Polyamide compositions and articles prepared therefrom

Abstract

Disclosed is a polyamide composition comprising: a) a polyamide having a weight percentage of 80 wt% to 95 wt%; b) an acid-modified polymer having a weight percentage of 0.5 wt% to 3.8 wt%; and c) an amine-modified polymer having a weight percentage of 4.5 wt% to 17 wt%, based on the total weight of the polyamide composition, the polyamide composition having a transmittance of at least 85% measured according to CIE 15:2004. Also disclosed are methods of preparing the polyamide composition and articles prepared from the polyamide composition.

Description

[Technical Field]

[0001] The present disclosure relates to polyamide compositions and articles prepared therefrom.

[0002] background Transparent polymers have been widely used as glass substitutes. Polyamides, with their chemical and thermal stability, good processability, and mechanical strength, are candidates for a variety of optical applications, including lenses, windows, and covers.

[0003] The market demands polyamide compositions with good handling properties, high transparency, and high mechanical strength. Traditionally, transmittance and mechanical strength could be adjusted by adding auxiliary substances or additives, such as inorganic fillers, impact modifiers, and / or compatibilizers. However, it has been observed that additives can improve one set of properties at the expense of another. Therefore, there is a demand for polyamide compositions with a delicate balance of properties, particularly high transmittance, low yellowness, and high impact strength.

[0004] EP 2778190 A1 disclosed polyamide molding compounds in which an impact modifier in the form of a maleic anhydride-modified styrene-ethylene / butylene-styrene block copolymer was introduced into the polyamide composition. The use of MAH modification results in a higher yellowness index, which is undesirable for end uses such as light-transmitting components.

[0005] Summary of the Disclosure One object of the present disclosure is to provide a polyamide composition that can simultaneously achieve desired performance, including high mechanical strength, high transmittance, and good color (i.e., low yellowing).

[0006] Such an object is achieved by providing a polyamide composition comprising: a polyamide having a weight percentage of 80 wt % to 95 wt %, based on the total weight of the polyamide composition; an acid-modified polymer having a weight percentage of 0.5 wt % to 3.8 wt %; and an amine-modified polymer having a weight percentage of 3 wt % to 17 wt %, wherein the polyamide composition has a transmittance of at least 80% measured according to CIE 15:2004 at 23°C.

[0007] Preferably, the amine-modified polymer has at least a comonomer selected from ethylene, propylene, 1-butylene, 2-butylene, butadiene, and styrene.

[0008] Preferably, the acid-modified polymer has at least one first comonomer selected from ethylene, propylene, 1-butylene, 2-butylene, butadiene, and styrene, and at least one second comonomer selected from maleic anhydride, itaconic anhydride, or citraconic anhydride.

[0009] Preferably, the amine-modified polymer has a weight percentage of 4% to 15% by weight, preferably 10% to 15% by weight, based on the total weight of the polyamide composition.

[0010] Preferably, the acid-modified polymer has a weight percentage of 1% to 3.5% by weight, based on the total weight of the polyamide composition.

[0011] In a preferred embodiment of the present invention, the total weight percentage of the amine-modified polymer and the acid-modified polymer is 6% to 18% by weight based on the total weight of the polyamide composition.

[0012] Preferably, the polyamide composition has a transmittance, measured according to CIE 15:2004, of at least 85%, preferably at least 88%, more preferably at least 90%.

[0013] Preferably, the refractive index of the amine-modified polymer is in the range of 1.51 to 1.52, measured by method A according to DIN EN ISO 489:1999.

[0014] Preferably, the refractive index of the acid-modified polymer is in the range of 1.51 to 1.52, measured according to DIN EN ISO 489:1999 by method A. More preferably, the refractive index of both the amine-modified polymer and the acid-modified polymer is in the range of 1.51 to 1.52.

[0015] Preferably, the polyamide is selected from the group consisting of (a1) linear aliphatic polyamides having an average of 8 to 14 carbon atoms in the monomer units; or (a2) alicyclic polyamides based on alicyclic diamines having 10 to 20 carbon atoms and aliphatic dicarboxylic acids having 8 to 18 carbon atoms and optionally aromatic dicarboxylic acids having 8 to 18 carbon atoms; or (a3) ​​semi-aromatic polyamides based on aliphatic diamines having 2 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 18 carbon atoms; or any mixtures thereof and copolymers thereof.

[0016] Preferably, the polyamide is selected from the group consisting of: (b1) polyamide of bis(3-methyl-4-aminocyclohexyl)methane and dodecanedioic acid (PA MACM12); or (b2) polyamide of bis(4-aminocyclohexyl)methane and dodecanedioic acid (PA PACM12); or (b3) polyamide of bis(3-methyl-4-aminocyclohexyl)methane and decanedioic acid (PA MACM10); or (b4) polyamide of bis(4-aminocyclohexyl)methane and decanedioic acid (PA PACM10); or (b5) polyamide of bis(3-methyl-4-aminocyclohexyl)methane and tetradecanedioic acid (PA MACM14); or (b6) polyamide of bis(4-aminocyclohexyl)methane and tetradecanedioic acid (PA PACM14); or any mixture or copolymer thereof.

[0017] Preferably, test specimens made from the polyamide composition have a color b* value of maximum 3, measured on 2 mm thick plates according to CIE 15:2004.

[0018] Preferably, test specimens made from the polyamide composition have a color b* value of maximum 2, measured on a 2 mm thick plate according to CIE 15:2004.

[0019] Preferably, test specimens made from the polyamide composition have a thermal conductivity of 60 kJ / m, measured according to ISO 179. 2 More than 70 kJ / m 2 It has an impact strength of

[0020] Another aspect of the present invention is a method for producing the polyamide composition of the present invention. The method includes blending a polyamide, an acid-modified polymer, and an amine-modified polymer to obtain a polyamide composition. The acid-modified polymer and the amine-modified polymer can be added to the polyamide sequentially or simultaneously. Furthermore, the modified polymers can be blended by dry blending.

[0021] Another aspect of the present disclosure is to provide articles prepared from the polyamide compositions.

[0022] Detailed Description The polyamide composition according to the present disclosure includes a polyamide, an acid-modified polymer, and an amine-modified polymer. The polyamide composition can achieve high transmittance, good impact strength, and good color retention without visible yellowing.

[0023] The polyamide composition thus has reduced yellowing and high impact strength. Test specimens made from the polyamide composition have a color b* value of at most 3, preferably at most 2, measured on 2 mm thick plates according to CIE 15:2004. The test specimens have a color b* value of at most 60 kJ / m2, measured according to ISO 179. 2 more than 70 kJ / m 2It has an impact strength of

[0024] The polyamide compositions can be processed into articles by melting and forming by processes known to those skilled in the art, such as selective laser sintering, composite filament fabrication, selective thermal sintering, fused deposition modeling, fused filament fabrication, injection molding, extrusion, pressing, or rolling.

[0025] The article may be used in one of the fields of electrical equipment, sports equipment, optical equipment, sanitary and hygiene products, household equipment, communication technology, automotive technology, energy and drive technology, mechanical engineering, protective eyewear, protective shields, housings, or medical equipment.

[0026] [polyamide] The polyamides used in this disclosure are (a1) a linear aliphatic polyamide having an average of 8 to 14 carbon atoms in the monomer unit; (a2) cycloaliphatic polyamides based on cycloaliphatic diamines having 10 to 20 carbon atoms and aliphatic dicarboxylic acids having 8 to 18 carbon atoms and optionally aromatic dicarboxylic acids having 8 to 18 carbon atoms, (a3) semi-aromatic polyamides based on aliphatic diamines having 2 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 18 carbon atoms; and mixtures and copolymers thereof may include at least one selected from the group consisting of:

[0027] The polyamide composition according to the present disclosure has a transmittance, measured according to CIE 15:2004, of at least 85%, preferably at least 90%, more preferably 95%.

[0028] [Straight-chain aliphatic polyamide] Linear aliphatic polyamides have an average of 8 to 12 carbon atoms in each monomer unit. They can be prepared from a combination of diamines and dicarboxylic acids, ω-aminocarboxylic acids, and / or the corresponding lactams. The monomer units in question are therefore derived from lactams, ω-aminocarboxylic acids, diamines, or dicarboxylic acids. For example, the following polyamides are suitable: Average of 8 carbon atoms: PA88, PA79, PA97, PA610, PA106 Average of 8.5 carbon atoms: PA 89, PA98, PA611, PA116, PA512 Average of 9 carbon atoms: PA99, PA810, PA108, PA612, PA126 Average of 9.5 carbon atoms: PA910, PA109, PA811, PA118, PA613, PA136, PA514 Average of 10 carbon atoms: PA10, PA1010, PA812, PA128, PA614, PA146 Average of 10.5 carbon atoms: PA1011, PA813, PA138, PA516 Average of 11 carbon atoms: PA11, PA1012, PA1210, PA913, PA139, PA814, PA148, PA616 Average of 11.5 carbon atoms: PA1112, PA1211, PA1013, PA1310, PA914, PA149, PA815, PA617, PA518 Average of 12 carbon atoms: PA12, PA1212, PA1113, PA1014, PA1410, PA816, PA618

[0029] Suitable polyamides further include copolyamides, subject to the proviso that the monomer units contain an average of 8 to 12 carbon atoms, based on appropriate comonomer selection, such as the copolyamide (co-PA12 / 1012) composed of laurolactam, decanediamine, and dodecanedioic acid. It will be appreciated that the components used may also be mixtures of suitable polyamides, where sufficient mutual compatibility is advantageous.

[0030] Preferably used linear aliphatic polyamides are PA612, PA1010, PA1012, PA11 or PA12, particularly preferably PA11 or PA12.

[0031] [Alicyclic polyamide] Cycloaliphatic polyamides are based on cycloaliphatic diamines having 10 to 20 carbon atoms and aliphatic dicarboxylic acids having 8 to 18 carbon atoms and optionally aromatic dicarboxylic acids having 8 to 18 carbon atoms.

[0032] Preferably, the polyamide is Polyamide (PA MACM12) consisting of bis(3-methyl-4-aminocyclohexyl)methane and dodecanedioic acid, Polyamide (PA PACM12) consisting of bis(4-aminocyclohexyl)methane and dodecanedioic acid, Polyamide (PA MACM10) made from bis(3-methyl-4-aminocyclohexyl)methane and decanedioic acid, Polyamide (PA PACM10) made from bis(4-aminocyclohexyl)methane and decanedioic acid, Polyamide (PA MACM14) consisting of bis(3-methyl-4-aminocyclohexyl)methane and tetradecanedioic acid, Polyamide (PA PACM14) consisting of bis(4-aminocyclohexyl)methane and tetradecanedioic acid, and any mixtures or copolymers thereof is selected from the group consisting of:

[0033] The nomenclature used here for polyamides follows EN ISO 1874-1. Thus, PA PACMX describes a polyamide composed of monomer units derived from bis(4-aminocyclohexyl)methane (PACM) and a linear dicarboxylic acid having X carbon atoms. According to the invention, said linear dicarboxylic acid having X carbon atoms is X=8: octanedioic acid (suberic acid); X=9: Nonanedioic acid (azelaic acid); X=10: decanedioic acid (sebacic acid); X=11: undecanedioic acid; X=12: dodecanedioic acid; X = 13: Tridecanedioic acid (brassylic acid); X=14: tetradecanedioic acid; X=15: pentadecanedioic acid; X=16: hexadecanedioic acid; X=17: heptadecanedioic acid; and X=18: Octadecanedioic acid It could be.

[0034] PA PACMX is typically prepared from PACM and dicarboxylic acids by polycondensation in the melt according to known processes, however, derivatives thereof, such as diisocyanates derived from PACM, or dicarboxylic acid diesters, can also be used.

[0035] PACM exists as a mixture of cis,cis, cis,trans, and trans,trans isomers. It is commercially available in various isomer ratios. In a preferred embodiment, the trans,trans isomer content of PACM or its derivatives used is 10 to 70% by weight, more preferably 30 to 70% by weight, and particularly preferably 35 to 65% by weight, based on the total content of PACM.

[0036] It is particularly preferred if the PA PACMX is a PA PACM12 in which the trans,trans isomer content of the PACM or derivatives used is between 30 and 70% by weight, particularly preferably between 35 and 65% by weight, based on the total content of PACM.

[0037] [Semi-aromatic polyamide] Semi-aromatic polyamides are often known as polyphthalamides (PPAs). Semi-aromatic polyamides according to the present disclosure preferably contain an aliphatic diamine and an aromatic dicarboxylic acid. The aromatic dicarboxylic acid preferably has 8 to 22 carbon atoms. Semi-aromatic polyamides are prepared from a combination of a diamine and a dicarboxylic acid, optionally with the addition of an ω-aminocarboxylic acid or a corresponding lactam. Examples of suitable types include PA66 / 6T, PA6 / 6T, PA6T / MPMDT (MPMD stands for 2-methylpentamethylenediamine), PA9T, PA10T, PA11T, PA12T, PA14T, and copolycondensates of these latter types with aliphatic diamines and aliphatic dicarboxylic acids or with ω-aminocarboxylic acids and / or lactams.

[0038] Acid-modified polymers and amine-modified polymers are two families of polymers that result from modifying a base polymer with an acid / anhydride or amine functionalizing agent, respectively.

[0039] [Acid-modified polymer] Acid-modified polymers refer to a family of copolymers resulting from acid functionalization of a base polymer. Acid-modified polymers can be prepared through an acid modification process from a base polymer and an unsaturated acid or anhydride as a functionalizing agent. This acid modification can be carried out by grafting an unsaturated carboxylic acid and / or an unsaturated carboxylic acid derivative onto the base polymer. Preferably, a carboxylic acid or a carboxylic acid derivative selected from the group consisting of an unsaturated carboxylic acid ester and an unsaturated carboxylic acid anhydride is used. The conditions under which the grafting of the base polymer proceeds are well known to those skilled in the art. Acid-modified polymers contain carboxylic acid or anhydride groups introduced into the polymer by the modification process.

[0040] The unsaturated carboxylic acid is a carboxylic acid having at least one unsaturated carbon-carbon bond. Preferably, the unsaturated carboxylic acid is one or more selected from acrylic acid, methacrylic acid, alpha-ethyl acrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, aconitic acid, tetrahydrophthalic acid, and butenylsuccinic acid.

[0041] The unsaturated carboxylic acid ester is an ester of an unsaturated carboxylic acid, preferably one or more selected from the group consisting of acrylic acid, methacrylic acid, alphaethylacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, aconitic acid, tetrahydrophthalic acid, and butenylsuccinic acid.

[0042] The unsaturated carboxylic acid anhydride is an anhydride of an unsaturated dicarboxylic acid. Preferably, the unsaturated carboxylic acid anhydride is one or more selected from maleic anhydride, itaconic anhydride, or citraconic anhydride.

[0043] The base polymer may include a homopolymer or a copolymer. The homopolymer or copolymer may be an addition polymer or a condensation polymer. With regard to the addition polymer, the addition polymer may have at least one monomer or comonomer selected from ethylene, propylene, butylene, styrene, butadiene, any other olefin, (meth)acrylic acid, alkyl (meth)acrylate, (meth)acrylamide, or (meth)acrylonitrile. With regard to the condensation polymer, the condensation polymer may include one or more selected from polyether, polyester, polycarbonate, polyurethane, polyurea, polyamide, phenol-aldehyde resin, epoxy resin, polysiloxane, etc. The base polymer may include, for example, polyethylene (PE), polypropylene (PP), or styrene-ethylene-butylene-styrene copolymer (SEBS).

[0044] An exemplary acid-modified polymer has at least one first comonomer selected from ethylene, propylene, 1-butylene, 2-butylene, butadiene, and styrene, and at least one second comonomer selected from maleic anhydride, itaconic anhydride, or citraconic anhydride.

[0045] By way of example, the acid-modified polymer may include polyethylene-graft-maleic anhydride, maleic anhydride-graft PE, maleic anhydride-graft PP, styrene-maleic anhydride copolymer, maleic anhydride-methyl methacrylate copolymer, maleic anhydride-graft SEBS, or maleic anhydride-acrylamide copolymer.

[0046] According to the present disclosure, the degree of functionalization is 0.5 wt% to 2.5 wt%, preferably 1.0 wt% to 2.0 wt%, more preferably 1.2 wt% to 1.8 wt%, based on the total content of the acid-modified polymer.

[0047] The acid-modified polymer may have a refractive index similar to that of polyamide, and preferably has a refractive index within the range of 1.51 to 1.52.

[0048] In this disclosure, it has been observed that when an acid-modified polymer is added to a polyamide composition, it can improve mechanical strength and optical performance, particularly impact strength and transmittance, respectively. Without being bound by any theory, the acid-modified polymer contains terminal carboxylic acid groups that can react with unreacted amino groups in the polyamide during processing. Therefore, the acid-modified polymer can achieve high compatibility with polyamide. However, some acid-modified polymers, such as maleic anhydride-modified styrene-ethylene-butylene-styrene block copolymer (MAH-SEBS), can cause visible yellowing of the resulting polyamide composition.

[0049] [Amine-modified copolymer] In the present disclosure, it has been unexpectedly discovered that amine-modified polymers, when used as modifiers, can introduce reduced yellowing and good transmittance into polyamide compositions.

[0050] Amine-modified polymers are a family of copolymers with amino end groups. Amine-modified copolymers can be prepared from base polymers according to methods known to those skilled in the art. Exemplary methods include nitration followed by reduction, condensation followed by hydrogenation, direct amination, etc.

[0051] The base polymer may comprise a homopolymer or a copolymer. The homopolymer or copolymer may be an addition polymer or a condensation polymer. With respect to the addition polymer, the addition polymer may have at least one monomer or comonomer selected from ethylene, propylene, butylene, styrene, butadiene, any other olefin, (meth)acrylic acid, alkyl (meth)acrylate, (meth)acrylamide, or (meth)acrylonitrile. With respect to the condensation polymer, the condensation polymer may comprise one or more selected from polyethers, polyesters, polycarbonates, polyurethanes, polyureas, polyamides, phenol-aldehyde resins, epoxy resins, polysiloxanes, and the like.

[0052] As an example, the amine-modified polymer includes amine-modified polystyrene-poly(ethylene / butylene) block-polystyrene (amine-modified SEBS).

[0053] The amine-modified polymer may have a reflex index similar to that of polyamide, and preferably has a reflex index in the range of 1.51 to 1.52.

[0054] The present disclosure will be described below with reference to examples and comparative examples.

[0055] Materials and Testing The following materials were used in the examples: PA PACM12 manufactured by Evonik Specialty Chemicals (Shanghai) Co., Ltd. is a microcrystalline polyamide made from bis(4-aminocyclohexyl)methane and dodecanedioic acid with a trans,trans-stereoisomer content of 48%, which can be prepared according to the disclosure of U.S. Pat. No. 5,360,891; η rel = 1.8; enthalpy of fusion is 19 J / g.

[0056] PA MACM12 from Ems-Chemie AG is an amorphous polyamide made from bis(3-methyl-4-aminocyclohexyl)methane and dodecanedioic acid; rel =1.7; glass transition temperature 155°C.

[0057] Tafmer™ MM6850 from Mitsui Chemicals, Inc. is a maleic anhydride modified polyethylene with a maleic acid content of 2.5 wt %.

[0058] Kraton® FG1901 from Kraton Performance LLC, USA, is a styrene-ethylene / butylene-styrene block copolymer containing 30 wt% styrene grafted with 1.7 wt% maleic anhydride (MVR 130 ccm / 10 min at 275°C and 5 kg).

[0059] Tuftec™ M1913, manufactured by Asahi Kasei Corporation, is a maleic anhydride-modified SEBS thermoplastic elastomer used as a compatibilizer for polar resins or as an impact modifier for engineering plastics such as polyamides and polyesters.

[0060] Tuftec™ MP10, manufactured by Asahi Kasei Corporation, is an amine-modified styrene ethylene butadiene styrene (SEBS) thermoplastic elastomer with a polystyrene content of 30%.

[0061] The content of residual carboxylic acid groups and residual amino groups in the polymer composition was determined by titration.

[0062] For carboxylic acid groups in polyamides, the polymer composition was dissolved in benzyl alcohol under heat and then titrated at 185° C. with an ethylene glycol solution of potassium hydroxide (KOH) against phenolphthalein as an indicator.

[0063] For the amino groups in the polyamide, the polymer composition was dissolved in distilled m-cresol at 100°C and titrated potentiometrically with an ethanol solution of perchloric acid (HClO4).

[0064] For the amino groups in Tuftec™ MP10, the polymer composition was dissolved in tetrahydrofuran (THF) and titrated potentiometrically with aqueous hydrogen chloride (HCl).

[0065] The notched impact strength was measured according to ISO 179 / 1eA (Charpy) on 80 mm x 10 mm x 4 mm double-cut tensile specimens ISO 527 Type 1A at a temperature of (23 ± 2) °C and a relative humidity of (50 ± 10) % by a CEAST Resil Impactor 6967.000.

[0066] The yellowing of the polymer composition is determined by measuring the CIE L*, a*, b* color (D65 / 10).

[0067] CIE L*, a*, b* color (D65 / 2) and transmittance (Y) were determined using a Konica Minolta CM-3600d spectrophotometer. "L*" represents the sample's lightness (100-0) on the CIE L*, a*, b* scale, "a*" represents reddish (+) or greenish (-), and "b*" represents yellowish (+) or blueish (-). This scale is based on the principles described in ASTM E 308 Standard Practice for Computing the Colors of Objects by Using the CIE System. Sample thickness was 2 mm. Measurements were based on CIE 15:2004. [Example]

[0068] All polyamide compositions were mixed using a Coperion ZSK-26cm co-rotating twin-screw extruder, discharged, and pelletized to obtain polymer composites according to the recipes shown in Tables 1 and 2. The polyamide was fed into the main port of the extruder and then mixed at 280°C, and the modifier was simultaneously fed into the extruder.

[0069] The polymer compositions in pellet form were processed in an injection molding machine Engel VC 650 / 200 (melt temperature 280° C.; mold temperature 60° C.) to prepare test specimens for mechanical performance testing and optical testing.

[0070] The mechanical and optical results of samples made from the polyamide compositions of Examples (E1-E6), Comparative Examples (C1-C4), and Raw Materials (R1 and R2) are shown in Tables 1 and 2. The COOH and amine contents in the composition of Comparative Example C4 were not shown due to their low solubility in the solvents mentioned above. It is noteworthy that specimens could not be prepared from the polyamide composition of Comparative Example C4 because of insufficient mechanical strength. This is thought to be partly due to poor compatibility when the impact modifier MP10 content was as high as 20 wt%. Therefore, compositions containing impact modifiers with a content greater than 20 wt% were not experimented with or tested. [Table 1] [Table 2]

[0071] It can be observed that acid-functionalized impact modifiers with a refractive index of 1.51-1.52 can provide higher impact strength to transparent nylon while maintaining good transmittance. However, the resulting mixtures are usually yellow in color (Comparative Examples C1 and C2).

[0072] Amine-functionalized impact modifiers with a reflective index of 1.51 to 1.52 can provide less yellowing and good transmission.

[0073] Introducing a small amount of an acid modifier as a compatibilizer into an amine impact modifier system can improve impact strength while achieving good color and high transmittance (Examples E1-E6).

[0074] Various aspects and embodiments are possible, some of which are described herein, and after reading this specification, those skilled in the art will understand that these aspects and embodiments are merely exemplary and do not limit the scope of the disclosure.

Claims

1. based on the total weight of the polyamide composition, a polyamide having a weight percentage of 80% to 95% by weight; an acid-modified polymer having a weight percentage of 0.5 wt % to 3.8 wt %; an amine-modified polymer having a weight percentage of 3% to 17% by weight; 1. A polyamide composition comprising:

2. 10. The polyamide composition of claim 1, wherein the amine-modified polymer has at least one comonomer selected from ethylene, propylene, 1-butylene, 2-butylene, butadiene, and styrene.

3. 2. The polyamide composition of claim 1, wherein the acid-modified polymer has at least one first comonomer selected from ethylene, propylene, 1-butylene, 2-butylene, butadiene, and styrene, and at least one second comonomer selected from maleic anhydride, itaconic anhydride, or citraconic anhydride.

4. 4. The polyamide composition according to any one of claims 1 to 3, wherein the amine-modified polymer has a weight percentage of from 4 wt% to 15 wt%, based on the total weight of the polyamide composition.

5. 5. The polyamide composition according to claim 1, wherein the acid-modified polymer has a weight percentage of from 1 wt. % to 3.5 wt. %, based on the total weight of the polyamide composition.

6. 6. The polyamide composition according to claim 1, wherein the sum of the weight percentages of the amine-modified polymer and the acid-modified polymer is from 6 wt % to 18 wt %, based on the total weight of the polyamide composition.

7. 7. Polyamide composition according to any one of claims 1 to 6, having a transmittance, measured according to CIE 15:2004, of at least 88%, preferably 90%.

8. 8. The polyamide composition according to any one of claims 1 to 7, wherein the refractive index of the amine-modified polymer or the acid-modified polymer is in the range of 1.51 to 1.52, measured according to DIN EN ISO 489:1999 by method A.

9. The polyamide (a1) a linear aliphatic polyamide having an average of 8 to 14 carbon atoms in the monomer unit; or (a2) cycloaliphatic polyamides based on cycloaliphatic diamines having 10 to 20 carbon atoms and aliphatic dicarboxylic acids having 8 to 18 carbon atoms and optionally aromatic dicarboxylic acids having 8 to 18 carbon atoms; or (a3) semi-aromatic polyamides based on aliphatic diamines having 2 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 18 carbon atoms; or Mixtures thereof and copolymers thereof 9. The polyamide composition of claim 1, selected from the group consisting of:

10. The polyamide (b1) a polyamide consisting of bis(3-methyl-4-aminocyclohexyl)methane and dodecanedioic acid (PA MACM12); or (b2) polyamide consisting of bis(4-aminocyclohexyl)methane and dodecanedioic acid (PA PACM12); or (b3) polyamide of bis(3-methyl-4-aminocyclohexyl)methane and decanedioic acid (PA MACM10); or (b4) polyamide of bis(4-aminocyclohexyl)methane and decanedioic acid (PA PACM10); or (b5) polyamide consisting of bis(3-methyl-4-aminocyclohexyl)methane and tetradecanedioic acid (PA MACM14); or (b6) Polyamide consisting of bis(4-aminocyclohexyl)methane and tetradecanedioic acid (PA PACM14); or any mixture or copolymer thereof 10. The polyamide composition of claim 1, selected from the group consisting of:

11. 11. The polyamide composition according to any one of claims 1 to 10, wherein test specimens made from the polyamide composition have a colour b* value of maximum 3, measured on 2 mm thick plates according to CIE 15:2004.

12. 12. The polyamide composition according to any one of claims 1 to 11, wherein test specimens made from the polyamide composition have a colour b* value of maximum 2, measured on a 2 mm thick plate according to CIE 15:2004.

13. Test specimens made from the polyamide composition have a thermal shock resistance of 60 kJ / m2, measured according to ISO 179. ２ More than 70 kJ / m ２ 13. The polyamide composition according to claim 1, having a notched impact strength of

14. 14. A method for making the polyamide composition of any one of claims 1 to 13 by blending the polyamide, the acid-modified polymer, and the amine-modified polymer.

15. 15. An article prepared from the polyamide composition of any one of claims 1 to 14.

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