WO2024041951A1

WO2024041951A1 - Polyamide composition and article produced from the composition

Info

Publication number: WO2024041951A1
Application number: PCT/EP2023/072574
Authority: WO
Inventors: Rui DOU; Zhi Qiang Liu; Bangaru Dharmapuri Sriramulu Sampath; Xi Lin
Original assignee: Basf Se; Basf (China) Company Limited
Priority date: 2022-08-23
Filing date: 2023-08-16
Publication date: 2024-02-29

Abstract

The present invention relates to polyamide composition, which comprises a polyamide as component (A), a polyketone as component (B), a mixture of metal halides as component (C), a reinforcing agent as component (D), optionally, a nigrosine dye as component (E), and optionally, an antioxidant as component (F), wherein the component (A) is present in an amount of from 51% to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio of the component (A) to the component (B) in the range of from 3.5 : 1 or greater, and to an article obtained or obtainable from the polyamide composition.

Description

POLYAMIDE COMPOSITION AND ARTICLE PRODUCED FROM THE COMPOSITION

FIELD OF THE INVENTION

The present invention relates to a polyamide composition comprising a polyamide component and a polyketone component, and an article produced from the same.

BACKGROUND OF THE INVENTION

Various polymer blends have been developed and commercialized either for synergistic performance or for cost-performance balance. In recent years, there is an increasing interest in blends of polyamide (PA) and polyketone (POK) due to their compatibility with each other and the complementary properties thereof. The blends of PA and POK may combine advantages of both polymers and thus allow to provide materials with balanced mechanical properties, good chemical resistance and low moisture absorption.

Polyamide (also referred to as nylon) is a kind of polymer containing repeating amido moieties (- CONH-) in main chains, which has already been widely used as a base resin for engineering plastic for years in various industries such as automotive and appliance due to its good processibility, mechanical properties and low cost. Polyamide materials having various structural units are known, among which polyamide 6 (polycaprolactam, also referred to as PA6 or nylon 6) and polyamide 66 (poly(hexamethylene adipamide), also referred to as nylon 66) are most common for textile and plastic industries for their outstanding performances and cost ratios. Especially, polyamide materials are widely used in automotive applications. On average, more than 6kg of polyamide materials would be used per one car. Many of the automotive applications, such as power train components which generate and deliver power to the wheels, require polyamide materials to exhibit good mechanical performance, high heat resistance and dimension stability.

Polyketone, a relatively new type of thermoplastic copolymers of carbon monoxide and olefins, could help to remedy shortcomings of polyamide materials in the dimension stability and some mechanical properties such as tensile stiffness and Izod impact strength, which broadens the field of application of polyamide materials.

Various blends of polyamide with polyketone have been developed to combine their complimentary properties and broaden application fields of both materials.

For example, CN 107974076A discloses a flame retardant PA6/POK alloy material comprising 50 to 90 parts by weight of a nylon resin, 10 to 50 parts by weight of a polyketone resin, 10 to 20 parts by weight of a flame retardant, 4 to 8 parts by weight of a flame retardant synergist, 3 to 6 parts by weight of a compatilizer, 20 to 35 parts by weight of chopped fiber, 0.35 to 0.65 parts by weight of an antioxidant, 0.4 to 0.7 parts by weight of a lubricant. It was described in the patent application that the alloy material could provide molding parts having improved properties such as water absorption, dimension stability and mechanical property compared with PA6.

CN106832902A discloses a PA/POK alloy material comprising 55 to 85% of PA, 10 to 40% of POK, 0 to 10% of a compatilizer, 0 to 3% of an antiwear agent, 0.3 to 1 % of a lubricant, 0.3 to 1% of a composite thermal stabilizer. It was described in the patent application that the alloy material could provide molding parts having high abrasion resistance.

US10336903B2 discloses a polyamide composition consisting of at least one polyamide, at least one polyketone in an amount of 1 to 4 wt% based on the total weight of the composition, at least one rubber in an amount of 10 to 35 wt% based on the total weight of the composition, and optionally one or more further components selected from the group consisting of fibrous fillers, particulate fillers, heat stabilizers, anti-oxidants, plasticizers, lubricants, colorants, pigments, antistatic agents, flame-retardant agents, nucleating agents, and catalysts. It was described in the patent application that the polyamide materials exhibit improved certain chemical resistances and mechanical properties.

Those PA/POK blends as described in those patent applications may provide more or less improved processing performances or mechanical properties compared with conventional polyamide materials. However, such PA/POK blends still have drawbacks such as inferior longterm heat-aging performance, which is a key performance for engineering plastic applications in industries like automotive and appliance.

Further, the PA/POK blends as described in those patent applications may have insufficient heat resistance since it was known that polyketone materials generally exhibit a deterioration of physical properties upon thermal oxidative degradation which is typically autocatalytic under heat in the presence of oxygen. For example, EP0714938A discloses using a combination of a primary antioxidant selected from hindered phenols, aromatic amines and mixtures thereof, a secondary antioxidant selected from phosphites, phosponites and mixtures thereof, and a scavenger to improve heat resistance of polyketone materials. It was described in the patent application that the thermal oxidative stability of polyketone materials may be improved by certain antioxidants, but the addition of secondary antioxidants such as phosphites or phosphonites has little or no stabilization effect.

There is need to provide a PA/POK blend having improved mechanical properties and also a good long-term heat resistance. It will be desirable if PA/PK blends with synergistic toughness, good tensile strength and excellent long-term heat-aging performance could be provided.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a polyamide material having improved mechanical properties, preferably a polyamide material having improved mechanical properties and also a good long-term heat resistance. Accordingly, the present invention provides a polyamide composition, which comprises

- a polyamide as component (A),

- a polyketone as component (B),

- a mixture of metal halides as component (C),

- a reinforcing agent as component (D),

- optionally, a nigrosine dye as component (E), and

- optionally, an antioxidant as component (F), wherein the component (A) is present in an amount of from 51% to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio of 3.5 : 1 or greater.

The present invention also provides an article produced from the polyamide composition as described herein.

It has been surprisingly found that the polyamide composition according to the present invention could provide good mechanical properties in terms of toughness, especially significantly improved toughness against high humidity conditions. It has also been found that certain polyamide composition according to the present invention could provide excellent long-term heat resistance.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described in detail hereinafter. It is to be understood that the present invention can be embodied in many different ways and shall not be construed as limited to the embodiments set forth herein.

The singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. The terms “comprise”, “comprising”, etc. are used interchangeably with “contain”, “containing”, etc. and are to be interpreted in a non-limiting, open manner. That is, e.g., further components or elements can be present. The expressions “consists of’ or “consisting of” or cognates can be embraced within “comprises” or “comprising” or cognates.

As used herein, the term “structural unit(s)” is intended to refer to the minimal molecular residue(s) resulting from respective monomer molecules after polymerization. For example, PA6 has a type of structural unit of -NH(CH₂)5CO-, PA66 has two types of structural units, i.e., - NH(CH₂)SNH- and -CO(CH₂)4CO-, and so on.

As used herein, the term “repeating unit(s)” is intended to refer to the minimal unit(s) with same chemical composition in a polymer. The repeating units can consist of one or more types of structural units. For example, PA6 has repeating units same as the structural units, i.e., - NH(CH₂)5CO-; PA66 has repeating units of -NH(CH₂)6NHCO(CH₂)4CO- which consist of two types of structural units, i.e., -NH(CH₂)eNH- and -CO(CH₂)4CO-. Component (A)

Polyamide, as well known in the art, refers to a polymer that contains repeating amide groups (- CONH-) in the main chain of the polymers. Generally, a polyamide is made up of many identical repeating units linked by covalent bonds.

Useful polyamide may be typically derived from a monomer selected from the group consisting of lactams, amino acids, a combination of dicarboxylic acid and diamine, and a combination of dicarboxylic acid chloride and diamine.

Such polyamide as component (A) in the polyamide composition according to the present invention may have repeating units of formula (I):

O

- [-NH- R¹- C-P _(|)j in which

R¹ is a hydrocarbylene group having from 3 to 29 carbon atoms, preferably from 5 to 17 carbon atoms, more preferably from 5 to 11 carbon atoms.

Particularly, R¹ in formula (I) is an alkylene or cycloalkylene group, more preferably an alkylene group, having a number of carbon atoms as described herein.

The polyamide having repeating units of formula (I) is typically derived from at least one aliphatic monomer selected from the group consisting of (1) lactams having from 4 to 30 carbon atoms and (2) amino acids having from 4 to 30 carbon atoms.

Suitable lactams preferably have from 6 to 18 carbon atoms, more preferably from 6 to 12 carbon atoms. Examples of the lactams may include, but are not limited to, caprolactam, caprylolactam, caprinolactam, undecanolactam, laurolactam, or any combinations thereof.

Suitable amino acids preferably have from 6 to 18 carbon atoms, more preferably from 6 to 12 carbon atoms. Examples of the amino acids may include, but are not limited to, 2-aminoadipic acid, 9-aminononanoic acid, 10-aminodecanoic acid, 11-aminoundecanoic acid, 12- aminododecanoic acid, or any combinations thereof.

Alternatively, the polyamide as component (A) in the polyamide composition according to the present invention may have repeating units of formula (II):

O O r _? n , H 1 -|-NH-R²-NH— C— R³-C-|- i) in which

R² is a hydrocarbylene group having from 4 to 24 carbon atoms, preferably from 4 to 18, and R³ is a hydrocarbylene group having from 4 to 30 carbon atoms, preferably from 4 to 20. Particularly, R² in formula (II) is an alkylene or cycloalkylene group, preferably an alkylene group, having a number of carbon atoms as described herein. Alternatively or additionally, R³ in formula (II) is an alkylene, cycloalkylene or arylene group, preferably an alkylene or arylene group, having a number of carbon atoms are described herein.

The polyamide having repeating units of formula (II) is typically derived from monomers which are selected from the group consisting of (1) a combination of dicarboxylic acids having from 6 to 32 carbon atoms and diamines having from 4 to 24 carbon atoms and (2) a combination of dicarboxylic acid chlorides having from 6 to 32 carbon atoms and diamines having from 4 to 24 carbon atoms.

Suitable aliphatic diamines preferably have from 4 to 24 carbon atoms, more preferably from 4 to 18 carbon atoms, for example 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13 or 14 carbon atoms. The aliphatic diamines may be linear or branched aliphatic diamines. Examples of the aliphatic diamines may include, but are not limited to, 1 ,4-butanediamine, 1,5-pentanediamine, 1 ,6- hexanediamine, 1 ,7-heptanediamine, 1,8-octanediamine, 1 ,9-nonanediamine, 1 ,10- decanediamine, 1 ,11-undecanediamine, 1 ,12-dodecanediamine, 1 ,13-tridecanediamine, 1,14- tetradecanediamine, 1 ,16-hexadecanediamine, 1,18-octadecanediamine, 1 ,20-eicosanediamine, 1 ,22-docosanediamine, 2-methylpentane-1 ,5-diamine, 3-methylpentane-1 ,5-diamine, 2,5- dimethylhexane-1 ,6-diamine, 2,4-dimethylhexane-1 ,6-diamine, 3,3-dimethylhexane-1 ,6-diamine,

2.2-dimethylhexane-1 ,6-diamine, 2,2,4-trimethylhexane-1 ,6-diamine, 2,4,4-trimethylhexane-1 ,6- diamine, 2,3-dimethylheptane-1,7-diamine, 2,4-dimethylheptane-1,7-diamine, 2,5- dimethylheptane-1 ,7-diamine, 2,2-dimethylheptane-1,7-diamine, 2-methyloctane-1 ,8-diamine,

1.3-dimethyloctane-1 ,8-diamine, 1 ,4-dimethyloctane-1 ,8-diamine, 2,4-dimethyloctane-1 ,8- diamine, 3,4-dimethyloctane-1 ,8-diamine, 4,5-dimethyloctane-1,8-diamine, 2,2-dimethyloctane- 1 ,8-diamine, 3,3-dimethyloctane-1 ,8-diamine, 4,4-dimethyloctane-1 ,8-diamine, 2,4- diethylhexane-1,6-diamine, 5-methylnonane-1,9-diamine, and any combinations thereof.

Suitable dicarboxylic acids may be aliphatic or aromatic and have from 6 to 32, preferably 6 to 22 carbon atoms, for example 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Examples of the dicarboxylic acids may include, but are not limited to, adipic acid, pimelic acid, sebacic acid, undecanedioic acid, dodecandioic acid, tridecanedioic acid, tetradecandioic acid, pentadecandioic acid, hexadecanedioic acid, octadecandioic acid, terephthalic acid, isophthalic acid, and any combinations thereof.

Suitable dicarboxylic acid chlorides may be aliphatic or aromatic and have from 6 to 32, preferably 6 to 22 carbon atoms, for example 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17,18, 19 or 20 carbon atoms. Examples of the dicarboxylic acid chlorides may include, but are not limited to, adipoyl dichloride, heptanedioyl dichloride, azelaoyl dichloride, sebacoyl dichloride, undecanedioyl dichloride, lauroyl dichloride and any combinations thereof.

For example, the polyamide as component (A) may be at least one selected from the group consisting of PA6, PA7, PA8, PA9, PA11 , PA12, PA410, PA510, PA513, PA515, PA66, PA69, PA610, PA612, PA613, PA614, PA618, PA636, PA88, PA810, PA812, PA1010, PA1012, PA1014, PA1018, PA1210, PA1212, PA1214, PA1218, PA1313, PA1410, PA1412, PA1414, PA1418, PA4T, PA9T, PA10T, PA11T and any combinations thereof.

Useful polyamide may also be a blend of polyamides as described above or a copolymerized polyamide (co-polyamide). There is no limitation to the type of the co-polyamide, which may be for example a block copolymer, a random copolymer, a graft copolymer or an alternating copolymer. Examples of the co-polyamide may include, but are not limited to, PA6/PA510, PA6/PA610, PA6/PA612, PA6/PA1010, PA66/PA410, PA66/PA510, PA66/PA610, PA66/PA612, PA66/PA1010, PA6/6T (mole ratio of 6 to 6T from 1 :99 to 99:1), PA66/6T (mole ratio of 66 to 6T from 1 :99 to 99:1), PA6T/6I (mole ratio of 6T:6I from 99:1 to 65:35).

In some embodiments according to the present invention, the polyamide having the repeating units of formula (I) as described herein is particularly useful as component (A) in the polyamide composition. The polyamide having the repeating units of formula (I) in which R¹ having 5 to 11 carbon atoms is more preferably useful as component (A) in the polyamide composition, among which PA6 is most preferable.

The polyamide as component (A) in the polyamide composition according to the present invention may have any suitable molecular weights without being limited. Preferably, the relative viscosity of the polyamide is from 1.8 to 4.0, as measured in 96 % by weight sulfuric acid at 25°C.

The component (A) may be present in the polyamide composition according to the present invention in an amount of from 51% to 68% by weight, for example from 53% to 67% by weight, based on the total weight of the polyamide composition.

The polyamide disclosed herein should not be limited to the ones prepared from virgin crude oil monomers, and could be completely or at least partially biobased or derived from waste stream or recycling activities, i.e., the polyamide used in the present application can be based on renewable materials, secondary raw materials or recycled raw materials. For example, PA6, PA9, PA66, PA9T, PA10T and PA11T used as component (A) in the present application could be prepared or obtained or derived from monomers that obtained in a re-monomerisation processes.

Component (B)

Polyketone generally refers to a class of polymers which are derived from carbon monoxide and an olefinically unsaturated monomer. Useful polyketone as component (B) in the polyamide composition according to the present invention may have at least one type of repeating units of formula (III):

in which R⁴, R⁴’, R⁵ and R⁵’ are each independently hydrogen or hydrocarbyl group having from 1 to 40 carbon atoms, preferably from 1 to 20 carbon atoms, more preferably from 1 to 10 carbon atoms, most preferably from 1 to 5 carbon atoms.

The polyketone as component (B) may have one or more types of the repeating units of formula (III) as described herein. For example, the polyketone as component (B) may have at least two types of the repeating units of formula (III).

Suitable olefinically unsaturated monomers may include for example alpha-olefins having from 2 to 10 carbon atoms and substituted derivatives thereof, and monocyclic or polycyclic aromatic monomers having from 6 to 30 carbon atoms and alkyl substituted derivatives thereof. Particularly, the olefinically unsaturated monomers are selected from alpha-olefins having from 2 to 8 carbon atoms, such as ethene, propene, butene, isobutene and pentene. It is preferred that the olefinically unsaturated monomers are ethene or a mixture of ethene and an additional alpha-olefin having from 3 to 6 carbon atoms, especially propene or butene. It is further preferred that the molar ratio of ethene to the additional alpha-olefin having from 3 to 6 carbon atoms is greater than or equal to 1 , for example, in the range of 2 to 30.

In some embodiments according to the present invention, the polyketone as component (B) in the polyamide composition according to the present invention may be a copolymer of ethene/CO, propene/CO, ethene/propene/CO or butene/CO, wherein CO represents carbon monoxide.

The polyketone as component (B) may have a number average molecular weight (Mn) in the range of from 10,000 to 300,000, for example from 15,000 to 200,000, or from 15,000 to 90,000. Additionally or alternatively, the polyketone as component (B) may have a weight average molecular weight (Mw) in the range of from 25,000 to 1 ,000,000, for example from 50,000 to 600,000, or from 80,000 to 300,000. The polyketone as component (B) preferably has a polydispersity index in the range of from 1.5 to 4.0, for example from 2.0 to 3.5.

In some embodiments according to the present invention, the polyketone as component (B) preferably has a number average molecular weight in the range of from 30,000 to 90,000, particularly from 50,000 to 90,000.

The polyketone as component (B) may have a melt flow rate of from 2 to 300 g/10min, for example, from 2 to 4 g/10min, from 4 to 8 g/10min, from 50 to 70 g/10min, or from 200 to 300 g/10min.

The polyketone as component (B) may have an intrinsic viscosity (IV) of from 0.8 to 2.5 dL/g, for example from 0.8 to 1.2 dL/g, from 1.2 to 1.7 dl_/g, or from 1.7 to 2.5 dL/g, as measured in a capillary viscometer using hexafluoroisopropyl alcohol at 25°C as the solvent.

For the purpose of the present invention, the polyketone may be those prepared via known processes or be commercially available polyketone materials. Examples of commercially available polyketone materials include, but are not limited to, POKETONE series from Hyosung Co. Ltd, such as POKETONE™ M630, POKETONE™ M410, POKETONE™ M330, and POKETONE™ M930.

The component (B) may be present in the polyamide composition according to the present invention in an amount of from 0.1% to 20% by weight, from 0.2% to 20% by weight, or from 0.3% to 15% by weight, based on the total weight of the polyamide composition.

The component (A) and the component (B) are present in the polyamide composition according to the present invention at a weight ratio (A : B) of 3.5 : 1 or greater, for example in the range of from 3.5 : 1 to 200 : 1. Preferably, the weight ratio of the component (A) to the component (B) is in the range of from 4 : 1 to 150 : 1, preferably in the range of from 5 : 1 to 100 : 1.

Component (C)

The polyamide composition according to the present invention comprises a mixture of metal halides as component (C). The mixture of metal halides may comprise or consist of a copper monohalide and an alkali metal halide, for example chloride, bromide and iodide. Particularly, the copper monohalide may be selected from cuprous iodide and cuprous bromide. The alkali metal halide may be selected from iodides and bromides of lithium, sodium and potassium. Preferably, the polyamide composition according to the present invention comprises a mixture of cuprous iodide and potassium iodide as component (C).

The mixture of metal halides may comprise the copper monohalide (Cu) and the alkali metal halide (AM) at a molar ratio (Cu : AM) in the range of from 1 : 2 to 1 : 20, preferably from 1 : 2 to 1 : 6.

The component (C) may be present in the polyamide composition according to the present invention in an amount of from 0.1% to 3.0% by weight, or from 0.5% to 2.5% by weight, based on the total weight of the polyamide composition.

Component (D)

Useful reinforcing agents as component (D) may be of various types without particular restrictions, such as fibers, whiskers, flakes and particles, but may be preferably selected from fibrous reinforcing agents and particulate fillers.

Examples of the fibrous reinforcing agents may include, but are not limited to glass fibers, carbon fibers, boron fibers, asbestos fibers, polyvinyl alcohol fibers, polyester fibers, acrylic fibers, wholly aromatic polyamide fibers, polybenzoxazole fibers, polytetrafluoroethylene fibers, kenaf fibers, bamboo fibers, hemp fibers, bagasse fibers, high strength polyethylene fibers, alumina fibers, silicon carbide fibers, potassium titanate fibers, brass fibers, stainless steel fibers, steel fibers, ceramic fibers, wollastonite fibers, and basalt fibers, among which glass fibers and carbon fibers are particularly preferred. There is no particular restriction to the fiber length and the fiber diameter of the fibrous reinforcing agents. For example, chopped fibers having a length in the range of from 1 to 10 mm, preferably from 2 to 6 mm, or continuous fibers may be used as starting material of the reinforcing agent. The fibers will be broken down during processing, for example kneading the polyamide composition, to a length of a few hundreds of microns as present in the obtained moldings. The fiber diameter is preferably from 3 to 20 pm, more preferably from 7 to 13 pm.

Examples of the cross-sectional shape of the fibrous reinforcing agents include for example circle, rectangle, ellipse, and other non-circular cross sections, among which circle shape is especially preferred. The fibrous reinforcing agents may have a cross section with an aspect ratio in the range of from 2:1 to 5:1.

The glass fibers may have been surface-treated by a silane coupling agent, which is for example selected from vinylsilane-based coupling agents, acrylic silane-based coupling agents, epoxysilane-based coupling agents and aminosilane-based coupling agents, preferably aminosilane-based coupling agents. The silane coupling agent may be dispersed in a sizing agent. Examples of the sizing agent may include, but are not limited to acrylic compounds, acrylic/maleic derivative modified compounds, epoxy compounds, urethane compounds, urethane/maleic derivative modified compounds and urethane/amine modified compounds.

Particulate fillers may be organic or inorganic, and have a variety of particle sizes, ranging from particles in dust form to coarse particles. Examples of materials that may be used as inorganic particulate fillers include, but are not limited to kaolin, chalk, wollastonite, talc, calcium carbonate, silicates, titanium dioxide, zinc oxide, graphite, mica, vermiculite, montmorillonite, and glass particles (e.g., glass beads).

In some embodiments according to the present invention, the reinforcing agent as component (D) is selected from glass fibers. The glass fibers may be for example E-glass fibers, A-glass fibers, D-glass fibers, AR-glass fibers, C-glass fibers and S-glass fibers.

The component (D) is present in the polyamide composition according to the present invention in an amount of from 10% to 50% by weight, from 10 % to 40% by weight, or from 20% to 40% by weight based on the total weight of the polyamide composition.

The reinforcing agents as component (D) disclosed herein can also be based on renewable materials, secondary raw materials or recycled raw materials. For example, the glass fibers used herein can be recycled glass fibers, or renewable glass fibers obtained from conventional recycling treatment process.

Component (E)

The polyamide composition according to the present invention optionally, but preferably comprises a nigrosine dye as component (E). The nigrosine dye is a class of synthetic black dyes prepared from a mixture of nitrobenzene, aniline, aniline hydrochloride, etc. in the presence of a catalyst, e.g., copper-iron catalyst or iron chloride. The nigrosine dye is known useful for coloring various materials such as inks, waxes, plastics and lacquers and as wood stains, and has been used as a coloring agent in a polyamide material.

Surprisingly, it has been found that the nigrosine dye, when comprised in the polyamide composition according to the present invention, can contribute to the heat resistance of the polyamide composition according to the present invention.

Therefore, it is preferred that the polyamide composition according to the present invention comprises a nigrosine dye as component (E).

There is no particular restriction to the type of the nigrosine dye useful in the polyamide composition according to the present invention, which may be water-soluble, ethanol-soluble or fat-soluble. Such a nigrosine is commercially available, for example under the trade name NUBIAN® BLACK series from Orient Chemical Industry Co., Ltd. The nigrosine may also be available as a masterbatch, for example under the trade name of Ultrabatch® 434 from BASF.

The component (E) may be present in the polyamide composition according to the present invention in an amount of from 0.01 % to 5% by weight, from 0.02% to 2% by weight, or from 0.02% to 1% by weight, based on the total weight of the polyamide composition.

Component (F)

The polyamide composition according to the present invention optionally, but preferably comprises an antioxidant as component (F).

The antioxidant is preferably selected from hindered phenol-based antioxidants, phosphite- based antioxidants, aromatic amine-based antioxidants, and any combinations thereof. More preferably, the antioxidant is selected from hindered phenol-based antioxidants, phosphite- based antioxidants, or any combinations thereof, preferably a combination of a hindered phenol- based antioxidant and a phosphite-based antioxidant.

Useful hindered phenol-based antioxidants as component (F) in the polyamide composition according to the present invention may be selected from the group consisting of N,N’-hexane- 1,6-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide) (d1) (BASF lrganox®1098), 4,6- bis(octylthiomethyl)-o-cresol (d2) (BASF Irganox® 1520), octyl-3,5-di-tert-butyl-4- hydroxyhydrocinnamate (d3), 3,5-bis(1 ,1-dimethylethyl)-4-hydroxybenzenepropanoic acid C7- C9-branched alkyl ester (d4, n=7-9), 2,4-bis[(dodecylthio)methyl]-o-cresol (d5) (BASF Irganox® 1726), pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) (d6) (BASF lrganox®1010), triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4- hydroxyphenyl) propionate] (d7) (BASF lrganox®245), 2,4-bis(n-octylthio)-6-(4-hydroxy-3,5-di- tert-butylanilino)-1 ,3,5-triazine (d8) (BASF Irganox® 565), tris-(3,5-di-tert-butyl-4- hydroxybenzyl)isocyanurate (d9) (BASF lrganox®3114), 2,2-thiodiethylene bis[3-(3,5-di-tert- butyl-4-hydroxyphenyl)propionate] (d10) (BASF lrganox®1035), 4,4’-butylidene bis-(3-methyl-6- tert-butylphenol) (dl l), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (d12) (BASF Irganox® 1076), 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene (d13) (BASF lrganox®1330), hexamethylene bis[3-3,5-di-tert-butyl-4-hydroxyphenyl]propionate](d14) (BASF lrganox®259) and calcium bis[monoethyl(3,5-di-tert-butyl-4-hydroxybenzyl)phosphonate] (d15) (BASF Irganox® 1425), more preferably N,N’-hexane-1 ,6-diyl bis(3-(3,5-di-tert-butyl-4- hyd roxypheny I) propionam ide) (d 1 ) .

Useful phosphite-based antioxidants as component (F) in the polyamide composition according to the present invention may be selected from the group consisting of diphenyl mono(2- ethylhexyl) phosphite (d16), diphenyl monotridecyl phosphite (d17), diphenyl isodecyl phosphite (d18), diphenyl isooctylphosphite (d19), diphenyl nonylphenyl phosphite (d20), triphenyl phosphite (d21), triisodecyl phosphite (d22), tris(2,4-di-tert-butylphenyl)phosphite (d23), tris(2- ethylhexyl)phosphite (d24), tetraphenyl dipropylene glycol diphosphate (d25), distearyl pentaerythritol diphosphite (d26), 2,2’-ethylidene bis(4,6-di-tert-butyl-phenol)fluorophosphate (d27), 4,4’-isopropylidene-diphenyl alkyl (C12 to Cis) phosphites (d28 (n=12-15), tristearyl phosphite (d29), bis(nonylphenyl)pentaerythritol diphosphate (d30), bis(tridecyl) pentaerythritol diphosphate (d31), hydrogenated bisphenol A-pentaerythritol phosphite polymers (d32), 4,4’- butylidene bis(3-methyl-6-tert-butylphenyl-di-tridecyl phosphite) (d33), tris(nonyl- phenyl)phosphite (d34) and tris(methylphenyl) phosphite (d35), more preferably tris(2,4-di-tert- butylphenyl)phosphite (d25).

In some embodiments according to the present invention, a combination of a hindered phenol- based antioxidant and a phosphite-based antioxidant is used as component (F) in the polyamide composition. The combination of the hindered phenol-based antioxidant and the phosphite-based antioxidant can endow the polyamide composition better heat resistance compared with using a single antioxidant. Preferably, a combination of N,N’-hexane-1,6-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionamide) and tris(2,4-di-tert-butylphenyl) phosphite is used as component (F) in the polyamide composition according to the present invention.

The hindered phenol-based antioxidant and the phosphite-based antioxidant, when used in combination, may be present at a weight ratio in the range of from 10 : 1 to 1 : 10, from 7 : 1 to 1 : 5, or from 5 : 1 to 1 : 1.

The component (F) may be present in the polyamide composition according to the present invention in an amount of from 0.01% to 5% by weight, or from 0.02% to 2% by weight, based on the total weight of the polyamide composition.

Other Components

The polyamide composition according to the present invention may optionally comprise at least one further additive, for example, lubricants, colorants other than nigrosine such as dyes and/or pigments, flame-retardant agents, release agents, impact modifiers, compatibilizing agents, thermostabilizers, photostabilizers such as UV stabilizers, plasticizers, surfactants, nucleating agents, coupling agents, antimicrobial agents, antistatic agents, and any combinations thereof.

The at least one further additive, when present, may be used in conventional amounts. For example, the polyamide composition may comprise the at least one further additive in an amount of from 0.01% to 15% by weight, based on the total weight of the polyamide composition.

The polyamide composition may for example comprise a lubricant. Suitable lubricant is preferably selected from esters or amides of saturated or unsaturated aliphatic carboxylic acids having from 10 to 40, preferably from 16 to 22 carbon atoms with saturated aliphatic alcohols or amines which comprise from 2 to 40, preferably from 2 to 6 carbon atoms.

The carboxylic acids may be mono- or dibasic, for example pelargonic acid, palmitic acid, lauric acid, margaric acid, dodecanedioic acid and behenic acid, particularly stearic acid, capric acid, and also montanic acid (a mixture of fatty acids having from 30 to 40 carbon atoms).

The aliphatic alcohols may be mono- to tetrahydric, for example n-butanol, n-octanol, stearyl alcohol, ethylene glycol, propylene glycol, neopentyl glycol and pentaerythritol, preferably glycerol and pentaerythritol. The aliphatic amines may be mono- to trifunctional, for example stearylamine, ethylenediamine, propylenediamine, hexamethylenediamine and di(6-aminohexyl) amine, preferably ethylenediamine and hexamethylenediamine.

Preferable esters or amides are N,N’-ethylene di(stearamide), glycerol distearate, glycerol tristearate, glycerol monopalmitate, glycerol trilaurate, glycerol monobehenate and pentaerythritol tetrastearate, among which N,N’-ethylene di(stearamide) is particularly preferred as a lubricant in the polyamide composition according to the present invention.

Other lubricants may be long-chain fatty acids (e.g., stearic acid or behenic acid), salts thereof (e.g., Ca stearate or Zn stearate), or montan waxes (mixtures of straight-chain, saturated carboxylic acids having chain lengths of from 28 to 32 carbon atoms), Ca montanate or Na montanate, and also low-molecular-weight polyethylene waxes and low-molecular-weight polypropylene waxes.

The lubricant, if comprised, may be present in an amount of from 0.01% to 2 % by weight, or from 0.2% to 1 % by weight, based on the total weight of the polyamide composition.

The polyamide composition according to the present invention may also comprise a colorant other than nigrosine, which can be inorganic pigments (e.g., TiC>2, SnC>2, ZnO, ZnS, SiC>2, etc.) and organic pigments, and also dyes. Suitable colorants are known and described for example in EP 1722984 B1 , EP 1353986 B1 , or DE 10054859 A1.

The colorant, if comprised, may be present in an amount of from 0.01% to 15% by weight, or from 1% to 15% by weight, or from 2% to 8% by weight, based on the total weight of the polyamide composition.

<lmpact Modifier

The polyamide composition according to the present invention may also for example comprise an impact modifier. Suitable impact modifiers may include polyolefin-based, styrene-based, unsaturated carboxylic acid-based impact modifiers, and also those modified by a functional block, such as epoxy functional block and/or acid anhydride block. The epoxy function block may be units derived from a glycidyl (meth)acrylate. The acid anhydride block may be units derived from maleic anhydride.

Suitable polyolefin-based impact modifiers may include polyolefins comprising repeating units derived from olefin having from 2 to 10 carbon atoms. Examples of such olefins include ethene, 1-butene, 1-propene, 1-pentene, 1-octene and a mixture of ethene and 1-octene, preferably ethene, 1-propene and a mixture of ethene and 1-octene. Suitable unsaturated carboxylic acid-based impact modifiers may include blocks derived from carboxylic acid and derivates thereof such as ester, imide and amide. Suitable carboxylic acids and derivates thereof are for example acrylic acid, acrylic acid, methacrylic acid, maleic acid, fumaric acid, glutaconic acid, itaconic acid, citraconic acid, (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (methyl)acrylate and isobutyl (meth)acrylate.

The impact modifier may also be a bi- or ter-polymer or a core-shell structure polymer. Examples of such impact modifiers include styrene/ethene/butene copolymer (SEBS), ethenemethyl acrylate-glycidyl methacrylate terpolymer, ethene/propene/diene rubber (EPDM) and ethene-octene copolymer.

The impact modifier, if comprised, may be present in an amount of from 0.01% to 15% by weight, or from 1 to 15% by weight, or from 5 to 10% by weight, based on the total weight of the polyamide composition.

The polyamide composition according to the present invention may also for example comprise a plasticizer, including but are not limited to dioctyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, hydrocarbon oils and N-(n-butyl) benzenesulfonamide.

The plasticizer, if comprised, may be present in an amount of from 0.01% to 15% by weight, or from 1% to 15% by weight, or from 5% to 10% by weight, based on the total weight of the polyamide composition.

In some embodiments, the polyamide composition according to the present invention does not comprise a polyol or polyol ether, for example glycerol, dipentaerythritol, triipentaerythritol, trimethylolethane, trimethylolpropane, di(trimethylolpropane), trimethylolpropane triglycidyl ether, D-mannitol, D-sorbitol, xylitol and arabitol.

Formulations

In some exemplary embodiments, the polyamide composition according to the present invention comprises

- a polyamide as component (A), which has repeating units of formula (I): o

- [-NH- R¹- C-F _(|) in which

R¹ is a hydrocarbylene group having from 5 to 17 carbon atoms, more preferably from 5 to 11 carbon atoms,

- a polyketone as component (B),

- a mixture of a copper monohalide and an alkali metal halide as component (C),

- a reinforcing agent selected from glass fibers as component (D), - optionally, a nigrosine dye as component (E), and

- optionally, an antioxidant as component (F), wherein the component (A) is present in an amount of from 51% to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio in the range of from 3.5 : 1 to 200 : 1.

In some other exemplary embodiments, the polyamide composition according to the present invention comprises

- a polyamide as component (A), which has repeating units of formula (I):

in which

- a polyketone as component (B),

- a mixture of a copper monohalide and an alkali metal halide as component (C),

- a reinforcing agent selected from glass fibers as component (D),

- a nigrosine dye as component (E), and

In some further exemplary embodiments, the polyamide composition according to the present invention comprises

- a polyamide as component (A), which has repeating units of formula (I):

O

-+NH-R¹-C - _(|)J in which

- a polyketone as component (B),

- a mixture of a copper monohalide and an alkali metal halide as component (C),

- a reinforcing agent selected from glass fibers as component (D),

- a nigrosine dye as component (E), and

- an antioxidant as component (F), wherein the component (A) is present in an amount of from 51% to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio in the range of 3.5 : 1 to 200 : 1.

In any of the above exemplary embodiments, the weight ratio of the component (A) to the component (B) is in the range of from 4 : 1 to 150 : 1 , preferably in the range of from 5 : 1 to 100 : 1.

In any of the above exemplary embodiments, a mixture of cuprous iodide and potassium iodide is comprised as component (C).

In any of the above exemplary embodiments, the antioxidant is selected from hindered phenol- based antioxidants, phosphite-based antioxidants or any combinations thereof, particularly a combination of a hindered phenol-based antioxidant and a phosphite-based antioxidant, preferably a combination of N,N’-hexane-1 ,6-diyl bis(3-(3,5-di-tert-butyl-4- hydroxyphenyl) propionamide) and tris(2,4-di-tert-butylphenyl) phosphite.

In some particularly preferable embodiments, the polyamide composition according to the present invention comprises

- a polyamide as component (A), which has repeating units of formula (I):

in which

R¹ is a hydrocarbylene group having from 5 to 11 carbon atoms,

- a polyketone as component (B),

- a mixture of a copper monohalide and an alkali metal halide as component (C),

- a reinforcing agent selected from glass fibers as component (D),

- optionally a nigrosine dye as component (E), and

- optionally a combination of a hindered phenol-based antioxidant and a phosphite-based antioxidant as component (F), wherein the component (A) is present in an amount of from 51% to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio of 4 : 1 to 150 : 1.

In those particularly preferable embodiments, the polyamide composition according to the present invention comprises the component (E). Further, the polyamide composition according to the present invention comprise the component (E) and the component (F).

In those particularly preferable embodiments, the weight ratio of the component (A) to the component (B) is in the range of 5 : 1 to 100 : 1.

In those particularly preferable embodiments, the polyamide composition comprises no polyol, for example glycerol, dipentaerythritol, triipentaerythritol, trimethylolethane, trimethylolpropane, di(trimethylolpropane), trimethylolpropane triglycidyl ether, D-mannitol, D-sorbitol, xylitol and arabitol. Articles

The polyamide composition according to the present invention may be processed into various structures or forms by conventional methods. For example, individual components of the polyamide composition according to the present invention may be mixed and then molded, for example via injection and/or extrusion in a conventional apparatus such as a screw extruder, a Brabender mixer or a Banbury mixer to form articles. The mixing is generally carried out at a temperature sufficient to keep polymeric components as a molten medium in the range of from 220 °C to 260 °C.

It will be understood that all components of the polyamide composition may be mixed at the same time. Alternatively, some components of the polyamide composition may be pre-mixed and then mixed with other components. For example, non-polymeric components of composition may be added at any point during processing, in particular by hot or cold blending with the polymer matrix.

Accordingly, the present invention provides an article produced from the polyamide composition according to the present invention.

The polyamide composition according to the present invention has good mechanical properties, especially improved toughness, and may also have a good long-term heat resistance. Thus, the article produced from the polyamide composition according to the present invention can be used in many fields, including but being not limited to, automobile parts which has a requirement of long-term heat resistance over 120 °C. The automobile parts could be engine parts, chassis parts, crossbeam parts of any type, etc.

Embodiments

Various embodiments are listed below. It will be understood that the embodiments listed below can be combined with all aspects and other embodiments in accordance with the scope of the invention.

1. A polyamide composition, which comprises

- a polyamide as component (A),

- a polyketone as component (B),

- a mixture of metal halides as component (C),

- a reinforcing agent as component (D),

- optionally, a nigrosine dye as component (E), and

- optionally, an antioxidant as component (F), wherein the component (A) is present in an amount of from 51 % to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio of the component (A) to the component (B) in the range of from 3.5 : 1 or greater. 2. The polyamide composition according to Embodiment 1 , wherein the weight ratio of the component (A) to the component (B) is in the range of from 4 : 1 to 150 : 1.

3. The polyamide composition according to Embodiment 2, wherein the weight ratio of the component (A) to the component (B) is in the range of from 5 : 1 to 100 : 1.

4. The polyamide composition according to any of preceding Embodiments, wherein the mixture of metal halides comprises or consists of a copper monohalide and an alkali metal halide.

5. The polyamide composition according to Embodiment 4, wherein the mixture of metal halides is a mixture of cuprous iodide and potassium iodide.

6. The polyamide composition according to any of preceding Embodiments, wherein the component (C) is present in an amount of from 0.1 % to 3.0% by weight, based on the total weight of the polyamide composition.

7. The polyamide composition according to Embodiment 6, wherein the component (C) is present in an amount of from 0.5% to 2.5% by weight, based on the total weight of the polyamide composition.

8. The polyamide composition according to any of preceding Embodiments, wherein the reinforcing agent is selected from glass fibers.

9. The polyamide composition according to any of preceding Embodiments, wherein the component (D) is present in an amount of from 10% to 50% by weight, based on the total weight of the polyamide composition.

10. The polyamide composition according to Embodiment 9, wherein the component (D) is present in an amount of from 10 % to 40% by weight, based on the total weight of the polyamide composition.

11. The polyamide composition according to Embodiment 10, wherein the component (D) is present in an amount of from 20% to 40% by weight, based on the total weight of the polyamide composition.

12. The polyamide composition according to any of preceding Embodiments, wherein the component (E) is present in an amount of from 0.01% to 5% by weight, based on the total weight of the polyamide composition.

13. The polyamide composition according to Embodiment 12, wherein the component (E) is present in an amount of from 0.02% to 2% by weight, based on the total weight of the polyamide composition. 14. The polyamide composition according to Embodiment 13, wherein the component (E) is present in an amount of from 0.02% to 1% by weight, based on the total weight of the polyamide composition.

15. The polyamide composition according to any of preceding Embodiments, wherein the antioxidant is selected from hindered phenol-based antioxidants, phosphite-based antioxidants, aromatic amine-based antioxidants or any combinations thereof.

16. The polyamide composition according to Embodiment 15, wherein the antioxidant is selected from a combination of a hindered phenol-based antioxidant and a phosphite-based antioxidant.

17. The polyamide composition according to Embodiment 16, wherein the antioxidant is a combination of N,N’-hexane-1 ,6-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide) and tris(2,4-di-tert-butylphenyl) phosphite.

18. The polyamide composition according to any of preceding Embodiments, wherein the component (F) is present in an amount of from 0.01% to 5% by weight, based on the total weight of the polyamide composition.

19. The polyamide composition according to Embodiment 18, wherein the component (F) is present in an amount of from 0.02% to 2% by weight, based on the total weight of the polyamide composition.

20. The polyamide composition according to any of preceding Embodiments, wherein the polyamide as component (A) has repeating units of formula (I):

in which R¹ is a hydrocarbylene group, preferably an alkylene group, having from 3 to 29 carbon atoms.

21. The polyamide composition according to Embodiment 20, wherein R¹ is a hydrocarbylene group, preferably an alkylene group, having from 5 to 17 carbon atoms.

22. The polyamide composition according to Embodiment 21 , wherein R¹ is a hydrocarbylene group, preferably an alkylene group, from 5 to 11 carbon atoms.

23. The polyamide composition according to Embodiment 22, wherein the polyamide is polyamide 6.

24. The polyamide composition according to any of preceding Embodiments, which comprises the component (E) or the component (F). 25. The polyamide composition according to any of preceding Embodiments, which comprises the component (E) and the component (F).

26. The polyamide composition according to any of preceding Embodiments, which is free of glycerol, dipentaerythritol, triipentaerythritol, trimethylolethane, trimethylolpropane, di(trimethylolpropane), trimethylolpropane triglycidyl ether, D-mannitol, D-sorbitol, xylitol and arabitol.

27. The polyamide composition according to any of preceding Embodiments, which comprises no polyol.

28. An article, especially automobile part, obtained or obtainable from the polyamide composition according to any of Embodiments 1 to 27.

EXAMPLES

Aspects of the present invention are more fully illustrated by the following examples, which are set forth to illustrate certain aspects of the present invention and are not to be construed as limiting thereof.

Materials

Materials as used in Examples are summarized in Table 1.

Table 1

Measurements

1. Tensile strength, tensile modulus and elongation at break were measured according to ISO 527-1-2012. Test specimens of type 1 having thickness of 4 mm as described in ISO 527-1- 2012 were used. Charpy notched impact strength and Charpy unnotched impact strength were measured according to ISO 179-1-2010 via edgewise impact. Test specimens for Charpy unnotched test is type 1 specimen with the dimensions of 80 x 10 x 4mm (length x width x thickness). Test specimens for Charpy notched test are type 1 with notched type A. The test specimens were pretreated in air under a humidity of 50% at 23 °C for 16 hours.

2. The heat aging was conducted according to ISO 2578-1993 in air under 120 °C for a period of time as indicated in Table 6.

The test specimens as used were prepared according to the following general procedure.

General procedure for preparing the test specimens

Test specimens were prepared in accordance with the formulations as shown in following Tables. All raw materials except the glass fiber were mixed together in a Tubula T50A highspeed stirrer and fed into a Coperion ZSK18 MC twin-screw extruder at the throat, and the glass fiber was fed at downstream using a side feeder, then melt-extruded under a temperature of 250°C, and pelletized and dried at a temperature of 80 °C for 4 hours, thus obtaining dried pellets. The dried pellets were then processed in an injection molding machine (Haitian MA900 II) with a clamping force of 900 kN at a melt temperature of 245 °C and a molding temperature of 50 °C to provide a test specimen.

The obtained test specimens were measured for each properties as described above. The test results and the formulations for the preparation of the test specimens are summarized in following Tables. able 2

¹⁾ Increased ratio of charpy notched = (Charpy notched upon conditioning / Charpy notched at dry sate) x 100

It can be seen from the results in Table 2, the polyamide compositions (Ex. 1, Ex. 2, Ex. 3, Ex. 4, Ex. 5 and Ex. 6) according to the present invention comprising PA6 and POK at a ratio of 4 : 1 or higher have much higher impact strength and strain at break than PA6 (Comp. Ex.1), POK (Comp. Ex. 6), and comparable tensile modulus and tensile strength to PA6 (Comp. Ex.1).

Surprisingly, PA6 and POK, when used at a PA/POK ratio of 4 : 1 or greater can generate a synergistic effect on toughness improvement. That is, the toughness of each of the polyamide compositions (Ex. 1, Ex. 2, Ex. 3, Ex. 4, Ex. 5 and Ex. 6) according to the present invention is better than that of both PA6 (Comp. Ex.1) and POK (Comp. Ex.6). However, the synergistic effect was not observed for polyamide compositions having a PA/POK ratio of 3 : 1 or lower (Comp. Ex.2, Comp. Ex.3, Comp. Ex.4, Comp.Ex.5).

Moreover, the polyamide compositions according to the present invention still exhibited good tensile strength and dramatic increase of impact strength after conditioning under 85% humidity and 85 °C for 14 days. It was also observed that the polyamide compositions according to the present invention show a much higher increased ratio of impact strength (charpy notched) than both PA6 (Comp. Ex.1) and POK (Comp. Ex.6).

Table 3*

*A composition comprising POK without PA6 was not prepared successfully via twin-extruder compounding due to the high viscosity of POK M630;

¹⁾ Same as in Table 2.

The polyamide compositions (Ex.7, Ex.8, Ex.9, Ex.10) according to the present invention exhibit much higher impact strength and elongation at break than that of PA6 (Comp. Ex.1), while having comparable tensile modulus and tensile strength to PA6. Further, the polyamide compositions according to the present invention are significantly superior to the polyamide compositions having a PA/POK ratio of 1:1 or lower (Comp. Ex.7, Comp. Ex.8) in terms of tensile strength, elongation at break and impact strength. It was also observed that the polyamide compositions according to the present invention show an increased ratio of impact strength (charpy notched) much higher than that of both PA6 (Comp. Ex.1) and comparative compositions (Comp. Ex.7, Comp.Ex.8). Table 4

Toughness upon Conditioning (85 °C, 85% RH, 14 days)

¹⁾ Same as in Table 2

Table 5

¹⁾ same as in Table 2

It can be seen from the results in Tables 4 and 5, the polyamide compositions comprising POK with medium flow grade at a PA/POK ratio of 4:1 or greater also exhibit toughness improvement as discussed hereinabove. able 6

1) Tensile Strength Retention = (Tensile Strength after Aging / Initial Tensile Strength) x 100

It can be seen from the results in Table 6 that the polyamide compositions according to the present invention have improved long-term heat resistance, especially when an antioxidant component or a nigrosine component is comprised, compared with comparative compositions having a formulation not according to the present invention.

It will be apparent to one of ordinary skill in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the present invention. It is intended that the embodiments and examples be considered as exemplary only. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

Claims

1. A polyamide composition, which comprises

- a polyamide as component (A),

- a polyketone as component (B),

- a mixture of metal halides as component (C),

- a reinforcing agent as component (D),

- optionally, a nigrosine dye as component (E), and

- optionally, an antioxidant as component (F), wherein the component (A) is present in an amount of from 51 % to 68% by weight, based on the total weight of the polyamide composition, and the component (A) and the component (B) are present at a weight ratio of the component (A) to the component (B) in the range of from 3.5 : 1 or greater.

2. The polyamide composition according to claim 1 , wherein the weight ratio of the component (A) to the component (B) is in the range of from 4 : 1 to 150 : 1 , preferably in the range of from 5 : 1 to 100 : 1.

3. The polyamide composition according to claim 1 or 2, wherein the mixture of metal halides comprises or consists of a copper monohalide and an alkali metal halide, preferably is a mixture of cuprous iodide and potassium iodide.

4. The polyamide composition according to any of claims 1 to 3, wherein the component (C) is present in an amount of from 0.1 % to 3.0% by weight, or from 0.5% to 2.5% by weight, based on the total weight of the polyamide composition.

5. The polyamide composition according to any of claims 1 to 4, wherein the reinforcing agent is selected from glass fibers.

6. The polyamide composition according to any of claims 1 to 5, wherein the component (D) is present in an amount of from 10% to 50% by weight, from 10 % to 40% by weight, or from 20% to 40% by weight, based on the total weight of the polyamide composition.

7. The polyamide composition according to any of claims 1 to 6, which comprises the component (E) or the component (F), or comprises the component (E) and the component (F).

8. The polyamide composition according to any of claims 1 to 7, wherein the component (E) is present in an amount of from 0.01% to 5% by weight, from 0.02% to 2% by weight, or from 0.02% to 1% by weight, based on the total weight of the polyamide composition.

9. The polyamide composition according to any of claims 1 to 8, wherein the antioxidant is selected from hindered phenol-based antioxidants, phosphite-based antioxidants, aromatic amine-based antioxidants or any combinations thereof, preferably a combination of a hindered phenol-based antioxidant and a phosphite-based antioxidant, more preferably a combination of N,N’-hexane-1 ,6-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide) and tris(2,4-di-tert-butylphenyl) phosphite. The polyamide composition according to any of claims 1 to 9, wherein the component (F) is present in an amount of from 0.01% to 5% by weight, or from 0.02% to 2% by weight, based on the total weight of the polyamide composition. The polyamide composition according to any of claims 1 to 10, wherein the polyamide as component (A) has repeating units of formula (I):

in which

R¹ is a hydrocarbylene group, preferably an alkylene group, having from 3 to 29 carbon atoms, preferably from 5 to 17 carbon atoms, more preferably from 5 to 11 carbon atoms. The polyamide composition according to claim 11, wherein the polyamide is polyamide 6. The polyamide composition according to any of claims 1 to 12, which comprises no polyol. An article, especially automobile part, obtained or obtainable from the polyamide composition according to any of claims 1 to 13.