A method for recycling a polyaryletherketone composite

Abstract

The application discloses a recycling method of an amorphous polyaryletherketone high polymer material, realizes a recycling method of expensive polyaryletherketone resin, and has a series of advantages such as simplicity, high efficiency, low cost and recyclability. The recycling technology has the advantages of wide adaptability, low cost, simplicity, high efficiency and recyclability, and can be used for preparation of various soluble high-temperature-resistant resins such as amorphous polyaryletherketone and composite materials thereof.

Description

TECHNICAL FIELD

[0001] The application relates to a recycling method of a polyaryletherketone composite material and belongs to the technical field of polymers and recycling. BACKGROUND

[0002] Polyaryletherketone (PAEK) is a full-aromatic thermoplastic special engineering plastic, which has been regarded as a key material for national defense and military industry since it was developed and is widely used in the fields of aerospace, automobile industry, electronics and electrical appliances, and medical machinery. Phenolphthalein-based polyaryletherketone (PEK-C) is a typical amorphous polymer in PAEK, which has the advantages of high heat resistance, high strength, high modulus, good dimensional stability, insulation, corrosion resistance, radiation resistance, self-flame retardancy, outstanding anti-fatigue performance, and outstanding tribological performance. However, the melt viscosity of PEK-C is high, and even at high temperature, the flowability of the melt is still poor; meanwhile, the low friction coefficient leads to easy slipping when using a screw extruder. This makes it difficult to use conventional melt processing methods such as extrusion and injection molding to form PEK-C.

[0003] Compared with melt processing, powder sintering is a low-temperature processing technology, which has the following advantages in adjusting the structure and performance of the product: (1) reducing component segregation and organizational segregation, eliminating coarse and uneven organizational structure; (2) preparing a series of high-performance non-equilibrium materials such as amorphous, microcrystalline, quasi-crystalline, and supersaturated solid solution; (3) producing products with special structures and properties that cannot be produced by ordinary melting, such as new porous biomaterials and porous separation membrane materials. Low-temperature processing brings many benefits, one of which is to ensure the secondary dissolution of the polymer. Although the original material has excellent solubility, high-temperature processing causes micro-crosslinking, which leads to a decrease in solubility, and in severe cases, even secondary dissolution is difficult, which brings great challenges to the recycling economy of the material. SUMMARY

[0004] The purpose of the present application is to provide a simple and efficient recycling method for amorphous polyaryletherketone.

[0005] In the present application, amorphous polyaryletherketone powder is used as raw material, and a uniform temperature field is constructed on the surface of the green body during sintering, which reduces the temperature difference between the surface and the interior of the material during the heating and cooling process, thereby preparing a smooth and defect-free sintered product.

[0006] According to one aspect of the present application, a recycling method of a polyaryletherketone composite material is provided, which at least comprises the following steps:

[0007] The polyaryletherketone composite material is mixed with a solvent, and after filtration, drying and purification, polyaryletherketone is obtained.

[0008] The solvent is selected from at least one of chloroform, dichloromethane, 1,2-dichloroethane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, benzophenone or acetophenone;

[0009] The mass of the solvent is 5-20 times of the mass of the polyaryletherketone composite material.

[0010] The temperature of the mixing is 200 DEG C.

[0011] The recovery rate of the polyaryletherketone is greater than or equal to 90%.

[0012] The preparation method of the polyaryletherketone composite material at least comprises the following steps:

[0013] The raw materials containing the polymeric material and the heat-conducting material are mixed, warm-pressing forming is carried out to obtain a parison, the heat-conducting medium is covered on the surface of the parison, and sintering forming is carried out to obtain the composite material.

[0014] The polymeric material is selected from amorphous phenolphthalein-based polyaryletherketone and / or polyether ether ketone;

[0015] The heat-conducting material is selected from at least one of boron nitride, graphite or carbon fiber;

[0016] The heat-conducting medium is selected from polyaryletherketone powder or quartz sand powder;

[0017] The mass ratio of the use amount of each substance is that the polymeric material is 100 parts, and the heat-conducting filler is 5-40 parts.

[0018] The heat-conducting medium completely wraps the parison.

[0019] The temperature of the warm-pressing forming is 20-100 DEG C.

[0020] The pressure of the warm-pressing forming is 20-80 MPa.

[0021] The time of the warm-pressing forming is 0-10 h.

[0022] The temperature of the sintering forming is 250-320 DEG C.

[0023] The time of the sintering forming is 1-10 h.

[0024] The sintered sample of the polyaryletherketone powder prepared by the method does not crosslink and still has good solubility.

[0025] The material is prepared by the following steps.

[0026] The beneficial effects that can be produced by the application include:

[0027] 1. A simple, effective, and low-cost method for recycling polyaryletherketones is provided.

[0028] 2. The provided polymer composite material has high flatness, no warping, excellent mechanical properties, tensile strength of 150MPa, tensile modulus of 6GPa, can be recycled, has high yield, and saves costs. Detailed Implementation

[0029] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0030] All examples involved the preparation of polyaryletherketone composite materials followed by recycling.

[0031] Example 1

[0032] Polyaryletherketone (PAGE) sintered products were prepared by mechanically blending 100 parts of amorphous PAGE into powder using a ball mill at 600 rpm. The powder was then warm-pressed using a flat vulcanizing machine at 100°C, 80 MPa, and 10 min. Finally, a layer of amorphous PAGE powder was coated onto the surface of the preform, which was then transferred to a sintering furnace for sintering at 250°C for 6 h.

[0033] The polyaryletherketone powder sintered material was dissolved in 500 parts of tetrahydrofuran solvent at 45°C. After filtration, precipitation, drying, and purification, the recovery rate was 98.5%. The structure of the amorphous polyaryletherketone is as follows:

[0034]

[0035] Example 2

[0036] Polyaryletherketone (PAGE) sintered products were prepared by mechanically blending 100 parts of amorphous PAGE and 20 parts of crystalline PAGE in a ball mill at 600 rpm. The powder was then warm-pressed using a flat vulcanizing machine at 100°C, 80 MPa, and 10 min. Finally, a layer of amorphous PAGE powder was coated onto the surface of the preform, which was then transferred to a sintering furnace for sintering at 250°C for 6 h.

[0037] Polyaryletherketone (PGE) powder sintering material was dissolved in 900 parts of N,N-dimethylformamide solvent at 80℃. After filtration, precipitation, drying, and purification, the recovery rate of amorphous PGE was 77.5%. The filter residue was repeatedly washed and dried, and the recovery rate of crystalline PGE was 15.6%, with a total recovery rate of 93.1%. The structure of the amorphous PGE is as follows:

[0038]

[0039] Example 3

[0040] Polyaryletherketone (PGE) sintered products were prepared by mechanically blending 100 parts of amorphous PGE and 20 parts of crystalline PGE using a ball mill at 600 rpm. The powder was then warm-pressed using a flat vulcanizing machine at 100°C, 80 MPa, and 10 min. Finally, a layer of quartz sand powder was applied to the surface of the preform, which was then transferred to a sintering furnace for sintering at 320°C for 6 h.

[0041] Polyaryletherketone (PGE) powder sintering material was dissolved at 140°C in 600 parts of N,N-dimethylacetamide and 1000 parts of N-methylpyrrolidone solvent. After filtration, precipitation, drying, and purification, the amorphous PGE recovered 75.5%. The filter residue, after repeated washing and drying, showed a 15.8% recovery rate of crystalline PGE, resulting in a total recovery rate of 93.3%. The structure of the amorphous PGE is as follows:

[0042]

[0043] Example 4

[0044] Polyaryletherketone (PGE) composite sintered products were prepared by mechanically blending 100 parts of amorphous PGE and 20 parts of carbon fiber using a ball mill at 600 rpm. The powder was then warm-pressed using a flat vulcanizing machine at 100°C, 80 MPa, and 10 min. Finally, a layer of quartz sand powder was applied to the surface of the preform, which was then transferred to a sintering furnace for sintering at 280°C for 6 h.

[0045] The polyaryletherketone powder sintered material was dissolved in 900 parts of benzyl alcohol solvent at 100℃. After filtration, precipitation, drying, and purification processes, the recovery rate of amorphous polyaryletherketone was 94.6%. The structure of the amorphous polyaryletherketone is as follows:

[0046]

[0047] Example 5

[0048] Polyaryletherketone (PGE) composite sintered products were prepared by mechanically blending 100 parts of amorphous PGE and 20 parts of graphite using a ball mill at 600 rpm. The powder was then warm-pressed using a flat vulcanizing machine at 100°C, 80 MPa, and 10 min. Finally, a layer of quartz sand powder was applied to the surface of the preform, which was then transferred to a sintering furnace for sintering at 250°C for 6 h.

[0049] The polyaryletherketone composite sintered product was dissolved in 600 parts of dichloromethane and 1400 parts of chloroform solvent at 100°C. After filtration, decolorization, precipitation, drying, and purification, the recovery rate of amorphous polyaryletherketone was 90.2%. The structure of the amorphous polyaryletherketone is as follows:

[0050]

[0051] Example 6

[0052] A polyaryletherketone (PAE) composite sintered product was prepared by mechanically blending 100 parts of amorphous PAE and 20 parts of boron nitride in a ball mill at 600 rpm. The powder was then warm-pressed using a flat vulcanizing machine at 100°C, 80 MPa, and 10 min. Finally, a layer of quartz sand powder was applied to the surface of the preform, which was then transferred to a sintering furnace for sintering at 250°C for 6 h. The structure of the amorphous PAE is as follows:

[0053]

[0054] Comparative Example

[0055] Molded polyaryletherketone (PAEK) products were prepared by mechanically blending 100 parts of phenolphthalein-based PAEK and 20 parts of boron nitride in a ball mill at 600 rpm. The powder was then molded using a flat vulcanizing machine at 380°C, 80 MPa, and 40 min. After dissolving the sample in 1200 parts of DMF solvent and heating to 80°C, a large amount of insoluble matter remained. Analysis indicated that the high temperature caused micro-crosslinking of the polymer. The insoluble matter, after drying, weighed 98 parts and contained a significant amount of boron nitride. The insoluble matter was strong, difficult to pulverize, and unsuitable for powder sintering. The soluble matter was precipitated and dried, with a recovery rate of 18%. The structure of the amorphous PAEK is as follows:

[0056]

[0057] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for recycling polyaryletherketone composite materials, characterized in that, At least the following steps are included: The polyaryletherketone composite material was mixed with a solvent, filtered, dried and purified to obtain polyaryletherketone. The preparation method of the polyaryletherketone composite material includes at least the following steps: Raw materials containing polymer materials and thermally conductive materials are mixed, warm-pressed to obtain a preform, a thermally conductive medium is covered on the surface of the preform, and sintered to obtain the composite material. The polymer material is selected from amorphous phenolphthalein-based polyaryletherketone and / or polyetheretherketone; The thermally conductive material is selected from at least one of boron nitride, graphite, or carbon fiber; The thermally conductive medium is selected from polyaryletherketone powder or quartz sand powder; The mass ratio of each substance is: 100 parts of polymer material and 5-40 parts of thermally conductive filler. The thermally conductive medium completely encapsulates the preform; The temperature for warm pressing is 20–100°C; The pressure for the warm pressing process is 20–80 MPa; The warm pressing time is 0–10 hours; The sintering temperature is 250–320°C; The sintering time is 1 to 10 hours.

2. The recycling method according to claim 1, characterized in that, The solvent is selected from at least one of chloroform, dichloromethane, 1,2-dichloroethane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone or acetophenone; The mass of the solvent is 5 to 20 times the mass of the polyaryletherketone composite material.

3. The recycling method according to claim 1, characterized in that, The recovery rate of the polyaryletherketone is ≥90%.

4. The recycling method according to claim 1, characterized in that, The tensile strength of the polyaryletherketone composite material is higher than 90 MPa; the tensile modulus is higher than 2.2 GPa.

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