A nylon composition, its preparation and use

Abstract

The application discloses a nylon composition and a preparation method and application thereof, and belongs to the technical field of polymer engineering plastics; the nylon composition provided by the application comprises the following components in parts by mass: 73-92 parts of PA12 resin, 3-22 parts of a toughening agent, 0.3-1.8 parts of lignosulfonate, and 0.1-1.2 parts of polyvinylpyrrolidone; the toughening agent comprises maleic anhydride grafted SEBS. The product prepared by the application has high light transmittance and excellent bending modulus and impact strength; meanwhile, the preparation method of the nylon composition is simple in operation and is beneficial to actual production.

Description

Technical Field

[0001] This invention belongs to the field of polymer engineering plastics technology, and particularly relates to a nylon composition, its preparation method and application. Background Technology

[0002] Transparent nylon PA12 is a special type of nylon that is almost non-crystalline or crystallizes very slowly. It boasts advantages such as high light transmittance (above 90%), good thermal stability, resistance to chemical corrosion, and low water absorption. PA12 often uses POE-g-MAH (ethylene-octene copolymer grafted maleic anhydride) as a toughening agent, which can significantly improve the material's deflection and flexural modulus. However, this toughening agent has poor light transmittance and a significant decrease in impact strength. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a nylon composition with good light transmittance, flexural modulus and impact strength, as well as its preparation method and application.

[0004] To achieve the above objectives, in a first aspect of the present invention, the present invention provides a nylon composition comprising the following components in parts by weight: 73-92 parts PA12 resin, 3-22 parts toughening agent, 0.3-1.8 parts lignite, and 0.1-1.2 parts polyvinylpyrrolidone; The toughening agent comprises maleic anhydride-grafted SEBS.

[0005] The present invention provides a nylon composition that, by selecting appropriate types of components for compounding, can effectively achieve high light transmittance, as well as excellent flexural modulus and impact strength.

[0006] Specifically, in the first aspect, the present invention selects maleic anhydride-grafted SEBS as a toughening agent, which can effectively improve the compatibility between components and improve the flexural modulus and impact strength of the composition while maintaining good light transmittance. In the second aspect, the present invention selects lignite as a nucleating agent, which can effectively increase nucleation sites, increase the nucleation rate of smaller crystals in the composition, and avoid the formation of larger crystals; simultaneously, it combines polyvinylpyrrolidone as a crystallization inhibitor, which can more effectively reduce the formation of larger crystals, thereby effectively improving the light transmittance of the composition.

[0007] For example, the mass fraction of the PA12 resin can be any point value or any two points within a range of 73-92 parts, such as 75-90 parts, or 73, 75, 78, 80, 82, 84, 86, 88, 90, 92, etc.; the toughening agent can be any point value or any two points within a range of 3-22 parts, such as 5-20 parts, or 3, 5, 8, 10, 12, 14, 16, 18, 20, 22, etc. The lignite can be any point value or any two-point range between 0.3 and 1.8 parts, for example, it can be 0.5-1.5 parts, or 0.3 parts, 0.5 parts, 0.8 parts, 1 part, 1.2 parts, etc.; the polyvinylpyrrolidone can be any point value or any two-point range between 0.1 and 1.2 parts, for example, it can be 0.2-1 part, or 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.2 parts, etc.

[0008] Preferably, the nylon composition contains PA12 resin at a mass percentage of ≥70%.

[0009] More preferably, the mass percentage of PA12 resin in the nylon composition is 75-96%.

[0010] As a preferred embodiment of the nylon composition of the present invention, the nylon composition comprises the following components in parts by weight: 80-85 parts PA12 resin, 14-18 parts toughening agent, 0.8-1.2 parts lignite, and 0.4-0.6 parts polyvinylpyrrolidone.

[0011] The present invention has found that the mass fraction of the components in the nylon composition affects the overall performance of the composite material. When the mass fraction of the components in the composite material is further selected within the above-mentioned range, the overall performance of the obtained composite material is even better.

[0012] In a preferred embodiment of the nylon composition of the present invention, the viscosity K value of the polyvinylpyrrolidone is ≥25.

[0013] It should be noted that the test method for the viscosity K value of polyvinylpyrrolidone (PVP) is as follows: the Ubbelohde viscosity test method is used, the test standard is DIN 53000-1:2023, the test temperature is 25℃, and a PVP solution with a concentration of 10g / L is prepared using deionized water as a solvent for testing.

[0014] Preferably, the viscosity number K of the polyvinylpyrrolidone is 25-95.

[0015] For example, the viscosity K value of the polyvinylpyrrolidone can be any point value or any two-point range value between 25 and 95, such as 30-90, 30-60, 60-90, etc., or 25, 30, 35, 40, 45, 50, 55, 60, 65, 75, 80, 85, 90, 95, etc.

[0016] Preferably, the viscosity K value of the polyvinylpyrrolidone is 55-95. For example, it can be 55, 60, 65, 70, 75, 80, 85, 90, 95, etc.

[0017] This invention has discovered that the carbonyl group in polyvinylpyrrolidone (PVP) is a strongly polar group and a hydrogen bond acceptor. It can adsorb or entangle on the PA12 molecular chain or at the interface between the amorphous and crystalline regions through hydrogen bonding. This can hinder the regular arrangement and movement of PA12 molecular chain segments, increase the difficulty of its diffusion into the crystal lattice, thereby slowing down the crystallization rate, reducing crystallinity, and refining the size of the crystal spheres. Furthermore, when the viscosity number K of polyethylene is selected within the above-mentioned range, especially within a more preferred range, it can better interact with lignite and also better distribute at the interface between the amorphous and crystalline regions, thus improving the overall performance of the composition.

[0018] In a preferred embodiment of the nylon composition of the present invention, the total mass content of metal ions in the lignite is 0.5-10%.

[0019] It should be noted that the test method for the total mass content of metal ions in the lignite salt is XRF fluorescence elemental analysis, and the test standard is ISO 12677:2011.

[0020] For example, the total mass content of metal ions in the lignite can be any point value or any two points between 0.5% and 10%, such as 1-9%, 1-5%, 5-9%, or 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0021] Preferably, the total mass content of metal ions in the lignite is 4-6%.

[0022] The present invention has found that when the total mass content of metal ions in lignite is further selected to be within the above-mentioned range, the overall effect of the resulting composition is even better.

[0023] It should be noted that the present invention does not particularly limit the type of metal ions in lignite. Exemplarily, the metal ions may be calcium ions, sodium ions, zinc ions, etc.

[0024] As a preferred embodiment of the nylon composition of the present invention, the PA12 resin has a melt index of 20-40 g / 10 min at 260°C / 5 kg.

[0025] It should be noted that the test method for the melt index of the PA12 resin at 260℃ / 5kg is based on ISO1133-1:2011.

[0026] For example, the melt flow index of the PA12 resin at 260℃ / 5kg can be any point value or any two-point range between 20-40g / 10min, such as 22-37g / 10min, or 20g / 10min, 22g / 10min, 25g / 10min, 28g / 10min, 30g / 10min, 32g / 10min, 35g / 10min, 38g / 10min, 40g / 10min, etc.

[0027] As a preferred embodiment of the nylon composition of the present invention, the toughening agent further includes at least one of ethylene-acrylate ionic copolymer and ethylene-methacrylate-acrylate copolymer.

[0028] The present invention has found that when at least one of ethylene-acrylic acid ion copolymer and ethylene-methacrylic acid-acrylate copolymer (EMAA) is selected as a toughening agent, it can better interact with maleic anhydride-grafted SEBS, thereby achieving high flexural modulus and cantilever beam notched impact strength of the composition while ensuring excellent light transmittance.

[0029] It should be noted that the ions in the ethylene-acrylic acid ionic copolymer include sodium ions, zinc ions, etc. This application does not specifically limit the ion mass content in the ethylene-acrylic acid ionic copolymer; exemplarily, the ion mass content in the ethylene-acrylic acid ionic copolymer can be 0.5-3%.

[0030] In a preferred embodiment of the nylon composition of the present invention, the toughening agent contains 45-90% by mass of maleic anhydride-grafted SEBS.

[0031] For example, the mass percentage of maleic anhydride-grafted SEBS in the toughening agent can be any point value or any two points between 45% and 90%, such as 50-87.5%, 50-75%, 75-87.5%, or 45%, 48%, 50%, 52%, 55%, 58%, 60%, 62%, 65%, 68%, 70%, 72%, 75%, 78%, 80%, 82%, 85%, 88%, 90%, etc.

[0032] Preferably, the toughening agent contains 70-80% by mass of maleic anhydride-grafted SEBS.

[0033] The present invention has found that by further selecting the toughening agent in which the mass percentage of maleic anhydride-grafted SEBS is within the above-mentioned range, the excellent overall performance of the composition can be better achieved.

[0034] As a preferred embodiment of the nylon composition of the present invention, the maleic anhydride-grafted SEBS has a melt index of 1-10 g / 10 min at 190°C / 5 kg.

[0035] It should be noted that the test method for the melt index of the maleic anhydride-grafted SEBS at 190℃ / 5kg is in accordance with ISO 1133-1:2011.

[0036] For example, the melt index of the maleic anhydride-grafted SEBS at 190℃ / 5kg can be any point value between 1 and 10 g / 10min or a range between any two points, such as 2-8 g / 10min, 2-5 g / 10min, 5-8 g / 10min, etc., or 1 g / 10min, 2 g / 10min, 3 g / 10min, 4 g / 10min, 5 g / 10min, 6 g / 10min, 7 g / 10min, 8 g / 10min, 9 g / 10min, 10 g / 10min, etc.

[0037] As a preferred embodiment of the nylon composition of the present invention, the ethylene-acrylic acid ion copolymer has a melt index of 0.5-5.5 g / 10 min at 190°C / 2.16 kg.

[0038] It should be noted that the melt index of the ethylene-acrylic acid ionomer at 190℃ / 2.16kg is tested according to ISO 1133-1:2011.

[0039] For example, the melt index of the ethylene-acrylic acid ionic copolymer at 190°C / 2.16 kg can be any point value or any range between two points between 0.5 and 5.5 g / 10 min, such as 1-5 g / 10 min, or 0.5 g / 10 min, 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, 5 g / 10 min, 5.5 g / 10 min, etc.

[0040] As a preferred embodiment of the nylon composition of the present invention, the ethylene-methacrylate-acrylate copolymer has a melt index of 7-14 g / 10 min at 190°C / 2.16 kg.

[0041] It should be noted that the test method for the melt index of the ethylene-methacrylic acid-acrylate copolymer at 190℃ / 2.16kg is in accordance with ISO 1133-1:2011.

[0042] For example, the melt index of the ethylene-methacrylic acid-acrylate copolymer at 190°C / 2.16 kg can be any point value or any range between two points between 7 and 14 g / 10 min, such as 8-13 g / 10 min, or 7 g / 10 min, 8 g / 10 min, 9 g / 10 min, 10 g / 10 min, 11 g / 10 min, 12 g / 10 min, 13 g / 10 min, 14 g / 10 min, etc.

[0043] It should be noted that the present invention does not have any special requirements for the grafting rate of maleic anhydride to SEBS, for example, it can be 0.5-1.5%.

[0044] It should be noted that the present invention does not have any special requirements on the percentage of the mass content of monomers in the ethylene-acrylic acid ion copolymer. For example, the percentage of the mass content of ethylene monomers in the ethylene-acrylic acid ion copolymer can be 40-90%.

[0045] It should be noted that the present invention does not have any special requirements on the percentage of the mass content of monomers in the ethylene-methacrylic acid-acrylate copolymer. For example, the percentage of the mass content of ethylene monomers in the ethylene-methacrylic acid-acrylate copolymer can be 30-90%.

[0046] In a preferred embodiment of the nylon composition of the present invention, the nylon composition further includes 0.1-1.2 parts of lubricant.

[0047] For example, the lubricant includes at least one of magnesium stearate, pentaerythritol stearate, ethylene bis-stearamide, and polyethylene wax.

[0048] In a second aspect, the present invention provides a method for preparing the nylon composition, the method comprising the following steps: The dried raw materials are mixed in proportion and fed into an extruder. After melt extrusion, stretching, cooling, pelletizing and drying, a nylon composition is obtained.

[0049] In a preferred embodiment of the preparation method of the present invention, the extruder is a co-rotating twin-screw extruder with a screw length-to-diameter ratio of (36-48):1, an extrusion temperature of 80-280℃, and a screw speed of 300-400 rpm.

[0050] In a third aspect, the present invention provides a component prepared using the nylon composition described herein.

[0051] For example, the components include industrial transparent tubes, decorative transparent tubes, etc.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows: The nylon composition provided by this invention, through the selection of appropriate mass proportions of components, exhibits excellent interactions between the components, resulting in a product with superior light transmittance, flexural modulus, and cantilever beam notched impact strength. Furthermore, the preparation method of the nylon composition provided by this invention is simple to operate and beneficial for practical production. Detailed Implementation

[0053] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0054] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in the field.

[0055] PA12-1: The measured melt index at 260℃ / 5kg is 37g / 10min, T15, Pingdingshan Beiande; PA12-2: The measured melt flow index at 260℃ / 5kg is 22g / 10min. PA1239, Guangzhou Guosu New Materials. SEBS-g-MAH-1: The measured melt flow index at 190℃ / 5kg is 5g / 10min, KT-2511, Shenyang Ketong; SEBS-g-MAH-2: The measured melt flow index at 190℃ / 5kg is 2g / 10min, FG1901GT, Kraton, USA; SEBS-g-MAH-3: The measured melt flow index at 190℃ / 5kg is 8g / 10min, GPM5618, Ningbo Nengzhiguang; Ethylene-acrylic acid ionomer-1: The measured melt index at 190℃ / 2.16kg was 5g / 10min, IONIA 2610, SK Group; Ethylene-acrylic acid ionomer-2: The measured melt index at 190℃ / 2.16kg was 1g / 10min, IONIA 2151, SK Group; EMAA-1: Melt index measured at 190℃ / 2.16kg was 13g / 10min, AN4228C, Dow Chemical; EMAA-2: Melt index measured at 190℃ / 2.16kg was 8g / 10min, ELVALOY 4170, Dow Chemical; POE-g-MAH: The measured melt index at 190℃ / 5kg is 2g / 10min, FUSABOND N493, Dow Chemical. Lignite 1: Total mass content of metal ions was measured to be 5%, Licocare® RBW 360 powder Vita, Clariant; Lignite 2: The measured total mass content of metal ions was 9%, CEVO @ 2443, Walker Chemicals, Germany; Lignite 3: Total metal ion content measured to be 1%, ADDIMER® 126, KG Company; Talc powder: HTPULTRA5, Liaoning Aihaiyimi Mining Co., Ltd.; PVP-1: The measured viscosity K is 90, PVP-K90, Shanghai Comau New Materials; PVP-2: The measured viscosity K is 60, PVP-K60, Shanghai Comau New Materials; PVP-3: The measured viscosity K is 30, PVP-K30, Shanghai Comau New Materials; Lubricant: Pentaerythritol stearate, commercially available.

[0056] Examples 1-16 and Comparative Examples 1-5 The present invention provides a nylon composition in the embodiments and comparative examples, wherein the component content (parts by weight) of the nylon composition is shown in Tables 1-3; Table 1 Table 2 Table 3 The preparation methods for the examples and comparative examples are as follows: The dried raw materials are mixed in proportion and then added to a mixer for uniform mixing. The mixture is then fed into a twin-screw extruder, and the feed rate of the twin-screw extruder is adjusted to 80 kg / h. After extrusion, stranding, cooling, pelletizing, and drying, a nylon composition is obtained. The parameters of the twin-screw extruder are as follows: the temperature of each screw section from the feed port to the die head is 80℃, 260℃, 250℃, 240℃, 240℃, 180℃, 180℃, 180℃, 200℃, and 230℃, respectively; the twin-screw speed is 300 rpm; and the length-to-diameter ratio is 40:1.

[0057] Example of effect The nylon compositions prepared in the examples and comparative examples were tested, including the following aspects: 1. Transmittance: The average transmittance in the visible light range (380-760nm) is tested. Specifically, the test is performed once every 1 minute for a total of 3 times. The average value is taken after the test. The test is conducted in accordance with GB / T 2410:2008. 2. Flexural modulus: Tested according to ISO 178:2019; 3. Cantilever beam notched impact strength: Tested according to ISO 180-2000, notch type A; The results are shown in Table 4. Table 4 As can be seen from Table 4, when the technical solution provided by this invention is adopted, the obtained product has excellent light transmittance, high flexural modulus, and cantilever beam notched impact strength; specifically, the light transmittance of the obtained product is above 85.6%, the flexural modulus is above 1020 MPa, and the cantilever beam notched impact strength is above 49 kJ / m. 2 above; As can be seen from the embodiments and Comparative Example 1, the technical solution of the present invention can significantly improve the notched impact strength and light transmittance of the product cantilever beam, while also ensuring good flexural modulus. As can be seen from Example 1 and Comparative Example 2, when PVP is not added in Comparative Example 2, the light transmittance of the obtained product shows a decreasing trend, and the flexural modulus also decreases significantly. As can be seen from Example 1 and Comparative Example 3, when talc powder is used to replace lignite, the cantilever beam notched impact strength of the obtained product is significantly reduced. As can be seen from Example 1 and Comparative Example 4, when maleic anhydride is used to graft SEBS with other substances, the light transmittance of the obtained product decreases significantly, and the flexural modulus also shows a decreasing trend. As can be seen from Example 1 and Comparative Example 5, when maleic anhydride is not added to graft SEBS, the cantilever beam notched impact strength of the obtained product decreases significantly, and the flexural modulus also shows a decreasing trend.

[0058] Finally, it should be noted that the above embodiments are used to illustrate the technical solutions of the present invention and not 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 nylon composition, characterized in that, The nylon composition comprises the following components in parts by weight: 73-92 parts PA12 resin, 3-22 parts toughening agent, 0.3-1.8 parts lignite, 0.1-1.2 parts polyvinylpyrrolidone; The toughening agent comprises maleic anhydride-grafted SEBS.

2. The nylon composition according to claim 1, characterized in that, The nylon composition comprises the following components in parts by weight: 80-85 parts PA12 resin, 14-18 parts toughening agent, 0.8-1.2 parts lignite, 0.4-0.6 parts polyvinylpyrrolidone.

3. The nylon composition according to claim 1, characterized in that, The viscosity K value of the polyvinylpyrrolidone is ≥25.

4. The nylon composition according to claim 1, characterized in that, The total mass content of metal ions in the lignite is 0.5-10%.

5. The nylon composition according to claim 1, characterized in that, The melt flow index of the PA12 resin at 260℃ / 5kg is 20-40g / 10min.

6. The nylon composition according to claim 1, characterized in that, The toughening agent further includes at least one of ethylene-acrylic acid ion copolymer and ethylene-methacrylic acid-acrylate copolymer; preferably, the mass percentage of maleic anhydride-grafted SEBS in the toughening agent is 45-90%.

7. The nylon composition according to claim 6, characterized in that, The melt index of the maleic anhydride-grafted SEBS at 190℃ / 5kg is 1-10g / 10min; And / or, the melt index of the ethylene-acrylic acid ionic copolymer at 190°C / 2.16 kg is 0.5-5.5 g / 10 min; And / or, the ethylene-methacrylic acid-acrylate copolymer has a melt index of 7-14 g / 10 min at 190 °C / 2.16 kg.

8. The nylon composition according to claim 1, characterized in that, The nylon composition also includes 0.1-1.2 parts of lubricant.

9. The method for preparing the nylon composition according to any one of claims 1-7, characterized in that, The preparation method includes the following steps: the dried raw materials are mixed in proportion and fed into an extruder, and then melt-extruded, stretched, cooled, pelletized and dried to obtain a nylon composition.

10. A component, characterized in that, The component is prepared using the nylon composition as described in any one of claims 1-8.

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