A laser-engravable high-strength polyamide 6 composition and preparation method thereof

Abstract

The invention discloses a high-strength polyamide 6 composition capable of laser engraving, which is prepared by the following components in parts by weight: 55-70 parts of PA6 resin, 30 parts of glass fiber, 0.5 parts of antioxidant, 0.5 parts of lubricant, 0.2-2 parts of colorant, and 0.5-3 parts of functional additive; wherein the functional additive is one of black engraving and white laser engraving powder, ultrafine calcium carbonate, antimony trioxide, and anhydrous lithium chloride. The invention uses polyamide 6 resin as a base material, and then fully mixes it with an antioxidant, a lubricant, a black masterbatch, and a functional host premix, and finally introduces glass fiber into the side feed, so that the invention has high strength and clear laser engraving characteristics.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a laser-engravable high-strength polyamide 6 composition and a preparation method thereof. Background Art

[0002] Polyamide resin has excellent comprehensive mechanical properties, good fluidity, high mechanical strength, good corrosion resistance, and good wear resistance, self-lubrication and electrical insulation, making it widely used in the automotive and home appliance fields. Since the mechanical strength of polyamide 6 resin raw materials is not very high, many high-strength products cannot meet the requirements. In this case, its strength can be improved by glass fiber reinforcement to meet the strength requirements of various parts and components, expanding the application range of polyamide 6. However, during the production process, the product model and batch information marked on plastic products with labels or markers are prone to fall off or fade, making it difficult to correctly identify the product information.

[0003] Injection molding factories often find that the markings such as product model and batch on plastic products have fallen off or faded, and they cannot correctly identify the specific information of the parts in a short time. There is also a situation where after the downstream complains, it is impossible to trace the source. The laser engraving process can solve the above problems. Therefore, it is imperative to improve the laser engraving properties of polyamide 6 materials while ensuring high strength performance. Summary of the invention

[0004] In view of this, the present invention provides a high-strength polyamide 6 composition capable of laser engraving and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology and prepare a polyamide 6 material with high strength performance and laser engraving clarity.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] On the one hand, the present invention discloses a laser-engravable high-strength polyamide 6 composition, which is prepared from the following components in parts by weight:

[0007]

[0008]

[0009] Wherein, the functional additive is one of black carving white laser carving powder, ultrafine calcium carbonate, antimony trioxide, and anhydrous lithium chloride.

[0010] As a further solution of the present invention: the relative viscosity of the polyamide 6 resin is 2.7±0.03.

[0011] As a further solution of the present invention: the glass fiber is a chopped glass fiber with a silane-based sizing agent coated on the surface, the chopped length is 3.0-4.5 mm, and the fiber diameter is 12-14 μm.

[0012] As a further embodiment of the present invention: the antioxidant is at least one of N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine and tris[2,4-di-tert-butylphenyl]phosphite.

[0013] As a further solution of the present invention: the lubricant is NN-hexylene bis-hard amide.

[0014] As a further solution of the present invention: the colorant is at least one of 40wt% carbon black masterbatch with PA6 as carrier, 40wt% aniline black masterbatch with PA6 as carrier, thermal cracking carbon black powder and gas-process carbon black powder.

[0015] Another aspect of the present invention discloses a method for preparing the laser-engravable high-strength polyamide 6 composition as described above, comprising the following steps:

[0016] The antioxidant, lubricant, black masterbatch and functional additives are mixed evenly with a high-speed mixer, and then mixed evenly with the pre-dried PA6 resin, and then added to the main feeding barrel of the twin-screw extruder. Then, glass fiber is added from the side feeding port of the twin-screw extruder. After melting, extrusion, cooling, air drying and pelletizing, a high-strength polyamide 6 composition that can be laser engraved is obtained.

[0017] As a further solution of the present invention: the temperature of zone 1 of the twin-screw extruder is 180-200°C, the temperature of zones 2 to 5 is 240-250°C, the temperature of zones 6 to 9 is 230-240°C, the head temperature is 240-250°C, and the screw speed is 400rpm.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The present invention uses polyamide 6 resin as the base material, and then fully mixes it with antioxidants, lubricants, black masterbatches, and functional host premixes, and finally introduces glass fibers through side feeding, so that the present invention has high strength and clear laser engraving characteristics.

[0020] 2. The preparation method of the present invention is simple, the obtained material is pollution-free, and is easy for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The actual effect diagram of the laser engraving process of the compositions obtained in the examples and comparative examples; DETAILED DESCRIPTION

[0022] For ease of understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0024] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0025] PA6 resin, its manufacturer is Yueyang Petrochemical, brand name is YH800;

[0026] Glass fiber, the manufacturer is China Jushi, the brand is ECS10-03-568H;

[0027] Antioxidant, the manufacturer is BASF, brand number is 1098;

[0028] Lubricant: NN-hexylene bis-hard amide, manufactured by Japan Kao, brand EB-FF;

[0029] Colorants:

[0030] Black masterbatch A: Black masterbatch is 40wt% carbon black masterbatch in PA6 carrier;

[0031] Black masterbatch B: 40wt% aniline black masterbatch based on PA6 carrier;

[0032] Black masterbatch C-1: thermal cracking carbon black powder;

[0033] Black masterbatch C-2: gas-process carbon black powder.

[0034] Functional additives:

[0035] Functional additive A: The manufacturer of black carving and white laser carving powder is Merck of Germany, with the brand number 8835;

[0036] Functional additive B: The manufacturer of ultrafine calcium carbonate is Jiangsu Qunxin, brand number is 053B;

[0037] Functional additive C: Antimony trioxide is produced by Hunan Chenzhou Mining Co., Ltd.

[0038] Functional additive D: Anhydrous lithium chloride (LiCl) is produced by Sveto and its brand name is Sveto17.

[0039] All materials are commercially available common products.

[0040] It is to be understood that the above raw materials and reagents are only examples of some specific embodiments of the present invention, so that the technical solution of the present invention is clearer, and it does not mean that the present invention can only use the above reagents, and the specific scope in the claims shall prevail. In addition, the "parts" described in the examples and comparative examples, unless otherwise specified, refer to parts by weight.

[0041] Any range described in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0042] Examples 1-6 and Comparative Examples 1-2 were prepared according to the following steps:

[0043] Weigh each component according to the ratio in Table 1, mix the antioxidant, lubricant, colorant and functional additive evenly with a high-speed mixer, mix evenly with the pre-dried polyamide 6 resin, add it to the main feeding barrel of the twin-screw extruder, and then add glass fiber from the side feeding port of the twin-screw extruder, melt, extrude, cool, air-dry, and pelletize to obtain a polyamide 6 composition that can be laser-engraved, wherein the temperature of zone 1 of the twin-screw extruder is 190°C, the temperature of zone 2 is 240°C, the temperature of zones 3 to 5 is 250°C, the temperature of zones 6 to 9 is 230°C, the head temperature is 250°C, and the screw speed is 400rpm.

[0044] Table 1

[0045]

[0046] The polyamide 6 compositions obtained in the above examples 1-6 and comparative examples 1-2 were injection molded into national standard specimens and high gloss plates at an injection molding temperature of 245-260°C, and performance tests and laser engraving experiments were performed. The laser engraving equipment was a Suzhou Little Giant laser marking machine with the following parameters: laser wavelength 1064nm, focal length 221mm, laser engraving speed 1500mm / s, laser engraving frequency 20Hz, and laser engraving power 7.5W. The test results are shown in Tables 2 and Figure 1 .

[0047] Table 2 Test results

[0048]

[0049]

[0050] Note: The tensile strength is tested according to ISO 527 standard at a speed of 5mm / min. In the evaluation standard of laser engraving clarity, the more *, the clearer the laser engraving effect, and the whiter the laser engraving color, the better the effect.

[0051] From Table 1, Table 2 and Figure 1It can be seen that the introduction of aniline black masterbatch is not conducive to laser engraving; the carbon black masterbatch has a poor laser engraving effect compared with carbon black powder, and among carbon black powders, the solution using thermal cracking carbon black has better laser engraving effect than gas-process carbon black; several functional additives can improve the clarity of laser engraving, especially the introduction of anhydrous LiCl, which significantly improves the clarity of material laser engraving and the color of laser engraving is the whitest.

[0052] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0053] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. A laser-engravable high-strength polyamide 6 composition, characterized in that: It is prepared from the following components in parts by weight: Wherein, the functional additive is anhydrous lithium chloride; The colorant is at least one of thermal cracking carbon black powder and gas-process carbon black powder.

2. The laser-engravable high-strength polyamide 6 composition according to claim 1, characterized in that: The relative viscosity of the polyamide 6 resin is 2.7±0.

03.

3. The laser-engravable high-strength polyamide 6 composition according to claim 1, characterized in that: The glass fiber is a short-cut glass fiber with a silane-based sizing agent coated on the surface, with a short-cut length of 3.0-4.5 mm and a fiber diameter of 12-14 μm.

4. The laser-engravable high-strength polyamide 6 composition according to claim 1, characterized in that: The antioxidant is at least one of N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine and tris[2,4-di-tert-butylphenyl]phosphite.

5. The laser-engravable high-strength polyamide 6 composition according to claim 1, characterized in that: The lubricant is NN-hexylene bis-hard amide.

6. The method for preparing the laser-engravable high-strength polyamide 6 composition according to any one of claims 1 to 5, characterized in that: The following steps are involved: The antioxidant, lubricant, colorant and functional additive are mixed evenly with a high-speed mixer, and then mixed evenly with the pre-dried PA6 resin, and then added to the main feeding barrel of the twin-screw extruder. Then, glass fiber is added from the side feeding port of the twin-screw extruder. After melting, extrusion, cooling, air drying and pelletizing, a high-strength polyamide 6 composition that can be laser engraved is obtained.

7. The preparation method according to claim 6, characterized in that: The temperature of zone 1 of the twin-screw extruder is 180-200°C, the temperature of zones 2 to 5 is 240-250°C, the temperature of zones 6 to 9 is 230-240°C, the head temperature is 240-250°C, and the screw speed is 400rpm.

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