Biomass-inorganic nanoparticle composite carbon sphere, preparation method thereof, heat-resistant antistatic composite material and preparation method thereof

Abstract

The present invention belongs to the field of polymer materials, and in particular relates to a biomass-inorganic nanoparticle composite carbon sphere, a preparation method thereof, a heat-resistant antistatic composite material and a preparation method thereof. The biomass-inorganic nanoparticle composite carbon sphere provided by the present invention is prepared by hydrothermally reacting polybasic organic acid-etched nanoparticles, biomass powder and persulfate under microwave assistance, followed by washing, drying and oxygen-free calcination, and then ultrasonically reacting in a polybasic organic acid solution, followed by washing, drying and grinding. The biomass-inorganic nanoparticle composite carbon sphere provided by the present invention has good compatibility with polylactic acid, low raw material cost, simple preparation process, safety and environmental protection, and high yield; the heat-resistant antistatic composite material provided by the present invention uses polylactic acid as a base material, and is added with the biomass-inorganic nanoparticle composite carbon sphere provided by the present invention, and has very excellent heat resistance, electrical conductivity and mechanical properties.

Description

Technical Field

[0001] The present invention belongs to the field of polymer materials, and in particular relates to a biomass-inorganic nanoparticle composite carbon ball, a preparation method thereof, a heat-resistant antistatic composite material and a preparation method thereof. Background Art

[0002] As plastic bans continue to strengthen both domestically and internationally, biodegradable plastics have become a research hotspot within the polymer molding and processing industry. Polylactic acid (PLA), with its relatively low cost, wide availability of raw materials, and good biocompatibility, has shown great potential for application and has seen initial adoption in recent years.

[0003] In order to meet the needs of a wider range of applications, more and more polylactic acid composite materials have been developed. At present, the antistatic materials prepared by compounding with polylactic acid are mainly graphene, carbon nanotubes, etc. These carbon materials are not only expensive and complicated to prepare, but also have poor compatibility with polylactic acid. In contrast, biomass carbon balls have low price, excellent electrical conductivity and mechanical properties, but the traditional hydrothermal carbonization method has a cumbersome preparation process and extremely low yield, which restricts its promotion and large-scale production. At present, there is still a lack of an effective, high-yield, low-cost, simple and green carbon ball production technology.

[0004] In addition, polylactic acid has poor heat resistance, which limits its application scenarios. Although inorganic nanoparticles can effectively promote the crystallization process of polylactic acid and help improve the heat resistance of polylactic acid, inorganic nanoparticles have poor compatibility with polylactic acid. Excessive addition will lead to a decrease in the comprehensive mechanical properties of polylactic acid, especially in polymer materials with added carbon materials. This is particularly obvious. Therefore, there is still a lack of a preparation scheme for polylactic acid composite materials that can take into account antistatic properties, heat resistance and mechanical properties at the same time. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a biomass-inorganic nanoparticle composite carbon sphere, a preparation method thereof, a heat-resistant antistatic composite material and a preparation method thereof. The biomass-inorganic nanoparticle composite carbon sphere provided by the present invention has good compatibility with polylactic acid, low raw material cost, simple preparation process, safety and environmental protection, and high yield; the heat-resistant antistatic composite material provided by the present invention uses polylactic acid as a base material and is added with the biomass-inorganic nanoparticle composite carbon sphere provided by the present invention, and has very excellent heat resistance, electrical conductivity and mechanical properties.

[0006] The present invention provides a biomass-inorganic nanoparticle composite carbon sphere, which is prepared by hydrothermal reaction of polybasic organic acid corrosive nanoparticles, biomass powder and persulfate under microwave assistance, followed by washing, drying and oxygen-free calcination, and then ultrasonic reaction in polybasic organic acid solution, followed by washing, drying and grinding.

[0007] The polybasic organic acid corrosive nanoparticles are prepared by heating inorganic nanoparticles and polybasic organic acid in an organic solvent and then filtering.

[0008] The polybasic organic acid solution is the organic acid filtrate obtained after the filtration.

[0009] Preferably, the biomass powder is one or more of jute powder, peanut shell powder, fir bark powder, pine cone powder, bamboo shoot shell powder, coconut shell powder, nut shell powder, soybean pod powder, sunflower seed shell powder, sunflower stem powder, rice straw powder, rice husk powder, corn straw powder and sisal powder.

[0010] Preferably, the inorganic nanoparticles are one or more of titanium dioxide, silicon dioxide, talc, montmorillonite, kaolin, mica and hydroxyapatite.

[0011] Preferably, the polybasic organic acid is one or more of quinic acid, salicylic acid, malic acid, citric acid, tartaric acid and alginic acid.

[0012] Preferably, the persulfate is one or more of ammonium persulfate, potassium persulfate and sodium persulfate.

[0013] Preferably, based on 100 parts by weight of the biomass powder, the amount of the inorganic nanoparticles is 5 to 10 parts by weight, the amount of the polybasic organic acid is 20 to 30 parts by weight, and the amount of the persulfate is 200 to 400 parts by weight.

[0014] The present invention provides a method for preparing biomass-inorganic nanoparticle composite carbon spheres as described in the above technical solution, comprising the following steps:

[0015] a) heating the inorganic nanoparticles and the polybasic organic acid in an organic solvent to react, and filtering to obtain polybasic organic acid-etched nanoparticles and an organic acid filtrate, respectively;

[0016] b) subjecting the multi-organic acid corrosive nanoparticles, biomass powder and persulfate to a hydrothermal reaction under microwave assistance; after the reaction is completed, washing and drying the reaction product to obtain a dried material;

[0017] c) calcining the dried material in the absence of oxygen to obtain a pyrolysis material;

[0018] d) mixing the pyrolysis material with the organic acid filtrate and subjecting them to ultrasonic reaction; after the reaction is completed, washing, drying and grinding the reaction product to obtain biomass-inorganic nanoparticle composite carbon spheres.

[0019] Preferably, in step a), the temperature of the heating reaction is 50-70° C.; the time of the heating reaction is 1-3 hours;

[0020] In step b), the microwave power of the microwave-assisted method is 800-1200 W; the temperature of the hydrothermal reaction is 220-240° C.; and the time of the hydrothermal reaction is 12-24 hours.

[0021] In step c), the temperature of the oxygen-free calcination is 450-550° C. and the time of the oxygen-free calcination is 60-100 minutes;

[0022] In step d), the ultrasonic frequency of the ultrasonic reaction is 40 to 60 kHz; the temperature of the ultrasonic reaction is 60 to 80° C.; and the time of the ultrasonic reaction is 20 to 40 minutes.

[0023] The present invention provides a heat-resistant antistatic composite material, which is prepared by melt blending raw materials, wherein the raw materials include biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant and a chain extender;

[0024] The biomass-inorganic nanoparticle composite carbon spheres are the biomass-inorganic nanoparticle composite carbon spheres described in the above technical solution or the biomass-inorganic nanoparticle composite carbon spheres prepared by the preparation method described in the above technical solution.

[0025] The present invention provides a method for preparing the heat-resistant antistatic composite material described in the above technical solution, comprising the following steps:

[0026] Biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant and a chain extender are melt-blended to obtain a heat-resistant antistatic composite material.

[0027] Compared to the prior art, the present invention provides biomass-inorganic nanoparticle composite carbon spheres, a preparation method thereof, and a heat-resistant antistatic composite material and its preparation method. The biomass-inorganic nanoparticle composite carbon spheres provided by the present invention are prepared by hydrothermally reacting polybasic organic acid corrosive nanoparticles, biomass powder, and persulfate under microwave assistance, followed by washing, drying, and oxygen-free calcination. The polybasic organic acid corrosive nanoparticles are prepared by heating inorganic nanoparticles and polybasic organic acid in an organic solvent and filtering the resulting mixture. The polybasic organic acid solution is the organic acid filtrate obtained after filtration. The present invention utilizes persulfate to accelerate the biomass decomposition process, while simultaneously utilizing microwave-assisted deep heat transfer to promote the hydrothermal carbonization reaction and further increase the carbon sphere yield. Furthermore, the addition of inorganic nanoparticles promotes heterogeneous nucleation, accelerating the carbon sphere nucleation process, forming a core-shell structure and a cross-linked structure that encapsulate the nano-inorganic particles, thereby forming more composite carbon spheres. This reduces the amount of biomass carbon spheres used while achieving the same antistatic effect. The composite carbon spheres provided by the present invention have more stable structural characteristics and a more lasting antistatic effect; at the same time, the inorganic nanoparticles increase their compatibility with polylactic acid by virtue of the hydrophilic functional groups such as hydroxyl and carboxyl groups that accumulate on the surface of the carbon spheres during the hydrothermal carbon sphere formation process. No additional modification treatment is required when subsequently added to the polylactic acid, simplifying the process steps. The biomass-inorganic nanoparticle composite carbon spheres provided by the present invention have good compatibility with polylactic acid, low raw material cost, simple preparation process, safety and environmental protection, high yield, and good economic and environmental benefits. The heat-resistant antistatic composite material provided by the present invention is made by melt blending raw materials, the raw materials including biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant and a chain extender; the biomass-inorganic nanoparticle composite carbon spheres are the biomass-inorganic nanoparticle composite carbon spheres described in the above technical solution or the biomass-inorganic nanoparticle composite carbon spheres prepared by the preparation method described in the above technical solution. The heat-resistant antistatic composite material provided by the present invention uses polylactic acid as a base material and is supplemented with the biomass-inorganic nanoparticle composite carbon spheres of the present invention and an organic nucleating agent. The inorganic nanoparticles in the composite carbon spheres and the organic nucleating agent form a composite nucleating agent, which can effectively promote the crystallization process of polylactic acid and significantly improve the heat resistance and mechanical properties of the polylactic acid composite material. The polylactic acid composite material provided by the present invention has excellent heat resistance, electrical conductivity, and mechanical properties and has broad market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0029] Figure 1 This is a transmission electron micrograph of the biomass-inorganic nanoparticle composite carbon sphere provided in Example 2 of the present invention;

[0030] Figure 2 This is the diffraction ring pattern of the biomass-inorganic nanoparticle composite carbon sphere provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0031] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments 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 any creative efforts are within the scope of protection of the present invention.

[0032] The present invention provides a biomass-inorganic nanoparticle composite carbon sphere, which is prepared by hydrothermal reaction of polybasic organic acid corrosive nanoparticles, biomass powder and persulfate under microwave assistance, followed by washing, drying and oxygen-free calcination, and then ultrasonic reaction in polybasic organic acid solution, followed by washing, drying and grinding.

[0033] The polybasic organic acid corrosive nanoparticles are prepared by heating inorganic nanoparticles and polybasic organic acid in an organic solvent and then filtering.

[0034] The polybasic organic acid solution is the organic acid filtrate obtained after the filtration.

[0035] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the biomass powder is preferably one or more of jute powder, peanut shell powder, fir bark powder, pine cone powder, bamboo shoot shell powder, coconut shell powder, nut shell powder, soybean pod powder, sunflower seed shell powder, sunflower stem powder, rice straw powder, rice husk powder, corn straw powder and sisal powder. In one embodiment provided by the present invention, the biomass powder is pine cone powder and coconut shell powder, and the mass ratio of the pine cone powder to the coconut shell powder is preferably 1: (0.5-2), more preferably 1: 1; in one embodiment provided by the present invention, the biomass powder is nut shell powder and jute powder, and the mass ratio of the nut shell powder to the jute powder is preferably 1: (0.5-2), more preferably 1: 1; in one embodiment provided by the present invention, the biomass powder is sunflower stem powder, peanut shell powder and rice straw powder, and the mass ratio of the sunflower stem powder, peanut shell powder and rice straw powder is preferably 3: (1-5): (2-6), more preferably 3: 3: 4.

[0036] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the mesh number of the biomass powder is 400-600 mesh, specifically 400 mesh, 410 mesh, 420 mesh, 430 mesh, 440 mesh, 450 mesh, 460 mesh, 470 mesh, 480 mesh, 490 mesh, 500 mesh, 510 mesh, 520 mesh, 530 mesh, 540 mesh, 550 mesh, 560 mesh, 570 mesh, 580 mesh, 590 mesh or 600 mesh.

[0037] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the inorganic nanoparticles are preferably one or more of titanium dioxide, silicon dioxide, talc, montmorillonite, kaolin, mica, and hydroxyapatite. In one embodiment provided by the present invention, the inorganic nanoparticles are titanium dioxide and talc, and the mass ratio of titanium dioxide to talc is preferably 3:(2-6), more preferably 3:4; in one embodiment provided by the present invention, the inorganic nanoparticles are talc and montmorillonite, and the mass ratio of talc to montmorillonite is preferably 1:(0.5-2), more preferably 1:1; in one embodiment provided by the present invention, the inorganic nanoparticles are kaolin, titanium dioxide, and hydroxyapatite, and the mass ratio of kaolin, titanium dioxide, and hydroxyapatite is preferably 3:(1-5):(2-6), more preferably 3:3:4.

[0038] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the particle size of the inorganic nanoparticles is preferably 50 to 100 nm, specifically 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 95 nm or 100 nm.

[0039] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, based on 100 parts by weight of biomass powder, the amount of the inorganic nanoparticles is preferably 5 to 10 parts by weight, specifically 5 parts by weight, 5.5 parts by weight, 6 parts by weight, 6.5 parts by weight, 7 parts by weight, 7.5 parts by weight, 8 parts by weight, 8.5 parts by weight, 9 parts by weight, 9.5 parts by weight or 10 parts by weight.

[0040] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the polybasic organic acid is preferably one or more of quinic acid, salicylic acid, malic acid, citric acid, tartaric acid and alginic acid. In one embodiment provided by the present invention, the polybasic organic acids are salicylic acid and malic acid, and the mass ratio of salicylic acid to malic acid is preferably 12:(7-25), more preferably 12:13; in one embodiment provided by the present invention, the polybasic organic acids are citric acid and tartaric acid, and the mass ratio of citric acid to tartaric acid is preferably 1:(0.5-2), more preferably 1:1; in one embodiment provided by the present invention, the polybasic organic acids are malic acid, tartaric acid and alginic acid, and the mass ratio of malic acid, tartaric acid and alginic acid is preferably 1:(0.5-2):(0.5-2), more preferably 1:1:1.

[0041] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, based on 100 parts by weight of biomass powder, the amount of the polybasic organic acid is preferably 20 to 30 parts by weight, specifically 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, 25 parts by weight, 26 parts by weight, 27 parts by weight, 28 parts by weight, 29 parts by weight or 30 parts by weight.

[0042] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the heating reaction is preferably carried out under sealed conditions; the organic solvent used in the heating reaction is preferably ethanol, more preferably anhydrous ethanol; based on 100 parts by weight of the biomass powder, the amount of the organic solvent is preferably 300 to 600 parts by weight, specifically 300 parts by weight, 350 parts by weight, 400 parts by weight, 450 parts by weight, 500 parts by weight, 550 parts by weight or 600 parts by weight.

[0043] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the persulfate is preferably one or more of ammonium persulfate, potassium persulfate, and sodium persulfate. In one embodiment provided by the present invention, the persulfate is potassium persulfate and sodium persulfate, and the mass ratio of potassium sulfate to sodium persulfate is preferably 2: (0.5-3), more preferably 2:1.5; in one embodiment provided by the present invention, the persulfate is ammonium persulfate and sodium persulfate, and the mass ratio of ammonium persulfate to sodium persulfate is preferably 1: (0.5-2), more preferably 1:1.

[0044] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, based on 100 parts by weight of the biomass powder, the amount of the persulfate is preferably 200 to 400 parts by weight, specifically 200 parts by weight, 210 parts by weight, 220 parts by weight, 230 parts by weight, 240 parts by weight, 250 parts by weight, 260 parts by weight, 270 parts by weight, 280 parts by weight, 290 parts by weight, 300 parts by weight, 310 parts by weight, 320 parts by weight, 330 parts by weight, 340 parts by weight, 350 parts by weight, 360 parts by weight, 370 parts by weight, 380 parts by weight, 390 parts by weight or 400 parts by weight.

[0045] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the hydrothermal reaction is carried out in a closed reactor, and the water used in the hydrothermal reaction includes but is not limited to one or more of tap water, high-purity water, deionized water and distilled water; based on 100 parts by weight of the biomass powder, the amount of water used in the hydrothermal reaction is preferably 1000 to 3000 parts by weight, specifically 1000 parts by weight, 1200 parts by weight, 1500 parts by weight, 1700 parts by weight, 2000 parts by weight, 2300 parts by weight, 2500 parts by weight, 2700 parts by weight or 3000 parts by weight.

[0046] In the biomass-inorganic nanoparticle composite carbon spheres provided by the present invention, the mesh number of the biomass-inorganic nanoparticle composite carbon spheres is preferably 800-1000 mesh, specifically 800 mesh, 810 mesh, 820 mesh, 830 mesh, 840 mesh, 850 mesh, 860 mesh, 870 mesh, 880 mesh, 890 mesh, 900 mesh, 910 mesh, 920 mesh, 930 mesh, 940 mesh, 950 mesh, 960 mesh, 970 mesh, 980 mesh, 990 mesh or 1000 mesh.

[0047] The present invention also provides a method for preparing the biomass-inorganic nanoparticle composite carbon spheres described in the above technical solution, comprising the following steps:

[0048] a) heating the inorganic nanoparticles and the polybasic organic acid in an organic solvent to react, and filtering to obtain polybasic organic acid-etched nanoparticles and an organic acid filtrate, respectively;

[0049] b) subjecting the multi-organic acid corrosive nanoparticles, biomass powder and persulfate to a hydrothermal reaction under microwave assistance; after the reaction is completed, washing and drying the reaction product to obtain a dried material;

[0050] c) calcining the dried material in the absence of oxygen to obtain a pyrolysis material;

[0051] d) mixing the pyrolysis material with the organic acid filtrate and subjecting them to ultrasonic reaction; after the reaction is completed, washing, drying and grinding the reaction product to obtain biomass-inorganic nanoparticle composite carbon spheres.

[0052] In the preparation method provided by the present invention, in step a), the specific types and usage ratios of the inorganic nanoparticles, polybasic organic acid and organic solvent have been introduced above and will not be repeated here.

[0053] In the preparation method provided by the present invention, in step a), the heating reaction is preferably carried out under sealed conditions; the temperature of the heating reaction is preferably 50-70°C, specifically 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C, 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C; the stirring speed of the heating reaction is preferably 80-100 rpm, specifically 80 rpm, 81 rpm, 82 rpm, 83 rpm, 84 rpm, 85 rpm, 86 rpm rpm, 87rpm, 88rpm, 89rpm, 90rpm, 91rpm, 92rpm, 93rpm, 94rpm, 95rpm, 96rpm, 97rpm, 98rpm, 99rpm or 100rpm; the heating reaction time is preferably 1 to 3h, specifically 1h, 1.1h, 1.2h, 1.3h, 1.4h, 1.5h, 1.6h, 1.7h, 1.8h, 1.9h, 2h, 2.1h, 2.2h, 2.3h, 2.4h, 2.5h, 2.6h, 2.7h, 2.8h, 2.9h or 3h.

[0054] In the preparation method provided by the present invention, in step b), the specific types and usage ratios of the biomass powder and persulfate have been introduced above and will not be repeated here.

[0055] In the preparation method provided by the present invention, in step b), the hydrothermal reaction is carried out in a closed reactor with microwave-assisted function; the microwave power of the microwave-assisted reaction is preferably 800-1200W, specifically 800W, 850W, 900W, 950W, 1000W, 1050W, 1100W, 1150W or 1200W; the temperature of the hydrothermal reaction is preferably 220-240°C, specifically 220°C, 221°C, 222°C, 223°C, 224°C, 225°C, 226°C, 227°C, 228°C, 229°C, 230°C, 231°C, 232°C, 233°C, 234°C, 236°C, 237°C, 238°C, 239°C, 240°C, 241°C, 242°C, 243°C, 244°C, 245°C ℃, 23℃, 224℃, 225℃, 226℃, 227℃, 228℃, 229℃, 230℃, 231℃, 232℃, 233℃, 234℃, 235℃, 236℃, 237℃, 238℃, 239℃ or 240℃; the hydrothermal reaction time is preferably 12 to 24h, specifically 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h or 24h.

[0056] In the preparation method provided by the present invention, in step b), the reaction product is a solid material obtained by filtration after the reaction is completed; the washing is preferably water washing; the drying method is preferably oven drying, and the drying temperature is preferably 60-80°C, specifically 60°C, 65°C, 70°C, 75°C or 80°C.

[0057] In the preparation method provided by the present invention, in step c), the oxygen-free calcination is preferably carried out in an inert gas atmosphere, and the inert gas is preferably argon; the temperature of the oxygen-free calcination is preferably 450-550°C, specifically 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 510°C, 520°C, 530°C, 540°C or 550°C; the time of the oxygen-free calcination is preferably 60-100 min, specifically 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, 95 min or 100 min. In the present invention, the heating rate before reaching the temperature is preferably 5 to 10°C / min, specifically 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min or 10°C / min; the cooling rate after completion of the oxygen-free calcination is preferably 5 to 10°C / min, specifically 5°C / min, 6°C / min, 7°C / min, 8°C / min, 9°C / min or 10°C / min.

[0058] In the preparation method provided by the present invention, in step d), the ultrasonic frequency of the ultrasonic reaction is preferably 40-60 KHz, specifically 40 KHz, 41 KHz, 42 KHz, 43 KHz, 44 KHz, 45 KHz, 46 KHz, 47 KHz, 48 KHz, 49 KHz, 50 KHz, 51 KHz, 52 KHz, 53 KHz, 54 KHz, 55 KHz, 56 KHz, 57 KHz, 58 KHz, 59 KHz or 60 KHz; the temperature of the ultrasonic reaction is preferably 60-80 ° C, specifically 60 ° C, 61 ° C, 62 ° C, 63 ° C, 64 ° C, the ultrasonic reaction time is preferably 20 to 40 min, specifically 20 min, 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min, 30 min, 31 min, 32 min, 33 min, 34 min, 35 min, 36 min, 37 min, 38 min, 39 min or 40 min.

[0059] In the preparation method provided by the present invention, in step d), the reaction product is a solid material obtained by filtration after the reaction is completed; the washing is preferably water washing; the drying method is preferably oven drying, and the drying temperature is preferably 60-80°C, specifically 60°C, 65°C, 70°C, 75°C or 80°C; the grinding method is preferably ball milling.

[0060] The present invention also provides a heat-resistant antistatic composite material, which is made by melt blending raw materials, wherein the raw materials include biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant and a chain extender;

[0061] The biomass-inorganic nanoparticle composite carbon spheres are the biomass-inorganic nanoparticle composite carbon spheres described in the above technical solution or the biomass-inorganic nanoparticle composite carbon spheres prepared by the preparation method described in the above technical solution.

[0062] In the heat-resistant antistatic composite material provided by the present invention, the weight-average molecular weight of the polylactic acid is preferably 200,000 to 400,000, specifically 200,000, 210,000, 220,000, 230,000, 240,000, 250,000, 260,000, 270,000, 280,000, 290,000, 300,000, 310,000, 320,000, 330,000, 340,000, 350,000, 360,000, 370,000, 380,000, 390,000 or 400,000.

[0063] In the heat-resistant antistatic composite material provided by the present invention, based on 100 parts by weight of the raw material biomass powder for preparing the biomass-inorganic nanoparticle composite carbon balls, the amount of the polylactic acid is preferably 200 to 400 parts by weight, specifically 200 parts by weight, 210 parts by weight, 220 parts by weight, 230 parts by weight, 240 parts by weight, 250 parts by weight, 260 parts by weight, 270 parts by weight, 280 parts by weight, 290 parts by weight, 300 parts by weight, 310 parts by weight, 320 parts by weight, 330 parts by weight, 340 parts by weight, 350 parts by weight, 360 parts by weight, 370 parts by weight, 380 parts by weight, 390 parts by weight or 400 parts by weight.

[0064] In the heat-resistant antistatic composite material provided by the present invention, the molar ratio of the aliphatic polyester (BA) repeating unit to the aromatic polyester (BT) repeating unit in the polybutylene adipate-terephthalate is preferably (60:40) to (40:60), specifically 60:40, 55:45, 50:50, 45:55 or 40:60; the weight-average molecular weight of the polybutylene adipate-terephthalate is preferably 150,000 to 250,000, specifically 150,000, 155,000, 160,000, 165,000, 170,000, 175,000, 180,000, 185,000, 190,000, 195,000, 200,000, 205,000, 210,000, 215,000, 220,000, 225,000, 230,000, 235,000, 240,000, 245,000 or 250,000.

[0065] In the heat-resistant antistatic composite material provided by the present invention, based on 100 parts by weight of the raw material biomass powder for preparing the biomass-inorganic nanoparticle composite carbon balls, the amount of the polybutylene adipate-terephthalate is preferably 40 to 45 parts by weight, specifically 40 parts by weight, 40.5 parts by weight, 41 parts by weight, 41.5 parts by weight, 42 parts by weight, 42.5 parts by weight, 43 parts by weight, 43.5 parts by weight, 44 parts by weight, 44.5 parts by weight or 45 parts by weight.

[0066] In the heat-resistant antistatic composite material provided by the present invention, the organic nucleating agent is preferably one or more of phenyl zinc phosphate, 2,2'-methylenebis(4,6-di-tert-butylphenyl) sodium phosphate, sodium benzoate, diphenyl adipate dihydrazide, sebacic acid dibenzohydrazide, ethylene bisstearamide, N,N-diethylene bis(1,2-hydroxy)stearamide and dibenzoyl adipate. In one embodiment provided by the present invention, the organic nucleating agent is phenyl zinc phosphate and sodium benzoate, and the mass ratio of the phenyl zinc phosphate and sodium benzoate is preferably 3: (3 to 5), more preferably 3: 4; in one embodiment provided by the present invention, the organic nucleating agent is diphenyl dihydrazide adipic acid and dibenzoyl sebacic acid, and the mass ratio of diphenyl dihydrazide adipic acid and dibenzoyl sebacic acid is preferably 4: (3 to 7), more preferably 4: 5; in one embodiment provided by the present invention, the organic nucleating agent is sodium benzoate, ethylene bisstearamide and dibenzoyl adipate, and the mass ratio of sodium benzoate, ethylene bisstearamide and dibenzoyl adipate is preferably 3: (1 to 5): (2 to 6), more preferably 3: 3: 4.

[0067] In the heat-resistant antistatic composite material provided by the present invention, based on 100 parts by weight of the raw biomass powder for preparing the biomass-inorganic nanoparticle composite carbon balls, the amount of the organic nucleating agent is preferably 0.5 to 1 part by weight, specifically 0.5 part by weight, 0.55 part by weight, 0.6 part by weight, 0.65 part by weight, 0.7 part by weight, 0.75 part by weight, 0.8 part by weight, 0.85 part by weight, 0.9 part by weight, 0.95 part by weight or 1 part by weight.

[0068] In the heat-resistant antistatic composite material provided by the present invention, the dispersant is preferably one or more of calcium stearate, stearic acid, zinc stearate and polyethylene wax, and the polyethylene wax is preferably polyethylene wax OA9. In one embodiment provided by the present invention, the dispersant is stearic acid and polyethylene wax, and the mass ratio of the stearic acid and polyethylene wax is preferably 1: (0.5-2), more preferably 1: 1; in one embodiment provided by the present invention, the dispersant is stearic acid and calcium stearate, and the mass ratio of the stearic acid and calcium stearate is preferably 7: (3-15), more preferably 7: 8; in one embodiment provided by the present invention, the dispersant is polyethylene wax and calcium stearate, and the mass ratio of the polyethylene wax and calcium stearate is preferably 1: (0.5-2), more preferably 1: 1.

[0069] In the heat-resistant antistatic composite material provided by the present invention, based on 100 parts by weight of the raw material biomass powder for preparing the biomass-inorganic nanoparticle composite carbon balls, the amount of the dispersant is preferably 0.5 to 2 parts by weight, specifically 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight, 1.5 parts by weight, 1.6 parts by weight, 1.7 parts by weight, 1.8 parts by weight, 1.9 parts by weight or 2 parts by weight.

[0070] In the heat-resistant antistatic composite material provided by the present invention, the chain extender is preferably one or more of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, pyromellitic anhydride (PMDA), styrene-glycidyl methacrylate copolymer (SG) and ethylene-methyl methacrylate copolymer (EMMA). In one embodiment provided by the present invention, the chain extender is styrene-methyl methacrylate copolymer and ethylene-methyl methacrylate copolymer, and the mass ratio of the styrene-methyl methacrylate copolymer and the ethylene-methyl methacrylate copolymer is preferably 1: (0.5-2), more preferably 1: 1; in one embodiment provided by the present invention, the chain extender is ethylene-methyl methacrylate copolymer and pyromellitic anhydride, and the mass ratio of the ethylene-methyl methacrylate copolymer and pyromellitic anhydride is preferably 2: (0.5-3), more preferably 2: 1.5; in one embodiment provided by the present invention, the chain extender is ethylene-methyl methacrylate copolymer, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and styrene-methyl methacrylate copolymer, and the mass ratio of the ethylene-methyl methacrylate copolymer, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and styrene-methyl methacrylate copolymer is preferably 1: (0.5-2): (1-3), more preferably 1: 1: 2.

[0071] In the heat-resistant antistatic composite material provided by the present invention, based on 100 parts by weight of the raw biomass powder for preparing the biomass-inorganic nanoparticle composite carbon spheres, the amount of the chain extender is preferably 0.2 to 0.4 parts by weight, specifically 0.2 parts by weight, 0.21 parts by weight, 0.22 parts by weight, 0.23 parts by weight, 0.24 parts by weight, 0.25 parts by weight, 0.26 parts by weight, 0.27 parts by weight, 0.28 parts by weight, 0.29 parts by weight, 0.3 parts by weight, 0.31 parts by weight, 0.32 parts by weight, 0.33 parts by weight, 0.34 parts by weight, 0.35 parts by weight, 0.36 parts by weight, 0.37 parts by weight, 0.38 parts by weight, 0.39 parts by weight or 0.4 parts by weight.

[0072] The present invention also provides a method for preparing the heat-resistant antistatic composite material described in the above technical solution, comprising the following steps:

[0073] Biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant and a chain extender are melt-blended to obtain a heat-resistant antistatic composite material.

[0074] In the preparation method of the heat-resistant antistatic composite material provided by the present invention, the specific types and usage ratios of the polylactic acid, polybutylene adipate-terephthalate, organic nucleating agent, dispersant and chain extender have been introduced above and will not be repeated here.

[0075] In the preparation method of the heat-resistant antistatic composite material provided by the present invention, before the melt blending, the biomass-inorganic nanoparticle composite carbon balls, polylactic acid, polybutylene adipate-terephthalate, organic nucleating agent, dispersant and chain extender are preferably mixed evenly; the mixing speed is preferably 600-800 rpm, specifically 600 rpm, 650 rpm, 700 rpm, 750 rpm or 800 rpm; the mixing temperature is preferably 15-35°C, specifically 25°C (room temperature); the mixing time is preferably 10-30 min, specifically 10 min, 15 min, 20 min, 25 min or 30 min.

[0076] In the method for preparing a heat-resistant antistatic composite material provided by the present invention, the melt blending is preferably carried out in a screw extruder; the extrusion speed of the screw extruder is preferably 100 to 200 rpm, specifically 100 rpm, 110 rpm, 120 rpm, 130 rpm, 140 rpm, 150 rpm, 160 rpm, 170 rpm, 180 rpm, 190 rpm or 200 rpm; The temperature of the mixing section of the screw extruder is preferably 180-190°C, specifically 180°C, 181°C, 182°C, 183°C, 184°C, 185°C, 186°C, 187°C, 188°C, 189°C or 190°C; the temperature of the extrusion section of the screw extruder is preferably 160-170°C, specifically 160°C, 161°C, 162°C, 163°C, 164°C, 165°C, 165°C, 166°C, 167°C, 168°C, 169°C or 170°C.

[0077] In the preparation method of the heat-resistant antistatic composite material provided by the present invention, after the melt blending is completed, the obtained material is preferably dried, and the drying method is preferably oven drying, and the drying temperature is preferably 60-80°C, specifically 60°C, 65°C, 70°C, 75°C or 80°C.

[0078] The biomass-inorganic nanoparticle composite carbon spheres, their preparation method, heat-resistant antistatic composite material and their preparation method provided by the present invention have at least the following advantages:

[0079] 1) Ammonium persulfate is used to promote biomass hydrolysis, and microwave-assisted heating and heterogeneous nucleation are used to accelerate the carbon sphere conversion process, thereby improving the conversion efficiency of carbon materials, simplifying the process, and reducing costs. The prepared composite carbon spheres, a compounded nucleating agent, and polylactic acid raw materials are reactively melt-blended to prepare a composite material with better compatibility, thereby achieving the comprehensive utilization of agricultural and forestry wastes.

[0080] 2) The composite carbon ball material obtained according to the method of the present invention has high application value, good compatibility with the composite material prepared from polylactic acid, excellent mechanical properties, good heat resistance, and can be used in the fields of antistatic materials.

[0081] 3) Compared with existing methods, the technical solution provided by the present invention uses persulfate to catalyze the hydrothermal carbonization process, and utilizes microwave-assisted heating and heterogeneous nucleation to synergistically promote the reaction process, thereby increasing the yield of carbon ball materials. The process is relatively simple and the entire process is safe and environmentally friendly.

[0082] 4) The technical solution provided by the present invention is simple and efficient, has high production efficiency, can be produced on a large scale, and provides a feasible solution for the comprehensive utilization of agricultural and forestry wastes.

[0083] For the purpose of greater clarity, the present invention is described in detail with reference to the following examples and comparative examples.

[0084] In the following examples and comparative examples of the present invention, the specific evaluation methods of the materials are as follows:

[0085] 1) Yield:

[0086] Use an analytical balance to measure the total weight of the biomass raw materials and the prepared biomass-inorganic nanoparticle composite carbon balls respectively. Then, use the same experimental operation to conduct a comparative experiment using only inorganic nanoparticles. By calculating the weight of the inorganic nanoparticles, the yield of the biomass carbon material is estimated, and then the average value of multiple experiments is taken.

[0087] 2) Micromorphology:

[0088] The obtained biomass-inorganic nanoparticle composite carbon spheres were carefully ground, the ground powder was ultrasonically treated in anhydrous ethanol, and then dropped onto a copper mesh. After the alcohol evaporated, the copper mesh was glued to the sample stage, and its morphology and diffraction ring images were observed using a transmission electron microscope.

[0089] 3) Volume resistance:

[0090] The composite material was compression molded at 180°C and 10 MPa, and cooled under pressure to obtain a sheet with a specification of 120 mm × 100 mm × 2 mm. The volume resistivity of the composite material was measured at room temperature using a high resistance meter. Five groups were tested in parallel, and the results were taken as the average of the five groups of data.

[0091] 4) Vicat softening temperature:

[0092] The composite material was molded under the conditions of 180℃ and 10MPa, cooled under pressure to obtain a 4mm sheet, which was then cut into 10mm×10mm×4mm specimens. 120 The Vicat softening temperature was determined by the method with a heating rate of 120°C / h, silicone oil as the heating medium, and a loading load of 50N.

[0093] 5) Tensile properties:

[0094] The composite material was compression molded at 180°C and 10 MPa for 2 min, cooled under pressure to obtain a 1 mm sheet, which was then cut into a dumbbell shape of 20 mm × 4 mm × 1 mm. It was tested using a universal tensile testing machine according to ASTM D63-2014 at a tensile speed of 10 mm / min. Five groups of parallel measurements were taken, and the results were averaged.

[0095] Example 1

[0096] First, 5 parts by weight of 50nm silica, 20 parts by weight of quinic acid and 400 parts by weight of anhydrous ethanol were placed in a large beaker, sealed with plastic wrap, and heated in a magnetic stirring water bath for 2 hours at a stirring speed of 80 rpm and a reaction temperature of 50°C. After the reaction, rapid filtration was performed using a vacuum filter to separately preserve the organic acid-corroded silica and the organic acid filtrate.

[0097] Then the organic acid-etched silica, 100 parts by weight of 400-mesh jute powder, 200 parts by weight of potassium persulfate and 2000 parts by weight of tap water were placed in a microwave high-pressure reactor for hydrothermal reaction for 12 hours, the hydrothermal reaction temperature was 220°C, and the microwave power was 800W; after the reaction, it was quickly filtered with a vacuum filter and repeatedly washed with deionized water until the upper liquid changed from black to colorless, and the washed product was placed in an oven and dried at 60°C to obtain a dried material; then the dried material was placed in a high-temperature pure argon atmosphere furnace and heated at 5°C / m in was heated to 450°C at a heating rate, calcined at a constant temperature for 60 minutes, and then cooled to room temperature at a cooling rate of 5°C / min to obtain a pyrolysis material; the pyrolysis material and the above-mentioned organic acid filtrate were then placed in a large beaker and reacted in a water bath in an ultrasonic machine for 20 minutes, the ultrasonic frequency was 40KHz, and the water bath temperature was 60°C; finally, it was quickly filtered with a vacuum filter and repeatedly washed with deionized water. The washed product was placed in an oven and dried at 60°C, and then ground into 800 mesh in a ball mill; the obtained biomass-inorganic nanoparticle composite carbon balls were weighed and recorded.

[0098] The above-mentioned biomass-inorganic nanoparticle composite carbon spheres are placed in a high-speed mixer, and 400 parts by weight of polylactic acid with a weight average molecular weight of 200,000 and 40 parts by weight of polybutylene adipate terephthalate with a weight average molecular weight of 150,000 (the molar ratio of BA to BT is 60:40) are added, and then 0.5 parts by weight of phenyl zinc phosphate, 0.5 parts by weight of calcium stearate, and 0.2 parts by weight of ethylene-methyl methacrylate copolymer with a weight average molecular weight of 25,000 (the molar ratio of ethylene repeating units to methyl methacrylate repeating units is 4:1) are added, and mixed at room temperature for 10 minutes, and the speed is set to 600 rpm; then the mixed materials are melt-blended and extruded into granules in a twin-screw extruder, the blending temperature is set to 180°C, the extrusion temperature is set to 160°C, and the screw extrusion speed is 100 rpm; finally, the obtained pellets are dried at 60°C to obtain a heat-resistant antistatic composite material.

[0099] The test results show that the yield of carbon materials in the composite carbon balls is 14.1%; the volume resistivity of the heat-resistant antistatic composite material is 3.25×10 8 Ω / sq., Vicat softening temperature is 79.8℃, and tensile properties are shown in Table 1.

[0100] Example 2

[0101] First, 6 parts by weight of 60nm titanium dioxide, 23 parts by weight of malic acid and 400 parts by weight of anhydrous ethanol were placed in a large beaker, sealed with plastic wrap, and heated in a magnetic stirring water bath for 2 hours at a stirring speed of 85 rpm and a reaction temperature of 55°C. After the reaction, rapid filtration was performed using a vacuum filter to separately preserve the organic acid-corroded titanium dioxide and the organic acid filtrate.

[0102] Then the organic acid-etched titanium dioxide, 100 parts by weight of 450-mesh peanut shell powder, 250 parts by weight of ammonium persulfate and 2000 parts by weight of high-purity water were placed in a microwave high-pressure reactor for hydrothermal reaction for 15 hours, the hydrothermal reaction temperature was 225°C, and the microwave power was 900W; after the reaction, it was quickly filtered with a vacuum filter and repeatedly washed with deionized water until the upper liquid changed from black to colorless, and the washed product was placed in an oven and dried at 65°C to obtain a dried material; then the dried material was placed in a high-temperature pure argon atmosphere furnace and heated at 6°C / m in was heated to 475°C at a heating rate, calcined at a constant temperature for 70 minutes, and then cooled to room temperature at a cooling rate of 6°C / min to obtain a pyrolysis material; the pyrolysis material and the above-mentioned organic acid filtrate were then placed in a large beaker and reacted in a water bath in an ultrasonic machine for 25 minutes, the ultrasonic frequency was 45KHz, and the water bath temperature was 65°C; finally, it was quickly filtered with a vacuum filter and repeatedly washed with deionized water. The washed product was placed in an oven and dried at 65°C, and then ground into 850 mesh in a ball mill; the mass of the obtained biomass-inorganic nanoparticle composite carbon balls was weighed and recorded.

[0103] The above-mentioned biomass-inorganic nanoparticle composite carbon spheres are placed in a high-speed mixer, and 350 parts by weight of polylactic acid with a weight average molecular weight of 250,000 and 44 parts by weight of polybutylene adipate terephthalate with a weight average molecular weight of 170,000 (the molar ratio of BA to BT is 55:45) are added, and then 0.6 parts by weight of 2,2'-methylenebis(4,6-di-tert-butylphenyl) sodium phosphate, 0.8 parts by weight of stearic acid, and 0.25 parts by weight of pyromellitic anhydride are added. The mixture is mixed at room temperature for 15 minutes, and the speed is set to 650 rpm; then the mixed materials are melt-blended and extruded into granules in a twin-screw extruder, the blending temperature is set to 182°C, the extrusion temperature is set to 162°C, and the screw extrusion speed is 125 rpm; finally, the obtained pellets are dried at 65°C to obtain a heat-resistant antistatic composite material.

[0104] The transmission diagram and diffraction rings of Experiment 2 are shown in Figure 2. Figure 1 and Figure 2 As shown, in Figure 1It can be seen that the prepared biomass-inorganic nanoparticle composite carbon spheres are in the form of agglomerated nanospheres and larger microspheres, which are typical characteristics of the biomass carbon sphere nucleus and growth process. Among them, obvious small black spots can be seen in the light-colored area, corresponding to titanium dioxide, indicating the formation of a core-shell structure and a cross-linked structure in which titanium dioxide is embedded. Figure 2 This is a picture of the characteristic diffraction rings of titanium dioxide, indicating that titanium dioxide is indeed compounded in the carbon spheres.

[0105] The test results show that the yield of carbon materials in the composite carbon balls is 14.3%; the volume resistivity of the heat-resistant antistatic composite material is 8.58×10 7 Ω / sq., Vicat softening temperature is 84.3℃, and tensile properties are shown in Table 1.

[0106] Example 3

[0107] First, 3 parts by weight of 70nm titanium dioxide, 4 parts by weight of 70nm talc, 12 parts by weight of salicylic acid, 13 parts by weight of malic acid and 400 parts by weight of anhydrous ethanol were placed in a large beaker, sealed with plastic wrap, and heated in a magnetic stirring water bath for 2 hours at a stirring speed of 90 rpm and a reaction temperature of 60°C. After the reaction, rapid filtration was performed using a vacuum filter to preserve the organic acid-corroded inorganic nanoparticles and the organic acid filtrate, respectively.

[0108] Then the above-mentioned organic acid-etched inorganic nanoparticles, 50 parts by weight of 500-mesh pine cone powder and 50 parts by weight of 500-mesh coconut shell powder, 300 parts by weight of sodium persulfate and 2000 parts by weight of deionized water are placed in a microwave high-pressure reactor for hydrothermal reaction for 18 hours, the hydrothermal reaction temperature is 230°C, and the microwave power is 1000W; after the reaction is completed, it is quickly filtered with a vacuum filter and repeatedly washed with deionized water until the upper liquid changes from black to colorless, and the washed product is placed in an oven and dried at 70°C to obtain a dried material; then the dried material is placed in a high-temperature pure argon atmosphere In the furnace, the temperature was raised to 500°C at a heating rate of 7°C / min, calcined at a constant temperature for 70 minutes, and then cooled to room temperature at a cooling rate of 7°C / min to obtain a pyrolysis material; the pyrolysis material and the above-mentioned organic acid filtrate were then placed in a large beaker and reacted in a water bath in an ultrasonic machine for 30 minutes, the ultrasonic frequency was 50KHz, and the water bath temperature was 70°C; finally, a vacuum filter was used for rapid filtration, and the product was repeatedly washed with deionized water. The washed product was placed in an oven and dried at 70°C, and then ground into 900 mesh in a ball mill; the mass of the obtained biomass-inorganic nanoparticle composite carbon balls was weighed and recorded.

[0109] The above-mentioned biomass-inorganic nanoparticle composite carbon spheres were placed in a high-speed blender, and 300 parts by weight of polylactic acid with a weight average molecular weight of 300,000, 45 parts by weight of polybutylene adipate-terephthalate with a weight average molecular weight of 200,000 (the molar ratio of BA to BT was 50:50) were added, and then 0.3 parts by weight of zinc phenyl phosphate, 0.4 parts by weight of sodium benzoate, 0.6 parts by weight of stearic acid and 0.6 parts by weight of polyethylene wax OA9, 0.15 parts by weight of styrene-methacrylate glycidyl copolymer with a weight average molecular weight of 18,000 (styrene repeating units and methacrylic acid glycidyl ester copolymer) were added. The present invention relates to a method for preparing a heat-resistant antistatic composite material comprising the steps of: preparing a mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following: a first step of preparing the mixture of the following: preparing the mixture of the following:

[0110] The test results show that the yield of carbon materials in the composite carbon spheres is 14.4%; the volume resistivity of the heat-resistant antistatic composite material is 6.55×10 6 Ω / sq., Vicat softening temperature is 88.7℃, and tensile properties are shown in Table 1.

[0111] Example 4

[0112] First, 4 parts by weight of 85nm talc, 4 parts by weight of 85nm montmorillonite, 13 parts by weight of citric acid, 13 parts by weight of tartaric acid and 400 parts by weight of anhydrous ethanol were placed in a large beaker, sealed with plastic wrap, and heated in a magnetic stirring water bath for 2 hours at a stirring speed of 90 rpm and a reaction temperature of 65°C. After the reaction, rapid filtration was performed using a vacuum filter to preserve the organic acid-corroded inorganic nanoparticles and the organic acid filtrate, respectively.

[0113] Then, the above-mentioned organic acid-etched inorganic nanoparticles, 50 parts by weight of 550-mesh nut shell powder and 50 parts by weight of 550-mesh jute powder, 200 parts by weight of potassium persulfate, 150 parts by weight of sodium persulfate and 2000 parts by weight of distilled water are placed in a microwave high-pressure reactor for hydrothermal reaction for 21 hours, the hydrothermal reaction temperature is 235°C, and the microwave power is 1100W; after the reaction is completed, it is quickly filtered with a vacuum filter and repeatedly washed with deionized water until the upper liquid changes from black to colorless, and the washed product is placed in an oven and dried at 75°C to obtain a dried material; then the dried material is placed in a high-temperature In a pure argon atmosphere furnace, the temperature was raised to 525°C at a heating rate of 9°C / min, calcined at a constant temperature for 90 minutes, and then cooled to room temperature at a cooling rate of 9°C / min to obtain a pyrolysis material; the pyrolysis material and the above-mentioned organic acid filtrate were then placed in a large beaker and reacted in a water bath in an ultrasonic machine for 35 minutes, with an ultrasonic frequency of 55KHz and a water bath temperature of 75°C; finally, a vacuum filter was used for rapid filtration, and the product was repeatedly washed with deionized water. The washed product was placed in an oven and dried at 75°C, and then ground into 900 mesh in a ball mill; the mass of the obtained biomass-inorganic nanoparticle composite carbon balls was weighed and recorded.

[0114] The above-mentioned biomass-inorganic nanoparticle composite carbon spheres were placed in a high-speed blender, and 250 parts by weight of polylactic acid with a weight average molecular weight of 350,000, 44 parts by weight of polybutylene adipate terephthalate with a weight average molecular weight of 220,000 (the molar ratio of BA to BT was 45:55) were added, and then 0.4 parts by weight of diphenyl dihydrazide adipic acid, 0.5 parts by weight of dibenzoyl sebacic acid, 0.7 parts by weight of stearic acid, 0.8 parts by weight of calcium stearate, 0.2 parts by weight of ethylene-methylene terephthalate with a weight average molecular weight of 25,000 were added. The present invention relates to a methyl methacrylate copolymer (the molar ratio of ethylene repeating units to methyl methacrylate repeating units is 4:1), and then 0.15 weight parts of pyromellitic anhydride are added, and the mixture is mixed at room temperature for 25 minutes, and the speed is set to 750 rpm; then the mixed materials are melt-blended and extruded into granules in a twin-screw extruder, the blending temperature is set to 187°C, the extrusion temperature is set to 167°C, and the screw extrusion speed is 175 rpm; finally, the obtained pellets are dried at 75°C to obtain a heat-resistant antistatic composite material.

[0115] The test results show that the yield of carbon materials in the composite carbon balls is 14.7%; the volume resistivity of the heat-resistant antistatic composite material is 9.31×10 5 Ω / sq., Vicat softening temperature is 92.1℃, and tensile properties are shown in Table 1.

[0116] Example 5

[0117] First, 3 parts by weight of 100nm kaolin, 3 parts by weight of 100nm titanium dioxide, 4 parts by weight of 100nm hydroxyapatite, 10 parts by weight of malic acid, 10 parts by weight of tartaric acid, 10 parts by weight of alginic acid and 400 parts by weight of anhydrous ethanol were placed in a large beaker, sealed with plastic wrap, and heated in a magnetic stirring water bath for reaction for 2h at a stirring speed of 100rpm and a reaction temperature of 70°C; after the reaction, rapid filtration was performed using a vacuum filter to preserve the organic acid-etched inorganic nanoparticles and the organic acid filtrate, respectively.

[0118] Then, the above-mentioned organic acid-corroded inorganic nanoparticles, 30 parts by weight of 600-mesh sunflower stem powder, 30 parts by weight of 600-mesh peanut shell powder, 40 parts by weight of 600-mesh rice straw powder, 200 parts by weight of ammonium persulfate, 200 parts by weight of sodium persulfate, 1000 parts by weight of deionized water and 1000 parts by weight of distilled water are placed in a microwave high-pressure reactor for hydrothermal reaction for 24 hours, the hydrothermal reaction temperature is 240°C, and the microwave power is 1200W; after the reaction is completed, it is quickly filtered with a vacuum filter and repeatedly washed with deionized water until the upper liquid changes from black to colorless, and the washed product is placed in an oven and dried at 80°C to obtain a dried product. dry material; then place the dried material in a high-temperature pure argon atmosphere furnace, heat it to 550°C at a heating rate of 10°C / min, calcine at a constant temperature for 100 minutes, and then cool it to room temperature at a cooling rate of 10°C / min to obtain a pyrolysis material; then place the pyrolysis material and the above-mentioned organic acid filtrate in a large beaker, react in an ultrasonic machine in a water bath for 40 minutes, the ultrasonic frequency is 60KHz, and the water bath temperature is 80°C; finally, use a vacuum filter to quickly filter, repeatedly wash with deionized water, place the washed product in an oven to dry at 80°C, and then grind it to 1000 mesh in a ball mill; weigh the mass of the obtained biomass-inorganic nanoparticle composite carbon balls and record it.

[0119] The above-mentioned biomass-inorganic nanoparticle composite carbon spheres are placed in a high-speed blender, and 200 parts by weight of polylactic acid with a weight average molecular weight of 400,000, 40 parts by weight of polybutylene adipate-terephthalate with a weight average molecular weight of 250,000 (the molar ratio of BA to BT is 40:60) are added, and then 0.3 parts by weight of sodium benzoate, 0.3 parts by weight of ethylene bisstearamide, 0.4 parts by weight of dibenzoyl adipate, 1 part by weight of polyethylene wax OA9 and 1 part by weight of calcium stearate, 0.1 parts by weight of ethylene-methyl methacrylate copolymer with a weight average molecular weight of 25,000 (the molar ratio of ethylene repeating units to methyl methacrylate repeating units is 4:1) are added. ), 0.1 parts by weight of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and 0.2 parts by weight of a styrene-glycidyl methacrylate copolymer with a weight average molecular weight of 18,000 (the molar ratio of styrene repeating units to glycidyl methacrylate repeating units is 5:1), mixed at room temperature for 30 minutes, and the speed is set to 800 rpm; then the mixed materials are melt-blended and extruded into granules in a twin-screw extruder, the blending temperature is set to 190°C, the extrusion temperature is set to 170°C, the screw extrusion speed is 200 rpm, and finally the obtained pellets are dried at 80°C to obtain a heat-resistant antistatic composite material.

[0120] The test results show that the yield of carbon materials in the composite carbon balls is 15.1%; the volume resistivity of the heat-resistant antistatic composite material is 6.18×10 5 Ω / sq., Vicat softening temperature is 96.5℃, and tensile properties are shown in Table 1.

[0121] Comparative Example 1

[0122] First, 100 parts by weight of 400-mesh jute powder and 2000 parts by weight of tap water are placed in a high-pressure reactor for hydrothermal reaction for 12 hours at a hydrothermal reaction temperature of 220°C. After the reaction is completed, the mixture is quickly filtered using a vacuum filter and repeatedly washed with deionized water until the upper liquid changes from black to colorless. The washed product is placed in an oven and dried at 60°C to obtain a dried material. The dried material is then placed in a high-temperature pure argon atmosphere furnace, heated to 450°C at a heating rate of 5°C / min, and calcined at a constant temperature for 60 minutes. , and then cooled to room temperature at a rate of 5°C / min to obtain a pyrolysis material; then the pyrolysis material, 20 parts by weight of quinic acid and 400 parts by weight of anhydrous ethanol were placed in a large beaker, sealed with plastic wrap, and reacted in an ultrasonic machine in a water bath for 20 minutes, with an ultrasonic frequency of 40KHz and a water bath temperature of 60°C; finally, a vacuum filter was used for rapid filtration, and the product was repeatedly washed with deionized water. The washed product was placed in an oven and dried at 60°C, and then ground into 800 mesh in a ball mill; the mass of the obtained biomass carbon balls was weighed and recorded.

[0123] The above-mentioned biomass carbon balls are placed in a high-speed mixer, and 400 parts by weight of polylactic acid with a weight average molecular weight of 200,000 and 40 parts by weight of polybutylene adipate terephthalate with a weight average molecular weight of 150,000 (the molar ratio of BA to BT is 60:40) are added, and then 0.5 parts by weight of calcium stearate and 0.2 parts by weight of ethylene-methyl methacrylate copolymer with a weight average molecular weight of 25,000 (the molar ratio of ethylene repeating units to methyl methacrylate repeating units is 4:1) are added. The mixture is mixed at room temperature for 10 minutes, and the speed is set to 600 rpm; then the mixed materials are melt-blended and extruded into granules in a twin-screw extruder, the blending temperature is set to 180°C, the extrusion temperature is set to 160°C, and the screw extrusion speed is 100 rpm; finally, the obtained pellets are dried at 60°C to obtain a heat-resistant antistatic composite material.

[0124] The test showed that the yield of biomass carbon balls was 1.7% and the volume resistivity of the composite material was 1.25×10 11 Ω / sq., Vicat softening temperature is 67.5℃, and tensile properties are shown in Table 1.

[0125] Comparative Example 2

[0126] First, 100 parts by weight of 600-mesh jute powder, 400 parts by weight of potassium persulfate and 2000 parts by weight of tap water were taken and placed in a microwave high-pressure reactor for hydrothermal reaction for 24 hours. The hydrothermal reaction temperature was 240°C and the microwave power was 1200W. After the reaction, the mixture was quickly filtered with a vacuum filter and repeatedly washed with deionized water until the upper liquid turned from black to colorless. The washed product was placed in an oven and dried at 80°C to obtain a dried material. The dried material was then placed in a high-temperature pure argon atmosphere furnace and heated to 40°C at a heating rate of 5°C / min. 550℃, constant temperature calcination for 100min, and then cooling to room temperature at a rate of 5℃ / min to obtain a pyrolysis material; then the pyrolysis material, 30 parts by weight of quinic acid and 400 parts by weight of anhydrous ethanol are placed in a large beaker, and reacted in an ultrasonic machine in a water bath for 40min, the ultrasonic frequency is 60KHz, and the water bath temperature is 80℃; finally, it is quickly filtered with a vacuum filter, repeatedly washed with deionized water, and the washed product is placed in an oven and dried at 80℃, and then ground into 1000 mesh in a ball mill; the mass of the obtained biomass carbon balls is weighed and recorded.

[0127] The above-mentioned biomass carbon balls are placed in a high-speed mixer, and 10 parts by weight of silica, 200 parts by weight of polylactic acid with a weight average molecular weight of 200,000, and 40 parts by weight of polybutylene adipate terephthalate with a weight average molecular weight of 150,000 (the molar ratio of BA to BT is 60:40) are added, and then 1 part by weight of calcium stearate and 0.4 parts by weight of ethylene-methyl methacrylate copolymer with a weight average molecular weight of 25,000 (the molar ratio of ethylene repeating units to methyl methacrylate repeating units is 4:1) are added, and mixed at room temperature for 30 minutes, and the speed is set to 600 rpm; then the mixed materials are melt-blended and extruded into granules in a twin-screw extruder, the blending temperature is set to 190°C, the extrusion temperature is set to 170°C, and the screw extrusion speed is 200 rpm; finally, the obtained pellets are dried at 80°C to obtain a heat-resistant antistatic composite material.

[0128] The test showed that the yield of biomass carbon balls was 10.9% and the volume resistivity of the composite material was 9.62×10 9 Ω / sq., Vicat softening temperature is 78.9℃, and tensile properties are shown in Table 1.

[0129] Comparative Example 3

[0130] The weight average molecular weight of polylactic acid is 200,000. After testing, the volume resistivity of polylactic acid is 2.97×10 13 Ω / sq., Vicat softening temperature is 59.2℃, and tensile properties are shown in Table 1.

[0131] Table 1 Test results of tensile properties of composite materials of different embodiments and comparative examples

[0132]

[0133]

[0134] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A biomass-inorganic nanoparticle composite carbon sphere, which is prepared by hydrothermal reaction of polybasic organic acid corrosive nanoparticles, biomass powder and persulfate under microwave assistance, followed by washing, drying and oxygen-free calcination, and then ultrasonic reaction in polybasic organic acid solution, followed by washing, drying and grinding; The polybasic organic acid corrosive nanoparticles are prepared by heating inorganic nanoparticles and polybasic organic acid in an organic solvent and then filtering. The inorganic nanoparticles are one or more of titanium dioxide, silicon dioxide, talc, montmorillonite, kaolin, mica and hydroxyapatite; The polybasic organic acid is one or more of quinic acid, salicylic acid, malic acid, citric acid, tartaric acid and alginic acid; Based on 100 parts by weight of the biomass powder, the amount of the inorganic nanoparticles is 5 to 10 parts by weight, the amount of the polybasic organic acid is 20 to 30 parts by weight, and the amount of the persulfate is 200 to 400 parts by weight; The polybasic organic acid solution is the organic acid filtrate obtained after the filtration; The temperature of the hydrothermal reaction is 220-240°C.

2. The biomass-inorganic nanoparticle composite carbon sphere according to claim 1, characterized in that: The biomass powder is one or more of jute powder, peanut shell powder, fir bark powder, pine cone powder, bamboo shoot shell powder, coconut shell powder, soybean pod powder, sunflower seed shell powder, sunflower stem powder, rice straw powder, rice husk powder, corn straw powder and sisal powder.

3. The biomass-inorganic nanoparticle composite carbon sphere according to claim 1, characterized in that: The persulfate is one or more of ammonium persulfate, potassium persulfate and sodium persulfate.

4. A method for preparing the biomass-inorganic nanoparticle composite carbon spheres according to any one of claims 1 to 3, comprising the following steps: a) heating the inorganic nanoparticles and the polybasic organic acid in an organic solvent to react, and filtering to obtain polybasic organic acid-etched nanoparticles and an organic acid filtrate, respectively; b) subjecting the multi-organic acid corrosive nanoparticles, biomass powder and persulfate to a hydrothermal reaction under microwave assistance; after the reaction is completed, washing and drying the reaction product to obtain a dried material; c) calcining the dried material in the absence of oxygen to obtain a pyrolysis material; d) mixing the pyrolysis material with the organic acid filtrate and subjecting them to ultrasonic reaction; after the reaction is completed, washing, drying and grinding the reaction product to obtain biomass-inorganic nanoparticle composite carbon spheres.

5. The preparation method according to claim 4, characterized in that In step a), the heating reaction temperature is 50-70° C. and the heating reaction time is 1-3 hours; In step b), the microwave power of the microwave-assisted method is 800-1200 W; the hydrothermal reaction time is 12-24 h; In step c), the temperature of the oxygen-free calcination is 450-550° C. and the time of the oxygen-free calcination is 60-100 minutes; In step d), the ultrasonic frequency of the ultrasonic reaction is 40-60 kHz; the temperature of the ultrasonic reaction is 60-80° C.; and the time of the ultrasonic reaction is 20-40 minutes.

6. A heat-resistant antistatic composite material, prepared by melt blending raw materials comprising biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant, and a chain extender; The biomass-inorganic nanoparticle composite carbon sphere is the biomass-inorganic nanoparticle composite carbon sphere according to any one of claims 1 to 3 or the biomass-inorganic nanoparticle composite carbon sphere prepared by the preparation method according to any one of claims 4 to 5.

7. A method for preparing the heat-resistant antistatic composite material according to claim 6, comprising the following steps: Biomass-inorganic nanoparticle composite carbon spheres, polylactic acid, polybutylene adipate-terephthalate, an organic nucleating agent, a dispersant and a chain extender are melt-blended to obtain a heat-resistant antistatic composite material.

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