High-performance plastic alloy and preparation method thereof

Abstract

According to the high-performance plastic alloy and the preparation method thereof, polyethylene, polypropylene, polyester and the like which are low in price are adopted as raw materials, reasonable composition is adopted, and the high-performance plastic alloy is prepared by combining a one-step extrusion granulation process with improved procedures of segmented temperature control conveying and water tank temperature control locking crystallization. The plastic alloy with excellent mechanical properties such as high strength, high toughness and the like is prepared, the plastic alloy also has excellent wear resistance, cold resistance, aging resistance and the like, the main physical indexes of the plastic alloy reach or exceed those of common ABS resin, and the plastic alloy has the capability of replacing part of application scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic alloys, and particularly to a high-performance plastic alloy and a preparation method thereof. Background Art

[0002] Plastic alloys are a class of new materials with high performance, functionality, and specialization obtained by physical blending or chemical grafting methods. Plastic alloy products can be widely used in fields such as automobiles, electronics, precision instruments, office equipment, packaging materials, and building materials. It can improve or enhance the performance of existing plastics and reduce costs, and has become one of the most active varieties in the plastic industry. For example, ABS plastic is currently the most commonly used plastic alloy. However, the raw material price of ABS is high, and some of its properties can only meet partial functional requirements. Therefore, it is very necessary to develop plastic alloys with low raw material prices and low preparation costs to replace the relatively expensive ABS plastic alloy. Summary of the Invention

[0003] Therefore, based on the above background, the present invention provides a high-performance plastic alloy and a preparation method thereof. It uses low-cost polyethylene, polypropylene, and polyester as raw materials, has a simple preparation process, and has wear resistance, cold resistance, anti-aging properties, and high mechanical properties, and can meet more requirements.

[0004] The technical solution of the present invention is as follows:

[0005] A high-performance plastic alloy, the weight ratio of its preparation raw materials is as follows:

[0006] Nylon 15 - 35%;

[0007] Polyester 15 - 30%;

[0008] Polyethylene 8 - 25%;

[0009] Polypropylene 20 - 28%;

[0010] Auxiliary agent 1 - 5%.

[0011] Preferably, the weight ratio of its preparation raw materials is as follows:

[0012] Nylon 30%;

[0013] Polyester 25%;

[0014] Polyethylene 15%;

[0015] Polypropylene 28%;

[0016] Auxiliary agent 2%.

[0017] Preferably, the auxiliary agent is composed of maleic anhydride, nucleating agent, magnesium dihydroxystearate, and plasticizer.

[0018] Preferably, the component weight ratio of the auxiliary agent is as follows:

[0019] Maleic anhydride 20-30%, nucleating agent 5-15%, magnesium dihydroxystearate 10-30%, plasticizer 40-55%.

[0020] Preferably, the component weight ratio of the auxiliary agent is as follows:

[0021] Maleic anhydride 25%, nucleating agent 10%, magnesium dihydroxystearate 15%, plasticizer 50%.

[0022] Preferably, the nucleating agent is selected from at least one of talcum powder and silica.

[0023] Preferably, the plasticizer is selected from phthalates or phosphates.

[0024] Based on the same inventive concept, the present invention also provides a method for preparing a high-performance plastic alloy, comprising the following steps:

[0025] S1: Weigh nylon, polyester, polyethylene, and polypropylene according to the amount and mix and stir them;

[0026] S2: Weigh the auxiliary agent according to the amount, add it to the material mixed in step S1, stir evenly and carry out physical and chemical treatment, and then stand for curing;

[0027] S3: Feed the cured mixed material into a twin-screw extruder through the feed port, and after initial melting, heat-resistant crystallization, heat preservation conveying, cooling conveying, and extrusion and drawing, lock and crystallize the drawn wire through a water tank, and then pelletize;

[0028] Preferably, the temperature parameters of each section of the twin-screw extruder in step S3 are as follows:

[0029] Temperature of the first section: 0-25°C;

[0030] Temperature of the second section: 200-250°C;

[0031] Temperature of the third to sixth sections: 220-280°C;

[0032] Temperature of the seventh to ninth sections: 230-250°C;

[0033] Temperature of the tenth to eleventh sections: 220-260°C;

[0034] Temperature of the twelfth section: 210-245°C.

[0035] Preferably, the temperature of the water tank in step S3 is 20-35°C.

[0036] The beneficial effects achieved by adopting the present invention are as follows:

[0037] The present invention uses low-cost polyethylene, polypropylene, polyester, etc. as raw materials. Through reasonable composition and combination with a one-step extrusion granulation process that improves the processes of segmented temperature-controlled conveying and water tank temperature-controlled locking crystallization, a plastic alloy is prepared that not only has excellent mechanical properties such as high strength and high toughness, but also has excellent wear resistance, cold resistance, and anti-aging properties. Its main physical indicators reach or exceed those of general ABS resins, and it has the ability to replace some application scenarios. Brief Description of the Drawings

[0038] Appendix Figure 1 It is a schematic diagram of the functions of each section of the twin-screw extruder of the present invention.

[0039] Appendix Figure 2 It is the plastic alloy masterbatch prepared by the present invention. Detailed Embodiments

[0040] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further elaborates on the present invention in combination with its embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] The experimental methods used in the following embodiments are all conventional methods unless otherwise specified.

[0042] The materials, reagents, etc. used in the following embodiments can all be obtained from commercial channels unless otherwise specified.

[0043] Embodiment 1: A high-performance plastic alloy, and the weight ratio composition of its preparation raw materials is as follows:

[0044] Nylon PA 30%;

[0045] Polyester PET 25%;

[0046] Polyethylene PE 15%;

[0047] Polypropylene PP 28%;

[0048] Additive 2%.

[0049] The weight ratio composition of the components of the additive is as follows:

[0050] Maleic anhydride 25%, nucleating agent 10%, magnesium dihydroxystearate 15%, plasticizer 50%.

[0051] In this embodiment, the nucleating agent is selected from talcum powder.

[0052] The plasticizer is selected from phosphate esters, specifically triphenyl phosphate, and also has a flame retardant function.

[0053] The nylon type of the present invention can be selected from at least one of PA6, PA66, PA11, PA12, PA46, PA610, PA612 and PA1010. In this embodiment, PA66 is selected, and specifically, PA66 is purchased from Shenma EPR27 of China Shenma Industry Co., Ltd.

[0054] In this embodiment, the polyester PET is selected as DuPont FR515;

[0055] In this embodiment, the molecular weight of the polyethylene is 250,000 - 500,000.

[0056] In this embodiment, the molecular weight of the polypropylene is 80,000 - 120,000.

[0057] Its preparation process includes the following steps:

[0058] S1: Weigh nylon, polyester, polyethylene, and polypropylene and mix them in a mixer, then stir at a low speed (100 - 200 revolutions per minute) for 2 minutes;

[0059] S2: Weigh the additives, add them to the mixture obtained in step S1, then stir at a low speed (100 - 200 revolutions per minute) for 2 minutes and then at a high speed (1200 - 1500 revolutions per minute) for 3 minutes to make it uniformly physical and chemical, and let it stand and solidify for 1 minute;

[0060] S3: Feed the solidified mixed material into a twin - screw extruder through the feed inlet, and then through primary melting, heat - resistant stable crystallization, heat - preservation transportation, cooling transportation, extrusion and drawing. After the extruded drawing is locked and crystallized in a water bath at 20 - 35°C, pelletize it to prepare the masterbatch;

[0061] The temperature parameters of each section of the twin - screw extruder in this step are as follows (the functions of each section can be seen in the attached Figure 1 shown, through primary melting in the second section, heat - resistant stable crystallization in the third to sixth sections, heat - preservation transportation in the seventh to ninth sections, and cooling transportation in the tenth to eleventh sections):

[0062] Temperature of the first section: 0°C;

[0063] Temperature of the second section: 230°C;

[0064] Temperatures of the third to sixth sections: 260°C;

[0065] Temperatures of the seventh to ninth sections: 245°C;

[0066] Temperatures of the tenth to eleventh sections: 240°C;

[0067] Temperature of the twelfth section: 230°C.

[0068] The cost of preparing the plastic alloy masterbatch in this embodiment is calculated. After measurement, the estimated cost of the alloy material is about 12,000 yuan, while the domestic selling price of ABS generally ranges from 17,000 yuan to 21,000 yuan.

[0069] The plastic alloy masterbatch prepared in Example 1 was injection-molded into samples, and the properties of the samples were tested. The test results are shown in Table 1.

[0070] Injection molding conditions: Drying temperature: 128 °C; Drying time: 240 min; Injection temperature: 250 °C; Injection pressure: 65 MPa; Weight of the sample plate: 31.67 g;

[0071] Table 1: Performance test results

[0072]

[0073] The anti-aging performance of the above samples was tested and submitted to SGS for testing. The test report number is: TJIN2107010442MR-CN. Test items: Photoaging test - Ultraviolet radiation exposure. Test method: GB / T 14522-2008 cycle & ASTM E313-20.

[0074] Test conditions:

[0075] Test cycle:

[0076] GBT 14522-2008 cycle 1

[0077] Lamp type: UVA-340

[0078] Light exposure: 8 h, (60 + 3) °C BPT, 0.89 W / (m2nm) @ 340 nm

[0079] Condensation: 4 h, (50 ± 3) °C BPT

[0080] Exposure time: 48 hours.

[0081] Result: YI: 23.2.

[0082] And a series of ABS products (PA-757K) of a certain American company were purchased and blow-molded into samples in the same way as in Example 1, and the properties of the samples were tested. The tensile strength was 46 Mpa, the elongation at break was 20%, and the impact strength was 18 KJ / m 2 。

[0083] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A high performance plastic alloy, characterized in that: The weight ratio of the raw materials used in its preparation is as follows: Nylon 15-35%; Polyester 15-30%; Polyethylene 8-25%; Polypropylene 20-28%; Additives 1-5%.

2. A high performance plastic alloy according to claim 1, characterized in that: The weight ratio of the raw materials used in its preparation is as follows: Nylon 30%; Polyester 25%; Polyethylene 15%; Polypropylene 28%; Auxiliary agent 2%.

3. A high performance plastic alloy according to claim 1 or 2, characterized in that: The auxiliary agent consists of malic anhydride, a nucleating agent, dihydroxy magnesium stearate and a plasticizer.

4. A high performance plastic alloy according to claim 3, characterized in that: The weight ratio of the ingredients of the auxiliary agent is as follows: Malic anhydride 20-30%, nucleating agent 5-15%, dihydroxy magnesium stearate 10-30%, plasticizer 40-55%.

5. A high performance plastic alloy according to claim 4, characterized in that: The weight ratio of the ingredients of the auxiliary agent is as follows: Malic anhydride 25%, nucleating agent 10%, dihydroxy magnesium stearate 15%, plasticizer 50%.

6. A high performance plastic alloy according to claim 3, characterized in that: The nucleating agent is selected from at least one of talc and silicon dioxide.

7. A high performance plastic alloy according to claim 3, characterized in that: The plasticizer is selected from phthalates or phosphates.

8. The method for preparing a high performance plastic alloy according to any one of claims 1 to 7, characterized in that: The steps include: S1: Take nylon, polyester, polyethylene and polypropylene according to the amount and mix them; S2: taking an amount of auxiliary agent, adding it to the material mixed in step S1, stirring it evenly, and then standing it to solidify; S3: The solidified mixed material is fed into the twin-screw extruder through the feed port and then goes through initial melting, stabilization of crystal shape, heat preservation conveying, cooling conveying, extrusion and drawing. The extruded drawing is passed through a water tank for locking and crystallization, and then pelletized.

9. The method for preparing a high performance plastic alloy according to claim 8, characterized in that: The temperature parameters of each section of the twin-screw extruder in step S3 are as follows: One temperature: 0-25℃; Second stage temperature: 200-250℃; Temperature of the third to sixth stage: 220-280℃; Temperature from stage 7 to stage 9: 230-250℃' Temperature from stage 10 to stage 11: 220-260℃; Twelve temperature stages: 210-245°C.

10. The method for preparing a high performance plastic alloy according to claim 9, characterized in that: The temperature of the water tank in step S3 is 20-35°C.

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