PA56 composite material, preparation method and application thereof

Abstract

The application discloses a PA56 composite material and a preparation method and application thereof, and belongs to the technical field of high polymer materials. The PA56 composite material comprises the following components in parts by weight: 28-82 parts of PA56 resin, 2.8-42 parts of copolymerized polyamide, 1-50 parts of glass fiber, 0.09-0.6 parts of lubricant and 0.2-2 parts of auxiliary agent. The PA56 composite material has excellent impact strength, a high crystallization temperature and a short cooling time, can realize rapid forming, and can be widely applied to fields with high requirements on cooling periods.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a PA56 composite material, its preparation method, and its application. Background Technology

[0002] Nylon 56, also known as PA56, is a bio-based nylon material produced by the condensation polymerization of pentanediamine and adipic acid. It is environmentally friendly, has excellent performance, and improves the comfort of finished fabrics. Its water absorption, glass transition temperature, strength, softness, moisture absorption, and resilience are superior to some products of nylon 6, nylon 66, and polyester. Furthermore, PA56 chips can be processed into plastic products, and PA56 fibers can also be obtained through melt spinning.

[0003] Because PA56 is an odd-even nylon, its crystallization rate is lower than that of the traditional even-even nylon PA66. Its slow cooling rate, long molding cycle, and low production efficiency severely restrict its widespread use. Therefore, improving the crystallization rate of bio-nylons, accelerating cooling, and shortening the molding cycle are of significant practical importance. Traditionally, adding nucleating agents increases the crystallization rate of crystalline materials, but these agents can lead to brittleness. For PA56, which lacks inherent toughness, maintaining a certain level of impact toughness is essential to ensure that parts possess resistance to bending, impact, and low-temperature performance at corners and thin-walled sections.

[0004] CN111087801A discloses a bio-based polyamide 56 material for thermal insulation strips, its preparation method, and the thermal insulation strip itself. By adding a nucleating agent to the PA56 material, the crystallization rate during the preparation process of the bio-based polyamide 56 material for thermal insulation strips is accelerated, shortening the extrusion molding cycle. However, due to the addition of the nucleating agent, the material's impact toughness is only 5 kJ / m. 2 This makes it difficult to apply to components that require high impact toughness.

[0005] Therefore, how to improve the crystallization rate of bio-nylon and avoid making the material brittle has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a PA56 composite material, its preparation method and application. The PA56 composite material has excellent impact strength, high crystallization temperature and short cooling time, and can achieve rapid molding.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A PA56 composite material comprises the following components in parts by weight: 28-82 parts PA56 resin, 2.8-42 parts copolyamide, 1-50 parts glass fiber, 0.09-0.6 parts lubricant, and 0.2-2 parts additives;

[0009] The structural formula of the copolyamide is shown in Formula I:

[0010]

[0011] In Formula I, m / n = (1-5): (5-9).

[0012] This invention combines the above-mentioned raw materials in specific weight proportions to obtain a PA56 composite material with excellent impact strength, high crystallization temperature, and short cooling time, which can be rapidly molded. The PA56 composite material can be widely used in fields with high requirements for cooling cycles.

[0013] This invention creatively employs the above-mentioned specific structural formula of copolyamide, which is combined with PA56 in the above-mentioned specific weight parts. This combination can induce nucleation, effectively increase the crystallization temperature, shorten the cooling time, and accelerate the molding cycle. It achieves the effect of promoting crystallization from the molecular structure, avoiding the technical drawbacks of the previous method of adding nucleating agents, which resulted in the material being too brittle.

[0014] The amount of PA56 used is 28 to 82 parts, for example, it can be 28 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 82 parts or any two of these values.

[0015] Preferably, the amount of PA56 used is 30 to 80 parts.

[0016] The amount of the copolyamide is 2.8 to 42 parts, for example, it can be 2.8 parts, 3 parts, 5 parts, 10 parts, 20 parts, 30 parts, 40 parts, 42 parts or any two of these values.

[0017] Preferably, the amount of the copolyamide is 3 to 40 parts.

[0018] The amount of glass fiber used is 1 to 50 parts, for example, it can be 1 part, 5 parts, 10 parts, 20 parts, 30 parts, 40 parts, 50 parts or any two of these values.

[0019] Preferably, the amount of glass fiber used is 10 to 40 parts.

[0020] The amount of the lubricant used is 0.09 to 0.6 parts, for example, it can be 0.09 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, or any two of these values.

[0021] Preferably, the amount of the lubricant used is 0.1 to 0.5 parts.

[0022] Preferably, the amount of the adjuvant is 0.2 to 2 parts, for example, it can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts or any two of these values.

[0023] Preferably, the amount of the auxiliary agent is 0.4 to 1 part.

[0024] Preferably, the PA56 composite material comprises the following components in parts by weight: 30-80 parts PA56 resin, 3-40 parts copolyamide, 1-50 parts glass fiber, 0.1-0.5 parts lubricant, and 0.4-1 parts additives.

[0025] Preferably, the PA56 composite material comprises the following components in parts by weight: 50-70 parts PA56 resin, 10-28 parts copolyamide, 10-40 parts glass fiber, 0.2-0.4 parts lubricant, and 0.5-0.8 parts additives. In particular, when the amount of each raw material is within this range, the compatibility and performance of each component are better.

[0026] Preferably, the weight of the copolyamide is 10-50% of the total weight of the copolyamide and PA56 resin, for example, it can be 10%, 20%, 30%, 40%, 50%, or any two of these values. The inventors of this invention have found that when the weight of the copolyamide is 10-50% of the total weight of the copolyamide and PA56 resin, it can better induce nucleation, more effectively increase the crystallization temperature, shorten the cooling time, and accelerate the molding cycle. If the proportion of the copolyamide is too low, the improvement in inducing nucleation is not obvious. If the proportion of the copolyamide is too high, it is easy to cause a decrease in the fluidity of the composite material, which will also lead to a decrease in the effect.

[0027] Preferably, the number average molecular weight of the copolyamide is 10,000 to 60,000, for example, it can be a range of 10,000, 20,000, 30,000, 40,000, 50,000, 60,000 or any two of these values.

[0028] Preferably, the number average molecular weight of the copolyamide is 20,000 to 50,000.

[0029] In this invention, the number-average molecular weight of the copolyamide is obtained by gel permeation chromatography.

[0030] This invention further enhances the induction effect by controlling the number-average molecular weight of the copolyamide, which can more effectively improve the crystallization temperature, shorten the cooling time, and accelerate the molding cycle.

[0031] Preferably, the copolyamide is obtained by reacting adipic acid, hexamethylenediamine, and 1,4-cyclohexyldicarboxylic acid;

[0032] The molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is (1-5):(5-9).

[0033] The total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid is in a molar ratio of 1:1 to hexamethylenediamine.

[0034] Preferably, the 1,4-cyclohexyldicarboxylic acid includes cis-1,4-cyclohexyldicarboxylic acid and trans-1,4-cyclohexyldicarboxylic acid;

[0035] The trans-1,4-cyclohexanedicarboxylic acid accounts for ≥60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid.

[0036] This invention controls the molar ratio of each synthetic monomer and the content of trans-1,4-cyclohexanedicarboxylic acid, so that the copolyamide can promote the crystallization of PA56 at the molecular level, play a good role in inducing nucleation, effectively increase the crystallization temperature, shorten the cooling time, and accelerate the molding cycle.

[0037] It should be noted that the present invention is not limited to the synthesis method of the copolyamide, and those skilled in the art know how to synthesize the copolyamide of the present invention based on the monomer molar ratio disclosed in the present invention.

[0038] Specifically, the preparation method of the copolyamide is as follows: hexamethylenediamine and adipic acid are dissolved in deionized water, mixed evenly, and reacted to obtain copolyamide 66 salt. 1,4-cyclohexyldicarboxylic acid is mixed evenly with copolyamide 66 salt, added to a polymerization reactor, and the pH value is adjusted to neutral. The reactor is sealed, evacuated, and filled with nitrogen gas, and the air inside the reactor is exhausted. Prepolymerization is carried out at 180-220℃ and 1.2-1.8MPa pressure for 1-10 hours. The temperature is raised to 270-280℃, the pressure is released to 2-3Kpa, and the reaction is carried out for 2-6 hours to obtain the copolyamide.

[0039] Preferably, the terminal amino content of the PA56 resin is ≤92mmol / kg.

[0040] Preferably, the terminal amino content of the PA56 resin is ≤60mmol / kg. By controlling the terminal amino content of the PA56 resin, the molding cycle can be further shortened.

[0041] Preferably, the terminal amino content of the PA56 resin is ≤52mmol / kg.

[0042] Preferably, the terminal amino content of the PA56 resin is 45-52 mmol / kg, for example, it can be 45 mmol / kg, 46 mmol / kg, 48 mmol / kg, 50 mmol / kg, 52 mmol / kg or any two of these values.

[0043] Preferably, the relative viscosity of the PA56 resin is 2.0 to 3.2, for example, it can be a range of 2.0, 2.2, 2.5, 2.8, 3.0, 3.2 or any two of these values.

[0044] In this invention, the content of terminal carboxyl groups in PA56 resin is determined by titrating with a fully automatic potentiometric titrator. Specifically, 0.5g of high-temperature nylon prepolymer is taken, 50mL of o-cresol is added, the mixture is refluxed to dissolve, and after cooling, 400μL of formaldehyde solution is quickly added. The content of terminal carboxyl groups is then titrated with a standardized KOH-ethanol solution.

[0045] The relative viscosity of the PA56 resin described in this invention was tested according to the testing standard ISO307-2010. Specific test parameters included: measuring the relative viscosity η of a nylon prepolymer with a concentration of 0.25 g / dl in 98% concentrated sulfuric acid at 25 ± 0.01℃. r .

[0046] Preferably, the glass fiber has an average diameter ≤13μm and an average length ≤5mm.

[0047] Preferably, the glass fiber has an average diameter of 7–13 μm and an average length of 1.5–5 mm.

[0048] Preferably, the lubricant is a carboxyl-terminated hyperbranched polyester, and the carboxyl content of the carboxyl-terminated hyperbranched polyester is 4 to 48 groups / mol, for example, it can be 16 groups / mol, 18 groups / mol, 20 groups / mol, 25 groups / mol, 30 groups / mol, 32 groups / mol or any two of these values. By using a carboxyl-terminated hyperbranched polyester and controlling its carboxyl content, the crystallization ability can be further improved, thereby further shortening the cooling time and accelerating the molding cycle.

[0049] Preferably, the lubricant is a carboxyl-terminated hyperbranched polyester, and the carboxyl content of the carboxyl-terminated hyperbranched polyester is 16 to 32 per mol.

[0050] Preferably, the terminal carboxyl hyperbranched polyester has a molecular weight of 2100–13200 g / mol and an acid value of 120–300 mg KOH / g.

[0051] Preferably, the additives include at least one of heat stabilizers, antioxidants, flame retardants, fillers, ultraviolet absorbers, and antistatic agents.

[0052] The PA56 composite material of the present invention may include heat stabilizers, and suitable heat stabilizers include, but are not limited to, phenolic heat stabilizers, amine heat stabilizers, phosphite heat stabilizers, acryloyl functional group and thioester complex heat stabilizers, calixarene heat stabilizers and combinations thereof.

[0053] The PA56 composite material of the present invention may include antioxidants, and suitable antioxidants include, but are not limited to, thioether antioxidants, polyaromatic amine antioxidants, hindered amine antioxidants, and combinations thereof.

[0054] The PA56 composite material of the present invention may include flame retardants, and suitable flame retardants include, but are not limited to, brominated polymers (e.g., brominated polystyrene), metal dialkyl phosphites (e.g., tris(diethylphosphite)aluminum), metal hydroxides (e.g., magnesium hydroxide), aromatic phosphates (e.g., resorcinol di(diphenyl phosphate) and bisphenol A di(diphenyl phosphate)), and combinations thereof.

[0055] The PA56 composite material of the present invention may include fillers, and suitable fillers include, but are not limited to, silica, calcium carbonate, talc, wollastonite, glass beads, kaolin, single crystal fiber, carbon fiber, glass fiber, barium sulfate, and combinations thereof.

[0056] The PA56 composite material of the present invention may include ultraviolet light absorbers, and suitable ultraviolet light absorbers include, but are not limited to, hydroxybenzophenones, hydroxybenzotriazoles, hydroxybenzotriazines, cyanoacrylates, nanoscale inorganic materials (e.g., titanium oxide, cerium oxide, and zinc oxide), and combinations thereof.

[0057] The PA56 composite material of the present invention may include an antistatic agent, and suitable antistatic agents include, but are not limited to, zinc oxide, manganese dioxide, chromium trioxide, and combinations thereof.

[0058] This invention also provides a method for preparing PA56 composite material, comprising the following steps:

[0059] The components are mixed evenly and then extruded and granulated using a twin-screw extruder to obtain the PA56 composite material.

[0060] Preferably, the temperature of the twin-screw extruder is set to 220–280°C, for example, it can be 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C or any two of these values.

[0061] Preferably, the screw speed of the twin-screw extruder is 200 to 800 rpm, for example, it can be 200 rpm, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm or any two of these values.

[0062] This invention also provides an application of 56 composite material in the preparation of automotive cable ties and pipe materials.

[0063] The beneficial effects of the present invention are as follows: (1) The PA56 composite material of the present invention has excellent impact strength, high crystallization temperature and short cooling time, which can realize rapid molding. The PA56 composite material can be widely used in fields with high requirements for cooling cycle. (2) The copolyamide of the present invention is combined with PA56 in the above-mentioned specific weight parts, which can play a role in inducing nucleation, effectively increasing the crystallization temperature, shortening the cooling time, and accelerating the molding cycle. It achieves the effect of promoting crystallization from the molecular structure, avoiding the technical drawbacks of the material being too brittle due to the addition of nucleating agents in the past. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0065] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0066] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0067] The raw materials used in the examples and comparative examples are described below:

[0068] PA56-1: Terminal amino content is 52 mmol / kg, relative viscosity is 2.8, Kaisai Biotechnology, brand name: E-1273.

[0069] PA56-2: Terminal amino content is 45 mmol / kg, relative viscosity is 2.6, Kaisai Biotechnology, brand name: E-2260.

[0070] PA56-3: Terminal amino content 91 mmol / kg, relative viscosity 2.8, Kaisai Biotechnology, brand name: E-1273NH.

[0071] PA66: Relative viscosity is 2.8, Zhejiang Huafeng, grade: PA66 EP-158.

[0072] Fiberglass: average diameter 10um, average length 3mm, Chongqing Composite Materials, grade: ECS301HP-03-H.

[0073] Carboxyl-terminated hyperbranched polyester-1 (hereinafter referred to as CHBP-1): Carboxyl content is 16 groups / mol, Wuhan hyperbranched, grade: C403.

[0074] Carboxyl-terminated hyperbranched polyester-2 (hereinafter referred to as CHBP-2): Carboxyl content is 32 groups / mol, Wuhan hyperbranched, grade: C404.

[0075] Carboxyl-terminated hyperbranched polyester-3 (hereinafter referred to as CHBP-3): Carboxyl content is 4 groups / mol, Wuhan hyperbranched, grade: C401.

[0076] Carboxyl-terminated hyperbranched polyester-4 (hereinafter referred to as CHBP-4): Carboxyl content is 48 groups / mol, Wuhan hyperbranched, grade: C304.

[0077] The molecular structure information of each end-carboxyl hyperbranched polyester, other than the end-carboxyl group, such as molecular weight, has a relatively constant impact on the flowability and thermal stability of the raw materials, so it will not be discussed in detail here.

[0078] Additives: Antioxidant 1010 and Antioxidant 264 are compounded in a weight ratio of 1:1.

[0079] Copolymer polyamide-1:35000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio (m / n, the same below) of the 1,4-cyclohexyldicarboxylic acid and adipic acid is 3:7, and the molar ratio of the total molar amount of the 1,4-cyclohexyldicarboxylic acid and adipic acid to the hexamethylenediamine is 1:1.

[0080] Copolymer polyamide-2: 35000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 1:9, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0081] Copolymer polyamide-3: 35000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 5:5, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0082] The copolyamide-4:10000 contains trans-1,4-cyclohexanedicarboxylic acid, which accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid. The molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 3:7, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0083] Copolymer polyamide-5:60000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 3:7, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0084] Copolymer polyamide-6: 35000, trans-1,4-cyclohexanedicarboxylic acid accounts for 40% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 3:7, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0085] Copolymer polyamide-7:70000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 3:7, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0086] The copolyamide-8:8000 contains trans-1,4-cyclohexanedicarboxylic acid, which accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid. The molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 3:7, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0087] Copolymer polyamide-9:35000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 6:4, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0088] Copolymer polyamide-10: 35000, trans-1,4-cyclohexanedicarboxylic acid accounts for 60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid, the molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is 0.5:9.5, and the molar ratio of the total molar amount of 1,4-cyclohexyldicarboxylic acid and adipic acid to hexamethylenediamine is 1:1.

[0089] The preparation methods of the aforementioned copolyamides 1 to 10 all include the following steps:

[0090] Hexamethylenediamine and adipic acid were dissolved in deionized water and mixed thoroughly at 60°C to form a concentrated solution. The pH was adjusted to 7.2, and the reaction was allowed to proceed for 2 hours. After cooling and crystallization, vacuum filtration, washing, and drying, copolymer 66 salt was obtained. 1,4-cyclohexyldicarboxylic acid was thoroughly mixed with copolymer 66 salt and added to a polymerization reactor, with the pH adjusted to neutral. The reactor was sealed, evacuated, and purged with nitrogen. The reaction system was heated to 190°C and prepolymerized at 1.5 MPa for 1–10 hours. The temperature was then slowly increased to 275°C, and the pressure was continuously released to 2.7 kPa to complete the polymerization reaction for 2–6 hours. After cooling and pelletizing, the copolymer polyamide was obtained.

[0091] By adjusting the feed ratio of 1,4-cyclohexyldicarboxylic acid and adipic acid, as well as the trans / cis conformation ratio in 1,4-cyclohexyldicarboxylic acid, copolyamides with different structures were obtained. By adjusting the degree of polymerization through polymerization time, copolyamides with different molecular weights were obtained.

[0092] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0093] Examples 1-18, Comparative Examples 1-4

[0094] The formulations of PA56 composite materials in Examples 1-18 and Comparative Examples 1-4 are shown in Tables 1 and 2 (all figures are parts by weight).

[0095] The preparation methods of the PA56 composite materials in Examples 1-18 and Comparative Examples 1-4 all include the following steps:

[0096] The components are mixed evenly and then extruded and granulated through a twin-screw extruder to obtain PA56 composite material. The twin-screw extruder is set with a temperature of 220-280℃ and a screw speed of 400 rpm.

[0097] Table 1

[0098]

[0099] Table 2

[0100]

[0101]

[0102] Performance testing

[0103] Crystallization peak temperature: The instrument used was a TQ 2000 analyzer from TA Instruments (USA). Under nitrogen protection, the sample was heated from 30°C to 300°C at a rate of 10°C / min, held at 300°C for 5 minutes, and then cooled to 30°C at a rate of 10°C / min. A higher crystallization temperature allows the part to reach the crystallization temperature and solidify more quickly during injection molding and cooling.

[0104] Notched impact strength: Cantilever beam notched impact strength (Type A notch): according to ISO 180-2000, 4mm, 23℃.

[0105] Table 3

[0106]

[0107]

[0108] As can be seen from Table 3, the PA56 composite material of this invention has excellent impact strength, high crystallization temperature, and short cooling time, enabling rapid molding. The crystallization peak temperature of the PA56 composite material of this invention is 202–215℃, the cooling time is 15–28 s, and the notched impact strength is 9.5–13.5 kJ / m. 2 .

[0109] Comparative Examples 1-4 show that by controlling the weight parts of each raw material to: 50-70 parts PA56 resin, 10-28 parts copolyamide, 10-40 parts glass fiber, 0.2-0.4 parts lubricant, and 0.5-0.8 parts additives, the crystallization peak temperature and notched impact strength are further improved.

[0110] Comparative examples 4-6 show that by controlling the weight of the copolyamide to be 10-50% of the total weight of the copolyamide and PA56 resin, the crystallization peak temperature and notched impact strength are further improved.

[0111] Comparing Examples 4, 7, and 8, it can be seen that by using PA56 resin with a terminal amino content ≤60mmol / kg, the crystallization peak temperature and notched impact strength were further improved.

[0112] Comparing Examples 1, 4, 5, 17, and 18, it can be seen that by using copolyamides with a molecular weight of 10,000 to 50,000, the crystallization peak temperature and notched impact strength were further improved.

[0113] Comparing Examples 4 and 13, it can be seen that by controlling the molar percentage of trans-1,4-cyclohexanedicarboxylic acid in the total 1,4-cyclohexyldicarboxylic acid to be ≥60%, the crystallization peak temperature and notched impact strength are further improved.

[0114] Compared with Examples 4 and 14-16, by using end-carboxyl hyperbranched polyester as a lubricant and controlling the carboxyl content of the end-carboxyl hyperbranched polyester to be 16-32 groups / mol, the crystallization peak temperature and notched impact strength were further improved.

[0115] As can be seen from the comparison of Example 4 with Comparative Examples 1 and 2, the copolyamide of the present invention can significantly improve the crystallization peak temperature and notched impact strength.

[0116] Comparing Examples 4, 9, 10 and Comparative Examples 3-4, it can be seen that when the proportion of 1,4-cyclohexyldicarboxylic acid in the copolyamide of the present invention is too low, it will lead to poor impact resistance, and when the proportion of 1,4-cyclohexyldicarboxylic acid is too high, it will lead to a longer cooling time.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A PA56 composite material, characterized in that, It includes the following components in parts by weight: 28-82 parts PA56 resin, 2.8-42 parts copolyamide, 1-50 parts glass fiber, 0.09-0.6 parts lubricant, and 0.2-2 parts additives; The structural formula of the copolyamide is shown in Formula I: Formula I In Formula I, m / n = (1~5): (5~9); The PA56 resin has an end-amino group content ≤60mmol / kg; the lubricant is a carboxyl-terminated hyperbranched polyester, and the carboxyl group content of the carboxyl-terminated hyperbranched polyester is 16~32 groups / mol. The weight of the copolyamide is 10-50% of the total weight of the copolyamide and PA56 resin; The copolyamide is obtained by reacting adipic acid, hexamethylenediamine, and 1,4-cyclohexyldicarboxylic acid. The 1,4-cyclohexyldicarboxylic acid includes cis-1,4-cyclohexyldicarboxylic acid and trans-1,4-cyclohexyldicarboxylic acid; The trans-1,4-cyclohexanedicarboxylic acid accounts for ≥60% of the total molar percentage of 1,4-cyclohexyldicarboxylic acid; The additives include at least one of the following: heat stabilizers, antioxidants, flame retardants, ultraviolet absorbers, and antistatic agents.

2. The PA56 composite material according to claim 1, characterized in that, The number average molecular weight of the copolyamide is 10,000 to 60,000.

3. The PA56 composite material according to claim 1, characterized in that, The molar ratio of 1,4-cyclohexyldicarboxylic acid to adipic acid is (1~5):(5~9).

4. The PA56 composite material according to claim 1, characterized in that, The glass fiber has an average diameter of ≤13μm and an average length of ≤5mm.

5. The method for preparing the PA56 composite material according to any one of claims 1 to 4, characterized in that, Includes the following steps: The components are mixed evenly and then extruded and granulated using a twin-screw extruder to obtain the PA56 composite material.

6. The application of the PA56 composite material according to any one of claims 1 to 4 in the preparation of automotive cable ties and pipe materials.

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