Nylon material for large-diameter nylon bar and preparation method thereof

Abstract

The invention provides a nylon material for a large-diameter nylon bar and a preparation method thereof, and the nylon material comprises the following components by weight: 40%-60% of nylon 66, 10%-30% of glass fiber, 10%-30% of amorphous nylon, 3%-5% of a flexibilizer, 1.0%-1.5% of a high molecular weight lubricant, 1.0%-1.5% of a heat stabilizer, and 3%-5% of minerals. By adding a certain amount of amorphous nylon and mineral components with spherical structures, the internal stress generated in the cooling process of the large-diameter nylon bar can be reduced when the large-diameter nylon bar is produced, so that the defects of cracks, cavities, pores and the like cannot be generated in the bar, and the service life of the bar is prolonged. And the strength and the performance stability of the large-diameter nylon bar are ensured.

Description

Technical Field

[0001] The invention relates to the technical field of polymer composite materials, and in particular to a nylon material for large-diameter nylon rods and a preparation method thereof. Background Art

[0002] Polyamide, commonly known as nylon, is a linear polymer with repeating amide bonds in the molecule. It can be formed by polycondensation of dibasic acid and diamine, or by ring-opening polymerization of amino acid caprolactam. Polyamide is an engineering plastic with excellent performance, good mechanical strength, self-lubricating properties, good wear resistance, shock absorption and noise reduction, etc., and is widely used in machinery, automobiles, electrical appliances and other industries.

[0003] Nylon is an important engineering plastic. The nylon rods made from it have good mechanical properties and can replace the wear-resistant parts of mechanical equipment and replace copper or alloys as wear-resistant parts of equipment. It has good toughness, strong wear resistance, oil resistance, shock resistance, good bending strength, low water absorption, and good dimensional stability. Therefore, it is used to process various wear-resistant and high-strength parts. It is suitable for making wear-resistant parts, transmission structural parts, household appliance parts, automobile manufacturing parts, screw machinery parts, chemical machinery parts, etc., such as turbines, gears, bearings, impellers, cranks, drive shafts, valves, blades, screws, screws, nuts, shuttles, sleeves, sleeve connectors, etc.

[0004] Nylon rods are divided into two types according to different production processes: extrusion and casting. Nylon rods produced by extrusion molding generally have a smaller diameter, and their cooling process is faster and more uniform, so that the temperature difference between the inside and outside of the rod is extremely small, and it is not easy to produce voids. However, when the diameter of the nylon rod is larger, the rod will easily produce cracks, voids, pores, etc. due to crystallization shrinkage during the cooling and molding process, which seriously affects the overall strength, stability and other properties of the rod and cannot meet the use requirements. Summary of the invention

[0005] The purpose of the present invention is to provide a nylon material for large-diameter nylon rods and a preparation method thereof. By adding a certain amount of amorphous nylon and spherical structured minerals, when producing nylon rods with larger diameters, cracks, cavities, pores and other defects will not be generated inside the rods, thereby ensuring the strength and performance stability of the nylon rods with larger diameters.

[0006] To achieve the above object, the present invention proposes the following technical solutions:

[0007] A nylon material for large diameter nylon rods, comprising the following components by weight: 40%-60% nylon 66, 10%-30% glass fiber, 10%-30% amorphous nylon, 3%-5% toughening agent, 1.0%-1.5% high molecular weight lubricant, 1.0%-1.5% heat stabilizer, 3%-5% mineral,

[0008] Wherein, the structure of the mineral is a spherical structure.

[0009] As a preferred technical solution of the present invention, the nylon material includes the following components by weight percentage: 2.5% nylon 664, 15% glass fiber, 30% amorphous nylon, 5% toughening agent, 1.5% high molecular weight lubricant, 1% heat stabilizer, and 5% mineral.

[0010] As a preferred technical solution of the present invention, the high molecular weight lubricant is a high molecular weight silicone masterbatch.

[0011] As a preferred technical solution of the present invention, the heat stabilizer is a copper salt heat stabilizer.

[0012] The present invention also provides a method for preparing the nylon material for large-diameter nylon rods as described above, comprising the following steps:

[0013] Step 1: drying the nylon 66 and amorphous nylon;

[0014] Step 2: adding the dried nylon 66 and amorphous nylon, toughening agent, high molecular weight lubricant, heat stabilizer and mineral into a mixer according to weight percentage and mixing them evenly to obtain a premix;

[0015] Step 3: feeding the premix into the twin-screw extruder from the main feeding port of the twin-screw extruder, feeding the glass fiber into the twin-screw extruder from the side feeding port of the twin-screw extruder, pulling, drawing, cooling, and granulating to obtain the nylon material.

[0016] As a preferred technical solution of the present invention, the moisture content of the nylon 66 and the amorphous nylon after drying is 0.05%-0.15%.

[0017] As a preferred technical solution of the present invention, the drying temperature in step 1 is 80° C.-120° C., and the drying time is 3-5 hours.

[0018] As a preferred technical solution of the present invention, the processing parameters of the twin-screw extruder are: feeding section temperature 250°C-270°C, melting section temperature 260°C-280°C, and head section temperature 250°C-270°C.

[0019] It can be seen from the above technical scheme that the technical scheme of the present invention provides a nylon material for large-diameter nylon rods and a preparation method thereof. A certain amount of amorphous nylon is added to the nylon material component to slow down the crystallization process of the material and reduce internal stress, thereby reducing the possibility of voids and pores appearing during the crystallization shrinkage process of the material.

[0020] At the same time, high molecular weight silicone masterbatch is also added, which is mainly composed of ultra-high molecular weight siloxane polymer, which can improve the processing performance of the material in terms of lubricity and fluidity, significantly reduce the friction coefficient of the material, reduce torque, thereby reducing equipment wear, while improving the surface gloss of the material and the silky touch of the product surface, and improving its wear resistance and scratch resistance. In addition, the high molecular weight silicone masterbatch is also non-migrating, that is, it will not precipitate in the material, reducing the possibility of internal holes in the material due to the precipitation of small molecule lubricants, thereby ensuring the stability of the overall performance of the material.

[0021] In addition, the spherical minerals in the material components help to disperse the stress inside the material, which can further reduce the possibility of voids inside the material.

[0022] As is known to all, the extrusion process of large diameter nylon rods is very slow, that is, the heat will last for a long time, during which the material will degrade, and the degradation will cause pores to form inside the rod, that is, voids. Therefore, the components of the present invention also add a copper salt heat stabilizer. Compared with the ordinary antioxidant system, the special heat stabilizer can effectively reduce the degradation of the material during the extrusion process, and its effect is more prominent, thereby further reducing the possibility of voids.

[0023] It should be appreciated that all combinations of the foregoing concepts, as well as additional concepts described in greater detail below, may be considered to be part of the inventive subject matter of the present disclosure, provided such concepts are not mutually inconsistent. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs.

[0025] The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular form of "a", "an" or "the" and similar words do not indicate a quantity limitation, but indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprise" include the features, wholes, steps, operations, elements and / or components listed after "include" or "comprise", and do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0026] In order to solve the problem that existing larger diameter nylon rods are prone to defects such as cracks, voids, pores, etc. due to crystallization shrinkage during the cooling and molding process, which seriously affects the overall strength, stability and other properties of the rod and cannot meet the use requirements, an embodiment of the present invention provides a nylon material for large diameter nylon rods.

[0027] The nylon material for large-diameter nylon rods provided in an embodiment of the present invention includes the following components, measured by weight percentage: 40%-60% nylon 66, 10%-30% glass fiber, 10%-30% amorphous nylon, 3%-5% toughening agent, 1.0%-1.5% high molecular weight lubricant, 1.0%-1.5% heat stabilizer, and 3%-5% mineral.

[0028] Among them, the glass fiber can be common modified glass fiber such as alkali-free chopped glass fiber, the high molecular weight lubricant is preferably a high molecular weight silicone masterbatch, the structure of the mineral is preferably a spherical structure, such as glass beads, and the heat stabilizer is a copper salt heat stabilizer.

[0029] The embodiment of the present invention also provides a method for preparing a nylon material for a large-diameter nylon rod, which specifically comprises the following steps:

[0030] Step 1: drying the nylon 66 and the amorphous nylon; wherein the drying temperature is 80° C.-120° C., and the drying time is 3-5 hours; the moisture content of the nylon 66 and the amorphous nylon after drying is 0.05%-0.15%.

[0031] Step 2: adding the dried nylon 66 and amorphous nylon, toughening agent, high molecular weight lubricant, heat stabilizer and mineral into a mixer according to weight percentage and mixing them evenly to obtain a premix;

[0032] Step 3: feeding the premix into the main feed port of the twin-screw extruder, feeding the glass fiber into the side feed port of the twin-screw extruder, pulling, drawing, cooling, and granulating to obtain the nylon material. Preferably, the processing parameters of the twin-screw extruder are: feeding section temperature 250℃-270℃, melting section temperature 260℃-280℃, and head section temperature 250℃-270℃.

[0033] Example 1

[0034] In Example 1 of the present invention, the nylon material includes the following components by weight percentage: 2.5% nylon 664, 15% glass fiber, 30% amorphous nylon, 5% toughening agent, 1.5% high molecular weight silicone masterbatch, 1% heat stabilizer, and 5% spherical glass beads.

[0035] The method for preparing the nylon material for large-diameter nylon rods according to Example 1 of the present invention comprises the following steps:

[0036] Step 1: drying the nylon 66 and the amorphous nylon; wherein the drying temperature is 80° C.-120° C., the drying time is 3-5 hours, and the moisture content of the nylon 66 and the amorphous nylon after drying is 0.1%.

[0037] Step 2: Add the dried nylon 66 and amorphous nylon, toughening agent, high molecular weight lubricant, and thermal stabilizer mineral into a mixer according to weight percentage and mix them evenly to obtain a premix.

[0038] Step 3: Feed the premix into the main feed port of the twin-screw extruder, feed the glass fiber from the side feed port of the twin-screw extruder, haul, draw, cool, and granulate to obtain the nylon material. The processing parameters of the twin-screw extruder are: feeding section temperature 270°C-290°C, melting section temperature 260°C-280°C, and head section temperature 250°C-270°C.

[0039] Example 2

[0040] In Example 2 of the present invention, the nylon material includes the following components by weight percentage: 40% nylon 66, 10% glass fiber, 10% amorphous nylon, 3% toughening agent, 1.0% high molecular weight silicone masterbatch, 1.3% copper salt heat stabilizer, and 3% spherical glass beads.

[0041] The method for preparing the nylon material for large-diameter nylon rods according to Example 2 of the present invention comprises the following steps:

[0042] Step 1: drying the nylon 66 and the amorphous nylon; wherein the drying temperature is 80° C.-120° C., the drying time is 3-5 hours, and the moisture content of the nylon 66 and the amorphous nylon after drying is 0.08%.

[0043] Step 2: Add the dried nylon 66 and amorphous nylon, toughening agent, high molecular weight lubricant, and thermal stabilizer mineral into a mixer according to weight percentage and mix them evenly to obtain a premix.

[0044] Step 3: Feed the premix into the main feed port of the twin-screw extruder, feed the glass fiber from the side feed port of the twin-screw extruder, haul, draw, cool, and granulate to obtain the nylon material. The processing parameters of the twin-screw extruder are: feeding section temperature 270°C-290°C, melting section temperature 260°C-280°C, and head section temperature 250°C-270°C.

[0045] The performance test results of the products obtained in the above examples 1-2 are shown in Table 1.

[0046] Table 1 Test results of various properties of products in Example 1-2

[0047]

[0048] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A nylon material for large diameter nylon rods, characterized in that: According to weight percentage, it includes the following components: nylon 6640%-60%, glass fiber 10%-30%, amorphous nylon 10%-30%, toughening agent 3%-5%, high molecular weight lubricant 1.0%-1.5%, heat stabilizer 1.0%-1.5%, mineral 3%-5%; Wherein, the structure of the mineral is a spherical structure.

2. The nylon material for large diameter nylon rods according to claim 1, characterized in that: The nylon material comprises the following components by weight percentage: 2.5% nylon 664, 15% glass fiber, 30% amorphous nylon, 5% toughening agent, 1.5% high molecular weight lubricant, 1% heat stabilizer, and 5% mineral.

3. The nylon material for large diameter nylon rods according to claim 1, characterized in that: The high molecular weight lubricant is a high molecular weight silicone masterbatch.

4. The nylon material for large diameter nylon rods according to claim 1, characterized in that: The heat stabilizer is a copper salt heat stabilizer.

5. A method for preparing nylon material for large diameter nylon rods as claimed in claims 1 to 4, characterized in that: The following steps are involved: Step 1: drying the nylon 66 and amorphous nylon; Step 2: adding the dried nylon 66 and amorphous nylon, toughening agent, high molecular weight lubricant, heat stabilizer and mineral into a mixer according to weight percentage and mixing them evenly to obtain a premix; Step 3: feeding the premix into the twin-screw extruder from the main feeding port of the twin-screw extruder, feeding the glass fiber into the twin-screw extruder from the side feeding port of the twin-screw extruder, pulling, drawing, cooling, and granulating to obtain the nylon material.

6. The method for preparing nylon material for large diameter nylon rods according to claim 5, characterized in that: The moisture content of the dried nylon 66 and the amorphous nylon is 0.05%-0.15%.

7. The method for preparing nylon material for large diameter nylon rods according to claim 5, characterized in that: The drying temperature in step 1 is 80° C.-120° C., and the drying time is 3-5 hours.

8. The method for preparing nylon material for large diameter nylon rods according to claim 5, characterized in that: The processing parameters of the twin-screw extruder are: feeding section temperature 250°C-270°C, melting section temperature 260°C-280°C, and head section temperature 250°C-270°C.

Images