Polyamide composite material, method for producing same, and use thereof

Abstract

The present application relates to a kind of polyamide composite and its preparation method and application, belong to the composition technical field of polymer compound.The polyamide composite of the present application includes the following weight parts of component: polyamide 94~99.7 parts, tackifier 0.2~4 parts, processing aid 0.1~2 parts;The tackifier includes methyl vinyl ether-maleic anhydride copolymer and polytetrafluoroethylene.The polyamide composite has good processing ductility, can make the product prepared have excellent uniformity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high molecular compound composition, in particular to a polyamide composite material and a preparation method and application thereof. BACKGROUND

[0002] Polyamide (also known as nylon) is a thermoplastic polymer, which contains amido (-CO-NH-) repeating structural units in the main chain. Due to its high crystallinity, obvious melting point, large surface hardness, wear resistance, small friction coefficient, self-lubricating property, shock absorption and noise reduction, it is widely used in transportation, electronics and electrical, packaging and other fields. At present, polyamide mainly includes aliphatic polyamide, semi-aromatic polyamide and aromatic polyamide, which can be processed and manufactured by injection molding, extrusion, die casting, rotational molding and other processes. Among them, extrusion is the most commonly used processing method for polyamide pipes or sheets. For example, the common production process of polyamide pipe is to dry the polyamide raw material, process it to a molten state in an extruder to form a polyamide melt, then shape the pipe blank through a mold, and then stretch the pipe blank by traction, cool and shape, and cut it to obtain a polyamide pipe. In the actual production process of polyamide pipe, the traction rate in the traction stretching step is generally increased to ensure production efficiency, which requires the polyamide melt to have good processing ductility. However, the processing ductility of the existing polyamide material is poor, which easily leads to poor surface integrity of the polyamide pipe in the high-speed production process or even rupture, and is difficult to meet the actual production needs. SUMMARY

[0003] The present application aims to overcome the shortcomings of the prior art and provide a polyamide composite material and a preparation method and application thereof.

[0004] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0005] In a first aspect, the present application provides a polyamide composite material, which comprises the following components in parts by weight: 94-99.7 parts of polyamide, 0.2-4 parts of tackifier, and 0.1-2 parts of processing aid.

[0006] The tackifier comprises methyl vinyl ether-maleic anhydride copolymer and polytetrafluoroethylene.

[0007] The present application uses methyl vinyl ether-maleic anhydride copolymer and polytetrafluoroethylene in combination as the tackifier of polyamide. The methyl vinyl ether-maleic anhydride copolymer mainly plays a bridging and crosslinking role in the polyamide resin matrix, which can improve the melt strength of the polyamide composite material and its extrusion performance. The polytetrafluoroethylene mainly promotes the uniform dispersion of the methyl vinyl ether-maleic anhydride copolymer in the polyamide. The interaction between the two can not only effectively improve the processing ductility of the polyamide composite material, but also significantly improve the uniformity of the polyamide product.

[0008] Specifically, the mass fraction of the polyamide in the polyamide composite is preferably greater than or equal to 70%; alternatively, the polyamide in the polyamide composite can specifically be one of 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, 99 parts, 99.7 parts or a range value of any two thereof; the tackifier can specifically be one of 0.2 parts, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or a range value of any two thereof; and the processing aid can specifically be one of 0.1 parts, 0.3 parts, 0.5 parts, 0.7 parts, 0.9 parts, 1.2 parts, 1.4 parts, 1.6 parts, 1.8 parts, 2 parts or a range value of any two thereof.

[0009] Alternatively, the processing aid in the polyamide composite includes but is not limited to common aids in the field of modified polyamides, such as antioxidants, lubricants, etc.; wherein the antioxidants include but are not limited to one or more of hindered phenolic antioxidants, hindered amine antioxidants, phosphorus-containing antioxidants; and the lubricants include but are not limited to one or more of stearic acid / salts, modified ethylene bis fatty acid amide, hyperbranched polyester, aliphatic fatty acid ester, ethylene-acrylic acid copolymer.

[0010] In addition, the polyamide composite of the present application can also contain 0-30 parts by weight of functional additives, which are one or more of flame retardants, toughening agents, weathering agents, toners. Alternatively, the parts by weight of the functional additives can specifically 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, 29 parts.

[0011] The parts by weight of the flame retardant are 0-30 parts, preferably at least one of halogen-containing flame retardants, hypophosphite flame retardants, melamine cyanurate flame retardants; the halogen-containing flame retardant is a brominated high molecular flame retardant, preferably one or more of brominated polystyrene, brominated epoxy resin, brominated polycarbonate.

[0012] The parts by weight of the toughening agent are 0-30 parts, preferably at least one of maleic anhydride grafted POE, POE, EPDM, SEBS.

[0013] The parts by weight of the weathering agent are 0-1 parts, and the parts by weight of the toner are 0-2 parts.

[0014] As a preferred embodiment of the polyamide composite of the present application, the polyamide composite comprises the following components by weight: polyamide 96-98 parts, tackifier 1.3-3.3 parts, processing aid 0.5-1 part.

[0015] As a preferred embodiment of the polyamide composite material of the present application, the mass ratio of the methyl vinyl ether-maleic anhydride copolymer to polytetrafluoroethylene is (0.1-1):(0.1-3), preferably (0.1-0.9):(1.4-2.2), more preferably (0.3-0.7):(1.5-2).

[0016] Optionally, the methyl vinyl ether-maleic anhydride copolymer is 0.1-1 parts by weight, and specifically can be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts; the polytetrafluoroethylene is 0.1-3 parts, and specifically can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 2.8 parts.

[0017] As a preferred embodiment of the polyamide composite material of the present application, the number average molecular weight of the methyl vinyl ether-maleic anhydride copolymer is 70000-320000 g / mol, preferably 80000-311000 g / mol. Optionally, the number average molecular weight of the methyl vinyl ether-maleic anhydride copolymer can be specifically 100000 g / mol, 150000 g / mol, 200000 g / mol, 250000 g / mol, 280000 g / mol, 310000 g / mol. The number average molecular weight of the methyl vinyl ether-maleic anhydride copolymer can be measured by gel permeation chromatography (GPC).

[0018] As a preferred embodiment of the polyamide composite material of the present application, the number average molecular weight of the polytetrafluoroethylene is 10000-50000 g / mol, preferably 12000-30000 g / mol. Optionally, the number average molecular weight of the polytetrafluoroethylene can be specifically 12000 g / mol, 15000 g / mol, 20000 g / mol, 25000 g / mol, 30000 g / mol, 35000 g / mol, 40000 g / mol, 45000 g / mol. The number average molecular weight of the polytetrafluoroethylene can be measured by gel permeation chromatography (GPC).

[0019] As a preferred embodiment of the polyamide composite material of the present application, the viscosity number of the polyamide is 100-300 mL / g; the viscosity number of the polyamide can be obtained by ISO 307-2019 test. Optionally, the viscosity number of the polyamide can be specifically 120 mL / g, 150 mL / g, 160 mL / g, 180 mL / g, 200 mL / g, 230 mL / g, 250 mL / g, 280 mL / g.

[0020] As a preferred embodiment of the polyamide composite material of the present application, the polyamide comprises at least one of PA6, PA11, PA12, PA46, PA56, PA66, PA610, PA612, PA6T, PA9T, PA10T, PA1010, and PA1012.

[0021] In a second aspect, the present application provides a preparation method of the above-mentioned polyamide composite material, comprising the following steps: uniformly mixing the components and then melt-extruding to obtain the polyamide composite material.

[0022] Specifically, in the above-mentioned preparation method, a twin-screw extruder can be used for melt-extrusion, the temperature for melt-extrusion is 210-280℃, and the screw rotation speed of the twin-screw extruder is 300-500 rpm.

[0023] In a third aspect, the present application provides an application of the above-mentioned polyamide composite material in preparing nylon filaments, nylon films, nylon pipes or sheets.

[0024] In a fourth aspect, the present application provides a nylon pipe or sheet, which comprises the above-mentioned polyamide composite material.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] In the present application, methyl vinyl ether-maleic anhydride copolymer and polytetrafluoroethylene are combined to serve as the tackifier of the polyamide, wherein the methyl vinyl ether-maleic anhydride copolymer mainly plays a bridging crosslinking role in the polyamide resin matrix, which can improve the melt strength of the polyamide composite material and improve the extrusion performance thereof; and the polytetrafluoroethylene mainly promotes the uniform dispersion of the methyl vinyl ether-maleic anhydride copolymer in the polyamide, the interaction of the two can not only effectively improve the processing ductility of the polyamide composite material, but also significantly improve the uniformity of the polyamide product. DETAILED DESCRIPTION

[0027] To better illustrate the purposes, technical solutions and advantages of the present application, the present application will be further described below in combination with specific examples.

[0028] Unless otherwise specified, the other materials, reagents, etc. used in the examples and comparative examples can be obtained from commercial channels.

[0029] 1. Raw material reagents

[0030] Polyamide-1 (PA6), brand BL40H, manufacturer Baoling Petrochemical, viscosity number 280 mL / g;

[0031] Polyamide-2 (PA66), brand EP-158, manufacturer Huafeng, viscosity number 160 mL / g;

[0032] Polyamide-3 (PA610), brand F150, manufacturer Guangyin, viscosity 150 mL / g;

[0033] Tackifier-1 is a methyl vinyl ether-maleic anhydride copolymer with a number average molecular weight of about 80000 g / mol, brand 416339, manufacturer Sigmaaldrich;

[0034] Tackifier-2 is a methyl vinyl ether-maleic anhydride copolymer with a number average molecular weight of about 311000 g / mol, brand 416320, manufacturer Sigmaaldrich;

[0035] Tackifier-3 is a ethylene-maleic anhydride copolymer with a number average molecular weight of about 80000 g / mol, brand E80, manufacturer Shanghai Naspolymer Alloy Technology;

[0036] Polytetrafluoroethylene-1, number average molecular weight about 12000 g / mol, brand GR-C525, manufacturer Zhejiang GeRu;

[0037] Polytetrafluoroethylene-2, number average molecular weight about 30000 g / mol, brand GR-C0590P, manufacturer Zhejiang GeRu;

[0038] Toughening agent is maleic anhydride grafted POE, brand N493, manufacturer BASF;

[0039] Flame retardant is brominated polystyrene, brand SAYTEX HP-5010, manufacturer Albemarle;

[0040] Antioxidant is IRGANOX 1098, lubricant is A-C540A, both are commercially available.

[0041] 2. The preparation method of the polyamide composite material of the present application

[0042] According to the formula, after mixing the components uniformly, melt extruding in a twin-screw extruder, the polyamide composite material is obtained; wherein the temperature of melt extruding is 210-280 ℃, and the screw rotation speed of the twin-screw extruder is 300-500 rpm.

[0043] Table 1 Weight parts of each component of the polyamide composite material in Examples 1-13

[0044] Example 1 2 3 4 5 6 7 8 9 10 11 12 13 Polyamide-1 97 / / 97 97 97 97 97 97 94 99.7 96 98 Polyamide-2 / 97 / / / / / / / / / / / Polyamide-3 / / 97 / / / / / / / / / / Tackifier-1 0.5 0.5 0.5 / 0.5 0.1 0.9 0.5 0.5 1 0.1 0.8 0.3 Tackifier-2 / / / 0.5 / / / / / / / Polytetrafluoroethylene-1 1.8 1.8 1.8 1.8 / 2.2 1.4 1.8 1.8 0.1 3 2.5 1 Polytetrafluoroethylene-2 / / / / 1.8 / / / / / / / / Toughener / / / / / / / 5 / / / / / Flame Retardant / / / / / / / / 10 / / / / Antioxidant 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.9 0.03 0.2 0.2 Lubricant 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 2.1 0.07 0.5 0.5

[0045] Table 2 Weight parts of each component of the polyamide composite material in Comparative Examples 1-3

[0046] Number Comparative Example 1 Comparative Example 2 Comparative Example 3 Polyamide-1 97 97 97 Tackifier-1 / 2.3 / Tackifier-3 0.5 / / Polytetrafluoroethylene-1 1.8 / 2.3 Antioxidant 0.2 0.2 0.2 Lubricant 0.5 0.5 0.5

[0047] 3. Performance test

[0048] 1) Processing ductility: The polyamide composites in each example and comparative example were dried at 100-120°C for 4-6 hours and then extruded into sheets in a single-screw extruder. The width of the die head used was 60 mm and the thickness was 0.15 mm. With other parameters kept constant, the traction speed was gradually increased to observe the integrity of the surface of the extruded sheet. The processing ductility of the polyamide composite was evaluated by the maximum traction speed at which continuous extrusion was possible and the surface of the extruded sheet was intact. The higher the maximum traction speed, the better the processing ductility of the polyamide composite during extrusion.

[0049] 2) Uniformity: The polyamide composite materials in each example and comparative example were dried at 100-120℃ for 4-6 hours and then extruded into sheets in a single-screw extruder. The sheet samples with a length of 60mm × width of 60mm × thickness of 0.15mm were divided into 9 regions at uniform intervals, and the light transmittance of each region was tested (test standard is GB / T2410-2008). The difference between the maximum and minimum light transmittance values ​​in the 9 regions was used as the index for evaluating the uniformity of the extruded sample. The smaller the value of this index, the better the uniformity of the sample.

[0050] Table 3. Performance of polyamide composites in each example and comparative example.

[0051]

[0052] According to the data in Table 3, the processing flexibility of the polyamide composites in Examples 1-13 reached 4.5 m / min or higher and the uniformity was ≤2.5%, indicating that the polyamide composites of the present invention have good processing flexibility and can significantly improve the uniformity of the obtained products. Specifically, as shown in Examples 1 and Comparative Examples 1-3, using ethylene-maleic anhydride copolymer instead of methyl vinyl ether-maleic anhydride copolymer combined with polytetrafluoroethylene as a tackifier, or using methyl vinyl ether-maleic anhydride copolymer or polytetrafluoroethylene alone as a tackifier, is difficult to effectively improve the processing flexibility of the polyamide composites and the uniformity of the obtained products. This indicates that methyl vinyl ether-maleic anhydride copolymer and polytetrafluoroethylene have a synergistic effect; only the combination of the two can endow the polyamide composites with good processing flexibility and the obtained products with excellent uniformity.

[0053] 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 polyamide composite material, characterized in that, By weight, it includes the following components: Polyamide 94~99.7 parts, tackifier 0.2~4 parts, processing aid 0.1~2 parts; The tackifier comprises methyl vinyl ether-maleic anhydride copolymer and polytetrafluoroethylene; the mass ratio of the methyl vinyl ether-maleic anhydride copolymer to polytetrafluoroethylene is (0.1~1):(0.1~3).

2. The polyamide composite material as described in claim 1, characterized in that, The polyamide composite material comprises the following components in parts by weight: 96-98 parts polyamide, 1.3-3.3 parts tackifier, and 0.5-1 part processing aid.

3. The polyamide composite material as described in claim 1, characterized in that, The mass ratio of the methyl vinyl ether-maleic anhydride copolymer to polytetrafluoroethylene is (0.1~0.9):(1.4~2.2).

4. The polyamide composite material as described in claim 1, characterized in that, The number average molecular weight of the methyl vinyl ether-maleic anhydride copolymer is 70,000 to 320,000 g / mol; And / or, the number average molecular weight of the polytetrafluoroethylene is 10,000 to 50,000 g / mol.

5. The polyamide composite material as described in claim 1, characterized in that, The viscosity of the polyamide is 100~300mL / g.

6. The polyamide composite material according to claim 1, characterized in that, The polyamide includes at least one of PA6, PA11, PA12, PA46, PA56, PA66, PA610, PA612, PA6T, PA9T, PA10T, PA1010, and PA1012.

7. The method for preparing the polyamide composite material according to any one of claims 1 to 6, characterized in that, The process includes the following steps: after mixing the components evenly, the mixture is melt-extruded to obtain a polyamide composite material.

8. The use of the polyamide composite material according to any one of claims 1 to 6 in the preparation of nylon filaments, nylon films, nylon tubes or sheets.

9. A nylon tube or sheet, characterized in that, The polyamide composite material according to any one of claims 1 to 6.

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