak height among the melting points indicated by DSC. When the melting point is less than the above range, the adhesiveness to the touch is inferior, and when it exceeds the above range, the adhesive strength is inferior. When the melting point is equal to or higher than the lower limit, the low-tactile adhesiveness is excellent, and when the melting point is equal to or lower than the upper limit, the low-temperature adhesiveness is excellent. Here, the DSC measurement conditions are the same as those described above.

The melting point of the resin constituting the resin member (I) will be described in more detail.
When the resin constituting the resin member (I) contains the modified ethylene copolymer (a) and the ethylene copolymer (b), the melting point is usually detected from a plurality of peaks derived from each. . In that case, the melting point of the resin constituting the resin member (I) means the peak top temperature having the maximum peak height among these.
That is, even if the melting point derived from the modified ethylene copolymer (a) satisfies the temperature range, the ethylene copolymer (b) having a higher peak height does not satisfy the temperature range. However, even if the modified ethylene copolymer (a) does not satisfy the temperature range, the ethylene copolymer (b) having a higher peak height is in the temperature range. If the above is satisfied, the target performance of the present application can be obtained.

  The above-mentioned resin constituting the resin member (I) of the present invention is an ethylene copolymer (b) and / or a thermoplastic elastomer (c) blended into the modified ethylene copolymer (a) as necessary. The other additives and resin components can be prepared by melt-kneading according to a conventional method.

[Metal member and / or other resin member (II) other than the resin member (I)]
Next, the metal member and / or the resin member (II) other than the resin member (I) constituting the molded body of the present invention will be described.

  The metal member is not particularly limited, but is generally a member constituting a plate-like member such as the aforementioned chassis, and a member made of stainless steel, cold-rolled steel plate, various plated steel plates, aluminum material, or the like. Can be mentioned.

  In addition, as the resin member (II) other than the resin member (I), a material used by being superimposed on such a metal member is exemplified, and a member made of a resin selected from polyamide resin, polyester, polyethylene, polypropylene and the like Is mentioned.

[Hole plug structure]
More specifically, in the molded article of the present invention, the resin member (I) of the present invention constitutes a hole plug seal ring, and the metal member and / or another resin member other than the resin member (I) ( II) comprises a base material for a plate-like member such as a chassis or a coating layer applied thereon, and a laminate in which a hole plug structure is formed. The resin member (I) of the present invention Due to the low finger touch, low temperature adhesion, high adhesive strength, and durability of the adhesion, a hole plug structure excellent in sealing effect can be provided.
The shape of the hole plug structure is typically shown in FIG. 1, but is not limited to that shown in FIG.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

[Evaluation methods]
Evaluation methods for various physical properties and characteristics in the following examples and comparative examples are as follows.

<Molecular weight and molecular weight distribution>
Measurement was performed by GPC with the following apparatus and conditions.
Apparatus: “GPCV2000” manufactured by Waters
Detector: RI
Mobile phase: o-dichlorobenzene Column: TSKgel GMH6-HT (30 cm × 4)
Column temperature: 135 ° C
Calibration sample: Monodisperse polystyrene Calibration method: Polyethylene conversion (general-purpose calibration curve)

<Melting point>
It was measured by DSC with the following apparatus and conditions.
Equipment: “DSC6220” manufactured by Seiko Eye Co., Ltd.
Detector: DSC
Temperature increase / decrease rate: Primary temperature increase from 40 ° C to 170 ° C 100 ° C / min
Cooling 170 ° C to -10 ° C -10 ° C / min
Secondary temperature rise −10 ° C. to 170 ° C. 10 ° C./min Melting point calculation: The peak top temperature at the secondary temperature rise was taken as the melting point.

<MFR>
According to JIS-K6922, the temperature was 190 ° C. and the load was 21.2 N.

<Density>
According to JIS-K7112, it measured by the underwater substitution method.

<Addition amount, graft monomer amount>
Using infrared absorption spectrum method, it was determined from the characteristic absorption of carboxylic acid or its derivative in the resin.
Apparatus: JASCO Corporation FT / IR610
Carbonyl absorption: 1900-1600 cm ^-1 (C = O stretching vibration band)

<Adhesive strength>
Using a compression molding machine, a resin press sheet (200 × 100 × 2 mm) was prepared under the conditions of 200 ° C., 6 minutes, and 10 MPa pressure. The obtained resin sheet was layered on the substrate to be worn, preheated at each test temperature for 8 minutes, and then heated and bonded for 2 minutes under the condition of 1 MPa pressure.
As the substrate to be worn, a cold-rolled steel sheet (referred to as “substrate to be worn 1”) frequently used for automobile bodies and parts and 66 nylon composite material containing 30% by weight of an amino group-treated glass filler. (Referred to as “substrate 2 to be worn”). The sizes of the substrate 1 to be worn are 150 × 70 × 0.8 mm, the substrate 2 to be worn is 70 × 70 × 2 mm, and the test temperatures of the substrate 1 to be worn and the substrate 2 to be worn (when preheating is performed). In all cases, the temperature was 115 ° C.

These substrates 1 and 2 were subjected to an adhesion test after cleaning their surfaces with petroleum benzine.
After cutting into the resin sheet surface of the obtained heat-bonded sample with a width of 10 mm to the depth at which the resin sheet layer is divided, the heat-bonded sample for the 10 mm width is peeled by 90 ° using a tensile tester. The adhesion strength between the resin sheet and the substrate 1 to be worn or the substrate 2 to be worn was measured under the conditions of 10 mm / min.

<Touch adhesion>
The resin sheet prepared in the above measurement of the adhesive strength is kept in an oven at 35 ° C. for 12 hours, and the presence or absence of finger-tacking is determined for the sheet immediately after taking out (rubbing the sheet surface with a finger to confirm the presence or absence of sticking to the finger )did.

[Modified ethylene copolymer]
The modified ethylene copolymer used in Examples and Comparative Examples was produced by the following method.

<Production Example 1: Production of modified ethylene copolymer (a-1)>
Ethylene-1-hexene copolymer (MFR = 16 g / 10 min, density = 0.90 g / cm ³ , Mw / Mn = 2.2, Mw = 51000) was added with 1.3% by weight of maleic anhydride, 2% , 5-dimethyl-2,5-t-butylperoxyhexane, 0.065% by weight, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane Is added to a biaxial kneader and melt-kneaded at a resin temperature of 260 ° C. so that the MFR is 8 g / 10 minutes and the added amount is 1.0% by weight. Maleic anhydride graft-modified ethylene-1-hexene copolymer (modified ethylene copolymer (a-1)) was obtained.

<Production Example 2: Production of Modified Ethylene Copolymer (a-2)>
Ethylene-1-butene copolymer (MFR = 3 g / 10 minutes, density = 0.88 g / cm ³ , Mw / Mn = 2.3, Mw = 83000), 0.6% by weight of maleic anhydride, -T-butyl-peroxy t-diisopropylbenzene was added in an amount of 0.03% by weight, premixed with a Henschel mixer, supplied to a single-screw kneader, and melt-kneaded at a resin temperature of 240 ° C., resulting in an MFR of 1. A maleic anhydride graft-modified ethylene-1-butene copolymer (modified ethylene copolymer (a-2)) having an addition amount of 0.4 wt% was obtained at 6 g / 10 min.

<Production Example 3: Production of modified ethylene copolymer (a-3)>
Ethylene-1-butene copolymer (MFR = 2 g / 10 min, density = 0.92 g / cm ³ , Mw / Mn = 4.2, Mw = 101000), 1.0 wt% maleic anhydride, 0.05% by weight of t-butyl peroxide, 0.01% by weight of tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, Add 0.02% by weight of stearyl (3,5-di-t-butyl-4-hydroxyphenyl) propionate, pre-mix with Henschel mixer, supply to single-screw kneader, melt at resin temperature 230 ° C By kneading, a maleic anhydride graft-modified ethylene-1-butene copolymer (modified ethylene copolymer (a-3)) having an MFR of 0.56 g / 10 min and an addition amount of 0.8% by weight is obtained. It was.

[Ethylene copolymer]
As the ethylene copolymer to be blended with the modified ethylene copolymer, the resins shown in Table 1 below were used. In addition, all are commercial items and are not modified.

[Examples 1-8, Comparative Examples 1-7]
Tetrakis [methylene-3- (3 ′, 5 ′), which is an antioxidant, with respect to 100 parts by weight of the resin component obtained by blending the modified ethylene copolymer and the ethylene copolymer at the ratio shown in Table 2. -Di-t-butyl-4'-hydroxyphenyl) propionate] 0.05 parts by weight of methane and 0.05 parts by weight of tri (2,4-di-t-butylphenyl) phosphite are added and uniaxially kneaded. A resin sample was obtained by melt kneading at a resin temperature of 210 ° C. using a machine. Table 2 shows the evaluation results of the MFR, graft monomer amount, melting point obtained by DSC measurement, adhesion strength and finger tackiness of the obtained resin sample.

  From Table 2, in Examples 1-8 which satisfy the requirements of the present invention, in addition to being excellent in low finger-tackiness, it has good adhesive strength at low temperature heating against cold rolled steel sheets and 66 nylon composites. Although obtained, the ethylene-vinyl acetate copolymer described in Patent Document 1 (Comparative Examples 3 and 4), the resin described in Patent Document 2 (Comparative Examples 1 and 2) and does not satisfy the requirements of the present invention In the resin composition (Comparative Examples 5 and 6), the adhesive strength was clearly low.

The resin member (I) contained in the molded article of the present invention and the resin member (I) constituting the seal plug for hole plug of the present invention are excellent in finger-tackiness and heat bonding conditions at a low temperature of 120 ° C. or lower In addition, it is possible to reduce the size of the heating furnace in the heat bonding process for general-purpose parts, and the heat capacity of automobile chassis is large and the heating rate is slow in the heating furnace. Thermal bonding to the parts becomes easy. In addition, since a high adhesive strength can be obtained at a low temperature to a substrate having an amino group such as 66 nylon, it can also be used for adhesion to a cationic electrodeposition coating surface, which is an undercoating step.
Taking advantage of such features, the present invention is effectively applied to various hole plug structures.

DESCRIPTION OF SYMBOLS 1 Plate-shaped member 2 Opening 3 Hole plug main body 4 Seal ring 5 Base part 6 Protrusion part 10 Hole plug

Claims (5)

  An ethylene-based copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms having an Mw / Mn of 4.0 or less, and at least one of unsaturated carboxylic acid and / or a derivative thereof; Resin member (I) containing a modified ethylene copolymer (a) obtained by grafting a monomer (hereinafter, this monomer is referred to as “graft monomer”), a metal member and / or the resin member (I) The resin member (I) is a molded body containing other resin member (II) other than the above, and the resin member (I) has a melting point of 50 to 110 ° C. and contains 0.03 to 2% by weight of the component derived from the graft monomer. A molded product characterized by.   2. The molded body according to claim 1, wherein the resin constituting the resin member (I) further contains an ethylene copolymer (b).   3. The molded body according to claim 1, wherein the molded body is a laminate having at least a layer made of the resin member (I) and a layer made of the metal member and / or the resin member (II).   The molded body according to claim 3, comprising a hole plug main body, a plate-like member having an opening, and a hole plug seal ring provided between the hole plug and the plate-like member. A molded body, wherein the plug seal ring is a layer made of the resin member (I), and the plate-like member is a layer made of the metal member and / or the resin member (II).   An ethylene-based copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms having an Mw / Mn of 4.0 or less, and at least one of unsaturated carboxylic acid and / or a derivative thereof; It contains a modified ethylene copolymer (a) obtained by grafting a monomer (hereinafter, this monomer is referred to as “graft monomer”), and has a melting point of 50 to 110 ° C. A seal ring for a hole plug comprising the resin member (I) containing 03 to 2% by weight.

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