A preparation method of high-strength PA alloy plastic material

Abstract

The present invention relates to the technical field of nylon alloys and discloses a method for preparing a high-strength PA alloy plastic material. The method comprises the following steps: mixing nylon 6, polyphenylene ether, polyphenylene ether amide, an antioxidant, and an auxiliary agent, placing the mixture in a twin-screw extruder, and performing melt extrusion and granulation to obtain the high-strength PA alloy plastic material; and subjecting 2,6-dimethyl-p-phenylenedi(oxyethylamine) to a polymerization reaction with succinyl chloride and the like to obtain polyphenylene ether amide. The polyphenylene ether amide contains a 2,6-dimethyl-p-phenylenedi(oxyethylamine) structural unit similar to polyphenylene ether and an amide bond structural unit similar to nylon 6. This allows the polyphenylene amide to serve as a compatibilizer, thereby enhancing the interfacial interaction between nylon 6 and polyphenylene ether and improving the compatibility between the two. This results in a PA / PPE alloy composite plastic material with better mechanical properties, exhibiting higher flexural strength, impact strength, tensile strength, and elongation at break.

Description

Technical Field

[0001] The present invention relates to the technical field of nylon alloys, and in particular to a method for preparing a high-strength PA alloy plastic material. Background Art

[0002] Nylon 6 is a polyamide polymer material with a low melting point, a wide processing temperature range, good hygroscopicity, and excellent wear resistance. It is widely used in automotive parts, electronic appliances, cable sheathing, and other fields. Polyphenylene ether is a high-performance polymer prepared primarily using 2,6-dimethylphenol as a monomer through oxidative coupling. It exhibits strong electrical insulation, excellent water resistance, good wear resistance, and high dimensional stability.

[0003] Combining nylon 6 with polyphenylene ether (PPE) can yield an alloy material with excellent properties. However, the compatibility between nylon 6 and PPE is poor, typically requiring the addition of a compatibilizer such as maleic anhydride-grafted POE, maleic anhydride-grafted SEBS, carboxylated polystyrene, or styrene-glycidyl methacrylate. Developing a compatibilizer for nylon 6 and PPE is a research challenge. Summary of the Invention

[0004] (1) Technical Problem to be Solved: The present invention provides a PA alloy plastic material with high strength and good toughness.

[0005] (II) Technical Solution: A method for preparing a high-strength PA alloy plastic material comprises the following steps:

[0006] Step (1): Place the reaction vessel in an ice-water bath, add N,N-dimethylformamide, 2,6-dimethylphenylenedi(oxyethylamine), and triethylamine, stir, and dropwise add the diacyl chloride compound. Stir and react at 40-60° C. for 12-18 hours. Pour the solution into ethanol for precipitation. After filtering, wash with water and ethanol in sequence, and dry to obtain polyphenylene ether amide. The reaction formula is:

[0007]

[0008] Step (2): nylon, polyphenylene ether, polyphenylene ether amide, antioxidant and additive are mixed and placed in a twin-screw extruder with each section temperature at 245-265°C and the head temperature at 260°C, and melt-extruded and granulated to obtain a high-strength PA alloy plastic material.

[0009] Furthermore, in step (1), the molar ratio of 2,6-dimethylphenylenedi(oxyethylamine), triethylamine, and diacyl chloride compound is 1:(2.2-2.6):(0.9-1.1).

[0010] Furthermore, the diacyl chloride compound is succinyl chloride, glutaryl chloride or adipoyl chloride.

[0011] Furthermore, in step (2), the mass ratio of nylon 6, polyphenylene ether, and polyphenylene ether amide is (30-50):(50-70):(1.5-5).

[0012] Furthermore, in step (2), the antioxidant is antioxidant 1010, antioxidant 168 or antioxidant 1098; and the auxiliary agent is calcium stearate or zinc stearate.

[0013] Further, the preparation method of 2,6-dimethylphenylenedi(oxyethylamine) is:

[0014] (1) Add N,N-dimethylformamide, 2,6-dimethylhydroquinone in a molar ratio of 1:(2.6-3.2):(5-6), 2-(Boc-amino) bromoethane, and potassium carbonate to a reaction vessel, heat to 80-90°C, stir and react for 18-24 hours, add water, and then extract with dichloromethane. The dichloromethane organic phase is dried over anhydrous sodium sulfate, filtered, and the filtrate is rotary evaporated, washed with petroleum ether, and dried to obtain an intermediate.

[0015] (2) Add dichloromethane, trifluoroacetic acid (16-20):1, and the intermediate to the reaction vessel, react at room temperature for 2-3 hours, rotary evaporate, wash with 5% sodium carbonate solution, and dry to obtain 2,6-dimethylphenylenedi(oxyethylamine). The reaction formula is as follows:

[0016]

[0017] (III) Technical Effect: The present invention conducts an etherification reaction between 2,6-dimethylhydroquinone and 2-(Boc-amino)ethyl bromide and removes the Boc protecting group to obtain 2,6-dimethylphenylenedi(oxyethylamine), which is then polymerized with succinyl chloride and the like to obtain polyphenylene ether amide, which contains a 2,6-dimethylphenylene diether structural unit similar to polyphenylene ether and an amide bond structural unit similar to nylon 6, so that polyphenylene amide can be used as a compatibilizer to enhance the interfacial interaction between nylon 6 and polyphenylene ether and improve the compatibility between the two, thereby obtaining a PA / PPE alloy composite plastic material with better mechanical properties, exhibiting higher flexural strength, impact strength, tensile strength and elongation at break. DETAILED DESCRIPTION

[0018] In order to understand the technical features and content of the present invention in detail, the preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described in the embodiments, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein.

[0019] The nylon 6 of the present invention, model PA6M2800, is available from Shanghai Hehongcheng Plastic Technology Co., Ltd.; polyphenylene ether, model LXN050, is available from Nantong Xingchen Synthetic Materials Co., Ltd.; maleic anhydride-grafted POE, model XY-310, is available from Dongguan Xingyuan Chemical Co., Ltd.; and maleic anhydride-grafted SEBS, model XYJ12902, is available from Dongguan Xingyuan Chemical Co., Ltd.

[0020] Example 1:

[0021] (1) Add 8 mL of N,N-dimethylformamide, 5 mmol of 2,6-dimethylhydroquinone, 13 mmol of 2-(Boc-amino)bromoethane, and 30 mmol of potassium carbonate to a reaction vessel, heat to 90°C, stir and react for 18 hours, add water, and then extract with dichloromethane. The dichloromethane organic phase is dried over anhydrous sodium sulfate, filtered, and the filtrate is rotary evaporated, washed with petroleum ether, and dried to obtain an intermediate.

[0022] (2) Add 70 mL of dichloromethane, 400 mmol of trifluoroacetic acid, and 20 mmol of the intermediate to the reaction vessel, react at room temperature for 2 h, rotary evaporate, wash with 5% by mass sodium carbonate solution, and dry to obtain 2,6-dimethylphenylenedi(oxyethylamine).

[0023] (3) Place the reaction vessel in an ice-water bath, add 400 mL of N,N-dimethylformamide, 100 mmol of 2,6-dimethylphenylenedi(oxyethylamine), and 260 mmol of triethylamine, stir, and dropwise add 100 mmol of succinyl chloride. Stir and react at 60°C for 12 hours. Pour the solution into ethanol for precipitation, filter, wash with water and ethanol in turn, and dry to obtain polyphenylene ether amide.

[0024] (4) 300g of nylon 6, 700g of polyphenylene ether, 15g of polyphenylene ether amide, 5g of antioxidant 1010, and 22g of the auxiliary agent calcium stearate were mixed and placed in a twin-screw extruder with the temperatures of each section being 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature being 260°C. The mixture was melt-extruded and granulated to obtain a high-strength PA alloy plastic material.

[0025] Example 2:

[0026] (1) Add 10 mL of N,N-dimethylformamide, 5 mmol of 2,6-dimethylhydroquinone, 16 mmol of 2-(Boc-amino)bromoethane, and 25 mmol of potassium carbonate to a reaction vessel, heat to 80°C, stir and react for 24 hours, add water, and then extract with dichloromethane. The dichloromethane organic phase is dried over anhydrous sodium sulfate, filtered, and the filtrate is rotary evaporated, washed with petroleum ether, and dried to obtain an intermediate.

[0027] (2) Add 60 mL of dichloromethane, 320 mmol of trifluoroacetic acid, and 20 mmol of the intermediate into the reaction vessel, react at room temperature for 3 h, rotary evaporate, wash with 5% by mass sodium carbonate solution, and dry to obtain 2,6-dimethylphenylenedi(oxyethylamine).

[0028] (3) Place the reaction vessel in an ice-water bath, add 400 mL of N,N-dimethylformamide, 100 mmol of 2,6-dimethylphenylenedi(oxyethylamine), and 260 mmol of triethylamine, stir, and dropwise add 110 mmol of glutaryl chloride. Stir and react at 40°C for 18 hours. Pour the solution into ethanol for precipitation, filter, wash with water and ethanol in turn, and dry to obtain polyphenylene ether amide.

[0029] (4) Mix 400g nylon 6, 600g polyphenylene ether, 15g polyphenylene ether amide, 6g 1098, and 28g additive zinc stearate, place them in a twin-screw extruder, set the temperatures of each section at 245℃, 250℃, 260℃, 260℃, and 255℃, and the head temperature at 260℃, melt extrude and granulate to obtain a high-strength PA alloy plastic material.

[0030] Example 3:

[0031] (1) Place the reaction vessel in an ice-water bath, add 300 mL of N,N-dimethylformamide, 100 mmol of 2,6-dimethylphenylenedi(oxyethylamine) (prepared by Example 2), and 220 mmol of triethylamine, stir, and dropwise add 90 mmol of adipoyl chloride. Stir and react at 45°C for 18 hours. Pour the solution into ethanol for precipitation, filter, wash with water and ethanol in sequence, and dry to obtain polyphenylene ether amide.

[0032] (2) 500g of nylon 6, 500g of polyphenylene ether, 15g of polyphenylene ether amide, 5.2g of antioxidant 168, and 15g of auxiliary agent calcium stearate were mixed and placed in a twin-screw extruder with the temperatures of each section being 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature being 260°C. The mixture was melt-extruded and granulated to obtain a high-strength PA alloy plastic material.

[0033] Example 4:

[0034] (1) 400 g of nylon 6, 600 g of polyphenylene ether, 30 g of polyphenylene ether amide (prepared by Example 2), 6 g of 1098, and 28 g of the additive zinc stearate were mixed and placed in a twin-screw extruder with the temperatures of each section at 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature at 260°C. The mixture was melt-extruded and granulated to obtain a high-strength PA alloy plastic material.

[0035] Example 5:

[0036] (1) 400g of nylon 6, 600g of polyphenylene ether, 50g of polyphenylene ether amide (prepared by Example 2), 6g of 1098, and 28g of the auxiliary agent zinc stearate were mixed and placed in a twin-screw extruder with the temperatures of each section at 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature at 260°C. The mixture was melt-extruded and granulated to obtain a high-strength PA alloy plastic material.

[0037] Comparative Example 1:

[0038] (1) 300g nylon 6, 700g polyphenylene ether, 5g antioxidant 1010, and 22g auxiliary agent calcium stearate were mixed and placed in a twin-screw extruder with the temperatures of each section at 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature at 260°C. The mixture was melt-extruded and granulated to obtain PA alloy plastic material.

[0039] Comparative Example 2:

[0040] (1) Place the reaction vessel in an ice-water bath, add 400 mL of N,N-dimethylformamide, 100 mmol of 1,4-phenylenediamine, and 260 mmol of triethylamine, stir, and dropwise add 100 mmol of succinyl chloride. Stir and react at 60°C for 12 hours. Pour the solution into ethanol for precipitation. After filtering, wash with water and ethanol in turn, and dry to obtain polyphenylamide.

[0041] (2) 300g nylon 6, 700g polyphenylene ether, 15g polyphenylamide, 5g antioxidant 1010, and 22g auxiliary agent calcium stearate were mixed and placed in a twin-screw extruder with the temperatures of each section being 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature being 260°C. The mixture was melt-extruded and granulated to obtain a PA alloy plastic material.

[0042] Comparative Example 3:

[0043] (1) 300g nylon 6, 700g polyphenylene ether, 15g maleic anhydride grafted POE (ethylene-octene copolymer), 5g antioxidant 1010, and 22g auxiliary agent calcium stearate were mixed and placed in a twin-screw extruder with the temperatures of each section at 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature at 260°C. The mixture was melt-extruded and granulated to obtain PA alloy plastic material.

[0044] Comparative Example 4:

[0045] (2) 300g of nylon 6, 700g of polyphenylene ether, 15g of maleic anhydride grafted SEBS (hydrogenated styrene-butadiene block copolymer), 5g of antioxidant 1010, and 22g of auxiliary agent calcium stearate were mixed and placed in a twin-screw extruder with the temperatures of each section at 245°C, 250°C, 260°C, 260°C, and 255°C, and the head temperature at 260°C. The mixture was melt-extruded and granulated to obtain a PA alloy plastic material.

[0046] The PA alloy plastic material is injection molded by an injection molding machine to produce a standard specimen.

[0047] The bending properties were tested according to GB / T9341-2000. The impact properties were tested according to GB / T1843-2008. The tensile properties were tested according to GB / T1040.1-2018.

[0048] Table 1

[0049]

[0050] After testing, it was found that no compatibilizer was added to nylon 6 and polyphenylene ether in comparative example 1, and the compatibility between the two was poor, resulting in poor strength and toughness of the plastic material, and low bending strength, impact strength, tensile strength and elongation at break.

[0051] Examples 1-5 incorporate polyphenylamide, which contains 2,6-dimethylphenylene ether structural units similar to polyphenylene ether. and amide bond structural units similar to nylon 6 This allows polyphenylamide to act as a compatibilizer, enhancing the interfacial interaction between nylon 6 and polyphenylene ether and improving their compatibility, thereby obtaining a PA / PPE alloy composite plastic material with better mechanical properties, exhibiting higher flexural strength, impact strength, tensile strength and elongation at break.

[0052] In Comparative Example 2, 1,4-phenylenediamine and succinyl chloride were used for polymerization reaction. The resulting polyphenylamide did not contain 2,6-dimethylphenylene ether structural units, and could not improve the compatibility between nylon 6 and polyphenylene ether, and could not act as a compatibilizer, resulting in poor strength and toughness of the plastic material.

[0053] Comparative Examples 3 and 4 use conventional maleic anhydride grafted POE and maleic anhydride grafted SEBS as compatibilizers, which improve the mechanical properties of the plastic material. The mechanical properties such as bending strength and impact strength are higher than those of Comparative Example 1, but significantly lower than those of the embodiments, indicating poor compatibilization effect.

[0054] While some embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for preparing a high-strength PA alloy plastic material, characterized in that: The preparation method of the high-strength PA alloy plastic material comprises the following steps: Step (1), placing a reaction vessel in an ice-water bath, adding N,N-dimethylformamide, 2,6-dimethylphenylenedi(oxyethylamine), and triethylamine, stirring, and dropwise adding a diacyl chloride compound, pouring the solution into ethanol for precipitation after the reaction, filtering, washing with water and ethanol in sequence, and drying to obtain polyphenylene ether amide; Step (2): mixing nylon 6, polyphenylene ether, polyphenylene ether amide, antioxidant and additives, placing the mixture in a twin-screw extruder, and melt-extruding and granulating the mixture to obtain a high-strength PA alloy plastic material.

2. The method for preparing high-strength PA alloy plastic material according to claim 1, characterized in that: In the step (1), the molar ratio of 2,6-dimethylphenylenedi(oxyethylamine), triethylamine, and diacyl chloride is 1:(2.2-2.6):(0.9-1.1).

3. The method for preparing high-strength PA alloy plastic material according to claim 1, characterized in that: The diacyl chloride compound is succinyl chloride, glutaryl chloride or adipoyl chloride.

4. The method for preparing a high-strength PA alloy plastic material according to claim 1, characterized in that: The reaction in step (1) is carried out at 40-60° C. for 12-18 hours.

5. The method for preparing high-strength PA alloy plastic material according to claim 1, characterized in that: The mass ratio of nylon 6, polyphenylene ether, and polyphenylene ether amide in step (2) is (30-50):(50-70):(1.5-5).

6. The method for preparing high-strength PA alloy plastic material according to claim 1, characterized in that: In the step (2), the antioxidant is antioxidant 1010, antioxidant 168 or antioxidant 1098; and the auxiliary agent is calcium stearate or zinc stearate.

7. The method for preparing high-strength PA alloy plastic material according to claim 1, characterized in that: In step (2), the temperature of each section of the extruder barrel is 245-265°C, and the head temperature is 260°C.

8. The method for preparing high-strength PA alloy plastic material according to claim 2, characterized in that: The preparation method of the 2,6-dimethylphenylenedi(oxyethylamine) is as follows: (1) Add N,N-dimethylformamide, 2,6-dimethylhydroquinone, 2-(Boc-amino) bromoethane, and potassium carbonate to a reaction vessel, heat to 80-90°C, stir and react for 18-24 hours, add water, and then extract with dichloromethane. The dichloromethane organic phase is dried over anhydrous sodium sulfate, filtered, and the filtrate is rotary evaporated, washed, and dried to obtain an intermediate; (2) Add dichloromethane, trifluoroacetic acid and the intermediate into the reaction vessel, react at room temperature for 2-3 hours, rotary evaporate, wash and dry to obtain 2,6-dimethylphenylenedi(oxyethylamine).

9. The method for preparing a high-strength PA alloy plastic material according to claim 8, characterized in that: The molar ratio of the 2,6-dimethylhydroquinone, 2-(Boc-amino)ethyl bromide and potassium carbonate is 1:(2.6-3.2):(5-6).

10. The method for preparing high-strength PA alloy plastic material according to claim 8, characterized in that: The molar ratio of the trifluoroacetic acid and the intermediate is (16-20):1.

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