Weather-resistant soft PA6 artificial turf thread material and preparation method thereof

Abstract

The invention relates to the technical field of high polymer material modification, in particular to a weather-resistant soft PA6 artificial turf filament material and a preparation method thereof.The weather-resistant soft PA6 artificial turf filament material is prepared from, by weight, 50-80 parts of PA6, 2-5 parts of a lubricating dispersant, 10-25 parts of a toughening compatilizer and 1-3 parts of a stabilizer through melt blending extrusion, granulation and extrusion wire drawing; wherein the stabilizer comprises an antioxidant and a light stabilizer; the antioxidant is composed of at least two of an antioxidant 1790, an antioxidant 330 and an antioxidant 3114; the light stabilizer is composed of at least two of UV928, UV119S and UV660, and the light stabilizer is composed of at least two of UV928, UV119S The PA6 lawn silk is soft in hand feeling, good in sports comfort and safety, stable in quality and good in weather resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer material modification, and particularly relates to a weather-resistant and soft PA6 artificial turf yarn material and a preparation method thereof. Background Art

[0002] PA6 turf is mainly used in formal competition venues, such as football fields, hockey fields, amateur football schools and training venues. Compared with conventional PE and PP turfs, it has good stability, friction with the skin, shock absorption and abrasion resistance. PA6 turf can be used for laying track and field runways, baseball fields, rugby fields, around swimming pools and greening of leisure venues by selecting a variety of additives according to the needs of different sports field functions to form an artificial turf woven from fibers. It is a multi-functional sports field laying material. It has all-weather, weather resistance, recovery, air and water permeability, economy, sound absorption and noise reduction, long green simulation, good sports safety, and excellent physical and chemical properties for multiple uses. Since pure PA6 has high rigidity and poor flexibility, and in addition, PA6 artificial turf is exposed outdoors for a long time and ages due to sunlight and rain, ordinary PA6 is not suitable for the production and application of artificial turf yarn. It is necessary to improve the flexibility and aging resistance of PA6 turf yarn through modification technology. Summary of the Invention

[0003] In order to solve the technical problem that ordinary PA6 in the prior art cannot meet the application requirements of turf yarn, a weather-resistant and soft PA6 artificial turf yarn material and a preparation method thereof are provided. The PA6 turf yarn of the present invention has better flexibility and aging resistance.

[0004] A weather-resistant and soft PA6 artificial turf yarn material is prepared by melt-blending and extruding the following raw materials in parts by weight and pelletizing:

[0005] 50 - 80 parts of PA6, 2 - 5 parts of lubricating and dispersing agent, 10 - 25 parts of toughening compatibilizer, 1 - 3 parts of stabilizer;

[0006] Wherein the stabilizer includes an antioxidant and a light stabilizer;

[0007] The antioxidant is composed of at least two of antioxidant 1790, antioxidant 330, and antioxidant 3114; the light stabilizer is composed of at least two of UV928, UV119S, and UV660.

[0008] Further, the antioxidant is composed of antioxidant 1790 and one of antioxidant 330 and antioxidant 3114 in a mass ratio of 1:2;

[0009] The light stabilizer is composed of any two of UV928, UV119S, and UV660 in an equal mass ratio.

[0010] Antioxidant 1790 is 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, with a relatively large molecular weight, a melting point of about 345°C, low volatility, good migration resistance, and no color staining; Antioxidant 330 belongs to polyhydric hindered phenol antioxidants, with a melting point of 242-246°C, stable processability at high temperatures, good heat resistance, no pollution, no color change, and low toxicity; Antioxidant 3114 is 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanuric acid, belonging to a trifunctional hindered phenol type antioxidant, with low volatility, good migration resistance, improving the heat and light oxidation resistance of materials, having a synergistic effect when used in combination with light stabilizers, and further improving the photo-thermal stability; The CAS No. of UV928 is 73936-91-1, with low volatility, suitable for use in high-temperature environments, reducing volatilization loss, and having excellent performance when compounded with hindered amine light stabilizers; The CAS No. of UV119S is 106990-43-6, belonging to a non-polymeric high-molecular-weight hindered amine light stabilizer, with low volatility, good migration resistance, and improving the thermal aging oxidation resistance of materials; The CAS No. of UV660 is 42774-15-2. Due to having an amide group, it has good compatibility with nylon, provides the melt processing ability of nylon, stabilizes the melt pressure of nylon, makes the processing process smooth, reduces the problem of filament breakage during fiber spinning, and at the same time, as a free radical scavenger itself, it can improve the thermal stability and light stability of PA synchronously.

[0011] Furthermore, the relative viscosity of PA6 is 2.4 - 2.8.

[0012] Furthermore, the lubricating dispersant is selected from at least one of zinc stearate, calcium stearate, ethylene bisstearamide (EBS), and silicone powder.

[0013] Furthermore, the toughening compatibilizer is at least one of maleic anhydride grafted POE (POE-g-MAH) and glycidyl methacrylate grafted LDPE (LDPE-g-GMA).

[0014] A preparation method of a weather-resistant and soft PA6 artificial turf yarn material includes the following steps:

[0015] S1. Mix PA6, a lubricating dispersant, a toughening compatibilizer, and a stabilizer evenly to obtain a mixed material;

[0016] S2. Carry out melt blending extrusion on the mixed material and granulate.

[0017] Furthermore, the mixing temperature of the mixed material is 90 - 110°C, and the mixing time is 8 - 14 min.

[0018] Further, the melt blending and extrusion is carried out by a twin-screw extruder, and the temperatures of each zone are: T 1 = 150 - 160 °C, T 2 = 160 - 180 °C, T 3 = 200 - 230 °C, T 4 = 200 - 230 °C, T 5 = 200 - 230 °C, T 6 = 200 - 230 °C, T 7 = 220 - 240 °C, T 8 = 220 - 240 °C, T 9 = 220 - 240 °C, T 模 = 190 - 200 °C.

[0019] Beneficial technical effects:

[0020] For the weather-resistant and soft PA6 turf yarn material and its preparation method of the present invention, the used stabilizers have good synergistic effects, ensuring good thermal-oxidative aging resistance and high weather resistance during the production process of the PA6 artificial turf yarn material, and greatly improving the service life of the material applied to PA6 turf yarn; when the material of the present invention is applied to artificial turf yarn, under the conditions of UVA-340 light source, lamp irradiance of 1.55 W / m 2 , irradiation time of 8 h, irradiation temperature of 60 °C, spraying time of 15 min, condensation time of 3 hours and 45 minutes, and condensation temperature of 50 °C for cyclic testing, and the testing times are 1800 hours, 2200 hours, and 2500 hours respectively, the retention rates of tensile strength reach 66%, 60.8%, and 56.8% respectively, and the retention rates of elongation at break are 36.5%, 31.4%, and 30.7% respectively; while ordinary nylon turf yarns all break after being tested for 500 hours under the above testing conditions.

[0021] The compatibilizer used in the PA6 turf yarn material of the present invention has good toughening effects, significantly improving the softness of the hand feeling of nylon artificial turf, the sports comfort and safety of artificial turf; and the lubricating dispersant has good synergistic effects in molding and processing, improving the production stability and production efficiency of nylon turf yarn, and improving the quality stability of the weather-resistant and soft PA6 turf yarn material. Specific embodiments

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0023] Unless otherwise specifically stated, the numerical values set forth in these embodiments do not limit the scope of the present invention. Technologies and methods known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies and methods should be regarded as part of the specification. In all examples shown and discussed herein, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0024] In the following embodiments, the experimental methods without specific conditions are generally determined according to national standards; if there is no corresponding national standard, they are carried out according to general standard requirements or general methods.

[0025] Example 1

[0026] A weather-resistant and soft PA6 artificial turf yarn material is prepared by melt blending and extruding the following raw materials and pelletizing:

[0027] 78 kg of PA6 with a relative viscosity of 2.4, 18.4 kg of POE-g-MAH, 0.2 kg of antioxidant 1790, 0.4 kg of antioxidant 330, 0.5 kg of light stabilizer UV928, 0.5 kg of light stabilizer UV119S, and 2.0 kg of ethylene bisstearamide.

[0028] The preparation method of the weather-resistant and soft PA6 artificial turf yarn material with the above formula includes the following process:

[0029] S1. Pour the above raw materials into a mixer and mix at medium speed. The mixing temperature is 100 °C, the mixing time is 12 min, and after mixing evenly, discharge to obtain a mixed material;

[0030] S2. Feed the mixed material into a twin-screw extruder for melt blending and extrusion. The temperatures of each zone of the twin-screw extruder are: T 1 = 160 °C, T 2 = 170 °C, T 3 = 200 °C, T 4 = 210 °C, T 5 = 210 °C, T 6 = 220 °C, T7 = 230 °C, T 8 = 230 °C, T 9 = 240 °C, T 模 = 200 °C. The extruded strip enters the water tank through the die head for cooling, and is pelletized and dried by a pelletizer to obtain a weather-resistant and soft PA6 artificial turf yarn material.

[0031] Examples 2 - 6

[0032] The preparation of the PA6 artificial turf yarn materials in Examples 2 to 6 is the same as that in Example 1, except for the raw material ratio, as shown in Table 1 specifically.

[0033] Comparative Examples 1 - 2

[0034] The preparation of the PA6 artificial turf yarn materials in Comparative Examples 1 to 2 is the same as that in Example 1, except for the raw material ratio, as shown in Table 1 specifically.

[0035] Table 1 Raw material ratios of each case

[0036]

[0037] The pellets obtained in the S2 step of the above examples and comparative examples are injection molded into standard specimens by an injection molding process, and the notched impact strength of the standard specimens is tested according to the national standard. The test results are shown in Table 2.

[0038] Subsequently, the weather-resistant and soft PA6 artificial turf yarn materials of the above examples and comparative examples are extruded and drawn into nylon artificial turf yarns. The process conditions for the extrusion and drawing are as follows: The filaments are extruded through a spinneret of a single-screw extruder, cooled by a water tank, heated by a hot water tank, and stretched by using the speed difference between the first traction roller and the second traction roller, and then wound up after being guided by the third traction roller to obtain turf yarns; The process parameters of the extruder are temperature: T1 = 220 °C, T2 = 230 °C, T3 = 240 °C, T filter = 240 °C, T metering pump = 236 °C, die head = 235 °C; The pressure before the melt pump of the extruder: 6 MPa; The speed of the first traction roller is 15 m / min, the speed of the second traction roller is 52.5 m / min, the speed of the third traction roller is 52.4 m / min, and the temperature of the water tank is 95 °C.

[0039] The obtained nylon artificial turf yarns are subjected to a tensile test for PA6 artificial turf yarns according to the national standard, and the weather resistance is cyclically tested under the conditions of a light source of UVA - 340, a lamp irradiance of 1.55 W / m 2 , an irradiation time of 8 h, an irradiation temperature of 60 °C, a spraying time of 15 min, a condensation time of 3 hours and 45 minutes, and a condensation temperature of 50 °C. The test times are 1800 hours, 2200 hours, and 2500 hours respectively. The test results are shown in Table 2.

[0040] Table 2 Material Properties of Examples and Comparative Examples

[0041]

[0042] As can be seen from Table 2, by adding compatibilizers maleic anhydride grafted POE and maleic anhydride grafted LDPE to PA6, the impact strength of the modified PA6 is significantly increased, which means that the flexibility of the modified PA6 material is significantly improved, contributing to the improvement of the softness of the PA6 turf yarn and the sports comfort. Moreover, after the artificial turf monofilaments produced from the flexible weather-resistant PA6 material provided by the present invention are aged for 1800 hours, 2200 hours, and 2500 hours respectively, the retention rate of the tensile force of the artificial turf monofilaments is greater than 50%, and the retention rate of the elongation at break is greater than 30%. However, in Comparative Examples 1 to 3, fractures occurred after 1800 hours of the aging test. This shows that the flexible weather-resistant PA6 material of the present invention has good weather resistance and meets the requirements for long-term outdoor use of artificial turf.

[0043] Although there are many types of antioxidants and light stabilizers, due to their different molecular structures, the antioxidant effects and the compatibility effects of light stabilization produced by different types of antioxidants and light stabilizers in different polymer materials are completely different and vary greatly. For weather-resistant polymer materials with specific requirements, such as the PA turf yarn material that needs to be weather-resistant and soft in the present invention, specific antioxidants and light stabilizers need to be formulated and combined with the material ratio to achieve specific weather resistance effects. After many experiments, the present invention uses one of antioxidant 1790, antioxidant 330, and antioxidant 3114, and any two of UV928, UV119S, and UV660 for formulation. Combined with PA6 with a specific viscosity and a compatibilizer, it can make the PA turf yarn have excellent anti-thermal-oxidative aging and light-stabilizing aging effects during production and use.

[0044] As mentioned above, the above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered by the protection scope of the present invention.

Claims

1. A weather-resistant and soft PA6 artificial turf yarn material, characterized in that: The following raw materials in parts by weight are melt-blended, extruded and granulated: PA6 50-80 parts, lubricating dispersant 2-5 parts, toughening compatibilizer 10-25 parts, stabilizer 1-3 parts; Wherein the stabilizer comprises an antioxidant and a light stabilizer; The antioxidant consists of at least two of antioxidant 1790, antioxidant 330, and antioxidant 3114; and the light stabilizer consists of at least two of UV928, UV119S, and UV660.

2. The weather-resistant and soft PA6 artificial turf yarn material according to claim 1, characterized in that: The antioxidant is composed of antioxidant 1790 and one of antioxidant 330 and antioxidant 3114 in a mass ratio of 1:2; The light stabilizer is composed of any two of UV928, UV119S, and UV660 in an equal weight ratio.

3. The weather-resistant and soft PA6 artificial turf yarn according to claim 2, characterized in that: The relative viscosity of PA6 is 2.4 to 2.

8.

4. The weather-resistant and soft PA6 artificial turf yarn material according to claim 3, characterized in that: The lubricating dispersant is selected from at least one of zinc stearate, calcium stearate, vinyl bisstearamide and silicone powder.

5. The weather-resistant and soft PA6 artificial turf yarn material according to claim 3, characterized in that: The toughening compatibilizer is at least one of maleic anhydride grafted POE and glycidyl methacrylate grafted LDPE.

6. A method for preparing a weather-resistant and soft PA6 artificial turf yarn material, applicable to the PA6 artificial turf yarn material according to any one of claims 1 to 5, characterized in that: The steps include: S1. Evenly mix PA6, lubricating dispersant, toughening compatibilizer and stabilizer to obtain a mixed material; S2, melt-blending and extruding the mixed material, and granulating.

7. The method for preparing a weather-resistant and soft PA6 artificial turf yarn material according to claim 6, characterized in that: The mixing temperature of the mixed material is 90-110°C and the mixing time is 8-14 minutes.

8. The method for preparing a weather-resistant and soft PA6 artificial turf yarn material according to claim 6, characterized in that: The melt blending extrusion adopts a twin-screw extruder, and the temperature of each zone is: T1=150-160°C, T2=160-180°C, T3=200-230°C, T4=200-230°C, T5=200-230°C, T6=200-230°C, T7=220-240°C, T8=220-240°C, T9=220-240°C, T 模 =190~200℃.

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