High-ductility polyamide material as well as preparation method and application thereof

Abstract

The invention relates to a high-ductility polyamide material as well as a preparation method and application thereof, and belongs to the technical field of compositions of high-molecular compounds. The high-ductility polyamide material disclosed by the invention is prepared from the following components in parts by weight: 93 to 99.5 parts of polyamide resin, 0.1 to 1 part of a tackifier A, 0.1 to 1 part of a tackifier B and 0.1 to 2 parts of a lubricant, the tackifier A is an ethylene-maleic anhydride copolymer of which the weight-average molecular weight is less than or equal to 18000 g / mol, and the tackifier B is an ethylene-maleic anhydride copolymer of which the weight-average molecular weight is more than or equal to 50000 g / mol; the lubricant at least comprises polytetrafluoroethylene. The polyamide material has excellent processing ductility and uniformity.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer compound compositions, and in particular to a high-ductility polyamide material and a preparation method and application thereof. Background Art

[0002] Polyamide, also known as nylon, is a polymer formed by the ring-opening polymerization of lactam or the condensation of diamine and dibasic acid. It mainly includes aliphatic polyamide, semi-aromatic polyamide and aromatic polyamide. Plastic parts made of polyamide are widely used in transportation, electronics and electrical, packaging and other fields. The processing methods of polyamide mainly include injection molding, extrusion, die casting, rotational molding, etc., among which extrusion is the most commonly used processing method for polyamide pipes or sheets. Taking polyamide pipes as an example, it is generally necessary to first dry the polyamide raw material and add it to the extruder to process it to a molten state, and then form a tube blank through a mold, and then the tube blank is pulled and stretched, cooled and shaped, and cut to obtain a polyamide pipe. In the industrial production of polyamide pipes or sheets, the production efficiency is generally ensured by increasing the pulling rate in the pulling and stretching step, but in actual application, it is found that the processing ductility of polyamide materials is poor, which easily leads to poor surface integrity of polyamide pipes or sheets or even rupture, and it is difficult to meet the production needs of polyamide pipes or sheets. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a high-ductility polyamide material and a preparation method and application thereof.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] In a first aspect, the present invention provides a high ductility polyamide material, comprising the following components by weight:

[0006] Polyamide resin is 93-99.5 parts, tackifier A is 0.1-1 parts, tackifier B is 0.1-1 parts, and lubricant is 0.1-2 parts;

[0007] The tackifier A is an ethylene-maleic anhydride copolymer with a weight average molecular weight of ≤18000 g / mol;

[0008] The tackifier B is an ethylene-maleic anhydride copolymer having a weight average molecular weight of ≥50000 g / mol;

[0009] The lubricant includes at least polytetrafluoroethylene.

[0010] The present invention uses an ethylene-maleic anhydride copolymer with a weight average molecular weight of ≤18000 g / mol as a tackifier A, and uses an ethylene-maleic anhydride copolymer with a weight average molecular weight of ≥50000 g / mol as a tackifier B, and combines the two to interact with the polyamide resin, wherein the high molecular weight tackifier mainly plays a skeleton support role, while the low molecular weight tackifier has better dispersibility and can significantly improve the uniformity of the finished product; and at the same time, a specific lubricant is used to further enhance the dispersing effect of the tackifier in the polyamide molecular system, thereby effectively improving the ductility of the polyamide material in the extrusion process, and improving the uniformity of the product.

[0011] Among them, the mass fraction of the polyamide resin in the high ductility polyamide material is preferably greater than or equal to 80%, and the viscosity of the polyamide resin is 100-300 mL / g, which can be obtained by ISO 307-2019 test; the weight average molecular weight of the ethylene-maleic anhydride copolymer can be measured by gel permeation chromatography (GPC).

[0012] In addition, the mass content of maleic anhydride in the above ethylene-maleic anhydride copolymer is greater than 70%, preferably an ethylene-maleic anhydride alternating copolymer with a molar ratio of ethylene to maleic anhydride of about 1: 1. It should also be noted that the mass proportion of polytetrafluoroethylene in the above lubricant is greater than or equal to 4.5%, preferably greater than or equal to 50%, specifically 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%.

[0013] Optionally, the weight proportion of the polyamide resin in the above-mentioned high ductility polyamide material can be 93.5 parts, 94 parts, 94.5 parts, 95 parts, 95.5 parts, 96 parts, 96.5 parts, 97 parts, 97.5 parts, 98 parts, 98.5 parts, and 99 parts; the weight proportion of the tackifier A can be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, and 0.9 parts; the weight proportion of the tackifier B can be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, and 0.9 parts; the weight proportion of the lubricant can be 0.3 parts, 0.5 parts, 0.7 parts, 0.9 parts, 1.1 parts, 1.3 parts, 1.5 parts, 1.7 parts, and 1.9 parts.

[0014] As a preferred embodiment of the high ductility polyamide material of the present invention, the high ductility polyamide material comprises the following components in parts by weight: 95 to 98 parts of polyamide resin, 0.3 to 0.7 parts of tackifier A, 0.3 to 0.7 parts of tackifier B, and 0.4 to 1.3 parts of lubricant.

[0015] As a preferred embodiment of the high ductility polyamide material of the present invention, the mass ratio of the tackifier A to the tackifier B is 1:(0.5-1.2). Optionally, the mass ratio of the tackifier A to the tackifier B can be 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1. When the mass ratio of tackifier A to tackifier B is within the above ratio range, the skeleton support effect of tackifier A and the dispersing effect of tackifier B can be better exerted at the same time, so that the combination of the two can significantly improve the processing ductility and uniformity of the polyamide material.

[0016] As a preferred embodiment of the high ductility polyamide material of the present invention, the weight average molecular weight of the tackifier A is 9000 g / mol to 16000 g / mol, more preferably 10000 g / mol to 15000 g / mol; specifically, it can be 3000 g / mol, 50000 g / mol, 70000 g / mol, 11000 g / mol, 12000 g / mol, 13000 g / mol, or 14000 g / mol.

[0017] As a preferred embodiment of the high ductility polyamide material of the present invention, the weight average molecular weight of the tackifier B is 55000 g / mol to 90000 g / mol, and more preferably 60000 to 80000 g / mol; specifically, it can be 62000 g / mol, 64000 g / mol, 66000 g / mol, 68000 g / mol, 70000 g / mol, 72000 g / mol, 74000 g / mol, 76000 g / mol, 78000 g / mol, 82000 g / mol, 85000 g / mol, or 95000 g / mol.

[0018] As a preferred embodiment of the high ductility polyamide material of the present invention, the lubricant further comprises at least one of silicone, stearic acid and its salts, hyperbranched polyester, aliphatic fatty acid ester, and ethylene-acrylic acid copolymer.

[0019] As a preferred embodiment of the high ductility polyamide material of the present invention, the components of the high ductility polyamide material further include 0 to 2 parts by weight of an antioxidant; the antioxidant is preferably at least one of a hindered phenol antioxidant, a hindered amine antioxidant, and a phosphorus-containing antioxidant. Optionally, the weight percentage of the antioxidant can be 0.1 parts, 0.2 parts, 0.4 parts, 0.6 parts, 0.8 parts, 1 parts, 1.2 parts, 1.4 parts, 1.6 parts, and 1.8 parts.

[0020] In addition, the high ductility polyamide material of the present invention may further comprise 0 to 30 parts by weight of a functional additive, wherein the functional additive is one or more of a flame retardant, a toughening agent, a weathering agent, and a color powder. Optionally, the weight proportion of the functional additive may be 0.1 parts, 0.2 parts, 0.5 parts, 1 parts, 3 parts, 5 parts, 7 parts, 9 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 27 parts, or 29 parts.

[0021] The weight proportion of the flame retardant is 10 to 30 parts, preferably at least one of a halogen-containing flame retardant, a hypophosphite flame retardant, and a melamine cyanurate flame retardant; the halogen-containing flame retardant is a brominated polymer flame retardant, preferably one or more of brominated polystyrene, brominated epoxy resin, and brominated polycarbonate.

[0022] The weight proportion of the toughening agent is 1 to 30 parts, and is preferably at least one of maleic anhydride grafted POE, POE, EPDM, and SEBS.

[0023] As a preferred embodiment of the high ductility polyamide material of the present invention, the polyamide resin is at least one of PA6, PA11, PA12, PA46, PA56, PA66, PA610, PA612, PA6T, PA9T, PA10T, PA1010, and PA1012.

[0024] In a second aspect, the present invention provides a method for preparing the above-mentioned high-ductility polyamide material, comprising the following steps: mixing the components uniformly and then melt-extruding to obtain the high-ductility polyamide material.

[0025] Specifically, in the above preparation method, a twin-screw extruder can be used for melt extrusion, the temperature of melt extrusion is 220-260° C., and the screw speed of the twin-screw extruder is 300-500 rpm.

[0026] In a third aspect, the present invention provides use of the above-mentioned high-ductility polyamide material in the preparation of polyamide pipes or sheets.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention uses ethylene-maleic anhydride copolymers with specific molecular weights as tackifier A and tackifier B respectively, and combines the two to interact with polyamide resin, and simultaneously uses a specific lubricant, thereby effectively improving the ductility of the polyamide material during extrusion processing and improving the uniformity of the product. DETAILED DESCRIPTION

[0029] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0030] Unless otherwise specified, other materials, reagents, etc. used in the examples and comparative examples can be obtained from commercial sources.

[0031] 1. Raw materials and reagents

[0032] Polyamide resin 1 is PA6, brand BL40H, manufactured by Baling Petrochemical;

[0033] Polyamide resin 2 is PA66, brand EP-158, manufacturer is Huafeng;

[0034] Polyamide resin 3 is PA610, brand F150, manufactured by Guangyin;

[0035] Tackifier A1 is an ethylene-maleic anhydride copolymer with a weight average molecular weight of 10,000 g / mol, brand E10P, and manufactured by Shanghai Nanosu Alloy Technology;

[0036] Tackifier A2 is an ethylene-maleic anhydride copolymer with a weight average molecular weight of 15000 g / mol, with a brand name of E15P, and the manufacturer is Shanghai Nanosu Alloy Technology;

[0037] Tackifier B1 is an ethylene-maleic anhydride copolymer with a weight average molecular weight of 60,000 g / mol, brand E60P, and manufactured by Shanghai Nanosu Alloy Technology;

[0038] Tackifier B2 is an ethylene-maleic anhydride copolymer with a weight average molecular weight of 80,000 g / mol, brand E80P, and manufactured by Shanghai Nanosu Alloy Technology;

[0039] Thickener C1 is an ethylene-maleic anhydride copolymer with a weight average molecular weight of 25,000 g / mol, brand E25P, and manufactured by Shanghai Nanosu Alloy Technology;

[0040] Tackifier C2 is styrene-glycidyl methacrylate, brand ADR 4380, manufacturer BASF;

[0041] Lubricant 1 is ethylene-acrylic acid copolymer, brand A-C540A, manufactured by Honeywell;

[0042] Lubricant 2 is polytetrafluoroethylene, brand GR-C525, manufacturer is Zhejiang Ge Rui;

[0043] Lubricant 3 is silicone, brand MB50-002, manufacturer Dow Corning;

[0044] Lubricant 4 is polytetrafluoroethylene, brand F-5AEX, manufactured by Solvay;

[0045] Antioxidant, brand name IRGANOX 1098, manufacturer BASF;

[0046] The toughening agent is maleic anhydride grafted POE, brand N493, manufacturer is BASF;

[0047] The flame retardant is brominated polystyrene, the brand is SAYTEX HP-5010, and the manufacturer is Albemarle.

[0048] 2. Preparation method of high ductility polyamide material of the present invention

[0049] According to the formula, the components are mixed evenly and then added into a twin-screw extruder for melt extrusion to obtain a high-ductility polyamide material; wherein the melt extrusion temperature is 220-260° C., and the screw speed of the twin-screw extruder is 300-500 rpm.

[0050] Table 1 Weight fractions of each component of high ductility polyamide material in Examples 1 to 12

[0051] Example 1 2 3 4 5 6 7 8 9 10 11 12 Polyamide resin 1 96.8 / / 96.8 96.8 96.8 96.8 96.8 96.8 96.8 93 99.5 Polyamide resin 2 / 96.8 / / / / / / / / / / Polyamide resin 3 / / 96.8 / / / / / / / / / Thickener A1 0.5 0.5 0.5 / 0.5 / 0.5 0.67 0.33 0.7 1 0.1 Thickener A2 / / / 0.5 / 0.5 / / / / / / Thickener B1 0.5 0.5 0.5 0.5 / / 0.5 0.33 0.67 0.7 0.1 1 Thickener B2 / / / / 0.5 0.5 / / / / / / Lubricant 1 0.5 0.5 0.5 0.5 0.5 0.5 0 0.5 0.5 0.5 1 0.05 Lubricant 2 0.5 0.5 0.5 0.5 0.5 0.5 1 0.5 0.5 0.5 0.05 1 Antioxidants 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 1 0.1

[0052] Table 2 Weight fractions of each component of high ductility polyamide material in Examples 13 to 16 and Comparative Examples 1 to 6

[0053]

[0054]

[0055] 3. Performance testing

[0056] 1) Processing ductility: The high ductility polyamide materials in the embodiments and comparative examples were dried at 120° C. for 4 to 6 hours, and then added to a single screw extruder to extrude a sheet. The width of the die head used was 100 mm and the thickness was 0.2 mm. While keeping the other parameters unchanged, the pulling speed was gradually increased to observe the integrity of the surface of the extruded sheet. The processing ductility of the polyamide material was evaluated based on the maximum pulling speed when continuous extrusion was possible and the surface of the extruded sheet was intact. The larger the maximum pulling speed, the better the processing ductility of the polyamide material during extrusion.

[0057] 2) Uniformity: The high ductility polyamide materials in the embodiments and comparative examples were dried at 120° C. for 4 to 6 hours and then added to a single screw extruder to extrude sheets; a sheet sample with a length of 100 mm, a width of 100 mm and a thickness of 0.2 mm was then divided into 9 areas at uniform intervals, and the transmittance of each area was tested (the test standard is GB / T 2410-2008); then the difference between the maximum and minimum transmittances in the 9 areas was used as an indicator for evaluating the uniformity of the extruded sample, and the smaller the value of the indicator, the better the uniformity of the sample.

[0058] Table 3 Properties of high ductility polyamide materials in various embodiments and comparative examples

[0059]

[0060]

[0061] According to the data in Table 3, the maximum pulling speed of the polyamide material in Examples 1 to 16 is greater than 10.5 m / min, reaching 10.9 to 12.9 m / min, and the difference between the maximum and minimum values ​​of the transmittance is less than or equal to 1%, indicating that the polyamide material of the present invention not only has excellent ductility, but also the obtained product has good uniformity. According to Comparative Examples 1, 2 and 5, it can be seen that the addition of tackifier A or B alone has a similar effect to the addition of conventional polyamide tackifiers (styrene-glycidyl methacrylate), and it is difficult to effectively improve the processing ductility and uniformity of polyamide materials; at the same time, combined with the data of Comparative Examples 3 and 4, it can be further found that compared with the addition of tackifier A or B alone, when tackifier C is compounded with tackifier A or B, although the processing ductility of polyamide materials can be improved to a certain extent, the degree of improvement is extremely limited, which fully illustrates that it is not the simple combination of ethylene-maleic anhydride copolymers with different weight average molecular weights that can effectively improve the processing ductility of polyamide materials, but it is necessary to compound ethylene-maleic anhydride copolymers with specific weight average molecular weights to significantly improve the processing ductility of polyamide materials. In addition, according to the data of Comparative Example 6, it can be seen that in addition to tackifiers, the type of lubricant also has an important influence on the processing ductility and uniformity of polyamide materials. Compared with other types of lubricants, polytetrafluoroethylene plays a key role in improving the processing ductility and uniformity of polyamide materials.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A high ductility polyamide material, characterized in that: By weight, it includes the following components: Polyamide resin is 93-99.5 parts, tackifier A is 0.1-1 parts, tackifier B is 0.1-1 parts, and lubricant is 0.1-2 parts; The tackifier A is an ethylene-maleic anhydride copolymer with a weight average molecular weight of ≤18000 g / mol; The tackifier B is an ethylene-maleic anhydride copolymer having a weight average molecular weight of ≥50000 g / mol; The lubricant includes at least polytetrafluoroethylene.

2. The high ductility polyamide material according to claim 1, characterized in that: The high-ductility polyamide material comprises the following components in parts by weight: 95 to 98 parts of polyamide resin, 0.3 to 0.7 parts of tackifier A, 0.3 to 0.7 parts of tackifier B, and 0.4 to 1.3 parts of lubricant.

3. The high ductility polyamide material according to claim 1, characterized in that: The mass ratio of the tackifier A to the tackifier B is 1:(0.5-2).

4. The high ductility polyamide material according to claim 1, characterized in that: The weight average molecular weight of the tackifier A is 9000 to 16000 g / mol.

5. The high ductility polyamide material according to claim 1, characterized in that: The weight average molecular weight of the tackifier B is 55000 to 90000 g / mol.

6. The high ductility polyamide material according to claim 1, characterized in that: The lubricant further comprises at least one of silicone, stearic acid and its salt, hyperbranched polyester, aliphatic fatty acid ester, and ethylene-acrylic acid copolymer.

7. The high ductility polyamide material according to claim 1, characterized in that: The components of the high-ductility polyamide material also include 0 to 1 parts by weight of an antioxidant; and / or 0 to 30 parts by weight of a functional additive.

8. The high ductility polyamide material according to any one of claims 1 to 7, characterized in that: The polyamide resin is at least one of PA6, PA11, PA12, PA46, PA56, PA66, PA610, PA612, PA6T, PA9T, PA10T, PA1010, and PA1012.

9. The method for preparing the high ductility polyamide material according to any one of claims 1 to 8, characterized in that: The following steps are involved: The components are mixed evenly and then melt-extruded to obtain a highly ductile polyamide material.

10. Use of the high ductility polyamide material according to any one of claims 1 to 8 in the preparation of polyamide pipes or sheets.

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