JP2018090688A - Thermoplastic resin composition for composite molding and composite molding using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite molding integrated with a thermoplastic resin to metal, and is integrated by direct heat fusion of the thermoplastic resin to the metal due to high adhesion to metal of the thermoplastic resin without subjected to pre-treatment such as primer treatment.SOLUTION: A thermoplastic resin composition for molding at least a contact part with metal of a thermoplastic resin part of a composite molding obtained by integration of the metal with the thermoplastic resin part contains at least the following component (a) and the following component (b), where at least one is graft-modified with α,β- ethylenically unsaturated carboxylic acid. component (a): aromatic polyester-based thermoplastic elastomer. component (B): aromatic vinyl hydrocarbon-conjugated diene copolymer and/or its hydrogenated product.SELECTED DRAWING: None

Description

  The present invention relates to a thermoplastic resin composition for a composite molded product used as a molding material for a thermoplastic resin part of a composite molded product in which a metal and a thermoplastic resin are integrated, and the thermoplastic resin composition for the composite molded product. The present invention relates to a composite molded article using a product.

  Specifically, the present invention relates to a thermoplastic resin composition for a composite molded article obtained by thermally fusing a thermoplastic resin to the surface of a metal substrate such as a steel sheet, and composite molding using the thermoplastic resin composition. Related to goods. More specifically, the present invention relates to an economical and high value-added metal obtained by integrating a thermoplastic resin on a surface of a heated metal base material by means of a production engineering such as heat fusion, which is extremely efficient in terms of production engineering. The present invention relates to a thermoplastic resin composition for a thermoplastic resin composite molded article and a composite molded article using the thermoplastic resin composition.

  Conventionally, various products made of metal (hereinafter, this term should be interpreted in the broadest sense as including materials, intermediate products, and final products. In this specification, “metal” means an alloy. Various coating agents (coating agents) are applied to the surface of metal products from the viewpoints of surface protection and decoration. The coating agent includes a polymer solvent type and an aqueous type. In general, the coating film after the coating treatment is baked, and a polymer (resin) component in the coating agent is crosslinked or cured to form a surface layer.

  The solvent-type coating agents (solution type, dispersion type) described above use various organic solvents, and thus cost is required because measures are taken in terms of environment and occupational health. In addition, aqueous coating agents (aqueous solution type and aqueous dispersion type) have problems in terms of energy saving such as drying of the coating film.

  In addition, the solvent-type and aqueous-type coating methods described above have a problem in that, for example, when the configuration or color of the coating film is switched, labor is required for the production line cleaning work and the like, resulting in an increase in cost. Furthermore, the above-mentioned solvent type and aqueous type coating methods require energy costs for the operation of a drying furnace, a baking furnace, etc. when baking is performed after the coating process. There are high cost factors such as high capital investment required for the collection equipment.

  In addition to the solvent type and aqueous type coating methods described above, a powder coating method is also known in the art. In this powder coating method, generally, a granular coating agent is electrostatically sprayed on the surface of the substrate, and then the coating agent is melt-processed to form a continuous coating layer on the surface of the substrate.

  In this powder coating method, a coating agent applied to an automotive exterior board or the like is generally a polymer material having a high melt viscosity and a high glass transition temperature (Tg), such as a thermosetting polyester resin or a thermosetting epoxy resin. Or a cross-linked acrylic resin or the like. In this powder coating agent, the reason why a high glass transition temperature (Tg) is desirable is that the higher the glass transition temperature (Tg), the higher the hardness of the coating film, and the easier manufacture and application of the coating agent. This is for a reason. In the powder coating agent described above, the reason why a low glass transition temperature (Tg) can be avoided is that when the glass transition temperature (Tg) is low, there is a tendency to exhibit tackiness and to aggregate during storage. This is to clog the gun and reduce the workability of spray painting.

  In addition, in the industry, when forming a coating of a polymer resin film on a metal substrate, in order to increase the adhesion strength of the coating, the adhesive layer or the primer layer and the adhesive layer are used on the metal substrate. It is well known to form a resin film coating. However, these methods require an adhesive coating treatment or a primer treatment and an adhesive coating treatment on the metal substrate prior to the formation of the resin film coating. I can't say that.

  Japanese Patent Application Laid-Open No. 2006-213818 discloses a solution of the above problems by using a modified polyester thermoplastic elastomer obtained by graft-modifying a polyester thermoplastic elastomer with an α, β-ethylenically unsaturated carboxylic acid. However, since further improvement of the adhesive strength may be required in practice, further improvement in adhesion to metal is desired.

JP 2006-213818 A

  The present invention further improves the adhesion to metal of the thermoplastic resin composition for composite molded articles proposed in Japanese Patent Application Laid-Open No. 2006-213818, in which the thermoplastic resin is integrated with the metal. In composite molded products, due to the high adhesion of thermoplastic resins to metals, composite molded products in which thermoplastic resin is integrated by direct heat fusion to metal without pretreatment such as primer treatment are provided. The task is to do.

The inventor has conducted extensive studies to solve the above-mentioned problems, and uses an aromatic polyester-based thermoplastic elastomer and an aromatic vinyl hydrocarbon-conjugated diene copolymer and / or a hydrogenated product thereof in combination. It has been found that the use of one of them by graft modification with α, β-ethylenically unsaturated carboxylic acid can further improve the adhesion to metal, and the present invention has been completed.
That is, the gist of the present invention is as follows.

[1] A thermoplastic resin composition for molding at least a contact portion of the thermoplastic resin portion of a composite molded article obtained by integrating a metal and a thermoplastic resin portion with the metal. ) Component and the following (b) component, and one or both of the component (a) and the component (b) are graft-modified with an α, β-ethylenically unsaturated carboxylic acid. A thermoplastic resin composition for composite molded articles.
(A) Component: Aromatic polyester-based thermoplastic elastomer (b) Component: Aromatic vinyl hydrocarbon-conjugated diene copolymer and / or hydrogenated product thereof

[2] In [1], 50 to 90% by mass of component (a) and 10 to 50% by mass of component (b) are contained in a total of 100% by mass of component (a) and component (b). A thermoplastic resin composition for composite molded articles.

[3] The thermoplastic resin composition for composite molded articles according to [1] or [2], wherein the aromatic polyester-based thermoplastic elastomer contains a polyalkylene ether glycol segment.

[4] The thermoplastic resin composition for composite molded articles according to [3], wherein the content of the polyalkylene ether glycol segment in the aromatic polyester-based thermoplastic elastomer is 1 to 80% by mass.

[5] Any of [1] to [4], wherein the aromatic vinyl hydrocarbon-conjugated diene copolymer is a styrene-butadiene-styrene copolymer and / or a styrene-isoprene-butadiene-styrene copolymer. A thermoplastic resin composition for composite molded articles according to claim 1.

[6] The grafting amount of the α, β-ethylenically unsaturated carboxylic acid is 0.01 to 10% by mass with respect to 100% by mass in total of the components (a) and (b). The thermoplastic resin composition for composite molded articles according to any one of the above.

[7] A composite molded article using the thermoplastic resin composition for composite molded articles according to any one of [1] to [6].

[8] The composite molded article according to [7], which includes a metal layer and an adhesive layer, and the adhesive layer includes the thermoplastic resin composition for composite molded articles.

  The thermoplastic resin composition for composite molded articles of the present invention has good adhesion to metal, and can be firmly bonded and integrated on the surface of metal by heat fusion or the like without performing primer treatment. Therefore, a good surface protective layer can be efficiently formed on the metal surface with a simple operation. Moreover, since the thermoplastic resin composition for composite molded articles of the present invention has good adhesion performance to other thermoplastic resins, it is also used as an adhesive resin between metals and other thermoplastic resins. be able to.

  The thermoplastic resin composition for composite molded articles of the present invention is such that the thermoplastic resin composition for composite molded articles of the present invention has excellent adhesion to metal, and further excellent adhesiveness to other thermoplastic resins. , A carboxyl group (—COOH) relative to the component (A) and / or the component (b) contained in the thermoplastic resin composition for composite molded article of the present invention by graft modification with an α, β-ethylenically unsaturated carboxylic acid. ) Is introduced, and the affinity and adhesion to metals and other thermoplastic resins by the carboxyl group and the aromatic vinyl hydrocarbon-conjugated diene copolymer and / or hydrogenated product thereof as component (b) This is thought to be due to the fact that the property and bondability become stronger.

  For this reason, according to the present invention, it is possible to integrate the thermoplastic resin directly on the metal surface by thermal fusion or the like without performing pretreatment such as primer treatment. Industrially superior effects such as the non-use of the processing organic solvent can be obtained.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. However, the description of each constituent element described below is a representative example of embodiments of the present invention, and the present invention is not limited to these unless it exceeds the gist. Is not to be done.

[Thermoplastic resin composition for composite molded article]
The thermoplastic resin composition for a composite molded article of the present invention is a heat for molding at least a contact portion of the thermoplastic resin portion of a composite molded product obtained by integrating a metal and a thermoplastic resin portion with the metal. A plastic resin composition comprising at least the following component (a) and the following component (b), wherein one or both of the component (a) and the component (b) are α, β-ethylenic It is characterized by being graft-modified with a saturated carboxylic acid.
(A) Component: Aromatic polyester-based thermoplastic elastomer (b) Component: Aromatic vinyl hydrocarbon-conjugated diene copolymer and / or hydrogenated product thereof In the present invention, α, β- used for graft modification The ethylenically unsaturated carboxylic acid may be an anhydride of α, β-ethylenically unsaturated carboxylic acid.

  Hereinafter, the component (a) and the component (b) in which at least one of the thermoplastic resin composition for composite molded article of the present invention is graft-modified with an α, β-ethylenically unsaturated carboxylic acid are collectively referred to as “graft”. It may be referred to as “modified elastomer component”.

[Graft-modified elastomer component]
First, the graft-modified elastomer component of the present invention will be described.

  The graft-modified (a) component or (b) component of the graft-modified elastomer component is an α, β-ethylenically unsaturated carboxylic acid, preferably in the presence of a radical generator, and the aromatic polyester of component (a) It is obtained by graft polymerization to a thermoplastic elastomer, or the aromatic vinyl hydrocarbon-conjugated diene copolymer (b) and / or its hydrogenated product.

<(A) Component: Aromatic Polyester Thermoplastic Elastomer>
The aromatic polyester-based thermoplastic elastomer as component (a) is preferably a saturated aromatic polyester-based thermoplastic elastomer, and particularly preferably a saturated aromatic polyester-based thermoplastic elastomer containing a polyalkylene ether glycol segment. .

  The aromatic polyester-based thermoplastic elastomer preferably contains, for example, an aromatic polyester as a hard segment and a polyalkylene ether glycol or an aliphatic polyester as a soft segment, and in particular, a polyalkylene ether glycol as a soft segment. The aromatic polyester polyether block copolymer used is preferred.

  The content of the polyalkylene ether glycol segment in the aromatic polyester-based thermoplastic elastomer is usually 1% by mass or more, preferably 2% by mass or more, more preferably 7% by mass or more, and further preferably 10% by mass or more. Moreover, it is 80 mass% or less normally, Preferably it is 75 mass% or less, More preferably, it is 70 mass% or less, More preferably, it is 65 mass% or less. When the content of the polyalkylene ether glycol segment in the aromatic polyester-based thermoplastic elastomer is too large, sufficient hardness may not be expressed in the resulting molded article, and the mechanical strength may be inferior. If the amount is too small, the elastomeric properties may be lowered, and the flexibility and impact resistance may be insufficient. The content of the polyalkylene ether glycol segment in the aromatic polyester-based thermoplastic elastomer is calculated based on the chemical shift of the hydrogen atom and its content using nuclear magnetic resonance spectroscopy (NMR), or infrared. It can be calculated by the IR method using a spectrophotometer.

As an aromatic polyester thermoplastic elastomer suitable for the present invention,
(I) a diol component comprising an aliphatic and / or alicyclic diol having 2 to 12 carbon atoms;
(Ii) an aromatic dicarboxylic acid component selected from aromatic dicarboxylic acids and their alkyl esters;
(Iii) Polyalkylene ether glycol as a raw material and those obtained by polycondensation of oligomers obtained by esterification reaction or transesterification reaction may be mentioned.

  As the aliphatic and / or alicyclic diol having 2 to 12 carbon atoms of (i), those generally used as raw materials for polyesters, particularly aromatic polyester-based thermoplastic elastomers, can be used. Specific examples thereof include ethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol and the like. Among these, 1,4-butanediol or ethylene glycol is preferable, and 1,4-butanediol is particularly preferable.

  These diol components may be used individually by 1 type, and may use 2 or more types together.

  As the aromatic dicarboxylic acid (ii), those generally used as raw materials for polyesters, particularly aromatic polyester-based thermoplastic elastomers can be used. Specific examples thereof include terephthalic acid, isophthalic acid, phthalic acid, and 2,6-naphthalenedicarboxylic acid. Among these, terephthalic acid or 2,6-naphthalenedicarboxylic acid is preferable, and terephthalic acid is particularly preferable.

  As the alkyl ester of the aromatic dicarboxylic acid, alkyl esters such as dimethyl ester and diethyl ester of the above aromatic dicarboxylic acid are used. Of these, dimethyl terephthalate and 2,6-dimethyl naphthalene dicarboxylate are preferable.

  These aromatic dicarboxylic acid components may be used individually by 1 type, and may be used in combination of 2 or more type.

  The polyalkylene ether glycol (iii) has a number average molecular weight of usually 400 or more, preferably 500 or more, more preferably 600 or more, and usually 6,000 or less, preferably 4,000 or less, more preferably 3, 000 or less is used. If the number average molecular weight of the polyalkylene ether glycol is too small, sufficient adhesion may not be exhibited. If it is too large, phase separation in the system is likely to occur, and the physical properties of the resulting polymer tend to be reduced. is there. Here, the number average molecular weight refers to that measured by gel permeation chromatography (GPC). For the calibration of GPC, a POLYTETRAHYDROFURAN calibration kit manufactured by POLYMER LABORATORIES, UK may be used.

  Specific examples of the polyalkylene ether glycol include polyethylene glycol, poly (1,2-propylene ether) glycol, poly (1,3-propylene ether) glycol, poly (tetramethylene ether) glycol, poly (hexamethylene ether). ) Glycol and the like.

  These polyalkylene ether glycols may be used alone or in combination of two or more.

  In addition to the above components (i) to (iii), the aromatic polyester-based thermoplastic elastomer is copolymerized with one or more trifunctional or higher alcohols and / or tricarboxylic acids and / or esters thereof in a small amount. Furthermore, aliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid and adipic acid and dialkyl esters thereof may be introduced as a copolymerization component.

As the aromatic polyester-based thermoplastic elastomer of component (a), from the viewpoint of material strength and elongation, the flexural modulus (according to Autograph AG-1000A manufactured by Shimadzu Corporation) is 100 to 1000 MPa, and the density (Toyo Incorporated) Seiki Seisakusho's automatic hydrometer D-H100) is 0.990 to 1.450 g / cm ³ , melting peak temperature by differential scanning calorimeter is 185 to 275 ° C., and JIS-D hardness is 40 to 90. .

  Commercially available products may be used as the aromatic polyester-based thermoplastic elastomer suitable for the present invention, and examples include LG Chem “KEYFLEX” and Mitsubishi Chemical Corporation “Primalloy”.

  As the component (a) aromatic polyester-based thermoplastic elastomer, one type may be used alone, or two or more types may be used in combination.

<Component (b): Aromatic vinyl hydrocarbon-conjugated diene copolymer and / or hydrogenated product thereof>
The aromatic vinyl hydrocarbon-conjugated diene copolymer as the component (b) is not particularly limited, but a styrene elastomer in which the aromatic vinyl hydrocarbon is a styrene compound is particularly preferable. Examples of the styrene elastomer include one or more styrene compounds such as styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, 1,3-butadiene, 2-methyl-1,3- An elastomeric random or block copolymer with one or more conjugated dienes such as butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, etc. Can be mentioned. Component (b) may be a hydrogenated product of these copolymers or a mixture of rubber or the like.

  Specific examples of these styrene elastomers include styrene-butadiene random copolymer, styrene-isoprene random copolymer, styrene-butadiene-styrene triblock copolymer, styrene-isoprene-styrene triblock copolymer, styrene- Styrene-conjugated diene block copolymer such as isoprene-butadiene-styrene copolymer, styrene-isoprene radial block copolymer terminated with polystyrene block, styrene-butadiene multiblock copolymer, styrene-isoprene multiblock copolymer Examples thereof include styrene-butadiene-styrene copolymers and styrene-isoprene-butadiene-styrene copolymers. The component (b) may be a hydrogenated product obtained by hydrogenating these components.

  Examples of the hydrogenated product include styrene-ethylene-butylene-styrene copolymer, which is a hydrogenated product of styrene-butadiene-styrene block copolymer, and styrene, which is a hydrogenated product of styrene-isoprene-styrene block copolymer. An ethylene-propylene-styrene copolymer or a hydrogenated product of a styrene-isoprene-butadiene-styrene block copolymer can be used.

  The styrene content of the styrene elastomer is not particularly limited, but is preferably 5% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 45% by mass or less from the viewpoint of balance between strength and flexibility. More preferably, it is 15 mass% or more and 40 mass% or less. The styrene elastomer may be modified in various ways such as maleic anhydride modification and amine modification. Of these, maleic anhydride modification is preferred.

  The molecular weight of the styrene-based elastomer is preferably 10,000 or more, particularly 50,000 or more, and 1,000,000 or less, particularly 950,000 or less as a polystyrene-reduced weight average molecular weight measured by gel permeation chromatography. If the molecular weight is too small, the mechanical strength tends to be inferior, whereas if it is too large, the moldability tends to be inferior.

  Moreover, when the styrene elastomer is a hydrogenated product of a styrene-conjugated diene copolymer, the hydrogenation rate is preferably 10 to 100%.

  Also, from the viewpoint of material strength and adhesive strength between metals, the tensile strength (according to ASTM D-412) of the styrene elastomer is 1 to 100 MPa, and the JIS-A hardness (according to durometer) is in the range of 20 to 90. Is preferred.

  As the component (b) aromatic vinyl hydrocarbon-conjugated diene copolymer and / or hydrogenated product thereof, one kind may be used alone, or two or more kinds may be used in combination.

<Α, β-ethylenically unsaturated carboxylic acid>
As the α, β-ethylenically unsaturated carboxylic acid and its anhydride used for graft modification of the component (a) and / or the component (b), for example, acrylic acid, maleic acid, fumaric acid, tetrahydrofumaric acid, itaconic acid, Α, β-ethylenically unsaturated carboxylic acids such as citraconic acid, crotonic acid and isocrotonic acid; succinic acid 2-octen-1-yl anhydride, succinic acid 2-dodecen-1-yl anhydride, succinic acid 2-octadecene -1-yl anhydride, maleic anhydride, 2,3-dimethylmaleic anhydride, bromomaleic anhydride, dichloromaleic anhydride, citraconic anhydride, itaconic anhydride, 1-butene-3, 4-dicarboxylic acid anhydride, 1-cyclopentene-1,2-dicarboxylic acid anhydride, 1,2,3,6-tetrahydrophthalic acid anhydride, 3,4,5, -Tetrahydrophthalic anhydride, exo-3,6-epoxy-1,2,3,6-tetrahydrophthalic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, methyl-5-norbornene-2, 3-dicarboxylic anhydride, endo-bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic anhydride, bicyclo [2.2.2] oct-7-ene-2,3 An anhydride of α, β-ethylenically unsaturated carboxylic acid such as 5,6-tetracarboxylic acid anhydride may be mentioned.

  These α, β-ethylenically unsaturated carboxylic acids can be appropriately selected according to the component (a) and / or component (b) to be modified and the modification conditions, and are limited to the case where one kind is used alone. Alternatively, two or more kinds may be used in combination.

  The α, β-ethylenically unsaturated carboxylic acid can be used by dissolving in an organic solvent.

<Radical generator>
Examples of the radical generator used for graft modification of the component (a) and / or the component (b) include t-butyl hydroperoxide, cumene hydroperoxide, and 2,5-dimethylhexane-2,5-di. Hydroperoxide, 2,5-dimethyl-2,5-bis (t-butyloxy) hexane, 3,5,5-trimethylhexanoyl peroxide, t-butylperoxybenzoate, benzoyl peroxide, m-toluoyl Organic and inorganic peroxides such as peroxide, dicumyl peroxide, 1,3-bis (t-butylperoxyisopropyl) benzene, dibutyl peroxide, methyl ethyl ketone peroxide, potassium peroxide, hydrogen peroxide; 2′-azobisisobutyronitrile, 2,2′-azobis (i Butyramide) dihalide, 2,2'-azobis [2-methyl-N-(2-hydroxyethyl) propionamide], azo compounds such as azodi -t- butane; and carbon radical generators such as dicumyl like.

  The radical generator is appropriately selected according to the type of component (a) and / or (b) to be subjected to the modification reaction, the type of α, β-ethylenically unsaturated carboxylic acid as the modifier, and the modification conditions. 1 type may be used independently and 2 or more types may be used together.

  The radical generator can be used after being dissolved in an organic solvent.

<Graft modification reaction>
As the modification reaction for obtaining the graft-modified elastomer component in the present invention, various known reaction methods such as a melt-kneading reaction method, a solution reaction method, and a suspension-dispersion reaction method can be used. The method is preferred.

  In the case of the melt-kneading reaction method, the components described above may be melt-kneaded after being uniformly mixed at a predetermined blending ratio. For mixing, a Henschel mixer, a ribbon blender, a V-type blender, or the like is used. For melt kneading, a Banbury mixer, a kneader, a roll, a multi-screw kneading extruder such as a single screw or a twin screw, or the like is used.

  In the melt-kneading, the component (a) and / or the component (b) is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 150 ° C. or higher, and usually 300 ° C. or lower, preferably 280 ° C. Hereinafter, it is more preferably performed at a temperature of 270 ° C. or lower.

  The amount of the α, β-ethylenically unsaturated carboxylic acid used as the modifier is usually 0.01 parts by mass or more, preferably 0 with respect to 100 parts by mass of the component (a) and / or the component (b) to be used for modification. 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, usually 30 parts by mass or less, preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and most preferably 1 part by mass or less. If the amount of α, β-ethylenically unsaturated carboxylic acid used is too small, sufficient modification cannot be performed, and if too large, a modification rate corresponding to the amount used cannot be obtained, which is uneconomical.

  The amount of the radical generator used is usually 0.001 part by mass or more, preferably 0.005 part by mass or more, more preferably 100 parts by mass of the component (a) and / or the component (b) to be used for modification. 0.01 parts by mass or more, usually 3 parts by mass or less, preferably 0.5 parts by mass or less, more preferably 0.3 parts by mass or less, and particularly preferably 0.2 parts by mass or less. When the amount of the radical generator used is too small, the modification does not occur sufficiently. When the amount is too large, the molecular weight (decrease in viscosity) during modification is large, and the material strength is remarkably lowered. That is, in this modification reaction, a graft polymerization (graft modification) reaction in which α, β-ethylenically unsaturated carboxylic acid is added to component (a) and / or (b) mainly occurs, but a decomposition reaction also occurs. As a result of decomposition, the resulting modified product has a reduced molecular weight and a lower melt viscosity. If the amount of the radical generator used is too large, a graft polymerization reaction is likely to occur, but at the same time, a decomposition reaction that leads to a decrease in melt viscosity is likely to occur.

The graft modification reaction may be performed only on component (a) by adding α, β-ethylenically unsaturated carboxylic acid and a radical generator to component (a), and α, β-ethylene on component (b). Alternatively, the unsaturated unsaturated carboxylic acid and the radical generator may be added to the component (b). Further, the graft modification reaction is performed on the components (a) and (b) by adding an α, β-ethylenically unsaturated carboxylic acid and a radical generator to a mixture of the components (a) and (b). May be.
That is, the graft-modified elastomer component in the present invention may be a mixture of the graft-modified component (a) and the graft-modified component (b), or may be graft-modified with the unmodified component (a) (b). And a mixture of the component (a) graft-modified and the component (b) unmodified. Moreover, what mixed (a) component and / or (b) component further to these mixtures may be used.

<Reaction product>
As described above, in the modification treatment of the component (a) and / or the component (b) with the α, β-ethylenically unsaturated carboxylic acid in the presence of the radical generator, the component (a) and / or the component (b) In addition to the graft polymerization reaction to which α, β-ethylenically unsaturated carboxylic acid is added, a transesterification reaction or the like may occur as a decomposition reaction or other reaction. For this reason, the reaction product obtained is generally a thermoplastic resin composition containing unreacted raw materials and reaction by-products together with the graft modified product. The content of the graft modified product in the reaction product is usually 10% by mass or more, preferably 30% by mass or more, but the reaction product may be a graft modified product alone.

  The reaction product obtained by adding the α, β-ethylenically unsaturated carboxylic acid and the radical generator to the mixture of the component (a) and the component (b) and performing the graft modification reaction is the composite molded article of the present invention. The thermoplastic resin composition can be used for molding as it is.

  The modification rate (graft amount) in the thermoplastic resin composition for composite molded articles of the present invention is the α, β-ethylenic property introduced by graft modification with respect to 100% by mass in total of the components (a) and (b). The proportion of saturated carboxylic acid, the lower limit is usually 0.01% by mass, preferably 0.015% by mass, more preferably 0.02% by mass, and the upper limit is usually 10% by mass, preferably 7% by mass, more preferably 5% by mass. When the amount of grafting is too small, improvement in adhesion to metal cannot be expected because the functional group is too small, and when it is too large, the material strength decreases due to molecular degradation in the process of modification.

  Here, the graft amount is a ratio of the α, β-ethylenically unsaturated carboxylic acid graft-polymerized to the component (a) and / or the component (b) to the total 100% by mass of the component (a) and the component (b). However, the graft amount is measured by the method described in the Examples section below.

<Physical properties of graft-modified elastomer component>
The JIS-D hardness (the hardness according to durometer type D according to JIS-K6253) of the graft-modified elastomer component contained in the thermoplastic resin composition for composite molded articles of the present invention is usually 10 or more, preferably 15 or more, more preferably 20 or more, usually 100 or less, preferably 95 or less, more preferably 90 or less. When the JIS-D hardness is too low, the mechanical strength of the molded product obtained using the thermoplastic resin composition for composite molded products containing this graft-modified elastomer component tends to be inferior. Impact may be inferior.

[Other ingredients]
The thermoplastic resin composition for a composite molded article of the present invention that constitutes the contact portion between the thermoplastic resin portion and the metal includes a resin component other than the above graft-modified elastomer component and rubber within the scope of the present invention. Other components such as components or fillers and various additives may be contained. For example, you may mix | blend other polyolefin-type elastomers other than (a) component and (b) component. Moreover, you may mix | blend softeners, such as rubber components, such as natural rubber and synthetic rubber (for example, polyisoprene rubber), and process oil. The softening agent is added for the purpose of promoting plasticization of the rubber component and improving the fluidity of the resulting composition. These may be paraffinic, naphthenic, or aromatic.

  As filler, calcium carbonate, talc, silica, kaolin, clay, diatomaceous earth, calcium silicate, mica, asbestos, alumina, barium sulfate, aluminum sulfate, calcium sulfate, magnesium carbonate, carbon fiber, glass fiber, glass bulb, molybdenum sulfide, Examples thereof include graphite and shirasu balloons.

  Examples of the additive include a heat resistance stabilizer, a weather resistance stabilizer, a colorant, an antistatic agent, a flame retardant, a nucleating agent, a lubricant, a slip agent, and an antiblocking agent. Known heat-resistant stabilizers such as phenol-based, phosphorus-based, and sulfur-based stabilizers can be used. Further, as the weather resistance stabilizer, known ones such as hindered amines and triazoles can be used. Examples of the colorant include carbon black, titanium white, zinc white, red pepper, azo compound, nitroso compound, and phthalocyanine compound. Any known antistatic agent, flame retardant, nucleating agent, lubricant, slip agent, antiblocking agent, hydrolysis inhibitor, etc. can be used.

  When the thermoplastic resin composition for a composite molded article of the present invention contains other components other than the graft-modified elastomer component, the above-mentioned graft-modified elastomer component is sufficient for obtaining the effect of adhesion to metal to the composite molded product. The content of other components in the thermoplastic resin composition is preferably 20% by mass or less.

[Metal base material]
Next, the metal base material which comprises the metal part of the composite molded product of this invention is demonstrated.

  In the present invention, as the metal substrate constituting the metal part, at least one metal selected from metals such as chromium, zinc, magnesium, aluminum, tin, copper, iron, nickel, or an alloy of two or more thereof Specifically, various steel plates (sheets) such as hot rolled steel plate, cold rolled steel plate, tin plate, chin-free steel plate, stainless steel plate, aluminum steel plate, or galvanized steel plate, Examples include various plated steel sheets (sheets) such as nickel-plated steel sheets.

  More specifically, as the metal substrate, steel plate (cold rolled mild steel plate / bright finish / SPCC-S8), pure aluminum plate (A1050P), corrosion-resistant aluminum plate (for beer / juice cans, A5052P), stainless steel plate (Fe / Cr / Ni alloy, SUS304), pure copper plate (C1100P), tin plate (galvanized steel plate, SGCC), tin plate (tin-plated steel plate / 0.5 mm thickness, SPTE), chrome plated plate (SPCC-S8) Chrome plating), nickel plating plate (SPCC-S8 nickel plating), and the like.

  In the present invention, the metal base is usually subjected to degreasing and cleaning treatment on the surface and then composited with a thermoplastic resin. Even if the surface is further treated with a silane coupling agent, Good. The silane coupling agent applied to the silane coupling treatment is not particularly limited, and a normal silane coupling agent can be used. For example, vinyl tris (β-methoxyethoxy) silane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ- Glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ -Aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane and the like.

  In the present invention, as the silane coupling agent, a partial condensate of the above-described silane coupling agent and alkylalkoxysilane, or γ-methacryloxypropyltrimethoxysilane which is a polymerizable silane coupling agent and other ( A polymer with a (meth) acrylate monomer can also be used.

  The silane coupling treatment is performed by applying one or more of the various silane coupling agents described above as a solution such as an organic solvent or a water mixed solvent, and applying and drying the solution on various metal substrates.

  The shape of the metal substrate according to the present invention is not particularly limited, and may be a plate shape (including a sheet shape), a cube, a rectangular parallelepiped, a container shape, or other irregular shapes such as a curved shape.

[Composite molded product]
The composite molded article of the present invention in which the metal and the thermoplastic resin part are integrated is obtained by bringing the thermoplastic resin composition for a composite molded article usually provided in the thermoplastic resin part into contact with the above-mentioned metal substrate in a hot melt state. In this way, it is manufactured efficiently and economically.

  For the production of the composite molded article of the present invention, a general synthetic resin molding method, more specifically, a T-die laminate molding method, an insert injection molding method, a core back injection molding method, a sandwich injection molding method, an injection press A synthetic resin molding method such as a molding method can be employed.

At the time of heat-sealing, a thermoplastic resin composition for composite molded products may be formed in advance into a sheet shape, etc., and a method of laminating a molded sheet on a metal substrate and hot pressing may be employed. In this case, heat fusion to a metal substrate may be performed. For example, a molding raw material containing the above-described thermoplastic resin composition for a composite molded article is melt-extruded from an extruder and is preheated (for example, heated to 160 ° C.) and pressed against a traveling metal sheet to form a heat-sealing coating layer. A method is mentioned.
In addition, a metal base material molded into a desired shape is mounted in a mold, and a molding raw material composed of the above-described thermoplastic resin composition for composite molded products is melt-injected into a composite by a screw type injection molding machine. A method of forming an injection-molded body can also be adopted.

  The temperature at which the thermoplastic resin composition part for composite molded article and the metal substrate are heat-sealed varies depending on the time and pressure of heat-sealing, but the melting point of the graft-modified elastomer component is -10 ° C or higher. It is preferable that the temperature is higher than the melting point of the graft-modified elastomer component, more preferably higher than the melting point of the graft-modified elastomer component. Preferably there is. That is, the thermal fusion temperature is higher than the melting point of the graft-modified elastomer component, and the graft-modified elastomer component melts at the time of thermal fusion, and the behavior of the functional group of the graft-modified elastomer component becomes active. Bonds firmly at the interface. However, if the heat-sealing temperature is excessively high, the graft-modified elastomer component tends to deteriorate, so the melting point of the graft-modified elastomer component + 100 ° C. or less (100 ° C. or more higher than the melting point of the graft-modified elastomer component). preferable. The higher the heat fusion pressure, the better, but it is usually about 0.05 to 50 MPa from the viewpoint of production efficiency and the performance of the machine used. The longer the heat fusion time, the better. However, from the viewpoint of production efficiency, it is usually about 1 second to 5 minutes.

  When the composite molded product of the present invention is formed by forming a coating layer composed of a thermoplastic resin composition molded part for a composite molded product on a metal substrate of various shapes such as a plate shape, the heat for the composite molded product The thickness of the coating layer formed of the molded part of the plastic resin composition is preferably 1 μm or more, particularly about 5 to 2000 μm in terms of its protective effect and the like.

  However, the composite molded product of the present invention is not limited to a metal substrate, and is not limited to the one in which a coating layer made of the thermoplastic resin composition for composite molded products is formed, and the thermoplastic resin composition for composite molded products. As long as the molded part and the metal part are integrated, there is no limitation on the shape and overall shape of each part. Therefore, the thermoplastic resin composition part for composite molded products having a shape other than the layer shape may be integrated with the metal base material having a shape other than the plate shape. In addition, a coating layer is formed on the surface of the thermoplastic resin composition part for composite molded products (surface opposite to the metal substrate) to improve the appearance, design and physical properties of the surface. In this case, the thermoplastic resin composition for a composite molded article of the present invention has an advantage of excellent adhesion to the coating layer.

  In this case, examples of paints used for painting include paints that are widely used, such as acrylic paints, epoxy paints, polyester paints, urethane paints, alkyd paints, and melamine paints. Among these, acrylic paints, polyester paints, urethane paints, particularly urethane paints are preferable because they have high affinity with the functional groups of the graft-modified elastomer component and better adhesion. These paints may be either a two-component type or a one-component type.

  As a method of applying such a paint to the thermoplastic resin composition molded part for a composite molded article, a generally used method can be adopted. For example, a method of applying using a spray gun, a method of applying a brush, a roll There is a method using a coater or the like.

  The thickness of the coating film can be changed according to the purpose of use of the composite molded product and is not particularly limited, but is usually in the range of 1 to 500 μm after drying.

  In addition, you may apply | coat a coating material further on the coating film formed with the said coating material. Examples of the top coat include acrylic paint, fluorine paint, silicon paint, alkyd paint, and the like.

  In coating, the thermoplastic resin composition for composite molded articles of the present invention has excellent adhesion to paints, and thus excellent coating film adhesion without pretreatment such as primer treatment or corona discharge treatment. Can be obtained. Therefore, when performing painting, these pretreatments can be omitted to reduce the painting process and improve the working environment.However, in the present invention, pretreatment such as primer treatment and corona discharge treatment is not excluded. However, by performing these pretreatments, it is possible to obtain even better coating film adhesion.

  In addition, a thermoplastic resin layer other than the thermoplastic resin composition for composite molded products may be laminated on the surface of the thermoplastic resin composition molded portion for composite molded products opposite to the metal substrate. The thermoplastic resin composition for composite molded articles of the present invention has a good adhesion to not only metals but also thermoplastic resins, and a laminated composite molded article excellent in integrity can be obtained. In this case, as the thermoplastic resin to be laminated, polyethylene, polypropylene, ethylene / vinyl acetate copolymer, polyamide, polybutylene terephthalate, polyethylene terephthalate, polyphenylene sulfide, polyphenylene ether, polycarbonate, the above-mentioned aromatic polyester before graft modification 1 type or 2 types or more of thermoplastic resins such as thermoplastic elastomers, aromatic vinyl hydrocarbon-conjugated diene copolymers, etc., and a laminate of a thermoplastic resin composition for a composite molded article and a thermoplastic resin is It can be formed by integral molding by two-layer molding or the like, and by joining separately molded ones by adhesion or fusion.

  In the case of such a laminated structure, the thermoplastic resin composition for composite molded articles of the present invention interposed between the metal substrate and the laminated portion of the thermoplastic resin for the same reason as the above-described coating layer. The thickness of the molded part is preferably 5 μm or more.

[Use]
The thermoplastic resin composition for composite molded articles according to the present invention has functionality such as surface protection action, buffer action, sound absorption action, vibration absorption action, decoration action, etc. on various metal members because of its excellent adhesion to metal. A coating layer can be formed to improve functionality in various applications. Further, by utilizing the excellent adhesiveness to both the metal and the thermoplastic resin of the thermoplastic resin composition for composite molded article of the present invention, the adhesive between the metal and the metal, the adhesive between the metal and the thermoplastic resin Therefore, the composite molded article of the present invention is a metal / thermoplastic resin composition for composite molded article / metal, or a metal / thermoplastic resin composition for composite molded article / other thermoplastic resins. It can also be set as the composite molded article which has the laminated structure of.

  Thus, the composite molded article of the present invention formed by integrating a metal and a thermoplastic resin can be configured according to various purposes. Hereinafter, although the application example of the composite molded article of this invention is demonstrated according to a use, it cannot be overemphasized that the application example is not limited to the following description.

(1) Composite molded products in the field of portable electronic devices made of various magnesium alloys.
For example, thin laptop computers have recently been manufactured by light-weight magnesium alloy injection molding by the thixomolding method using an injection molding machine or by die-casting to meet the need for light weight. Yes. The composite molded product of the present invention can be applied to the above-described casings and lightweight portable electronic devices.

  (2) In order to absorb vibration generated from a motor or the like, the composite molded product of the present invention having excellent vibration absorption can be applied as a metal fixing plate applied to a motor or the like.

  (3) As various metal protectors (protective covers), the composite molded article of the present invention can be applied to provide at least a part of the surface, for example, a coat part, with elastic deformation ability and shock absorption ability. .

  (4) The exterior body (consisting of a main body and a lid) of various devices with large heat radiation, such as a transceiver with high power consumption, is made of metal instead of plastic, but the surface is waterproof. The composite molded article of the present invention can be applied to this type of exterior body in order to provide performance or to mute the sound caused by contact between the main body and the lid.

  (5) In order to mute the sound (noise) caused by the contact between metals in the joint portion or the like, the composite molded product excellent in the silencing effect of the present invention can be applied. In addition, in this kind of application, waterproofness, water-proofing property, etc. are improved at the same time.

  (6) The composite molded product of the present invention can be applied in order to give a gripping part such as a metal paper knife, spoon or fork to a soft feeling or a high-class feeling.

  (7) The composite molded product of the present invention can be applied to cans such as beverage cans and food cans. That is, the thermoplastic resin composition layer for composite molded articles can be formed as a surface protective layer inside or outside these cans.

  (8) When a metal and a thermoplastic resin or a metal and a metal are bonded to produce an integrated product thereof, the integrated structure of the composite molded product of the present invention can be employed.

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 as long as the gist thereof is not exceeded.
In the following, the raw materials used and various measuring methods are as follows.

[Raw materials]
(1) Aromatic polyester thermoplastic elastomer: The hard segment is polybutylene terephthalate, the soft segment is poly (tetramethylene ether) glycol having a number average molecular weight of 900, and the content of poly (tetramethylene ether) glycol is 32% by mass Aromatic polyester polyether block copolymer (flexural modulus: 196 MPa, density: 1.2 g / cm ³ , melting peak temperature by differential scanning calorimeter: 214 ° C., JIS-D hardness: 54)

(2) Hydrogenated aromatic vinyl hydrocarbon-conjugated diene copolymer: styrene-ethylene-butylene-styrene copolymer having a polystyrene content of 33% by mass (weight average molecular weight: 240,000, tensile strength: 20 MPa, JIS-A hardness: 60)

(3) α, β-ethylenically unsaturated carboxylic acid component: “Maleic anhydride reagent special grade” manufactured by Wako Pure Chemical Industries, Ltd.

(4) Radical generator: m-toluoyl peroxide / benzoyl peroxide mixture (“Nyper BMT-K40” manufactured by NOF Corporation)

(5) Antioxidant: “SONGNOX1010” manufactured by SONGWON

[Measuring method]
(1) Graft amount of maleic anhydride A test piece was prepared by a compression molding method, and the amount of maleic anhydride graft was quantified by an IR method using an infrared spectrophotometer.

(2) JIS-D hardness It measured by durometer type D according to JIS-K6253.

(3) MFR
According to JIS-K7210-1, the temperature was 230 ° C. and the load was 2.16 kg.

(4) Adhesiveness A strip-shaped cut having a width of 10 mm and a length of 100 mm is made in the thermoplastic resin composition layer of the composite molded product, and the thermoplastic resin composition layer is pulled 90 ° with respect to the metal plate at a tensile speed of 50 mm. A tensile test was performed at a rate of 1 minute, and the peel strength at the fusion interface between the thermoplastic resin composition layer and the metal plate was measured. As a preparation for measuring the peel strength, pre-peeling was performed, and when securing the fixing allowance, the case where pre-peeling could not be performed was regarded as impossible.

[Example 1]
(A) component: 85 parts by mass of aromatic polyester-based thermoplastic elastomer, (b) component: α, β-ethylenically unsaturated with respect to 15 parts by mass of hydrogenated aromatic vinyl hydrocarbon-conjugated diene copolymer Carboxylic acid component 0.5 part by mass, radical generator 0.13 part by mass, antioxidant 0.1 part by mass are mixed, and this is made by JSW Corporation “TEX25α3 type kneader” (diameter 25 mm, temperature 180-230). And then kneaded in a pelletizer through a pelletizer to produce a thermoplastic resin composition. The graft amount of this thermoplastic resin composition was 0.05% by mass. Moreover, the JIS-D hardness of the obtained thermoplastic resin composition was 45, and MFR (230 degreeC, 2.16 kg load) was 19.6 g / 10min.

  The obtained pellets of the thermoplastic resin composition were press-molded by the following procedure to form a 70 mm × 150 mm × 0.5 mm sheet, and the obtained sheet and a hot-dip galvanized steel sheet (SGCC 70 mm × 150 mm × 1 .0 mm) and press bonding was performed according to the following procedure.

[Press molding procedure]
(1) Place 75 g of pellets on a 230 mm × 230 mm × 0.5 mm spacer (mold).
(2) Insert the above (1) between press molding machines heated to 240 ° C. and close the molding machine.
(3) Keep warm at 240 ° C for 5 minutes without applying pressure.
(4) Then, apply a pressure of 10 MPa and hold for 3 minutes.
(5) Release the pressure, replace with a cooling press (10-30 ° C., water temperature), apply a pressure of 10 MPa, cool for 2 minutes or more, take out, and adjust to a predetermined shape.

[Press bonding procedure]
(1) Place a resin sheet previously formed on a hot dip galvanized steel sheet in a 1.2 mm thick spacer.
(2) The above (1) is inserted between press molding machines heated to a predetermined press bonding temperature (upper 250 ° C., lower 260 ° C.) and the molding machine is closed.
(3) After holding for 5 minutes without applying pressure, a pressure of 1 MPa is applied for 3 minutes.
(4) Then, take out, replace with a cooling press, apply pressure of 1 MPa, cool for 2 minutes or more, and take out.

  The composite molded product thus obtained was evaluated for adhesion, and the results are shown in Table 1.

[Comparative Example 1]
A thermoplastic resin composition was produced in the same manner as in Example 1 except that 100 parts by mass of the aromatic polyester-based thermoplastic elastomer was used and the hydrogenated aromatic vinyl hydrocarbon-conjugated diene copolymer was not used. Similarly, adhesion was evaluated and the results are shown in Table 1. At this time, the graft amount of the obtained thermoplastic resin composition was 0.05 mass%. Moreover, the JIS-D hardness of the obtained thermoplastic resin composition was 50, and MFR (230 degreeC, 2.16Kg load) was 39.6 g / 10min.

  As is clear from the results of Example 1 and Comparative Example 1 above, the metal by the carboxyl group (—COOH) introduced by graft modification by further blending the component (b) with the component (a) and performing graft modification. With the excellent affinity with and the effect of improving the adhesion to the metal by the component (b), the adhesion to metal is remarkably improved, and a result of being incapable of peeling is obtained in the peeling test.

Claims (8)

A thermoplastic resin composition for molding at least a contact portion of the thermoplastic resin portion of a composite molded product obtained by integrating a metal and a thermoplastic resin portion with the metal, comprising the following component (a): It contains at least the following component (b), and one or both of the component (a) and the component (b) are graft-modified with an α, β-ethylenically unsaturated carboxylic acid. A thermoplastic resin composition for composite molded articles.
(A) Component: Aromatic polyester-based thermoplastic elastomer (b) Component: Aromatic vinyl hydrocarbon-conjugated diene copolymer and / or hydrogenated product thereof   2. The composite molding according to claim 1, wherein the component (a) is contained in an amount of 50 to 90% by mass and the component (b) is contained in an amount of 10 to 50% by mass in a total of 100% by mass of the component (a) and the component (b). Product thermoplastic resin composition.   The thermoplastic resin composition for composite molded articles according to claim 1 or 2, wherein the aromatic polyester-based thermoplastic elastomer contains a polyalkylene ether glycol segment.   The thermoplastic resin composition for composite molded articles according to claim 3, wherein the content of the polyalkylene ether glycol segment in the aromatic polyester-based thermoplastic elastomer is 1 to 80% by mass.   The aromatic vinyl hydrocarbon-conjugated diene copolymer is a styrene-butadiene-styrene copolymer and / or a styrene-isoprene-butadiene-styrene copolymer. 2. A thermoplastic resin composition for composite molded articles.   The graft amount of the α, β-ethylenically unsaturated carboxylic acid is 0.01 to 10% by mass with respect to 100% by mass in total of the component (a) and the component (b). Item 2. A thermoplastic resin composition for composite molded articles.   A composite molded article using the thermoplastic resin composition for a composite molded article according to any one of claims 1 to 6.   The composite molded article according to claim 7, comprising a metal layer and an adhesive layer, wherein the adhesive layer contains the thermoplastic resin composition for a composite molded article.