A method for recycling mica board scraps and a method for preparing polymer materials

Abstract

The invention discloses a method for recycling mica plate scraps and a method for preparing a polymer material, comprising the following steps: S1, coarse crushing; S2, high-temperature treatment; S3, fine crushing; S4, surface modification; the mica plate scraps of the invention are surface-modified by a complexing agent, a titanate coupling agent and a silane coupling agent; the complexing agent can form a complex with metal ions to reduce the influence of impurity ions on the surface of mica flakes; the titanate coupling agent and the silane coupling agent are adsorbed on the surface of the mica flakes to improve the quality of the mica scraps; compared with the existing mica plate scrap recycling method, the polymer material prepared from the filler obtained by the recycling method of the invention has excellent mechanical properties, high-temperature resistance and ultraviolet aging resistance, and can be used in a large amount in harsh environments to replace ordinary polymer materials.

Description

Technical Field

[0001] The invention relates to the field of mica boards, and in particular to a method for recycling mica board scraps and a method for preparing a polymer material. Background Art

[0002] Mica has very high insulation and thermal insulation properties, good chemical stability, and resistance to strong acids, strong alkalis and pressure, so it is an important raw material for manufacturing electrical equipment; the most widely used in the industrial field is muscovite, followed by phlogopite, mostly used in the building materials industry, welding rods, plastics, electrical insulation, papermaking, asphalt paper, rubber and pearlescent pigments and other chemical industries.

[0003] Due to the difficulty of mining, mica stripping is entirely manual, resulting in extremely low yields. An effective way to address this problem is to increase the utilization of mica itself, and one important approach is papermaking. Mica sheets are a key application area for mica paper, widely used in electric heating appliances as gaskets, supporting insulation, and thermal insulation for new energy batteries. The emergence of mica sheets has greatly promoted the development of the electric heating appliance industry. However, mica sheets are cut or punched into various shapes during use. This process generates a significant amount of scrap, typically around 2-5%. Improper handling of these scraps not only results in a significant waste of resources, but also poses a serious environmental risk as solid waste.

[0004] Patent publication number CN109277396B provides a recycling process for mica board scraps, in which a disintegrating agent is added to the mica board scraps, and the adhesive effect of the mica board scraps is reduced after chemical soaking; Patent publication number CN111395032A provides a method for preparing mica paper pulp, which uses scraps and waste materials as raw materials to prepare mica paper with high insulation strength and dielectric strength; However, mica powder is a hydrophilic mineral with high polarity, and has a large difference in interfacial properties with high polymers, resulting in poor compatibility. The mica paper scraps in the patent CN100507145C are processed by chemical soaking to separate the adhesive from the mica, and then mechanically opened and pulped to make paper again. The mica paper treated by this method has a weakened van der Waals force between the mica sheets, which affects the mechanical strength and performance of the mica paper. Summary of the Invention

[0005] In view of the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method for recycling mica board scraps and a method for preparing polymer materials, so as to solve the problems of low mechanical strength, poor compatibility and poor product performance of mica boards in the existing processing technology.

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

[0007] In one aspect, the present invention provides a method for recycling mica board scraps, comprising the following steps:

[0008] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 80-100 mesh;

[0009] S2, high temperature treatment, heating the powder obtained in step S1 at 500-850°C for 0.5-1.5h;

[0010] S3, crushing the powder obtained in step S2 into 325-2000 mesh crushed materials;

[0011] S4, surface modification, modifying the crushed material obtained in step S3 with a complexing agent, a titanate coupling agent and a silane coupling agent to obtain filler A.

[0012] Further preferably, the specific process of step S4 includes the following steps:

[0013] Weigh the crushed material from step S3, add ethanol solution at a molar ratio of crushed material to ethanol solution = 1:(15-20), then add the complexing agent, titanate coupling agent and silane coupling agent at 80-90°C, mix well, stir for 0.5-1h, and then cool to 20-25°C.

[0014] Further preferably, the complexing agent in step S4 includes EDTA or oxalic acid.

[0015] Further preferably, the titanate coupling agent in step S4 includes one of JN114, JN-9, YB-203 or YB-201.

[0016] Further preferably, the silane coupling agent in step S4 includes at least one of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, propyltriethoxysilane, mercaptopropyltriethoxysilane, ethylenediaminepropyltriethoxysilane, ethylenediaminepropylmethyldimethoxysilane, vinyltriacetoxysilane or vinyltriethoxysilane.

[0017] Further preferably, in step S4, the molar ratio of the crushed material, the complexing agent, the titanate coupling agent and the silane coupling agent is 1:0.05-0.1:0.1-0.2:0.18.

[0018] On the other hand, the present invention also provides a method for preparing a polymer material, wherein the polymer material is prepared using filler A obtained by the mica board scrap recycling method described in the first aspect.

[0019] Further preferably, the specific preparation process includes the following steps: blending the filler A, the compatibilizer, and the polymer material particles, extruding, and pelletizing to obtain the modified polymer material particles.

[0020] More preferably, the specific preparation method further includes the following steps:

[0021] A1, weigh 0.5-25 parts of filler A, 1.5-15 parts of compatibilizer and 100 parts of polymer material particles;

[0022] A2, first stir and mix the polymer material particles and the compatibilizer, then add the filler A, extrude, and adjust the feeding speed so that the distribution ratio of each component meets the specified value;

[0023] A3, granulation, adjust the temperature and pressure parameter values.

[0024] Further preferably, the polymer material includes at least one of polyethylene or polypropylene.

[0025] Further preferably, the compatibilizer includes at least one of PE-g-MAH, PP-g-MAH, PE-g-ST or PP-g-ST.

[0026] Further preferably, the mixing, extrusion and granulation are mainly completed by a twin-screw extruder. During granulation, the temperature of the feeding section is set to 145-185°C, the temperature of the conveying section is set to 205-210°C, the temperature of the kneading section is set to 210-220°C, and the vacuum pressure of the vacuum system is -0.06±0.01MPa.

[0027] The method for recycling mica board scraps and the method for preparing polymer materials of the present invention have the following beneficial effects compared with the prior art:

[0028] (1) In the existing recycling process of mica board scraps, the mechanical strength of the mica board decreases after chemical soaking. EDTA or oxalic acid can form complexes with metal ions, reducing the impact of impurity ions on the surface of mica flakes and improving the quality of mica scraps. At the same time, titanate coupling agents and silane coupling agents can effectively adsorb on the mica surface, improving the compatibility of mica in polymer materials such as polypropylene or polyethylene, thereby improving the strength of the polymer materials.

[0029] (2) When existing mica sheets are compounded with polymers, they have poor compatibility, are prone to agglomeration, and have poor dispersion. However, PE-g-MAH, PP-g-MAH, PE-g-ST, or PP-g-ST can promote the interfacial adhesion between mica sheets and polypropylene or polyethylene, thereby improving the compatibility between mica sheets and polypropylene / polyethylene polymer materials.

[0030] (3) The polymer material prepared by modifying the mica board scraps of the present invention has the advantages of high impact strength, low smoke, halogen-free and flame retardancy, and also has excellent UV resistance. DETAILED DESCRIPTION

[0031] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Example 1

[0033] A method for recycling mica board scraps, the specific preparation process includes the following steps:

[0034] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 80 mesh;

[0035] S2, high temperature treatment, heating the powder obtained in step S1 at 500°C for 1.5h;

[0036] S3, crushing the powder obtained in step S2 into 325 mesh pieces;

[0037] S4, surface modification, weigh the crushed material from step S3, first add ethanol solution at a molar ratio of crushed material: ethanol solution = 1:15, then add EDTA, JN114 and γ-aminopropyltriethoxysilane at a molar ratio of crushed material, complexing agent, titanate coupling agent and silane coupling agent = 1:0.05:0.1:0.18 at 80°C, mix well, stir for 1 hour, and then cool to 20°C.

[0038] A method for preparing a polymer material comprises the following steps:

[0039] A1, weigh 0.5 parts of filler A, 1.5 parts of compatibilizer PP-g-MAH and 100 parts of polymer material PPZ30S particles;

[0040] A2: First, mix the polymer material particles and the compatibilizer evenly, then add filler A. The compatibilizer PP-g-MAH and polymer material PPZ30S particles are fed into the twin-screw extruder through the main feed port of the feeder via a loss-in-weight feeder. Filler A is fed into the twin-screw extruder through the side feed port via a loss-in-weight feeder via an auxiliary feeding system. The feeding speed is adjusted so that the distribution ratio of each group meets the specified value.

[0041] A3. Start the twin-screw extruder for granulation. During granulation, the temperature of the feeding section is set to 145°C, the temperature of the conveying section is set to 205°C, the temperature of the kneading section is set to 210°C, and the vacuum pressure of the vacuum system is -0.07 MPa; thus, the modified polymer material particle sample is obtained.

[0042] Example 2

[0043] A method for recycling mica board scraps, the specific preparation process includes the following steps:

[0044] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 100 mesh;

[0045] S2, high temperature treatment, heating the powder obtained in step S1 at 850°C for 0.5h;

[0046] S3, crushing the powder obtained in step S2 into 2000 mesh crushed materials;

[0047] S4, surface modification, weigh the crushed material from step S3, first add ethanol solution at a molar ratio of crushed material: ethanol solution = 1:20, then add EDTA, JN-9 and γ-glycidyloxypropyltrimethoxysilane at a molar ratio of crushed material, complexing agent, titanate coupling agent and silane coupling agent = 1:0.1:0.2:0.18 at 90°C, mix well, stir for 0.5h, and then cool to 25°C.

[0048] A method for preparing a polymer material comprises the following steps:

[0049] A1, by weight, weigh 25 parts of filler A, 15 parts of compatibilizer PP-g-MAH, and 100 parts of polymer material PP Z30S particles;

[0050] A2, first stir and mix the polymer material particles and the compatibilizer, then add the filler A, wherein the compatibilizer PP-g-MAH and the polymer material PPZ30S particles are fed into the twin-screw extruder through the main feed port of the feeder via a loss-in-weight feeding scale, and the filler A is fed into the twin-screw extruder through the side feed port via a loss-in-weight feeding scale through an auxiliary feeding system. Extrusion is carried out, and the feeding speed is adjusted so that the distribution ratio of each group meets the specified value;

[0051] A3, granulation, start the twin-screw extruder for granulation. During granulation, the temperature of the feeding section is set to 185°C, the temperature of the conveying section is set to 210°C, the temperature of the kneading section is set to 220°C, and the vacuum pressure of the vacuum system is -0.05 MPa; thus, the modified polymer material particle sample is obtained.

[0052] Example 3

[0053] A method for recycling mica board scraps, the specific preparation process includes the following steps:

[0054] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 90 mesh;

[0055] S2, high temperature treatment, heating the powder obtained in step S1 at 750°C for 45 minutes;

[0056] S3, crushing the powder obtained in step S2 into 1500 mesh crushed materials;

[0057] S4, surface modification, weigh the crushed material from step S3, first add ethanol solution at a molar ratio of crushed material: ethanol solution = 1:17, then add oxalic acid, YB-203 and γ-methacryloxypropyltrimethoxysilane at a molar ratio of crushed material, complexing agent, titanate coupling agent and silane coupling agent = 1:0.06:0.15:0.18 at 85°C, mix well, stir for 45 minutes, and then cool to 22°C.

[0058] A method for preparing a polymer material comprises the following steps:

[0059] A1, by weight, weigh 15 parts of filler A, 10 parts of compatibilizer PE-g-MAH, and 100 parts of polymer material PP Z30S particles;

[0060] A2, first stir and mix the polymer material particles and the compatibilizer, then add the filler A, wherein the compatibilizer PE-g-MAH and the polymer material PPZ30S particles are fed into the twin-screw extruder through the main feeding port of the feeder via a loss-in-weight feeding scale, and the filler A is fed into the twin-screw extruder through the side feeding port via a loss-in-weight feeding scale through an auxiliary feeding system. Extrusion is carried out, and the feeding speed is adjusted so that the distribution ratio of each group meets the specified value for extrusion;

[0061] A3, granulation, start the twin-screw extruder for granulation. During granulation, the temperature of the feeding section is set to 160°C, the temperature of the conveying section is set to 208°C, the temperature of the kneading section is set to 215°C, and the vacuum pressure of the vacuum system is -0.06 MPa; thus, the modified polymer material particle sample is obtained.

[0062] Example 4

[0063] A method for recycling mica board scraps, the specific preparation process includes the following steps:

[0064] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 90 mesh;

[0065] S2, high temperature treatment, heating the powder obtained in step S1 at 750°C for 45 minutes;

[0066] S3, crushing the powder obtained in step S2 into 1500 mesh crushed materials;

[0067] S4, surface modification, weigh the crushed material from step S3, first add ethanol solution according to the molar ratio of crushed material: ethanol solution = 1:17, then add oxalic acid, YB-201, propyltriethoxysilane and mercaptopropyltriethoxysilane at a molar ratio of crushed material, complexing agent, titanate coupling agent and silane coupling agent = 1:0.05:0.1:0.18 at 85°C, wherein the molar ratio of propyltriethoxysilane to mercaptopropyltriethoxysilane is 1:1, mix well, stir for 45 minutes, and then cool to 25°C.

[0068] A method for preparing a polymer material comprises the following steps:

[0069] A1, by weight, weigh 8 parts of filler A, 10 parts of compatibilizer PE-g-MAH, and 100 parts of polymer material PP Z30S particles;

[0070] A2, first stir and mix the polymer material particles and the compatibilizer, then add the filler A, wherein the compatibilizer PE-g-MAH and the polymer material PPZ30S particles are fed into the twin-screw extruder through the main feeding port of the feeder via a loss-in-weight feeding scale, and the filler A is fed into the twin-screw extruder through the side feeding port via a loss-in-weight feeding scale through an auxiliary feeding system. Extrusion is carried out, and the feeding speed is adjusted so that the distribution ratio of each group meets the specified value for extrusion;

[0071] A3, granulation, start the twin-screw extruder for granulation. During granulation, the temperature of the feeding section is set to 160°C, the temperature of the conveying section is set to 208°C, the temperature of the kneading section is set to 215°C, and the vacuum pressure of the vacuum system is -0.06 MPa; thus, the modified polymer material particle sample is obtained.

[0072] Example 5

[0073] A method for recycling mica board scraps, the specific preparation process includes the following steps:

[0074] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 90 mesh;

[0075] S2, high temperature treatment, heating the powder obtained in step S1 at 750°C for 45 minutes;

[0076] S3, crushing the powder obtained in step S2 into 1500 mesh crushed materials;

[0077] S4, surface modification, weigh the crushed material from step S3, first add ethanol solution according to the molar ratio of crushed material: ethanol solution = 1:17, then add EDTA, JN114, ethylenediaminepropyltriethoxysilane and ethylenediaminepropylmethyldimethoxysilane at a molar ratio of crushed material, complexing agent, titanate coupling agent and silane coupling agent = 1:0.08:0.15:0.18 at 85°C, wherein the molar ratio of ethylenediaminepropyltriethoxysilane to ethylenediaminepropylmethyldimethoxysilane is 1:1, mix well, stir for 45 minutes, and then cool to 25°C.

[0078] A method for preparing a polymer material comprises the following steps:

[0079] A1, by weight, weigh 12 parts of filler A, 10 parts of compatibilizer PE-g-ST, and 100 parts of polymer material polyethylene particles;

[0080] A2: First, the polymer material particles and the compatibilizer are stirred and mixed uniformly, and then filler A is added. The compatibilizer PE-g-ST and the polymer material polyethylene particles are fed into the twin-screw extruder through the main feeding port of the feeder via a loss-in-weight feeding scale. The filler A is fed into the twin-screw extruder through the side feeding port via a loss-in-weight feeding scale via an auxiliary feeding system. Extrusion is performed, and the feeding speed is adjusted so that the distribution ratio of each group meets the specified value.

[0081] A3, granulation, start the twin-screw extruder for granulation. During granulation, the temperature of the feeding section is set to 160°C, the temperature of the conveying section is set to 208°C, the temperature of the kneading section is set to 215°C, and the vacuum pressure of the vacuum system is -0.06 MPa; thus, the modified polymer material particle sample is obtained.

[0082] Example 6

[0083] A method for recycling mica board scraps, the specific preparation process includes the following steps:

[0084] S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 90 mesh;

[0085] S2, high temperature treatment, heating the powder obtained in step S1 at 750°C for 45 minutes;

[0086] S3, crushing the powder obtained in step S2 into 1500 mesh crushed materials;

[0087] S4, surface modification, weigh the crushed material from step S3, first add ethanol solution according to the molar ratio of crushed material: ethanol solution = 1:17, then add EDTA, JN114, vinyl triacetoxysilane and vinyl triethoxysilane at a molar ratio of crushed material, complexing agent, titanate coupling agent and silane coupling agent = 1:0.05-0.1:0.1-0.2:0.18 at 85°C, wherein the molar ratio of vinyl triacetoxysilane to vinyl triethoxysilane is 1:1, mix well, stir for 45 minutes, and then cool to 25°C.

[0088] A method for preparing a polymer material comprises the following steps:

[0089] A1, by weight, weigh 8 parts of filler A, 10 parts of compatibilizer PE-g-ST, and 100 parts of polymer material polyethylene particles;

[0090] A2: First, the polymer material particles and the compatibilizer are stirred and mixed uniformly, and then filler A is added. The compatibilizer PE-g-ST and the polymer material polyethylene particles are fed into the twin-screw extruder through the main feeding port of the feeder via a loss-in-weight feeding scale. The filler A is fed into the twin-screw extruder through the side feeding port via a loss-in-weight feeding scale via an auxiliary feeding system. Extrusion is performed, and the feeding speed is adjusted so that the distribution ratio of each group meets the specified value.

[0091] A3, granulation, start the twin-screw extruder for granulation. During granulation, the temperature of the feeding section is set to 160°C, the temperature of the conveying section is set to 208°C, the temperature of the kneading section is set to 215°C, and the vacuum pressure of the vacuum system is -0.06 MPa; thus, the modified polymer material particle sample is obtained.

[0092] Comparative Example 1

[0093] A method for recycling mica board scraps and a method for preparing polymer materials are provided, which differ from Example 1 in that no complexing agent and titanate coupling agent are added to the scraps in step S4.

[0094] Comparative Example 2

[0095] A method for recycling mica board scraps and a method for preparing polymer materials are provided, which differ from Example 2 in that no compatibilizer is added in step A1.

[0096] Comparative Example 3

[0097] A method for recycling mica board scraps and a method for preparing polymer materials are provided, which differ from Example 3 in that step S4 uses polyester to modify the surface of the mica scraps.

[0098] Comparative Example 4

[0099] A method for recycling mica board scraps and a method for preparing polymer materials are provided, which differ from Example 4 in that the filler is prepared using the method disclosed in Publication No. CN100507145C.

[0100] Comparative Example 5

[0101] A method for recycling mica board scraps and a method for preparing polymer materials are different from Example 5 in that the preparation process does not include step S4.

[0102] Comparative Example 6

[0103] A method for recycling mica board scraps and a method for preparing polymer materials, which differ from Example 6 in that the compatibilizer is 1 part of PP-g-ST.

[0104] Performance Testing

[0105] The materials were primarily tested for impact resistance, flame retardancy, and UV aging resistance. Impact resistance was tested according to GB / T 1043.1-2008, vertical combustion was tested according to GB / T 2408-2008, and UV resistance was tested using a dual-lamp enclosed carbon arc 720° pilot test.

[0106] Table 1 Performance test of polymer materials obtained in Examples 1-6 and Comparative Examples 1-6

[0107]

[0108] It can be seen from the above that, compared with Comparative Example 1, in Example 1 of the present invention, after the complexing agent and the titanate coupling agent are introduced, the complexing agent can form a complex with the metal ions, and the titanate coupling agent can work together with the silane coupling agent to reduce the influence of impurity ions on the surface of mica flakes and improve the mechanical tensile strength; compared with Comparative Example 2, in Example 2, no compatibilizer is added, and there is a large difference in the interfacial properties with the polymer, and the performance of the prepared polymer materials is reduced; compared with Comparative Example 5, in Example 5, the mica board scraps are surface-modified after being opened and have good high impact strength, flame retardancy and UV resistance.

[0109] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for recycling mica board scraps, characterized in that: The steps include: S1, coarse crushing, crushing the waste mica board scraps into powder with a particle size of 80-100 mesh; S2, high temperature treatment, heating the powder obtained in step S1 at 500-850°C for 0.5-1.5h; S3, crushing the powder obtained in step S2 into 325-2000 mesh crushed materials; S4, surface modification, modifying the crushed material obtained in step S3 with a complexing agent, a titanate coupling agent, and a silane coupling agent to obtain filler A; The specific process of step S4 includes the following steps: Weigh the crushed material from step S3, add ethanol at a molar ratio of crushed material to ethanol = 1:(15-20), then add the complexing agent, titanate coupling agent, and silane coupling agent at 80-90°C, mix well, stir for 0.5-1h, and then cool to 20-25°C; The molar ratio of the crushed material, the complexing agent, the titanate coupling agent and the silane coupling agent in step S4 is 1:0.05-0.1:0.1-0.2:0.

18.

2. The method for recycling mica board scraps according to claim 1, wherein: The complexing agent in step S4 includes EDTA or oxalic acid.

3. The method for recycling mica board scraps according to claim 2, wherein: The titanate coupling agent in step S4 includes one of JN114, JN-9, YB-203 or YB-201.

4. A method for preparing a polymer material, characterized in that: The filler A is prepared by using the mica board scrap recycling method described in any one of claims 1 to 3.

5. The method for preparing a polymer material according to claim 4, wherein: The steps include: The filler A, the compatibilizer and the polymer material particles are melt-blended, extruded and pelletized to obtain the modified polymer material particles.

6. The method for preparing a polymer material according to claim 5, wherein: The specific preparation method also includes the following steps: A1, weigh 0.5-25 parts of filler A, 1.5-15 parts of compatibilizer and 100 parts of polymer material particles; A2, first stir and mix the polymer material particles and the compatibilizer evenly, then add the filler A, extrude, and adjust the feeding speed so that the distribution ratio of each component meets the specified value; A3, granulation, adjust the temperature and pressure parameter values.

7. The method for preparing a polymer material according to claim 5, wherein: The polymer material particles include polyethylene or polypropylene.

8. The method for preparing a polymer material according to claim 5, wherein: The compatibilizer includes at least one of PE-g-MAH, PP-g-MAH, PE-g-ST or PP-g-ST.

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