Nylon grass filaments, method of manufacture and use

Abstract

This invention belongs to the field of artificial turf technology, and discloses a nylon grass fiber, its preparation method, and its application. The nylon grass fiber, by weight, comprises 100 parts nylon, 5-20 parts LLDPE, 3-10 parts maleic anhydride-grafted PE, 3-6 parts modified nano-silica, 1-3 parts silicone masterbatch, 0.3-0.6 parts antioxidant, and 8 parts color masterbatch. This invention solves the problems of high energy consumption, low yield, and insufficient abrasion resistance in the production of existing nylon artificial turf fibers.

Description

Technical Field

[0001] This invention belongs to the field of artificial turf technology, specifically relating to a nylon grass fiber, its preparation method, and its application. Background Technology

[0002] Currently, nylon-based simulated grass fibers have become a core material in sports fields, landscaping, and pet supplies due to their advantages such as wear resistance, aging resistance, and low maintenance costs. Existing nylon grass fibers are mostly produced using PA6 and PA66 as raw materials through a traditional spinning-stretching-setting-cutting process. However, this process has several drawbacks: In terms of performance, nylon grass fibers are prone to fading and becoming brittle after prolonged exposure to sunlight, and are also prone to breakage in low-temperature environments. They also exhibit poor resilience after repeated rolling. In terms of manufacturing processes, the drawing temperature reaches over 260℃, resulting in energy costs accounting for over 30% of production costs. Furthermore, issues such as fiber breakage and uneven thickness during the stretching process maintain a defect rate of 8-12%, and it is difficult to customize grass fibers with different properties. In terms of cost, high-end raw materials rely on imports, and their prices fluctuate greatly, further compressing profit margins. Although the industry has attempted to improve the process by adding UV-resistant additives, using low-temperature spinning, and developing hollow grass fibers, limitations remain, including easy leaching of additives, decreased grass fiber strength, and complex processes that hinder large-scale production. Therefore, developing a high-performance, low-energy-consumption, and environmentally friendly nylon grass fiber has become an urgent need for the industry to break through development bottlenecks. Summary of the Invention

[0003] To address the aforementioned technical problems, the present invention aims to provide a nylon artificial grass fiber, its preparation method, and its application, thereby solving the problems of high energy consumption, low yield, and insufficient wear resistance in the production of existing nylon artificial grass fibers.

[0004] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a nylon grass filament, which, by weight, comprises 100 parts nylon, 5-20 parts LLDPE, 3-10 parts maleic anhydride-grafted PE, 3-6 parts modified nano-silica, 1-3 parts silicone masterbatch, 0.3-0.6 parts antioxidant and 8 parts color masterbatch, wherein the relative viscosity of the nylon is 2.4-2.8.

[0005] Preferably, the modified nano-silica has a mesh size of 30,000 to 40,000 mesh.

[0006] More preferably, modified nano-silica refers to nano-silica modified by silane coupling agent KH550.

[0007] More preferably, the modification method of modified nano-silica is as follows: the nano-silica is stirred at high speed and preheated at 80~100℃ for 10~15 min, then a silane coupling agent is added, the amount of silane coupling agent added is 2~5% of the mass of nano-silica, and the mixture is stirred at high speed for 15~20 min and then cooled to room temperature to obtain modified nano-silica.

[0008] Preferably, LLDPE is an octane polyolefin elastomer.

[0009] More preferably, the melt index of LLDPE is 2 kg / 10min. In a second aspect, the present invention provides a method for preparing nylon grass fibers, comprising the following steps: S1. Raw material pretreatment: Nylon, LLDPE and maleic anhydride-grafted PE are vacuum dried at 80~90℃ for 3~6 h to obtain pretreated mixture; S2. Mixed drawing: The pretreated mixture, modified nano-silica, silicone masterbatch, antioxidant, and color masterbatch are added to a single screw drawing machine and melt-extruded at a temperature of 230~260℃. After extrusion through a spinneret, the material is cooled, stretched, and shaped to obtain nylon grass fibers. The production line speed is 90~95 m / min.

[0010] Preferably, in step S2, the temperature of melt extrusion is 235~245℃.

[0011] Preferably, in step S2, the screw speed of the melt extrusion is 200~300 r / min, and the pressure before the pump is 6~8 MPa.

[0012] Preferably, in step S2, the stretching ratio is 2 to 5 times, and the setting temperature is 120 to 140°C.

[0013] In a third aspect, the present invention proposes an application of nylon grass fibers, which are used to prepare artificial turf, outdoor carpets or sports field paving materials.

[0014] Beneficial effects: The present invention produces nylon grass fibers that achieve the following goals: UV resistance level of grass fibers is improved to level 8 or above, low temperature breaking strength is increased by 20%, production energy consumption is reduced by 15%, and the yield rate is increased to over 95%, effectively solving the problem of insufficient performance of existing nylon artificial grass fibers. Detailed Implementation

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, specific implementation methods of the present invention will be described below with reference to the embodiments. Obviously, the following description is only some embodiments of the present invention. For those skilled in the art, other implementation methods can be obtained based on these embodiments without creative effort.

[0016] This invention proposes a nylon grass filament, which, by weight, comprises 100 parts nylon, 5-20 parts LLDPE, 3-10 parts maleic anhydride-grafted PE, 3-6 parts modified nano-silica, 1-3 parts silicone masterbatch, 0.3-0.6 parts antioxidant, and 8 parts color masterbatch. The nylon is of medium to low viscosity, for example, the relative viscosity of the nylon is 2.4-2.8.

[0017] This invention uses medium-to-low viscosity nylon, which has low flow resistance. Furthermore, the shorter molecular chains of low-viscosity nylon result in stronger fluidity in the molten state, allowing it to pass more smoothly through the narrow channels of the drawing die, reducing pressure loss during extrusion and lowering equipment load. Maleic anhydride-grafted PE increases the compatibility between nylon and LLDPE, improving mechanical and processing properties. Based on the formulation of this invention, the grass fiber forming stability is high, and the uniform viscosity of the material results in better consistency in the thickness of individual fibers during drawing, reducing the likelihood of localized areas of excessively thin or thick fibers, and ensuring stable production of standard-compliant grass fiber.

[0018] Preferably, the nylon is nylon 6, i.e., PA6.

[0019] In this invention, the entire formulation system has the following advantages compared to traditional high-viscosity nylon processing: Based on the grass fiber formulation of this invention, the processing temperature can be reduced. Compared to high-viscosity nylon, low-viscosity nylon materials do not require excessively high melting temperatures to achieve the fluidity required for fiber drawing, thus saving energy. It can also reduce the damage of high temperatures to the molecular structure of the material, preserving the toughness and strength of nylon. In addition, this invention is conducive to improving production efficiency. The faster flow rate allows for higher fiber drawing speeds, and more filaments can be produced in the same amount of time, which is especially suitable for large-scale continuous fiber drawing production.

[0020] In this invention, the modified nano-silica has a mesh size of 30,000 to 40,000 mesh. Modified nano-silica can reduce the coefficient of friction of the material and improve the surface hardness of the grass fibers. More preferably, the modified nano-silica refers to nano-silica modified with the silane coupling agent KH550. The specific modification method is as follows: Nano-silica is placed in a high-speed mixer and preheated at 80-100°C for 10-15 minutes. Then, the silane coupling agent KH550 is added, with the amount of silane coupling agent added being 2-5% of the mass of the nano-silica. The mixture is then mixed at high speed (e.g., 800-1000 r / min) for 15-20 minutes and cooled to room temperature to obtain the modified nano-silica.

[0021] Preferably, the LLDPE is an octane PE, i.e., an octane polyolefin elastomer (POE), and more preferably, the melt index of the LLDPE is 2 kg / 10 min.

[0022] Based on the above-mentioned nylon grass fibers, the present invention also proposes a method for preparing nylon grass fibers, comprising the following steps: S1. Raw material pretreatment: Nylon, LLDPE, and maleic anhydride-grafted PE are dried in a vacuum drying oven at 80~90℃ for 3~6 h to obtain a pretreated mixture; S2. Mixed drawing: The pretreated mixture, modified nano-silica, silicone masterbatch, antioxidant, and color masterbatch are added to a single screw drawing machine and melt-extruded at a temperature of 230~260℃. After extrusion through a spinneret, the material is cooled, stretched, and shaped to obtain nylon grass fibers. The production line speed is 90~95 m / min.

[0023] Preferably, in step S2, the melt extrusion temperature is 235~245℃, the screw speed is 200~300 r / min, and the pump pressure is 6~8 MPa.

[0024] Preferably, in step S2, the draft ratio is 2 to 5 times, and the setting temperature is 120 to 140°C. The draft ratio affects the quality and strength of the straw fibers. Generally, the higher the draft ratio, the greater the strength of the straw fibers, but the more prone they are to breakage during production, affecting production efficiency. Conversely, a lower draft ratio makes the straw fibers prone to poor drafting, resulting in knotted yarns. In addition, the lower strength of the straw fibers also affects their performance. This invention selects a specific draft ratio based on the formula, which is beneficial for producing straw fibers that meet performance standards.

[0025] In this invention, based on specific formulation components, the processing temperature can be reduced and production efficiency improved. In existing technologies, the processing temperature (i.e., melt extrusion temperature) is generally above 265°C, such as 265~280°C. This invention can reduce the processing temperature to below 260°C, even reaching 235~245°C. Furthermore, the production efficiency of this invention is increased from the conventional 60~70 m / min to 90~95 m / min. Therefore, this invention achieves the goal of reducing energy consumption in nylon filament production.

[0026] The technical solution of the present invention will be described in detail below with specific embodiments.

[0027] Example 1 In this embodiment, the grass fiber raw material comprises 100 parts nylon 6, 5 parts LLDPE, 5 parts maleic anhydride-grafted PE, 4 parts modified nano silica, 2 parts silicone masterbatch, 0.6 parts antioxidant and 8 parts color masterbatch, calculated by mass.

[0028] Preparation method S1. Raw material pretreatment: Nylon, LLDPE, and maleic anhydride-grafted PE are dried in a vacuum drying oven at 80°C to obtain a pretreated mixture. S2. Mixed drawing: The pretreated mixture, modified nano-silica, silicone masterbatch, antioxidant, and color masterbatch are added to a single-screw drawing machine and melt-extruded at a temperature of 240℃. After extrusion through a spinneret, the material is cooled, drawn, and shaped. The drawing ratio is 3.5 times, the shaping temperature is 135℃, and the production speed is 90 m / min to obtain nylon grass fibers.

[0029] Comparative Example 1 In this comparative example, 100% LLDPE was used.

[0030] The preparation method is as follows: by mass, the grass fiber raw material includes 100 parts LLDPE, 2 parts silicone masterbatch, and 8 parts color masterbatch.

[0031] Preparation method S1. Raw material pretreatment: Weigh LLDPE, silicone masterbatch and color masterbatch according to the proportion and mix them evenly to obtain pretreated mixture. S2. Mixed drawing: The pretreated mixture is added to a single screw drawing machine, melted and extruded at a temperature of 230°C. After being extruded through a spinneret, it is cooled, drawn, and shaped. The drawing ratio is 5 times and the shaping temperature is 130°C to obtain the grass fiber of Comparative Example 1.

[0032] Comparative Example 2 In this comparative example, 100% nylon was used. By weight, the grass fiber raw material consisted of 100 parts nylon 6, 2 parts silicone masterbatch, 0.6 parts antioxidant, and 8 parts color masterbatch.

[0033] The preparation method is as follows: S1. Raw material pretreatment: Nylon is dried in a vacuum drying oven at 80°C to obtain a pretreated mixture; S2. Mixed drawing: The pretreated mixture, silicone masterbatch, antioxidant, and color masterbatch are added to a single-screw drawing machine and melt-extruded at a temperature of 270℃. After extrusion through a spinneret, the mixture is cooled, drawn, and shaped. The drawing ratio is 3.5 times, the sizing temperature is 135℃, and the production speed is 65 m / min, to obtain nylon grass fibers of Comparative Example 2.

[0034] Comparing Example 1 with Comparative Example 2, it can be seen that the present invention can effectively reduce production temperature and increase production speed, which is beneficial to reducing production energy consumption.

[0035] The grass fibers obtained in Example 1 and Comparative Examples 1-2 were subjected to performance tests, and the results are shown in Table 1.

[0036] Table 1. Grass fiber properties of Example 1 and Comparative Examples 1-2.

[0037] .

[0038] The embodiments provided by the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention, and the descriptions of the embodiments above are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A type of nylon grass fiber, characterized in that, By weight, the raw materials include 100 parts nylon, 5-20 parts LLDPE, 3-10 parts maleic anhydride-grafted PE, 3-6 parts modified nano silica, 1-3 parts silicone masterbatch, 0.3-0.6 parts antioxidant and 8 parts color masterbatch, wherein the relative viscosity of nylon is 2.4-2.

8.

2. The nylon grass fibers according to claim 1, characterized in that, The modified nano-silica has a mesh size of 30,000 to 40,000 mesh.

3. The nylon grass fibers according to claim 2, characterized in that, Modified nano silica refers to nano silica modified by the silane coupling agent KH550.

4. The nylon grass fibers according to claim 3, characterized in that, The modification method of modified nano silica is as follows: stir nano silica at high speed and preheat it at 80~100℃ for 10~15 min, then add silane coupling agent, the amount of silane coupling agent added is 2~5% of the mass of nano silica, mix at high speed for 15~20 min and then cool to room temperature to obtain modified nano silica.

5. The nylon grass fibers according to claim 1, characterized in that, The melt index of LLDPE is 2 kg / 10min.

6. A method for preparing nylon grass fibers, characterized in that, The preparation of nylon grass fibers as described in any one of claims 1-5 comprises the following steps: S1. Raw material pretreatment: Nylon, LLDPE and maleic anhydride-grafted PE are vacuum dried at 80~90℃ for 3~6 h to obtain pretreated mixture; S2. Mixed drawing: The pretreated mixture, modified nano-silica, silicone masterbatch, antioxidant, and color masterbatch are added to a single screw drawing machine and melt-extruded at a temperature of 230~260℃. After extrusion through a spinneret, the material is cooled, stretched, and shaped to obtain nylon grass fibers. The production line speed is 90~95 m / min.

7. The preparation method according to claim 6, characterized in that, In step S2, the temperature of melt extrusion is 235~245℃.

8. The preparation method according to claim 6, characterized in that, In step S2, the screw speed of the melt extrusion is 200~300 r / min, and the pressure before the pump is 6~8 MPa.

9. The preparation method according to claim 6, characterized in that, In step S2, the stretching ratio is 2 to 5 times, and the setting temperature is 120 to 140°C.

10. An application of nylon grass fibers, characterized in that, The nylon grass fibers as described in any one of claims 1-5 are used to prepare artificial turf, outdoor carpets, or sports field paving materials.