CN109715393B

CN109715393B - Joint body of thermoplastic resin composition and metal and manufacturing method thereof

Info

Publication number: CN109715393B
Application number: CN201880003557.7A
Authority: CN
Inventors: 左璞晶; 宋婷婷; 陈斌; 加藤公哉; 大久保拓郎
Original assignee: Toray Advanced Materials Research Laboratories China Co Ltd
Current assignee: Toray Advanced Materials Research Laboratories China Co Ltd
Priority date: 2017-07-28
Filing date: 2018-07-26
Publication date: 2020-11-03
Anticipated expiration: 2038-07-26
Also published as: WO2019020065A1; CN109715393A

Abstract

The present invention provides a joined body of a thermoplastic resin composition and a metal having excellent joining performance, and a method for producing the same. The thermoplastic resin composition contains a terminal modified polyamide resin, wherein the content of the terminal modified polyamide resin in the thermoplastic resin composition is 5-100 wt% of the total weight of the thermoplastic resin composition, the terminal modified polyamide resin has a terminal structure represented by the formula I, -X- (R)₁‑O)n‑R₂Formula I in the formula I, n is an integer of 2-100, R₁The same or different, are alkylene groups having 2 to 10 carbon atoms, R₂An alkyl group having 1 to 30 carbon atoms, -X-is-NH-, -O-, -C (═ O) -, -NH-C (═ O) -O-, -NH-C (═ O) -NH-or-CH (OH) -CH₂-any of; the content of the structure shown in the formula I in the terminal modified polyamide resin is 0.05-20 wt% of the total weight of the terminal modified polyamide resin.

Description

Joint body of thermoplastic resin composition and metal and manufacturing method thereof

Technical Field

The invention belongs to the field of a composite of a polymer and a metal, and particularly discloses a conjugant of a thermoplastic resin composition and the metal and a manufacturing method thereof.

Background

With the increasingly prominent three problems of energy, safety and environmental protection, the light weight of the automobile is more and more emphasized. Since the specific gravity is much smaller than that of metal, the application of engineering plastics to automobiles is gradually increasing, but in some structural parts, the mechanical strength of the engineering plastics itself is still difficult to meet the requirement. The metal/plastic hybrid composite material has the characteristics of high metal strength and light plastic weight, and meets the requirements on mechanical strength and light weight of automobile structural parts.

At present, the metal components and the plastics are mainly jointed together by mechanical riveting and adhesive bonding to form the hybrid composite material, but in the jointing modes, the plastic parts and the metal parts are respectively processed and then jointed together by riveting, adhesive bonding and the like to form a complete part. The above bonding method has the problems of complex process, easy deterioration of adhesive, and the like.

In recent years, a method of bonding a resin directly to a metal by injection molding has been studied more and more. International patent application publication WO2012/132639 discloses a composite of a thermoplastic resin containing an inorganic filler capable of raising the crystallization temperature of the resin and a metal, but the composite obtained by this method is still insufficient in the bondability between the resin and the metal. International patent application laid-open publication WO2015/022955 discloses a composite of a thermoplastic resin and a metal, wherein the thermoplastic resin may be a polyamide elastomer modified by copolymerization of polyether or a thermoplastic resin composition comprising a water-absorbent thermoplastic resin and a metal hydroxide. However, the mechanical properties of polyamide elastomers are significantly reduced compared to polyamide homopolymers. On the other hand, compared with polyamide homopolymer, the glass transition temperature of polyamide elastomer is lower, the curing speed is lower during injection molding, and the molding period is longer. Meanwhile, the polyamide elastomer is not well bonded to the metal.

Chinese patent application publication CN105479659A discloses a composite of a plastic material and a metal material containing polyether block amide, which has excellent bonding force between the plastic material and the metal and provides a certain degree of sealing property, but has a decreased mechanical property compared to polyamide homopolymer due to a higher polyether structure content in the polyether block amide, and has insufficient bonding property between the polyether block amide and the metal.

Documents of the prior art

Patent document 1: international patent application publication WO2012/132639

Patent document 2: international patent application laid-open publication WO2015/022955

Patent document 3: chinese patent application laid-open gazette CN105479659A

Disclosure of Invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide a joined body of a thermoplastic resin composition containing a polyamide resin having polyether chains introduced into the ends thereof, and a metal, wherein the joining strength between the thermoplastic resin composition and the metal is improved, and the thermoplastic resin composition itself maintains high mechanical properties.

The invention also provides a method for manufacturing the joint body of the thermoplastic resin composition and the metal, and the method can efficiently prepare the joint body of the metal and the resin and lay a foundation for continuous production.

The invention is composed of the following contents:

1. a joint body of a thermoplastic resin composition and a metal, the thermoplastic resin composition containing a terminal-modified polyamide resin, the terminal-modified polyamide resin being contained in an amount of 5 to 100 wt% based on the total weight of the thermoplastic resin composition, the terminal-modified polyamide resin having a terminal structure represented by formula I,

-X-(R₁-O)n-R₂formula I

In the formula I, n is an integer of 2-100, R₁The same or different, are alkylene groups having 2 to 10 carbon atoms, R₂An alkyl group having 1 to 30 carbon atoms, -X-is-NH-, -O-, -C (═ O) -, -NH-C (═ O) -O-, -NH-C (═ O) -NH-or-CH (OH) -CH₂-any of; the content of the structure shown in the formula I in the terminal modified polyamide resin is 0.05-20 wt% of the total weight of the terminal modified polyamide resin.

2. The junction body according to 1, wherein n is an integer of 16 to 50 in the terminal structure represented by the formula I.

3. The junction body according to 1, wherein n is an integer of 16 to 25 in the terminal structure represented by the formula I.

4. The adapter according to 1, wherein R is in the terminal structure represented by formula I₁The same or different alkylene groups having 2 to 4 carbon atoms.

5. The adapter according to 1, wherein R is in the terminal structure represented by formula I₂Is an alkyl group having 1 to 20 carbon atoms.

6. The adapter according to 1, wherein R is in the terminal structure represented by formula I₂Is methyl.

7. The adapter according to 1, wherein-X-in the terminal structure represented by the formula I is-NH-.

8. The joined body described in the above item 1, wherein the content of the terminal structure represented by the above formula I in the terminal-modified polyamide resin is 0.1 to 15 wt% based on the total weight of the terminal-modified polyamide resin.

9. The joined body described in the above item 1, wherein the content of the terminal structure represented by the above formula I in the terminal-modified polyamide resin is 0.1 to 10 wt% based on the total weight of the terminal-modified polyamide resin.

10. The bonded body described in the above item 1, wherein the thermoplastic resin composition has a tensile shear strength of not less than 10MPa as measured at a tensile speed of 5mm/min according to a bonded body test specimen specified in ISO 19095.

11. The joined body according to the above 1, which is obtained by directly joining a thermoplastic resin composition and a metal.

12. The junction body described in the above 1, wherein the terminal-modified polyamide resin having a terminal structure represented by the formula I is a polyamide resin solution prepared in an amount of 0.01g/ml using 96 wt% sulfuric acid as a solvent, and has a relative viscosity η r of 1.1 to 5.0 as measured at 25 ℃.

13. The joint body according to the above 1, wherein the weight average molecular weight Mw of the terminal-modified polyamide resin having a terminal structure represented by the formula I is in the range of 10,000 to 400,000 as measured by gel permeation chromatography.

14. The joined body described in the above 1, wherein the melting point of the terminal-modified polyamide resin having a terminal structure represented by the formula I is 215 ℃ or higher.

15. The joint body according to the above 1, the thermoplastic resin composition further comprising an inorganic filler, the content of the inorganic filler being 5 to 80 wt% of the total weight of the thermoplastic resin composition.

16. A method for producing a joined body described in any one of 1 to 15 above, wherein the joined body is formed by injection molding of a thermoplastic resin composition and a metal previously placed in a mold after heating and melting.

17. The production method according to 16, wherein the temperature of the mold of the joined body is 60 to 180 ℃ in the injection molding process.

18. A method for manufacturing the joined body according to any one of 1 to 15, characterized in that: the joined body is obtained by welding a molded article of the thermoplastic resin composition and a metal by laser irradiation.

The joined body of the thermoplastic resin composition of the present invention and a metal can be used for automobile parts, electronic and electric product parts, structural materials, and the like.

The above-described invention will be described in detail below:

the thermoplastic resin composition used in the joined body of the invention comprises a terminal-modified polyamide resin having a terminal structure represented by the formula I, the content of the terminal-modified polyamide resin being 5 to 100 wt% based on the total weight of the thermoplastic resin composition,

-X-(R₁-O)n-R₂formula I

In the formula I, n is an integer of 2-100, R₁The same or different, and the number of carbon atoms is 2 to 10 alkylene group, R₂An alkyl group having 1 to 30 carbon atoms, -X-is-NH-, -O-, -C (═ O) -, -NH-C (═ O) -O-, -NH-C (═ O) -NH-or-CH (OH) -CH₂-any of; the content of the structure shown in the formula I in the terminal modified polyamide resin is 0.05-20 wt% of the total weight of the terminal modified polyamide resin.

In the present invention, when the thermoplastic resin composition contains only a single component of the terminal-modified polyamide resin, it is also defined as a thermoplastic resin composition.

The main chain structure of the terminal-modified polyamide resin used in the present invention is not particularly limited. The monomer material constituting the main chain structure of the terminal-modified polyamide resin may be a diacid, a diamine, an amino acid, a lactam or the like, and specific examples thereof include, but are not limited to, the following: amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid or 4-aminomethylbenzoic acid; lactams such as caprolactam, omega-undecalamide or omega-dodecalactam; aliphatic diamines such as ethylenediamine, propylenediamine, butylenediamine, pentylenediamine, hexylenediamine, heptylenediamine, octylenediamine, nonylenediamine, decylenediamine, undecylenediamine, dodecylenediamine, tridecylenediamine, tetradecylenediamine, pentadecylenediamine, hexadecylenediamine, heptadecylenediamine, octadecylenediamine, nonadecylenediamine, eicosylenediamine, 2-methyl-1, 5-pentylenediamine, and 2-methyl-1, 8-octylenediamine; alicyclic diamines such as cyclohexanediamine, 4 '-diaminodicyclohexylmethane, and 4, 4' -methylenebis (2-methylcyclohexylamine); aromatic diamines such as xylylenediamine; aliphatic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2-chloro-1, 4-phthalic acid, 2-methyl-1, 4-phthalic acid, 5-methylisophthalic acid, and 5-sodium sulfoisophthalic acid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. Alkyl diesters and dicarboxylic acid dichlorides derived from dicarboxylic acids can also be exemplified as the monomer raw materials constituting the main chain structure of the polyamide resin. The main chain of the terminal-modified polyamide resin used in the present invention may specifically be a homopolymeric structure prepared from the above-mentioned monomer or a copolymeric structure prepared from the above-mentioned monomer.

Examples of the polyamide main chain structure of the terminal-modified polyamide resin include, but are not limited to, the following: polycaprolactam (nylon 6), polyundecanolactam (nylon 11), polydodecanolactam (nylon 12), polyhexamethylene adipamide (nylon 66), polytetramethyleneadipamide (nylon 46), polypentylglycol adipamide (nylon 56), polytetramethyleneadipamide (nylon 410), polypentylglycol sebacamide (nylon 510), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecanoamide (nylon 612), polydecamethylenesebacamide (nylon 1010), polydecamethylenedodecamide (nylon 1012), polycaprolactam/polyhexamethylene adipamide copolymer (nylon 6/66), polymetaxylxylylene adipamide (MXD6), polymetaxylxylylene sebacamide (MXD10), polyparaxylylenesebacamide (PXD10), polyparaxylylene-nanediamide (nylon 9T), polyparaxylylene-xylylene-terephthalamide (nylon 10T), polyparaxylylene-undecamide (nylon 11T), Poly (p-dodecylene terephthalamide) (Nylon 12T), poly (p-pentylene terephthalamide)/poly (hexamethylene terephthalamide) copolymer (Nylon 5T/6T), poly (2-methylpentylene terephthalamide)/poly (hexamethylene terephthalamide) copolymer (Nylon M5T/6T), poly (hexamethylene adipamide)/poly (hexamethylene terephthalamide) copolymer (Nylon 66/6T), poly (hexamethylene adipamide)/poly (hexamethylene isophthalamide) copolymer (Nylon 66/6I), poly (hexamethylene adipamide)/poly (hexamethylene terephthalamide)/poly (hexamethylene isophthalamide) copolymer (Nylon 66/6T/6I), poly (4, 4 '-methylenebis (2-methylcyclohexylamine) (Nylon MACMT), poly (4, 4' -methylenebis (2-methylcyclohexylamine) (Nylon MI), Polydodecamide 4, 4 '-methylenebis (2-methylcyclohexylamine) (nylon MACM12), poly (terephthaloyl 4, 4' -methylenebiscyclohexylamine) (nylon PACMT), poly (isophthaloyl 4, 4 '-methylenebiscyclohexylamine) (nylon PACMI), polydodecamide 4, 4' -methylenebiscyclohexylamine (nylon PACM12), or copolymers of the above polymers.

In order to obtain a terminal-modified polyamide resin having a good crystallinity, the polyamide main chain structure of the terminal-modified polyamide resin is preferably polycaprolactam (nylon 6), polyhexamethylene adipamide (nylon 66), polypentylene adipamide (nylon 56), polytetramethylene sebacamide (nylon 410), polypentylene sebacamide (nylon 510), polyhexamethylene sebacamide (nylon 610), polyparanonanediyl terephthalamide (nylon 9T), or polyparadecanediyl terephthalamide (nylon 10T).

The main chain structure of the terminal-modified polyamide resin may be composed of one of the main chain structures described above alone, or may be composed of a combination of two or more of the main chain structures described above. The terminal-modified polyamide resin used in the present invention preferably has 80 mol% or more of the repeating units in the main chain thereof composed of the structural units derived from the monomer raw materials as exemplified above (the number of repeating units in the main chain structure of the polyamide is 100 mol%). In view of heat resistance and crystallinity, it is preferably 90 mol% or more, and most preferably 100 mol%.

The flexible polyether structure shown in the formula I is introduced into the tail end of the polyamide, so that the whole mobility of a molecular chain is improved, and the melt viscosity is reduced. Therefore, when the thermoplastic resin containing the terminal modified polyamide resin is contacted with the metal in a molten state, the resin melt can be more effectively infiltrated into the tiny holes on the surface of the metal, so that the metal surface can be better and tightly jointed.

In the formula I, n is an integer of 2-100. When n is less than 2, the effect of lowering the melt viscosity of the thermoplastic resin composition is deteriorated. Preferably, n is 4 or more, more preferably n is 8 or more, and most preferably n is 16 or more. On the other hand, when n is more than 100, the heat resistance of the terminal structure represented by formula I is deteriorated. Preferably, n is 70 or less, more preferably, n is 50 or less, and most preferably, n is 25 or less.

In the above formula I, R₁The same or different alkylene groups are those having 2 to 10 carbon atoms. R₁Specifically, it may include-CH₂-CH₂-、-CH₂-CH₂-CH₂-、-CH(CH₃)-CH₂-、-CH₂-CH₂-CH₂-CH₂-、-CH₂-CH₂-CH₂-CH₂-CH₂-or-CH₂-CH₂-CH₂-CH₂-CH₂-CH₂-and the like. In view of affinity with the polyester main chain structure, R is preferably₁Is alkylene having 2 to 6 carbon atoms, furtherIn step (b), an alkylene group having 2 to 4 carbon atoms is preferable. R₁May be formed by a combination of different alkylene groups, preferably-CH₂-CH₂-、-CH₂-CH₂-CH₂-、-CH(CH₃)-CH₂-at least one of.

In the above formula I, R₂Is an alkyl group having 1 to 30 carbon atoms. R₂The smaller the number of carbon atoms, the higher the affinity thereof for the polyamide backbone structure, and therefore R₂The alkyl group having 1 to 20 carbon atoms is preferable, the alkyl group having 1 to 10 carbon atoms is more preferable, the alkyl group having 1 to 5 carbon atoms is even more preferable, and the methyl group is most preferable.

In the formula I, X-is-NH-, -O-, -C (═ O) -, -NH-C (═ O) -O-, -NH-C (═ O) -NH-or-CH (OH) -CH₂Any of-X-preferably-NH-in order to give the thermoplastic resin composition used in the present invention a low melt viscosity, preferably a high affinity of the polyether terminal to the polyamide main chain.

The content of the terminal structure represented by formula I in the terminal-modified polyamide resin used in the present invention is 0.05 to 20 wt% based on the total weight of the terminal-modified polyamide resin, and the content of the terminal structure in the terminal-modified polyamide resin is preferably 0.1 wt% or more, more preferably 0.5 wt% or more, still more preferably 1.5 wt% or more, and most preferably 2 wt% or more, for the purpose of lowering melt viscosity and improving molding processability; on the other hand, by setting the content of the terminal structure represented by formula I to 20 wt% or less, the crystallinity and mechanical properties of the terminal-modified polyamide resin can be maintained better, preferably 15 wt% or less, more preferably 10 wt% or less, and still more preferably 5 wt% or less. Here, the content (wt%) of the polyether segment represented by the above formula I relative to the terminal-modified polyamide resin is determined by¹H-NMR (nuclear magnetic hydrogen spectrum) test.

The terminal-modified polyamide resin having a terminal structure represented by formula I is preferably 1.1 to 5.0 in terms of relative viscosity η r measured at 25 ℃ when a solution having a concentration of 0.01g/ml is prepared using 96 wt% concentrated sulfuric acid as a solvent. When η r is less than 1.1, the mechanical properties and metal bonding properties of the thermoplastic resin composition tend to be lowered. Preferably, η r is 1.2 or more, and more preferably 1.4 or more. On the other hand, when η r is higher than 5.0, the molecular weight is too high, and the melt viscosity tends to be too high, and the metal joining performance tends to be lowered, and η r is preferably 4 or less, and more preferably 3 or less.

The weight average molecular weight (Mw) of the terminal-modified polyamide resin having a terminal structure represented by formula I in the present invention is preferably 10,000 or more. When Mw reaches 10,000 or more, mechanical properties and metal bonding properties are improved. The Mw is more preferably 20,000 or more, still more preferably 30,000 or more. Further, Mw is preferably 40 ten thousand or less. When Mw is 40 ten thousand or less, the melt viscosity is low, and the resin melt can sufficiently infiltrate minute pores on the metal surface in the process of producing the joined body, so that the thermoplastic resin composition can be tightly joined to the metal surface, and the metal joining performance can be improved. The Mw is more preferably 30 ten thousand or less, still more preferably 25 ten thousand or less. The weight average molecular weight (Mw) can be determined by Gel Permeation Chromatography (GPC).

In the present invention, since it is intended to obtain a joined body having good heat resistance, the melting point (Tm) of the terminal-modified polyamide resin having a terminal structure represented by the formula I is preferably 215 ℃ or higher, and more preferably 218 ℃ or higher. Generally, the melting point of a polyamide resin is lowered by introducing a flexible structure into the polyamide resin by copolymerization, but the present invention minimizes lowering of the melting point of a polyamide resin having polyether terminals introduced therein, as compared with a polyamide resin not having a polyether terminal structure, by selectively introducing a polyether having a specific structure into the resin terminals. The melting point decrease is preferably not more than 5 ℃ and more preferably not more than 3 ℃. The melting point of the polyamide resin described herein is determined by Differential Scanning Calorimetry (DSC): the polyamide resin is precisely weighed to be 5-7 mg, the polyamide resin is heated from 20 ℃ to a temperature higher than the temperature T0 of an endothermic peak by 30 ℃ at a heating rate of 20 ℃/min in a nitrogen atmosphere, the polyamide resin is kept at the temperature for 2min, then the polyamide resin is cooled to 20 ℃ at a cooling rate of 20 ℃/min, then the polyamide resin is heated to a temperature higher than the temperature T0 by 30 ℃ at a heating rate of 20 ℃/min, and the temperature of the endothermic peak occurring in the second heating process is defined as a melting point (Tm).

The thermoplastic resin composition used in the present invention may be compounded by adding other polymers, fillers, and various additives in addition to the terminal-modified polyamide resin.

Examples of other polymers in the thermoplastic resin composition include, but are not limited to, the following: polyolefins such as polyethylene and polypropylene; modified polyolefins such as copolymers obtained by polymerizing olefin and/or conjugated diene compounds; polyester, polycarbonate, polyphenylene ether, polyphenylene sulfide, liquid crystal polymer, polysulfone, polyethersulfone, ABS resin, SAN resin, polystyrene, polyamide resin other than the terminal unmodified polyamide resin of the present invention, and the like.

As the other polymer, in order to improve the impact resistance and reduce the shrinkage of the molded article obtained from the thermoplastic resin composition used in the present invention, it is preferable to use a shock-resistant agent such as a modified polyolefin, for example, a polymer (or copolymer) obtained by polymerizing an olefin and/or a conjugated diene compound.

The above-mentioned polymer (or copolymer) may be exemplified by, but not limited to, the following examples: a vinyl copolymer, a conjugated diene polymer, a conjugated diene-aromatic vinyl copolymer, or the like.

The ethylene copolymer means a copolymer of ethylene and other monomers. Other monomers copolymerizable with ethylene may be exemplified by, but not limited to, the following examples: alpha-olefin having 3 or more carbon atoms, non-conjugated diene, vinyl acetate, vinyl alcohol, alpha, beta-unsaturated carboxylic acid, or a derivative thereof. The above-mentioned monomer may be copolymerized with ethylene in an amount of 2 or more species.

The α -olefin having 3 or more carbon atoms includes, but is not limited to, the following examples: propylene, 1-butene, 1-pentene or 3-methyl-1-pentene, preferably propylene or 1-butene. Examples of non-conjugated dienes include, but are not limited to, the following: norbornene compounds such as 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-propenyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-butenyl-2-norbornene, 5- (2-methyl-2-butenyl) -2-norbornene, 5- (2-ethyl-2-butenyl) -2-norbornene and 5-methyl-5-vinylnorbornene; dicyclopentadiene, methyltetrahydroindene, tetrahydroindene, 1, 5-cyclooctadiene, 1, 4-hexadiene, 6-methyl-1, 5-heptadiene, or 11-tridecadiene, etc., preferably 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, dicyclopentadiene, or 1, 4-hexadiene. The α, β -unsaturated carboxylic acids may be exemplified by, but not limited to, the following: acrylic acid, methacrylic acid, ethacrylic acid, 2-butenoic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, butenedioic acid, or the like. The derivatives of α, β -unsaturated carboxylic acids include, but are not limited to, the following examples: alkyl esters, aryl esters, glycerides, anhydrides, imides of the above-mentioned α, β -unsaturated carboxylic acids, and the like.

The conjugated diene-based polymer refers to a polymer obtained by polymerizing at least one conjugated diene. The conjugated diolefins mentioned here can be mentioned by way of example and not by way of limitation: 1, 3-butadiene, isoprene (2-methyl-1, 3-butadiene), 2, 3-dimethyl-1, 3-butadiene, 1, 3-pentadiene, and the like. The conjugated diene may be copolymerized by selecting 2 or more species. In addition, the unsaturated bonds of the polymer may be partially or completely reduced by hydrogenation.

The conjugated diene-aromatic vinyl copolymer refers to a copolymer of a conjugated diene and an aromatic vinyl, and may be a block copolymer or a random copolymer. Examples of the conjugated diene are the same as those of the above-mentioned raw materials for producing the conjugated diene polymer, and 1, 3-butadiene and isoprene are preferable. The following examples of aromatic vinyl are given: styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 1, 3-dimethylstyrene, vinylnaphthalene, or the like, with styrene being preferred. In addition, the unsaturated bond other than the double bond of the aromatic ring of the conjugated diene-aromatic vinyl copolymer may be partially or completely reduced by hydrogenation.

Examples of the impact-resistant agent include: ethylene/propylene copolymers, ethylene/1-butene copolymers, ethylene/1-hexene copolymers, ethylene/propylene/dicyclopentadiene copolymers, ethylene/propylene/5-ethylidene-2-norbornene copolymers, unhydrogenated or hydrogenated styrene/isoprene/styrene triblock copolymers, unhydrogenated or hydrogenated styrene/butadiene/styrene triblock copolymers, ethylene/methacrylic acid copolymers or copolymers in which some or all of the carboxylic acid groups have been formed with sodium, lithium, potassium, zinc or calcium, ethylene/methyl acrylate copolymers, ethylene/ethyl acrylate copolymers, ethylene/methyl methacrylate copolymers, ethylene/ethyl acrylate-g-maleic anhydride copolymers (where "g" denotes grafting, the same applies to the following), ethylene/methyl acrylate-g-maleic anhydride copolymer, ethylene/ethyl acrylate-g-maleimide copolymer, ethylene/ethyl acrylate-g-N-phenylmaleimide copolymer or partially saponified product of the copolymer, ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, ethylene/methyl methacrylate/glycidyl methacrylate copolymer, ethylene/glycidyl acrylate copolymer, ethylene/vinyl acetate/glycidyl acrylate copolymer, ethylene/glycidyl ether copolymer, ethylene/propylene-g-maleic anhydride copolymer, ethylene/ethyl acrylate-g-maleic anhydride copolymer, ethylene/propylene-g-maleic, Ethylene/butene-1-g-maleic anhydride copolymer, ethylene/propylene/1, 4-hexadiene-g-maleic anhydride copolymer, ethylene/propylene/dicyclopentadiene-g-maleic anhydride copolymer, ethylene/propylene/2, 5-norbornadiene-g-maleic anhydride copolymer, ethylene/propylene-g-N-phenylmaleimide copolymer, ethylene/butene-1-g-N-phenylmaleimide copolymer, hydrogenated (styrene/butadiene/styrene-g-maleic anhydride) copolymer, hydrogenated (styrene/isoprene/styrene-g-maleic anhydride) copolymer, ethylene/propylene-g-N-phenylmaleimide copolymer, ethylene/butene-1-g-N-phenylmaleimide copolymer, ethylene/butadiene/styrene-g-maleic anhydride copolymer, ethylene/isoprene/styrene-g-maleic anhydride copolymer, ethylene/propylene/butadiene/styrene-, Ethylene/propylene-g-glycidyl methacrylate copolymer, ethylene/butene-1-g-glycidyl methacrylate copolymer, ethylene/propylene/1, 4-hexadiene-g-glycidyl methacrylate copolymer, ethylene/propylene/dicyclopentadiene-g-glycidyl methacrylate copolymer, hydrogenated (styrene/butadiene/styrene-g-glycidyl methacrylate) copolymer, nylon 12/polytetrahydrofuran copolymer, nylon 12/polypropylene glycol copolymer, polybutylene terephthalate/polytetrahydrofuran copolymer, polybutylene terephthalate/polypropylene glycol copolymer, and the like. The copolymer is preferably ethylene/methacrylic acid copolymer, salt formed by partial or all carboxylic acid groups in the copolymer and sodium, lithium, potassium, zinc or calcium, ethylene/propylene-g-maleic anhydride copolymer, and ethylene/butylene-1-g-maleic anhydride copolymer.

The polymer other than the terminal-modified polyester resin in the thermoplastic resin composition may be added alone, or two or more kinds may be selected and added. The amount of the thermoplastic resin composition added is preferably 0 wt% or more and 80 wt% or less (based on 100 wt% of the thermoplastic resin composition), and by controlling the amount of the thermoplastic resin composition added in the above range, the thermoplastic resin composition can be made to have better fluidity when melted. More preferably 60 wt% or less, and still more preferably 50 wt% or less.

The thermoplastic resin composition of the present invention may further contain a filler, and examples of the filler include, but are not limited to, the following: fibrous inorganic or organic fillers such as glass fibers, carbon fibers, potassium titanate whiskers, zinc oxide whiskers, aluminum borate whiskers, aramid fibers, alumina fibers, silicon carbide fibers, ceramic fibers, asbestos fibers, gypsum fibers, or metal fibers; wollastonite, zeolite, sericite, kaolin, mica, talc, clay, pyrophyllite, bentonite, montmorillonite, asbestos, silicate, alumina, silica, magnesia, zirconia, titania, iron oxide, calcium carbonate, magnesium carbonate, dolomite, calcium sulfate, barium sulfate, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, glass beads, ceramic beads, boron nitride, silicon carbide, or silica. The filler may be hollow, and the filler may be treated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organoborane compound, or an epoxy compound. The montmorillonite can also be organic montmorillonite in which the interlayer ions are subjected to cation exchange through organic ammonium salt. The filler is preferably a fibrous inorganic filler, and more preferably glass fiber or carbon fiber, in view of improvement in mechanical properties and reduction in molding shrinkage of the thermoplastic resin composition. The filler may be added alone or in combination of two or more.

The content of the filler in the thermoplastic resin composition is preferably 5 to 80 wt% based on the total weight of the thermoplastic resin composition, and when the amount of the filler is 5 wt% or more, since the shrinkage of the thermoplastic resin composition decreases, in the process of producing a joined body, after the melt of the thermoplastic resin composition is brought into contact with a metal and cooled, interfacial peeling between the thermoplastic resin composition and the metal is suppressed, and the bondability between the thermoplastic resin composition and the metal is enhanced, and more preferably, the amount of the filler is 10 wt% or more, even more preferably 20 wt% or more, and most preferably 30 wt% or more based on the total weight of the thermoplastic resin composition. On the other hand, when the amount of the filler added is 80 wt% or less, the thermoplastic resin composition melt has good fluidity, more preferably 60 wt% or less, and still more preferably 50 wt% or less.

The thermoplastic resin composition used in the present invention may further contain various additives. For example, antioxidants and heat stabilizers (hindered phenol type, p-phenylene type, phosphite type, phosphate type and substitution products thereof, copper halide, iodine compounds, etc.), weather resistant agents (resorcinol type, salicylic acid type, benzotriazole type, diphenyl ketone type, hindered amine type, etc.), mold release agents and lubricants (fatty alcohol, fatty amide, fatty diamide, diurea, polyethylene wax, etc.), pigments (calcium sulfide, phthalocyanine, carbon black, etc.), dyes (nigrosine, etc.), plasticizers (N-octyl p-hydroxybenzoate or N-butylbenzenesulfonamide), antistatic agents (alkylsulfate type anionic antistatic agents, 4-stage ammonium salt type cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, or trimethylglycine type amphoteric antistatic agents), flame retardants (melamine cyanurate, hydroxides such as magnesium hydroxide and aluminum hydroxide, bromine-based flame retardants such as ammonium polyvinyl phosphate, brominated polystyrene, brominated polyphenylene oxide, brominated polycarbonate, and brominated epoxy resin, or a combination of the above bromine-based flame retardants and antimony trioxide). The additive can be used alone or more than 2 additives can be selected for compounding.

The present invention aims to obtain a joined body having excellent joining performance between a thermoplastic resin composition and a metal, and therefore it is preferable to use a thermoplastic resin composition having a tensile shear strength of 10MPa or more in joining a thermoplastic resin composition comprising a terminal-modified polyamide resin having a terminal structure represented by formula I with aluminum. The tensile shear strength is defined as the value determined at a tensile speed of 5mm/min according to the adapter test bars specified in ISO19095 (FIG. 1). The surface of the aluminum used herein has a microporous structure with an average pore diameter of 10 to 100nm, and the texture of the surface of the aluminum can be observed by an electron scanning microscope. Further preferred is a thermoplastic resin composition having a tensile shear strength of 15MPa or more, most preferred is a thermoplastic resin composition having a tensile shear strength of 20MPa or more, wherein the tensile shear strength of the thermoplastic resin composition for metal bonding is determined by preparing test specimens according to ISO19095 and testing at a tensile speed of 5 mm/min.

The joined body in the present invention can be obtained by directly joining the thermoplastic resin composition and the metal, that is, the thermoplastic resin composition and the metal can be directly joined without an intermediate layer such as another adhesive. The metal may be surface-treated or not, and the kind of the metal is not particularly limited, and examples thereof include iron, copper, silver, gold, aluminum, zinc, lead, tin, magnesium, and alloys of the above metals, such as stainless steel. The metal surface may have an oxide layer, the surface may be subjected to surface treatment to form a concave-convex structure, or an organic functional group or a low-molecular-weight organic compound may be introduced into the metal surface to form a chemical structure layer.

Examples of the method of surface treatment of the metal include a method in which a metal surface is immersed in a corrosive liquid, a fine uneven structure is etched on the surface, and then the surface is immersed in a nitrogen-containing compound aqueous solution or fumigated with a nitrogen-containing compound gas to attach a chemical substance to the metal surface; a method of immersing a metal surface in a corrosive liquid, anodizing the metal surface to form a fine uneven structure on the metal surface, and attaching a chemical substance to the metal surface; a method of etching a groove by laser processing, and the like. Specifically, the surface treatment method may be a surface treatment method of NMT by PLAS corporation, a surface treatment method of TRI by east asian electric power company, or the like.

The corrosive liquid used for the surface treatment may, for example, be an aqueous alkaline solution (pH > 7), an aqueous acidic solution (pH < 7), an aqueous solution of a nitrogen-containing compound, and the like, and the aqueous alkaline solution may, for example, be an aqueous solution of sodium hydroxide, potassium hydroxide, sodium carbonate, and the like; examples of the acidic aqueous solution include aqueous solutions of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, and the like; the nitrogen-containing compound may be ammonia, hydrazine or a water-soluble amine, and specific examples of the water-soluble amine include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, allylamine, ethanolamine, diethanolamine, triethanolamine, aniline and other amines.

The metal surface anodizing method includes, for example, forming an oxide film on the metal surface by passing a current through an electrolytic solution using a metal as an anode, and, for example, a water-soluble amine composition may be used as the electrolytic solution for anodizing the metal surface.

Examples of the chemical substance to be attached to the metal surface include ammonia, hydrazine, water-soluble amine, and triazine dithiol compound.

The method of etching the groove by laser processing may be, for example, DLAMP technology developed by macleaux and macleaux, japan, and technology for forming a micro hole by etching a metal surface.

The nanoscale concave-convex structure on the metal surface is a nanoscale microporous structure under an electron scanning microscope, the average pore diameter is preferably 10-100 nm, and the pore diameter is further preferably 10-80 nm.

The present invention also provides a method for producing a joined body of the thermoplastic resin composition of the present invention and a metal. The present invention is not particularly limited to the method for producing the joined body, and the method for producing the joined body will be described below by way of example.

In view of improving the bondability between the thermoplastic resin composition and the metal and the efficiency in the actual production process, injection molding or welding by laser irradiation is preferable.

Specific examples of the injection molding method include a method in which a thermoplastic resin composition is heated to melt and then injection molded into a mold previously placed in a metal to obtain a joined body. In the injection molding process, the mold temperature is not particularly limited, but is preferably 60 ℃ to 180 ℃. The bonding property between the thermoplastic resin composition and the metal can be improved by controlling the mold temperature to 60 ℃ or higher, more preferably 80 ℃ or higher, and still more preferably 100 ℃ or higher; on the other hand, the thermoplastic resin composition can be cured and molded more efficiently at a mold temperature of 180 ℃ or lower, and is preferably 160 ℃ or lower, and more preferably 150 ℃ or lower.

As a method of welding by laser irradiation, specifically, there is a method of fixing a molded article made of a thermoplastic resin composition and a metal by stacking them, and then irradiating the molded article or the metal with laser light from the resin side or the metal side to melt the resin in the vicinity of the contact interface between the resin and the metal material, thereby joining the resin molded article and the metal material.

The bonded body of the thermoplastic resin composition and the metal has high bonding property, and is suitable for the fields of automobile parts, electronic and electric product parts, structural materials and the like which need to be bonded by the metal.

Drawings

FIG. 1: the bonding sample of resin and metal used in the examples of the present invention was tested for the bondability of resin and metal.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to these examples.

The tests involved in the examples and comparative examples are illustrated below:

(1) relative viscosity η r: the polyamide resin samples used in the respective examples and comparative examples were dissolved in 96 wt% concentrated sulfuric acid to prepare solutions having a polyamide resin concentration of 0.01g/ml, and the relative viscosities were measured at 25 ℃ with an Ubbelohde viscometer.

(2) The content of the terminal structure shown in the formula I: the polyamide resin having the terminal structure represented by the above formula I used in each of examples and comparative examples was dissolved in deuterated concentrated sulfuric acid at a concentration of 50mg/ml, and subjected to JEOL ECX400P under conditions of 256 scans¹H-NMR nuclear magnetic test. To pair¹H-NMR spectrum of-CH in the above formula I in which the terminal structure is adjacent to oxygen of ether bond₂The peak corresponding to hydrogen in (a) and the peak corresponding to hydrogen in the main chain repeating unit of the polyamide as the main component are assigned, and the content of the terminal structure represented by the formula (I) in the polyamide resin is calculated from the peak area obtained by integrating the peaks and the number of hydrogen atoms contained in each structure.

(3) Thermal performance

By using a differential scanning calorimeter (DSC Q2000) of the company TA, 5-7 mg of the thermoplastic resin composition used in each of the examples and comparative examples was precisely weighed, the temperature was raised from 20 ℃ to a temperature 30 ℃ higher than the temperature T0 of the endothermic peak at a temperature rise rate of 20 ℃/min in a nitrogen atmosphere, the temperature was maintained at the temperature for 2min, the temperature was then lowered to 20 ℃ at a temperature lowering rate of 20 ℃/min, the temperature was maintained at 20 ℃ for 2min, and then the temperature was again raised to a temperature 30 ℃ higher than T0 at a temperature raising rate of 20 ℃/min to obtain a melting point T0_m。T_mThe temperature corresponding to the peak tip of the endothermic peak in the secondary heating process.

(4) Molecular weight

2.5mg of the resin portion of the polyamide resin particles obtained in each preparation example or the joined body obtained after injection molding in each example and comparative example were dissolved in 4ml of hexafluoroisopropanol containing 0.0075N sodium trifluoroacetate, and the resultant solution was filtered through a 0.45 μm filter, and the number-average molecular weight Mn and the weight-average molecular weight Mw were measured under the following conditions:

a pump: e-Alliance GPC system (Waters system)

A detector: differential detector Waters 2414 (made by Waters)

A chromatographic column: shodex HFIP-806M (2 roots) + HFIP-LG

Solvent: hexafluoroisopropanol (sodium trifluoroacetate with addition of 0.0075N)

Flow rate: 0.5ml/min

Sample injection amount: 0.1ml

Temperature: 40 deg.C

And (3) correcting the molecular weight: polymethyl methacrylate.

(5) Melt viscosity

The polyamide resins obtained in preparation examples 1 to 12 were dried in a vacuum drying oven at 80 ℃ for 12 hours or more, then hot-pressed into films (film thickness 0.7mm) by a film press, cut into 25 mm-diameter wafers, and melt viscosity was measured by a rotational rheometer (MCR 302, parallel plate # 25, manufactured by antonaar) by the following method: the sample was melted at 260 ℃ (preparations 1 to 7, 10 to 12) or 280 ℃ (preparations 8 and 9) for 5 minutes under nitrogen atmosphere, the distance between parallel plates was 0.5mm, vibration mode measurement, frequency was 0.5 to 6.88Hz, measurement was 50 points (0.5 minutes), and amplitude was 1%. The melt viscosity was determined as the complex viscosity at a frequency of 1 Hz.

(6) Tensile Strength/tensile modulus

The tensile modulus of the terminal-modified polyamide obtained in preparation example 3 and the commercial polyamide elastomer used in comparative examples 4 and 5 were measured according to ASTM D638 with a bar size of TypeIV in ASTM D638 using Shimadzu AG-IS 1KN, a test temperature of 23 ℃, a humidity of 50% RH, a tensile speed of 10mm/min, and a clip pitch of 60 mm. The tensile modulus results were averaged over the 5-spline test results. The injection molding conditions of the specimens were as follows:

an injection molding machine: ST10S2V (NISSEI)

Screw temperature: 250 deg.C

Temperature of the die: 80 deg.C

(7) Metal sheet

Aluminum sheet a6061(45mm x 10mm x 1.5mm) kunshanxin die ltd.

Aluminum sheet processing company entrusted: shenzhen Baoyuan gold Ltd (NMT processing);

shenzhen jin hong Xin science and technology limited (TRI processing).

(8) Conjugant injection molding

The metal sheet was placed in the cavity of a mold, and after holding the mold closed for 1 minute, the melt of the thermoplastic resin composition was metered and injected into the mold. And opening the mold after the melt is cooled and solidified to obtain the conjugant.

An injection molding machine: ST10S2V (NISSEI)

Screw temperature: 260 deg.C (examples 1 to 11, comparative examples 1 to 6)

280 deg.C (example 12, comparative example 7)

Temperature of the die: 60-120 DEG C

(9) Bonding property

The bondability of the resin and the metal is characterized by a tensile shear strength, and according to the test of ISO19095 standard, the size of the sample bar is specified in ISO19095 shown in figure 1, and the bonding area is 0.5cm²The tensile modulus was measured by using the Shimadzu AG-IS 1KN at a temperature of 23 ℃, a humidity of 50% RH, a tensile rate of 5mrm/min and a clamp pitch of 3 mm. The tensile shear strength results were averaged over the 5 bar test results.

The following description will be made of the methods for producing a non-terminal-modified polyamide resin and a terminal-modified polyamide resin having a structure represented by formula I:

raw materials used in preparation examples:

caprolactam: BASF

Polyether amine: JEFFAMINE M1000(Mn 1000) from Huntsman and having a structure shown in formula II

Formula II

Adipic acid: alfa

1, 6-hexamethylenediamine: TCI

Preparation example 1

500g of caprolactam, 0.19g of adipic acid, 2.6g of JEFFAMINE M1000(Mn 1000) and 150g of deionized water were placed in a reaction vessel, which was then sealed and purged with nitrogen three times. The temperature of the heater of the reaction vessel was set to 290 ℃ and then heating was started. When the pressure in the reaction kettle reaches 1MPa, releasing the water vapor in the reaction kettle through an air release valve, and simultaneously maintaining the pressure in the kettle at 1MPa until the temperature in the kettle is raised to 250 ℃. When the temperature in the kettle reaches 250 ℃, the temperature set by the heater is reduced to 260 ℃, and the pressure in the kettle is gradually reduced from 1MPa to the normal pressure within 1 hour (the temperature in the kettle is 260 ℃ when the normal pressure is reached). After the pressure was reduced to normal pressure, a nitrogen stream was introduced into the reactor, and melt polymerization was carried out under the nitrogen stream for 30 minutes (the maximum temperature reached to 263 ℃ C.), the polymer melt was spouted into a long strand through a spout valve and cooled with cooling water and then pelletized to obtain product particles. Removing small molecules in the polymer by using methanol as a solvent in a Soxhlet extractor, and drying in a vacuum oven at 80 ℃ for 24h to obtain the end modified N6 containing the structure shown in the formula I.

Preparation examples 2 to 7

The operation was the same as in preparation example 1 except that the raw materials were changed as shown in Table 1 and the nitrogen gas introducing time after the pressure in the autoclave reached the atmospheric pressure was changed as shown in Table 1.

Preparation example 8

381.64g of adipic acid, 302.11g of 1, 6-hexanediamine, 23.6g of JEFFAMINE M1000(Mn 1000) and 180g of deionized water were put into a reaction vessel, and the reaction vessel was sealed and then replaced with nitrogen gas three times. The heating was started after the temperature of the heater of the reaction vessel was set to 210 ℃. After the reaction is carried out for 1.5 hours, the temperature of a heater of the reaction kettle is set to 300 ℃, when the pressure in the reaction kettle reaches 1.75MPa, the pressure in the reaction kettle is maintained at 1.75MPa while releasing the water vapor in the reaction kettle through a vent valve until the temperature in the reaction kettle is increased to 250 ℃. When the temperature in the autoclave reached 250 ℃, the pressure in the autoclave was gradually reduced from 1.75MPa to normal pressure within 1 hour (the temperature in the autoclave reached 270 ℃). After the pressure was reduced to normal pressure, a nitrogen stream was introduced into the reactor, and melt polymerization was carried out under the nitrogen stream for 20 minutes (maximum reaching temperature 283 ℃ C.), the polymer melt was spouted into a long strand through a spout valve and cooled by cooling water and then pelletized to obtain product particles. The resulting particles were dried in a vacuum oven at 80 ℃ for 24h to give N66 containing a terminal modification of the structure shown in formula I.

Preparation example 9

The operation was the same as in preparation example 8 except that the raw materials were changed as shown in Table 1 and the nitrogen gas introducing time after the pressure in the autoclave reached the atmospheric pressure was changed as shown in Table 1.

TABLE 1

In production example 6, it is assumed that the polymer molecular weight could not be increased due to the excessive addition amount of the polyetheramine, because the product particles could not be obtained because the terminal-modified polyamide resin could not be stretched into a long strand when discharged from the reaction vessel.

Preparation examples 10 to 12

The raw materials were weighed as shown in table 2. The raw materials were mixed in a high-speed mixer, and then fed from a main feed port of a twin-screw extruder (L/D45.5) model TEX30 α manufactured by japan steelworks, and melt-kneaded at a screw temperature of 250 ℃ and a screw rotation speed of 200 rpm. The extruded strand was pelletized and then vacuum-dried at 80 ℃ for 24 hours to obtain a polyamide resin composition.

TABLE 2

Example 1

The metal sheet subjected to surface treatment (NMT treatment, Shenzhen Baoyuan gold Co., Ltd.) is placed in a mold of an ST10S2V (manufactured by NISSEI) injection molding machine, the injection molding machine finishes metering the modified polyamide resin containing the terminal end of the structure shown in I obtained in the preparation example 1, the resin melt is injected into the mold, the cooling time is 15S, the mold is opened, and the conjugant is obtained, wherein in the molding process, the screw temperature is 260 ℃, and the mold temperature is 120 ℃. The joined body obtained in the above manner was subjected to a metal joining performance test at a drawing speed of 5mm/min in accordance with ISO19095, and the results are shown in Table 3.

Examples 2 to 7

The same operations as in example 1 were carried out except that the kind of the terminal-modified polyamide was changed as shown in Table 3, and the properties of the obtained joined body were as shown in Table 3.

Comparative example 1

Placing the metal sheet subjected to surface treatment (NMT treatment, Shenzhen Baoyuan gold Co., Ltd.) in a mold of an ST10S2V (manufactured by NISSEI) injection molding machine, after the injection molding machine finishes metering the polyamide which is obtained in the preparation example 7 and is not subjected to terminal modification, injecting a resin melt into the mold, cooling for 15S, and opening the mold to obtain a conjugant, wherein the temperature of a screw is 260 ℃ and the temperature of the mold is 120 ℃ in the molding process. The joined body obtained by the above method was subjected to a metal joining performance test at a drawing speed of 5mm/min in accordance with ISO19095, and the results are shown in Table 3.

TABLE 3

Compared with comparative example 1, the tensile shear strength of the thermoplastic resin composition containing the structure end modified polyamide shown in formula I in metal bonding is better than that of the thermoplastic resin composition without the structure polyamide shown in formula I, and the tensile shear strength of the metal bonding of examples 2 to 6 is obviously higher than that of examples 1 and 7 with lower structure content shown in formula I. For example 4, higher levels of the structure of formula I had an effect on the mechanical strength of the end-modified polyamide resin bulk such that the metal bond tensile shear strength was lower than for examples containing 2 wt% and 4 wt% of the ends of the structure of formula I. For examples 5, 6, the resulting thermoplastic resin compositions had lower melt viscosities (Table 2) by blending the polyamide resin containing a higher content of the terminally modified polyamide resin having the structure of formula I with the polyamide resin not containing the structure of formula I, resulting in a resulting joint having higher tensile shear strength for metal joints.

Examples 8 to 10

The operation was the same as in example 3 except that the mold temperature during injection molding was changed as shown in Table 4, and the properties of the resulting joined body were as shown in Table 4.

Comparative examples 2 and 3

The same operations as in comparative example 1 were carried out except that the mold temperature during injection molding was changed as shown in Table 4, and the properties of the resulting joined body were as shown in Table 4.

TABLE 4

Comparing example 8 with comparative example 2, and example 9 with comparative example 3, it can be seen that the metal bond tensile shear strength of examples 3 and 8, which contain 4 wt% of the structure end modified polyamide resin represented by formula I, is higher than that of examples 9 and 10, which are molded under the condition of higher mold temperature.

Comparative example 4

The metal sheet subjected to surface treatment (NMT treatment, Shenzhen Baoyuan gold Co., Ltd.) is placed in a mold of an ST10S2V (manufactured by NISSEI) injection molding machine, after the injection molding machine finishes measuring a commercial polyamide elastomer (PEBAX 5533SP01, manufactured by Arkema), a resin melt is injected into the mold, the cooling time is 15S, the mold is opened, and a conjugant is obtained, wherein in the molding process, the screw temperature is 260 ℃ and the mold temperature is 60 ℃. The joined body obtained by the above method was subjected to a metal joining performance test at a drawing speed of 5mm/min in accordance with ISO19095, and the results are shown in Table 5.

Comparative example 5

The procedure was identical to that of comparative example 4, except that the mold temperature during injection molding was changed to 120 ℃ as shown in Table 5. However, the resin was not sufficiently cured in the mold, and the test specimen could not be obtained because the resin was deformed during the mold release.

TABLE 5

Data from Shannon Armstrong, Benny Freeman, ane Hiltner, ericbaer. polymer; 2012: 1383-1392.

Example 3 is superior in high temperature formability and has higher tensile shear strength of metal bonding than comparative example 5. Meanwhile, compared with the comparative example 4, the metal joint of the example 10 has higher tensile shear strength. In addition, the tensile strength and tensile modulus of the thermoplastic resin composition bodies in examples 3 and 10 are significantly superior to those of the polyamide elastomers in comparative examples 4 and 5.

Example 11

The same operation as in example 3 was carried out except that the metal sheets treated by the different surface treatment method (TRI treatment, Shenzhen Jinhongchen technology, Ltd.) were used as shown in Table 6, and the properties of the obtained joined body were as shown in Table 6.

Comparative example 6

Except that the metal pieces treated by the different surface treatment methods (TRI treatment, Shenzhen Jinhongchen science and technology Co., Ltd.) were used as shown in Table 6, the operation was the same as that of comparative example 1, and the properties of the obtained joined body were as shown in Table 6.

TABLE 6

From examples 3 and 11, it can be seen that the tensile shear strength of the joint between the end-modified polyamide resin having a structure represented by formula I in an amount of 4 wt% and the metal treated in both NMT and TRI treatments reached 20MPa or more. In comparative examples 1 and 6 in which a polyamide resin having no terminal modification was used, the tensile strength of the bond between the resin and the metal treated in both NMT and TRI treatments was less than 10 MPa.

Example 12

The metal sheet subjected to surface treatment (NMT treatment, Shenzhen Baoyuan gold Co., Ltd.) is placed in a mold of an ST10S2V (manufactured by NISSEI) injection molding machine, the injection molding machine finishes metering the modified polyamide resin containing the terminal end of the structure shown in I obtained in the preparation example 8, the resin melt is injected into the mold, the cooling time is 15S, the mold is opened, and the conjugant is obtained, wherein the screw temperature is 280 ℃ and the mold temperature is 120 ℃ in the molding process. The joined body obtained in the above manner was subjected to a metal joining performance test at a drawing speed of 5mm/min in accordance with ISO19095, and the results are shown in Table 7.

Comparative example 7

The same operations as in example 12 were carried out except that the kind of the terminal-modified polyamide was changed as shown in Table 7, and the properties of the obtained joined body were as shown in Table 7.

TABLE 7

In example 12, it can be seen that the tensile shear strength of the metal bond of the thermoplastic resin composition containing the polyamide having a modified terminal structure represented by formula I is superior to that of the composition containing no polyamide having a structure represented by formula I, as compared with comparative example 7.

Claims

1. A joined body of a thermoplastic resin composition and a metal, characterized in that: the thermoplastic resin composition contains terminal modified polyamide resin, the content of the terminal modified polyamide resin is 5-100 wt% of the total weight of the thermoplastic resin composition, the terminal modified polyamide resin has a terminal structure shown in a formula I,

-X-(R₁-O)n-R₂formula I

2. The junction body according to claim 1, wherein: in the terminal structure shown in the formula I, n is an integer of 16-50.

3. The junction body according to claim 1, wherein: in the terminal structure shown in the formula I, n is an integer of 16-25.

4. The junction body according to claim 1, wherein: in the terminal structure represented by the formula I, R₁The same or different alkylene groups having 2 to 4 carbon atoms.

5. The junction body according to claim 1, wherein: in the terminal structure represented by the formula I, R₂Is an alkyl group having 1 to 20 carbon atoms.

6. The junction body according to claim 1, wherein: in the terminal structure represented by the formula I, R₂Is methyl.

7. The junction body according to claim 1, wherein: in the terminal structure represented by the above formula I, -X-is-NH-.

8. The junction body according to claim 1, wherein: the content of the terminal structure represented by the formula I in the terminal-modified polyamide resin is 0.1 to 15 wt% based on the total weight of the terminal-modified polyamide resin.

9. The junction body according to claim 1, wherein: the content of the terminal structure represented by the formula I in the terminal-modified polyamide resin is 0.1 to 10 wt% based on the total weight of the terminal-modified polyamide resin.

10. The junction body according to claim 1, wherein: the thermoplastic resin composition has a tensile shear strength of not less than 10MPa as measured at a tensile speed of 5mm/min according to a joint test specimen specified in ISO 19095.

11. The junction body according to claim 1, wherein: the joined body is obtained by directly joining a thermoplastic resin composition and a metal.

12. The junction body according to claim 1, wherein: the terminal modified polyamide resin with the terminal structure shown in the formula I is prepared into a polyamide resin solution with the concentration of 0.01g/ml by using 96 wt% sulfuric acid as a solvent, and the relative viscosity eta r measured at 25 ℃ is 1.1-5.0.

13. The junction body according to claim 1, wherein: the weight average molecular weight Mw of the terminal modified polyamide resin with the terminal structure shown in the formula I is 10,000-400,000 measured by gel permeation chromatography.

14. The junction body according to claim 1, wherein: the melting point of the terminal-modified polyamide resin having a terminal structure represented by formula I is 215 ℃ or higher.

15. The junction body according to claim 1, wherein: the thermoplastic resin composition also comprises a filler, and the content of the filler is 5-80 wt% of the total weight of the thermoplastic resin composition.

16. A method for manufacturing the joined body according to any one of claims 1 to 15, characterized in that: the joined body is formed by injection molding of a thermoplastic resin composition heated and melted with a metal previously placed in a mold.

17. The manufacturing method according to claim 16, characterized in that: in the injection molding process of the conjugant, the temperature of a mould is between 60 and 180 ℃.

18. A method for manufacturing the joined body according to any one of claims 1 to 15, characterized in that: the joined body is obtained by welding a molded article of the thermoplastic resin composition and a metal by laser irradiation.