A semi-aromatic polyamide composition, a method for preparing the same and use thereof

Abstract

The application discloses a semi-aromatic polyamide composition, which comprises the following components in parts by weight: 79-101 parts of semi-aromatic polyamide; 5-30 parts of a maleic anhydride grafting type toughening agent; and 3-8 parts of an amine type coolant resistant modifier. The semi-aromatic polyamide composition of the application has the advantages of good coolant resistance, and the melting point of the composition can be controlled to be 170-200 DEG C, so that the semi-aromatic polyamide composition is suitable for the preparation of a liquid cooling pipe of a new energy vehicle.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a semi-aromatic polyamide composition, its preparation method, and its application. Background Technology

[0002] The fundamental changes in the power systems of new energy vehicles, especially pure electric vehicles, are reshaping the architecture of automotive thermal management systems. Compared to traditional gasoline vehicles, electric vehicles require further improvements in thermal management efficiency. New energy vehicle cooling systems can be categorized by the cooling medium into air cooling, liquid cooling, and phase change materials. Liquid cooling is currently the primary cooling method for new energy vehicles, including water cooling and oil cooling. Coolant piping, as a crucial component of new energy vehicles, needs to meet various requirements such as resistance to hydrolysis, oil resistance, high temperature resistance, and lightweight design.

[0003] Currently, rubber hoses are rarely used due to their poor environmental adaptability or low cooling efficiency. Silicone hoses, for example, have low cooling efficiency, are heavy, and are prone to aging. Nylon hoses, due to their light weight and simple processing, have gradually become the main material used in coolant piping. Nylons used in coolant piping are mainly aliphatic and aromatic. Aliphatic nylons are represented by PA11, PA12, and PA612, while aromatic nylons are represented by PA9T and PA11T. Nylon plastic tubing can be used in motor compartments, chassis, and battery packs. The appropriate temperature resistance rating and structural type of nylon material are selected based on the different temperature, pressure, and assembly requirements of each location. However, these aliphatic nylons are not very resistant to coolant and often need to be made into multi-layer structures. For example, PA11 and PA12 materials need to be made into three- or five-layer pipelines with barrier materials such as EVOH, ETFE, and EFEP to meet the requirements of long-term use. PA612 has even worse resistance to hydrolysis and alcoholysis and can only be used as a cost reduction solution for PA11 and PA12. It is currently used less frequently.

[0004] For cooling pipes used in new energy electric vehicles, the materials must possess both low melting point and easy processing characteristics, as well as excellent resistance to coolant to maintain long-term performance. Elongation at break is a key indicator for pipe materials, closely related to the elongation, burst, and dynamic fatigue performance of the molded pipes. It is generally believed in the industry that an elongation at break >150% is necessary to meet the requirements of elongation, burst, and dynamic fatigue testing for pipes, ensuring the production of qualified pipes; while when the elongation at break <20%, the material's service life has reached its limit. Therefore, testing the initial and coolant-resistant elongation at break can indicate whether the polyamide composition is suitable for pipes.

[0005] Patent CN118063957A discloses a flexible, hydrolysis-resistant extruded polyamide material, mainly comprising 20-52% polyamide resin, 20-50% polyphenylene ether resin, 3-7% compatibilizer, 8-14% toughening agent, 10-14% composite plasticizer, 0.3-0.6% antioxidant, and 0.4-0.7% lubricant. This patent primarily uses aliphatic polyamides such as PA6 and PA612 as the resin matrix, which exhibits poor resistance to coolant. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned technical defects and provide a semi-aromatic polyamide composition that has good resistance to coolant and suitable processing temperature.

[0007] This invention is achieved through the following technical solution:

[0008] A semi-aromatic polyamide composition, comprising, by weight, the following components:

[0009] 79-101 parts of semi-aromatic polyamide;

[0010] 5-30 parts of maleic anhydride grafted toughening agent;

[0011] 3-8 parts of amine-based coolant-resistant modifier;

[0012] The semi-aromatic polyamide, in molar percentage, is derived from the following units:

[0013] The diacid unit is derived from terephthalic acid and other straight-chain diacids, wherein terephthalic acid accounts for 10-30 mol% of the diacid unit molar content, and the other straight-chain diacids are selected from at least one of 1,10-decanedioic acid, 1,12-dodecanoic acid, and 1,18-octadecanoic acid, wherein 1,10-decanedioic acid accounts for 40-100 mol% of the total molar percentage content of the other straight-chain diacids.

[0014] The diamine units are derived from 1,10-decanediamine and 1,12-dodecanediamine, with 1,10-decanediamine accounting for 30-100 mol% of the total diamine units.

[0015] The amine-based coolant modifier is selected from at least one of N-ethyl-p-toluenesulfonamide, dendritic polyamide amine (PAMAM), 4,4'-methylenebis(3-chloro-2,6-diethylaniline), N,N'-bis(2,6-diisopropylphenyl)carbodiimide, and diethyltoluenediamine.

[0016] Preferably, terephthalic acid accounts for 15-25 mol% of the diacid unit, 1,10-sebacic acid accounts for 80-100 mol% of the total molar percentage of other straight-chain diacids, and 1,10-decanediamine accounts for 60-100 mol% of the total molar percentage of the diamine unit.

[0017] In the semi-aromatic polyamide composition of the present invention, the semi-aromatic polyamide accounts for not less than 60 wt% of the total weight.

[0018] Preferably, the content of the amine-based coolant modifier is 4-6 parts.

[0019] Preferably, the amine-based coolant modifier is selected from at least one of N-ethyl-p-toluenesulfonamide and dendritic polyamide amine;

[0020] A more preferred amine-based coolant-resistant modifier is dendritic polyamide amine.

[0021] The melting point range of the semi-aromatic polyamide of this invention is 170-200℃. It was tested using a differential scanning calorimeter (DSC) according to ISO 11357-3-2018 standard.

[0022] The relative viscosity range of the semi-aromatic polyamide of this invention is 2.0-3.2. The test method is as follows: referring to GB12006.1-89, method for determining the viscosity of polyamide; specifically, the relative viscosity ηr of polyamide with a concentration of 0.25 g / dl is measured in 98% concentrated sulfuric acid at 25±0.01℃.

[0023] The semi-aromatic polyamide of this invention can be a commercially available product or can be prepared in-house. The preparation method is as follows: Add the reactant monomer, benzoic acid, sodium hypophosphite, and deionized water to a pressure vessel; the amount of benzoic acid is 1-3% of the total amount of diamine and diacid; the weight of sodium hypophosphite is 0.05-0.15% of the total weight of the other ingredients excluding deionized water; and the weight of deionized water is 20-40% of the total weight of the ingredients. Evacuate the vessel and purge it with high-purity nitrogen as a protective gas. Heat the vessel to 190-210°C over 1.5-2.5 hours with stirring. Stir the reaction mixture at 190-210°C for 0.5-1.5 hours, then raise the temperature of the reactants to 260-280°C with stirring. Continue the reaction at 260-280°C and a constant pressure of 3.0-3.4 MPa for 1-3 hours. Maintain a constant pressure by removing the formed water, then gradually reduce the pressure to atmospheric pressure. After the reaction is complete, discharge the product to obtain the polyamide resin.

[0024] The maleic anhydride-grafted toughening agent is selected from at least one of maleic anhydride-grafted POE, maleic anhydride-grafted SEBS, and maleic anhydride-grafted EPDM; preferably, maleic anhydride-grafted POE.

[0025] In the maleic anhydride grafted toughening agent, the grafting rate of maleic anhydride is 1-5 wt%, preferably 2-3 wt%.

[0026] Maleic anhydride grafted toughening agents can be commercially available products or obtained by self-production. Self-production methods include, but are not limited to: mixing initiator (dicumyl peroxide, benzoyl peroxide), unmodified toughening agent, and maleic anhydride in a designed ratio (the amount of initiator added shall not exceed 0.3wt% of the total feed amount), and mixing them in a mixer at a temperature range of 180-220℃.

[0027] The test method for maleic anhydride content is acid-base titration. The specific procedure is as follows: the copolymer is dissolved in xylene under reflux. After cooling, a certain amount of 0.05 mol / L potassium hydroxide-ethanol solution is added, and the mixture is refluxed again for 8 hours. Using 0.1% phenolphthalein solution as an indicator, the solution is titrated to the endpoint with 0.05 mol / L HCl-isopropanol solution while hot. The weight content G is calculated using the following formula:

[0028] G = (N1 × Vl - N2 × V2) × M ÷ w ÷ 10

[0029] In the formula: N1: KOH—equivalent concentration of ethanol solution, N;

[0030] V1: Volume of KOH ethanol solution, ml;

[0031] N2: Equivalent concentration of HCl-isopropanol solution, N;

[0032] V2: Volume of HCl-isopropanol solution, in ml;

[0033] M: Equivalent mass of maleic anhydride, g;

[0034] w: Mass of the dried sample after extraction, in g.

[0035] Those skilled in the art can choose whether to add 0-3 parts of additives according to actual needs. The additives are selected from at least one of UV stabilizers, heat stabilizers, and pigments.

[0036] The method for preparing the semi-aromatic polyamide composition of the present invention includes the following steps: mixing the components evenly according to the formula, and granulating by extrusion through a twin-screw extruder to obtain the semi-aromatic polyamide composition.

[0037] The semi-aromatic polyamide composition of the present invention has an elongation at break of >180% and a coolant retention rate of >25%, making it suitable for the preparation of liquid-cooled pipelines.

[0038] The present invention has the following beneficial effects:

[0039] This invention introduces a specific molar amount of benzene ring structure into a long carbon chain structure. By utilizing the chemical resistance and self-barrier properties of the benzene ring structure, the material not only possesses the excellent toughness of long carbon chain polyamides, but also effectively prevents the coolant from penetrating into the material's interior during prolonged contact with coolant, thus reducing the occurrence of alcoholysis and hydrolysis effects in the polyamide material and significantly improving the material's performance after aging.

[0040] The invention makes an unexpected discovery: by adding a toughening agent grafted with maleic anhydride to the material, the reaction of maleic anhydride with the carboxyl end groups in the polyamide forms a capping effect. This reduces the attack effect of ethylene glycol / water and oxygen on the carboxyl end groups of the material during contact with coolant, thereby effectively reducing the chain reaction caused by the formation of active free radicals due to chain breakage, reducing material degradation, and improving the performance of the material after aging.

[0041] Furthermore, in this invention, by adding an amine-based coolant aging resistant agent, the activity of the polyamide molecular chain is improved, and it can combine with the active free radicals generated by molecular chain scission, preventing the free radicals from further attacking other chain segments and causing severe degradation of the material, thus effectively improving the material's coolant aging resistance.

[0042] In summary, this invention utilizes a benzene ring structure with a specific molar content to reduce coolant penetration into the material, utilizes the end-capping effect of maleic anhydride toughening agent to improve the stability of the polyamide molecular chain, and utilizes amine-based coolant-resistant aging agents to reduce free radicals formed by chain breakage. These three elements work together to effectively improve the material's coolant resistance. Detailed Implementation

[0043] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0044] The raw materials used in this invention are sourced from the following sources:

[0045] The following polyamide resins were obtained in-house:

[0046] A-1 A-2 A-3 A-4 A-5 A-6 A-7 terephthalic acid mol 1 1.5 1.9 2.5 3 0.5 3.5 1,10-Sebacic acid mol 9 8.5 8.1 7.5 7 9.5 6.5 1,10-decanediamine mol 10 10 10 10 10 10 10 Melting point, °C 175 178 180 185 192 166 206 relative viscosity 2.6 2.6 2.6 2.6 2.6 2.6 2.6

[0047] B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8 terephthalic acid mol 1.5 1.5 1.5 1.5 0.5 3.5 1.5 1.5 1,10-Sebacic acid mol 3.4 3.4 6.8 6.8 7.6 5.2 1.7 1.7 1,12-Dodecanedioic acid mol 5.1 1.7 1.9 1.3 6.8 6.8 1,18-octadecanoic acid mol 5.1 1.7 1,10-decanediamine mol 3 3 6 6 6 6 2 10 1,12-Dodecanediamine mol 7 7 4 4 4 4 8 Melting point, °C 173 172 174 172 163 203 171 172 relative viscosity 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6

[0048] N-Ethyl-p-Toluenesulfonamide: NEO / PTSA, Shouguang Nuomeng Chemical Co., Ltd.;

[0049] Dendritic polyamide amine: CYD-120C, Weihai Chenyuan Molecular New Materials Co., Ltd.;

[0050] 4,4'-Methylenebis(3-chloro-2,6-diethylaniline): MCDEA, Jinwotai Chemical Co., Ltd.;

[0051] N,N'-Di(2,6-Diisopropylphenyl)carbodiimide: BCM-011, Zhejiang Pukang Chemical Co., Ltd.;

[0052] Diethyltoluenediamine: E-100, Shandong Tonglan Chemical Co., Ltd.;

[0053] Maleic anhydride-grafted POE-1: Maleic anhydride grafting rate of 1wt%, prepared by mixing;

[0054] Maleic anhydride-grafted POE-2: Maleic anhydride grafting rate of 2wt%, prepared by mixing;

[0055] Maleic anhydride-grafted POE-3: Maleic anhydride grafting rate of 3wt%, prepared by mixing;

[0056] Maleic anhydride-grafted POE-4: Maleic anhydride grafting rate of 5wt%, prepared by mixing;

[0057] The POE grafted with maleic anhydride mentioned above is derived from POE DF640, Mitsui Chemicals, Singapore.

[0058] Maleic anhydride-grafted SEBS: The maleic anhydride grafting rate is 2.5 wt%, and it is produced in-house through compounding. The SEBS is derived from Kraton G1652, Shell, USA.

[0059] Maleic anhydride-grafted EPDM: The maleic anhydride grafting rate is 2.5 wt%. The maleic anhydride grafting rate is increased by mixing. The maleic anhydride-grafted EPDM before further modification is derived from FUSABOND N416, DuPont, USA.

[0060] GMA grafted POE: POG-2821, Guangzhou Dongjin Plastics Technology Co., Ltd.;

[0061] GMA grafted SEBS: KT-2511, Shenyang Ketong Company;

[0062] POE: POE DF640, Mitsui Chemicals, Singapore.

[0063] Antioxidant: RIANOX 1098, Lianlong Company;

[0064] Carbon black: M717, Cabot Corporation;

[0065] Test methods:

[0066] (1) Coolant resistance: First, the initial elongation at break was tested. The semi-aromatic polyamide composition was heated and melted at 220~260℃ and injection molded into tensile specimens A and B. The tensile properties of specimen A were tested according to the international standard ISO 527-2019 to obtain the initial elongation at break. Specimen B was placed in an autoclave, and ethylene glycol and deionized water were mixed evenly at a volume ratio of 1:1 and poured into the autoclave until the tensile specimen was completely submerged. Then, the autoclave was placed in a high-temperature oven at 135℃ for 2000h and then taken out. The tensile properties of the aged tensile specimens were tested according to the international standard ISO 527-2019 to obtain the elongation at break after aging. The coolant resistance retention rate was calculated as the elongation at break after coolant test / initial elongation at break × 100%.

[0067] Table 1: Content of each component and test results of the semi-aromatic polyamide compositions in Examples 1-6

[0068] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Polyamide resin A-1 80 90 100 90 90 90 Maleic anhydride grafted onto POE-1 10 5 30 5 5 5 N-Ethyl-p-toluenesulfonamide 3 4 8 3 6 8 antioxidants 0.5 carbon black 0.5 Initial elongation at break % 210 203 225 198 209 218 Coolant retention rate % 28 33 34 27 31 28

[0069] As can be seen from Examples 2 / 4 / 5 / 6, the preferred N-butylbenzenesulfonamide content results in a higher coolant retention rate.

[0070] Table 2: Content of each component and test results of the semi-aromatic polyamide compositions in Examples 7-11

[0071] Example 7 Example 8 Example 9 Example 10 Example 11 Polyamide resin A-1 90 90 90 90 90 Maleic anhydride grafted onto POE-2 5 Maleic anhydride grafted onto POE-3 5 Maleic anhydride grafted onto POE-4 5 maleic anhydride grafted SEBS 5 Maleic anhydride grafted onto EPDM 5 N-Ethyl-p-toluenesulfonamide 4 4 4 4 4 Initial elongation at break % 210 216 215 192 195 Coolant retention rate % 35 36 30 32 31

[0072] As can be seen from Examples 2 / 7-11, the optimal maleic anhydride content results in a higher coolant retention rate.

[0073] Table 3: Content of each component and test results of the semi-aromatic polyamide compositions in Examples 12-15

[0074] Example 12 Example 13 Example 14 Example 15 Polyamide resin A-1 90 90 90 90 Maleic anhydride grafted onto POE-1 5 5 5 5 Dendritic polyamide 4 4,4'-Methylenebis(3-chloro-2,6-diethylaniline) 4 N,N'-Di(2,6-diisopropylphenyl)carbodiimide 4 Diethyltoluenediamine 4 Initial elongation at break % 196 193 195 197 Coolant retention rate % 35 28 30 29

[0075] As shown in Comparative Examples 2 / 12-15, from the perspective of improving coolant retention rate, the preferred amine coolant modifiers are N-butylbenzenesulfonamide and resinous polyamide amine, and dendritic polyamide amine is even better.

[0076] Table 4: Content of each component and test results of the semi-aromatic polyamide compositions in Examples 16-20

[0077] Example 16 Example 17 Example 18 Example 19 Example 20 Polyamide resin grade A-2 A-3 A-4 A-5 B-1 polyamide resin content 90 90 90 90 90 Maleic anhydride grafted onto POE-1 5 5 5 5 5 N-Ethyl-p-toluenesulfonamide 4 4 4 4 4 Initial elongation at break % 200 196 192 176 212 Coolant retention rate % 35 36 37 39 30

[0078] As can be seen from Examples 2 / 16-19, when the molar content of terephthalic acid in the diacid unit is preferably 15-25 mol%, the initial elongation at break is higher, resulting in a significantly higher elongation at break after the coolant resistance test.

[0079] Table 5: Content of each component and test results of the semi-aromatic polyamide compositions in Examples 21-23

[0080] Example 21 Example 22 Example 23 Polyamide resin grade B-2 B-3 B-4 polyamide resin content 90 90 90 Maleic anhydride grafted onto POE-1 5 5 5 N-Ethyl-p-toluenesulfonamide 4 4 4 Initial elongation at break % 223 214 209 Coolant retention rate % 29 33 34

[0081] As can be seen from Examples 20-23, 1,10-decanediamine preferably accounts for 60-100 mol of the total molar percentage of the diamine units.

[0082] Table 6: Content of each component and test results of semi-aromatic polyamide compositions in Comparative Examples 1-5

[0083] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Polyamide resin grade A-1 A-1 A-1 A-1 A-1 polyamide resin content 90 90 90 90 90 Maleic anhydride grafted onto POE-1 5 5 GMA grafted POE 5 GMA grafted with SEBS 5 POE 5 N-Ethyl-p-toluenesulfonamide 4 4 4 1 10 Initial elongation at break % 178 183 143 192 226 Coolant retention rate % 16 17 13 18 20

[0084] As shown in Comparative Examples 1 / 2 / 3, although the GMA-grafted toughening agent can also react with the end groups of polyamide compared to the ungrafted toughening agent, its effect on improving coolant resistance is not significant enough.

[0085] As shown in Comparative Example 4, if the content of N-ethyl-p-toluenesulfonamide is insufficient, the improvement in coolant resistance is not significant enough.

[0086] As shown in Comparative Example 5, if the content of N-ethyl-p-toluenesulfonamide is too high, the coolant retention rate will actually decrease.

[0087] Table 7: Content of each component and test results of the semi-aromatic polyamide compositions of Comparative Examples 6-11

[0088] Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 Comparative Example 11 Polyamide resin grade A-6 A-7 B-5 B-6 B-7 B-8 polyamide resin content 90 90 90 90 90 90 Maleic anhydride grafted onto POE-1 5 5 5 5 5 5 N-Ethyl-p-toluenesulfonamide 4 4 4 4 4 4 Initial elongation at break % 217 143 228 146 212 209 Coolant retention rate % 15 40 13 36 21 22

[0089] As shown in Comparative Example 6 / 8, if the content of terephthalic acid in dicarboxylic acid is too low, the coolant retention rate will be low.

[0090] As shown in Comparative Example 7 / 9, if the content of terephthalic acid in diacid is too high, although the coolant retention rate is high, the initial elongation at break does not meet the industry requirements.

[0091] As can be seen from Comparative Example 10, even if the content of terephthalic acid as a dicarboxylic acid is within the range of the present invention, the content of 1,10-decanediamine as a diamine is too low, resulting in a low coolant retention rate.

[0092] As can be seen from Comparative Example 11, if the content of terephthalic acid as a dicarboxylic acid is within the range of the present invention, but the content of 1,10-sebacic acid as a dicarboxylic acid is too low, the coolant retention rate is low.

Claims

1. A semi-aromatic polyamide composition, characterized in that, By weight, it includes the following components: 79-101 parts of semi-aromatic polyamide; 5-30 parts of maleic anhydride grafted toughening agent; 3-8 parts of amine-based coolant-resistant modifier; The semi-aromatic polyamide, in molar percentage, is derived from the following units: The diacid unit is derived from terephthalic acid and other straight-chain diacids, wherein terephthalic acid accounts for 10-30 mol% of the diacid unit molar content, and the other straight-chain diacids are selected from at least one of 1,10-decanedioic acid, 1,12-dodecanoic acid, and 1,18-octadecanoic acid, wherein 1,10-decanedioic acid accounts for 40-100 mol% of the total molar percentage content of the other straight-chain diacids. The diamine units are derived from 1,10-decanediamine and 1,12-dodecanediamine, with 1,10-decanediamine accounting for 30-100 mol% of the total diamine units. The amine-based coolant modifier is selected from at least one of N-ethyl-p-toluenesulfonamide, dendritic polyamide amine, 4,4'-methylenebis(3-chloro-2,6-diethylaniline), N,N'-bis(2,6-diisopropylphenyl)carbodiimide, and diethyltoluenediamine.

2. The semi-aromatic polyamide composition according to claim 1, characterized in that, Terephthalic acid accounts for 15-25 mol% of the diacid unit, 1,10-sebacic acid accounts for 80-100 mol% of the total molar percentage of other straight-chain diacids, and 1,10-decanediamine accounts for 60-100 mol% of the total molar percentage of the diamine unit.

3. The semi-aromatic polyamide composition according to claim 1, characterized in that, The content of the amine-based coolant modifier is 4-6 parts.

4. The semi-aromatic polyamide composition according to claim 1, characterized in that, The amine-based coolant modifier is selected from at least one of N-ethyl-p-toluenesulfonamide and dendritic polyamide amine.

5. The semi-aromatic polyamide composition according to claim 4, characterized in that, The amine-based coolant-resistant modifier is selected from dendritic polyamide amines.

6. The semi-aromatic polyamide composition according to claim 1, characterized in that, The melting point range of the semi-aromatic polyamide is 170-200℃.

7. The semi-aromatic polyamide composition according to claim 1, characterized in that, The maleic anhydride grafted toughening agent is selected from at least one of maleic anhydride grafted POE, maleic anhydride grafted SEBS, and maleic anhydride grafted EPDM; the grafting rate of maleic anhydride in the maleic anhydride grafted toughening agent is 1-5 wt%.

8. The semi-aromatic polyamide composition according to claim 7, characterized in that, The maleic anhydride-grafted toughening agent is selected from maleic anhydride-grafted POE; in the maleic anhydride-grafted toughening agent, the grafting rate of maleic anhydride is 2-3 wt%.

9. The semi-aromatic polyamide composition according to claim 1, characterized in that, The product also includes 0-3 parts by weight of additives, wherein the additives are selected from at least one of UV stabilizers, heat stabilizers, and pigments.

10. A method for preparing the semi-aromatic polyamide composition according to any one of claims 1-9, characterized in that, The process includes the following steps: mixing the components evenly according to the formula, and granulating the mixture by extrusion through a twin-screw extruder to obtain a semi-aromatic polyamide composition.

11. The use of the semi-aromatic polyamide composition according to any one of claims 1-9, characterized in that, Used for manufacturing liquid cooling pipelines.

12. A pipe prepared using any one of the semi-aromatic polyamide compositions of claims 1-9.