A multi-layer natural product-modified ultrafine hydrotalcite composite powder, its preparation method and application

Abstract

The present invention belongs to the technical field of functional materials, and discloses a multi-layer natural product-modified ultrafine hydrotalcite composite powder and its preparation method and application. The preparation method of the multi-layer natural product-modified ultrafine hydrotalcite composite powder includes the following steps: mixing caffeic acid, inorganic salt and solvent to obtain solution 1; mixing hydrotalcite and solvent to obtain dispersion liquid 2; dropping dispersion liquid 2 into solution 1 for reaction to obtain caffeic acid-modified hydrotalcite powder CA-UHM; mixing phenylboronic acid derivative, inorganic salt and solvent to obtain solution 3; mixing caffeic acid-modified hydrotalcite powder CA-UHM and solvent to obtain dispersion liquid 4; dropping dispersion liquid 4 into solution 3 for reaction to obtain a multi-layer natural product-modified ultrafine hydrotalcite composite powder 4-TA-CA-UHM. Caffeic acid and phenylboronic acid derivative are combined with hydrotalcite, simultaneously realizing the synergistic flame retardant effect of the condensed phase and the gas phase, and the comprehensive flame retardant and smoke suppression effects are remarkable.

Description

Technical Field

[0001] The present invention relates to the technical field of functional material applications, and in particular to a multi-layer natural product-modified ultrafine hydromagnesite composite powder, a preparation method thereof, and applications thereof. Background Art

[0002] Floor drains are essential components of interior design. In various environments, they are typically placed at a slope of 10 to 30 degrees to flush feces. They are typically made of hydrophobic materials to prevent feces from settling on the surface, reducing efficiency, and to prevent feces and other excreta from accumulating in the narrow slits of the drain, leading to bacterial growth. For this reason, polyolefin composites with low surface polarity are often used as floor drain materials. However, the overall performance of such composites needs to be improved, particularly in terms of flame retardancy, antibacterial properties, and retention of basic mechanical properties. Among the many types of inorganic powders, hydromagnesite mineral powder, a typical hydrated basic magnesium carbonate, is widely found in nature. It not only serves as a functional filler, providing reinforcement, but also exhibits flame retardancy and smoke suppression properties. However, several issues currently hinder its large-scale, high-value application, such as high surface polarity, which makes it susceptible to moisture absorption; high oil absorption, which makes it difficult to process; and increased surface area after crushing, which makes it prone to agglomeration.

[0003] Therefore, improving the application value of hydromagnesite ore is an urgent problem that needs to be solved. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-layer natural product modified ultrafine hydromagnesite composite powder and its preparation method and application, so as to solve the technical problems that hydromagnesite ore powder has high surface polarity, is easy to agglomerate and is not conducive to processing.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing a multilayer natural product-modified ultrafine hydromagnesite composite powder, comprising the following steps:

[0007] (1) mixing caffeic acid, an inorganic salt, and a solvent to obtain a solution 1;

[0008] (2) mixing hydromagnesite and a solvent to obtain a dispersion 2;

[0009] (3) adding dispersion 2 dropwise to solution 1 to react and obtain caffeic acid-modified hydromagnesite powder CA-UHM;

[0010] (4) mixing a phenylboronic acid derivative, an inorganic salt, and a solvent to obtain a solution 3;

[0011] (5) mixing the caffeic acid-modified hydromagnesite powder CA-UHM and a solvent to obtain dispersion 4;

[0012] (6) adding the dispersion 4 dropwise to the solution 3 to react and obtain a multilayer natural product modified ultrafine hydromagnesite composite powder 4-TA-CA-UHM;

[0013] There is no order restriction between steps (1) and (2);

[0014] There is no order restriction between steps (4) and (5).

[0015] Preferably, in the above-mentioned method for preparing a multilayer natural product-modified ultrafine hydromagnesite composite powder, the solvent in step (1) is ethanol, methanol, n-butanol, isopropanol, ethylene glycol, neopentyl alcohol, propanol, N,N-dimethylformamide or dimethyl sulfoxide;

[0016] The inorganic salt in step (1) is sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, calcium carbonate, magnesium hydroxide or calcium acetate.

[0017] Preferably, in the above-mentioned method for preparing a multi-layer natural product modified ultrafine hydromagnesite composite powder, the molar ratio of caffeic acid to inorganic salt in step (1) is 1:1-200;

[0018] The concentration of caffeic acid in the solution 1 in step (1) is 0.6 to 25 mol / L.

[0019] Preferably, in the above-mentioned method for preparing a multilayer natural product-modified ultrafine hydromagnesite composite powder, the solvent in step (2) is ethanol, methanol, ethylene glycol, water, propanol, n-butanol, isopropanol, neopentyl alcohol or isopropanol;

[0020] The molar concentration of hydromagnesite in the dispersion 2 in step (2) is 1 to 15 mol / L;

[0021] In step (3), the molar ratio of caffeic acid in solution 1 to hydromagnesite in dispersion 2 is 0.6 to 30:1;

[0022] The reaction temperature in step (3) is 20-80° C., and the reaction time is 0.5-72 h.

[0023] Preferably, in the above-mentioned method for preparing a multi-layer natural product modified ultrafine hydromagnesite composite powder, the phenylboronic acid derivative in step (4) is p-methylphenylboronic acid;

[0024] The solvents in step (4) and step (5) are independently N,N-dimethylformamide, dimethyl sulfoxide, acetonitrile, tetrahydrofuran or ethyl acetate;

[0025] The inorganic salt described in step (4) is sodium carbonate, potassium carbonate, cesium carbonate or sodium bicarbonate.

[0026] Preferably, in the above method for preparing a multi-layer natural product-modified ultrafine hydromagnesite composite powder, the molar ratio of the phenylboronic acid derivative to the inorganic salt in step (4) is 1:1 to 100;

[0027] The concentration of the phenylboronic acid derivative in solution 3 in step (4) is 1 to 20 mol / L.

[0028] Preferably, in the above method for preparing a multi-layer natural product-modified ultrafine hydromagnesite composite powder, the concentration of the caffeic acid-modified hydromagnesite powder CA-UHM in dispersion liquid 4 in step (5) is 1 to 10 mol / L;

[0029] The molar ratio of the phenylboronic acid derivative in solution 3 to the caffeic acid-modified hydromagnesite powder CA-UHM in dispersion liquid 4 in step (6) is 1 to 35:1;

[0030] The temperature of the reaction in step (6) is 20 to 100 °C, and the reaction time is 1 to 48 h.

[0031] The present invention also provides a multi-layer natural product-modified ultrafine hydromagnesite composite powder prepared by the method for preparing a multi-layer natural product-modified ultrafine hydromagnesite composite powder.

[0032] The present invention also provides an application of a multi-layer natural product-modified ultrafine hydromagnesite composite powder in a floor drain masterbatch.

[0033] Preferably, in the above application, the floor drain masterbatch comprises a polyolefin elastomer alloy material;

[0034] The polyolefin elastomer alloy material comprises the following components by weight:

[0035] 5 to 15 parts of POE, 5 to 30 parts of HDPE, 1 to 15 parts of EVA, 5 to 20 parts of 4-TA-CA-UHM, and 0.2 to 0.5 parts of an auxiliary agent.

[0036] In the multi-layer natural product-modified ultrafine hydromagnesite composite powder of the present invention, it is achieved through two-step reactions. The first step is that the natural product caffeic acid (3-(3,4-dihydroxyphenyl)-2-acrylic acid) modifies hydromagnesite to obtain CA-UHM, and the second step is that the obtained CA-UHM is modified by another natural derivative p-tolylboronic acid to obtain the ultrafine hydromagnesite composite powder 4-TA-CA-UHM; among them, caffeic acid is an extract derived from plants (such as Artemisia capillaris, Cynara scolymus, Lonicera japonica, etc.), and its structural formula is p-Tolylboronic acid is also a derivative of a natural product, and its structural formula is

[0037] When the molar ratio of surface caffeic acid to hydromagnesite powder is lower than 0.6:1, the caffeic acid content is too low, resulting in a large number of polar groups remaining on the surface of the hydromagnesite powder, which is not conducive to the subsequent further modification of phenylboronic acid derivatives. The overall modification effect is greatly reduced, which is not conducive to the improvement of the comprehensive performance of the composite powder. On the contrary, when the molar ratio of caffeic acid to hydromagnesite powder is higher than 30:1, the concentration of caffeic acid is too high, forming a more complex multi-layer coating on the surface, and may even wrap multiple hydromagnesite together, increasing the particle size of CA-UHM, and also affecting its further modification effect. In addition, the inorganic salt plays the role of dehydration and providing an alkaline environment.

[0038] It can be seen from the above technical solutions that compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The multi-layer natural product modified ultrafine hydromagnesite composite powder of the present invention is prepared by two-step modification, and its particle size is 1 to 4 μm. The internal hydromagnesite has good flame retardant and smoke suppression properties, and the caffeic acid on the surface has a multi-conjugated structure, which can promote the formation of a carbon layer to a certain extent. The outermost layer of phenylboric acid derivatives can not only further improve the modification effect, but also provide boron elements to enhance the flame retardant effect, and can also provide a certain aromatic ring to promote carbonization; caffeic acid, phenylboric acid derivatives and the internal hydromagnesite are combined with each other to achieve a condensed phase and gas phase synergistic flame retardant effect at the same time. During the pyrolysis process, the condensed phase carbon layer can prevent the transfer of heat flow, air flow and mass flow, and the carbon dioxide and water vapor released in the gas phase can dilute the combustion and degradation fragments, and the comprehensive flame retardant and smoke suppression effects are significant.

[0040] (2) Caffeic acid is extracted from natural plants and is widely found in plants such as artichoke and Artemisia capillaris. It is a renewable natural material. Phenylboric acid derivatives are also derived from plant extracts. They are widely available and inexpensive. They can be combined with caffeic acid to form a relatively dense multi-layer modified layer and placed on the outside of hydromagnesite. Hydromagnesite powder also comes from natural hydromagnesite mines, which is in line with the current low-carbon, environmentally friendly and sustainable material design concept.

[0041] (3) The preparation process of the hydromagnesite composite powder containing multi-layer natural product modification prepared by the present invention is simple and easy, the process is green and environmentally friendly, the energy consumption is low, the dependence on equipment is low, and the required reagents are abundant in source, without highly toxic solvents and components. The overall cost is controllable, the cost performance is high, the yield is high, it is suitable for large-scale industrial production, has great application potential, and has comprehensive advantages in flame retardancy and smoke suppression. The product is white or light grayish white, and is not easy to dye the polymer alloy, which is conducive to subsequent coloring.

[0042] (4) The multi-layer natural product-modified ultra-fine hydromagnesite composite powder (4-TA-CA-UHM) provided by the present invention can not only endow the floor drain masterbatch with certain reinforcing functions, but also endow the floor drain masterbatch with good flame retardant properties. In addition, it can also provide good smoke suppression and charring effects. Description of the Drawings

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art.

[0044] Figure 1 It is a schematic structural diagram of 4-TA-CA-UHM in Example 1;

[0045] Figure 2 It is a particle size distribution diagram of 4-TA-CA-UHM in Example 1;

[0046] Figure 3 It is a SEM diagram of 4-TA-CA-UHM in Example 1;

[0047] Figure 4 It is a process flow chart of the present invention. Detailed Embodiments

[0048] The present invention provides a preparation method of a multi-layer natural product-modified ultra-fine hydromagnesite composite powder, comprising the following steps:

[0049] (1) Mix caffeic acid, inorganic salt and solvent to obtain Solution 1;

[0050] (2) Mix hydromagnesite and solvent to obtain Dispersion 2;

[0051] (3) Drop Dispersion 2 into Solution 1 and react to obtain caffeic acid-modified hydromagnesite powder CA-UHM;

[0052] (4) Mix phenylboronic acid derivative, inorganic salt and solvent to obtain Solution 3;

[0053] (5) Mix caffeic acid-modified hydromagnesite powder CA-UHM and solvent to obtain Dispersion 4;

[0054] (6) Drop Dispersion 4 into Solution 3 and react to obtain a multi-layer natural product-modified ultra-fine hydromagnesite composite powder 4-TA-CA-UHM;

[0055] There is no order limit between steps (1) and (2);

[0056] There is no order limit between steps (4) and (5).

[0057] In the present invention, the solvent in step (1) is preferably ethanol, methanol, n-butanol, isopropanol, ethylene glycol, neopentyl alcohol, propanol, N,N-dimethylformamide or dimethyl sulfoxide, more preferably ethanol, methanol, n-butanol, isopropanol, ethylene glycol or neopentyl alcohol, more preferably ethanol, methanol or n-butanol.

[0058] In the present invention, the inorganic salt in step (1) is preferably sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, calcium carbonate, magnesium hydroxide or calcium acetate, more preferably sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate or calcium carbonate, more preferably sodium carbonate, potassium carbonate or cesium carbonate.

[0059] In the present invention, the molar ratio of caffeic acid to inorganic salt in step (1) is preferably 1:1-200, more preferably 1:10-180, and even more preferably 1:55-100.

[0060] In the present invention, the concentration of caffeic acid in the solution 1 in step (1) is preferably 0.6 to 25 mol / L, more preferably 5 to 20 mol / L, and even more preferably 8 to 15 mol / L.

[0061] In the present invention, the mixing method in step (1) is preferably stirring; the stirring time is preferably 1 to 36 hours, more preferably 5 to 32 hours, and more preferably 12 to 24 hours; the stirring rate is preferably 100 to 1200 rpm, more preferably 500 to 1000 rpm, and more preferably 800 to 900 rpm; the stirring temperature is preferably 25 to 60°C, more preferably 30 to 50°C, and more preferably 35 to 42°C.

[0062] In the present invention, the median particle size of the hydromagnesite in step (2) is preferably 0.6 to 3.6 μm, more preferably 0.8 to 3 μm, and even more preferably 1.4 to 2.5 μm.

[0063] In the present invention, the solvent in step (2) is preferably ethanol, methanol, ethylene glycol, water, propanol, n-butanol, isopropanol, neopentyl alcohol or isopropanol, more preferably ethanol, methanol, ethylene glycol, water, propanol or n-butanol, more preferably ethanol, methanol, ethylene glycol or propanol.

[0064] In the present invention, the molar concentration of hydromagnesite in the dispersion 2 in step (2) is preferably 1 to 15 mol / L, more preferably 3 to 12 mol / L, and even more preferably 5 to 8 mol / L.

[0065] In the present invention, the mixing time in step (2) is preferably 1 to 36 h, more preferably 5 to 32 h, and even more preferably 12 to 24 h; the mixing rotation speed is preferably 100 to 1000 rpm, more preferably 300 to 850 rpm, and even more preferably 500 to 600 rpm; the mixing temperature is preferably 20 to 50 °C, more preferably 25 to 45 °C, and even more preferably 30 to 40 °C.

[0066] In the present invention, the molar ratio of caffeic acid to hydromagnesite in the dispersion liquid 2 in solution 1 in step (3) is preferably 0.6 to 30:1, more preferably 3.5 to 22:1, and even more preferably 8 to 15:1.

[0067] In the present invention, the dropping rate in step (3) is preferably 1 to 10 drops / 6 s, more preferably 2 to 8 drops / 6 s, and even more preferably 5 to 7 drops / 6 s.

[0068] In the present invention, the specific process of the reaction in step (3): stirring for the reaction; the reaction temperature is preferably 20 to 80 °C, more preferably 35 to 70 °C, and even more preferably 55 to 60 °C; the reaction time is preferably 0.5 to 72 h, more preferably 3 to 60 h, and even more preferably 12 to 36 h; the stirring rate is preferably 100 to 1200 rpm, more preferably 500 to 1000 rpm, and even more preferably 600 to 800 rpm.

[0069] In the present invention, after the reaction in step (3), it further includes: centrifugal washing and auxiliary heat drying;

[0070] The centrifugal rate is preferably 1000 to 10000 rpm, more preferably 2000 to 8000 rpm, and even more preferably 4000 to 6000 rpm; the centrifugal time is preferably 5 to 50 min, more preferably 10 to 45 min, and even more preferably 20 to 30 min; the drying time is preferably 1 to 36 h, more preferably 5 to 30 h, and even more preferably 12 to 24 h; the temperature is preferably 60 to 100 °C, more preferably 65 to 90 °C, and even more preferably 70 to 90 °C.

[0071] In the present invention, the phenylboronic acid derivative in step (4) is preferably p-tolylboronic acid.

[0072] In the present invention, the solvents in steps (4) and (5) are independently preferably N,N-dimethylformamide, dimethyl sulfoxide, acetonitrile, tetrahydrofuran or ethyl acetate, more preferably N,N-dimethylformamide, dimethyl sulfoxide or acetonitrile, and even more preferably N,N-dimethylformamide or dimethyl sulfoxide.

[0073] In the present invention, the inorganic salt in step (4) is preferably sodium carbonate, potassium carbonate, cesium carbonate or sodium bicarbonate, more preferably sodium carbonate, potassium carbonate or cesium carbonate, and more preferably sodium carbonate or potassium carbonate.

[0074] In the present invention, the molar ratio of the phenylboronic acid derivative to the inorganic salt in step (4) is preferably 1:1-100, more preferably 1:5-85, and even more preferably 1:25-60.

[0075] In the present invention, the concentration of the phenylboronic acid derivative in the solution 3 in step (4) is preferably 1 to 20 mol / L, more preferably 3 to 18 mol / L, and even more preferably 5 to 12 mol / L.

[0076] In the present invention, the concentration of the caffeic acid-modified hydromagnesite powder CA-UHM in the dispersion 4 in step (5) is preferably 1 to 10 mol / L, more preferably 2 to 8 mol / L, and even more preferably 5 to 7 mol / L.

[0077] In the present invention, the mixing temperature in step (5) is preferably 20-60°C, more preferably 30-50°C, more preferably 35-40°C; the mixing time is preferably 1-48h, more preferably 10-36h, more preferably 12-24h; the mixing speed is preferably 100-1200rpm, more preferably 200-1000rpm, more preferably 500-800rpm.

[0078] In the present invention, the molar ratio of the phenylboronic acid derivative in the solution 3 in step (6) to the caffeic acid-modified hydromagnesite powder CA-UHM in the dispersion 4 is preferably 1 to 35:1, more preferably 5 to 28:1, and even more preferably 10 to 22:1.

[0079] In the present invention, the dripping rate in step (6) is preferably 1 to 10 drops / 4 s, more preferably 2 to 8 drops / 6 s, and even more preferably 5 to 7 drops / 6 s.

[0080] In the present invention, the specific process of the reaction in step (6) is: stirring to react; the reaction temperature is preferably 20-100°C, more preferably 40-80°C, more preferably 55-65°C; the reaction time is preferably 1-48h, more preferably 8-40h, more preferably 12-36h; the stirring rate is preferably 100-1500rpm, more preferably 300-1200rpm, more preferably 500-800rpm.

[0081] In the present invention, after the reaction of step (6) is completed, the method further comprises: dialyzing, centrifuging and washing, and freeze-drying the obtained product in sequence;

[0082] The specific process of the dialysis is as follows: the obtained product is placed in a dialysis bag; the material of the dialysis bag is cellulose ester, regenerated cellulose or polyvinylidene fluoride; the molecular weight cut-off of the dialysis bag is 800 to 30,000; the flattened width of the dialysis bag is 18 to 40 mm; the dialysis time is 1 to 96 hours;

[0083] The centrifugal washing conditions are as follows: a rotation speed of 800 to 8000 rpm, a time of 5 to 30 min, a detergent of ethanol, methanol, n-butanol, isopropanol, ethylene glycol, neopentyl alcohol or propanol, a mass volume ratio of the detergent to the product of 1 mL: 1 to 100 mg, and a number of times of 2 to 5 times;

[0084] The freeze-drying temperature is -50 to -5°C, and the time is 1 to 48 hours.

[0085] In the present invention, the median particle size of the ultrafine hydromagnesite composite powder 4-TA-CA-UHM in step (6) is 0.8 to 4 μm.

[0086] The present invention also provides a method for preparing a multi-layer natural product modified ultrafine hydromagnesia composite powder, and the multi-layer natural product modified ultrafine hydromagnesia composite powder is prepared.

[0087] The present invention also provides an application of multi-layer natural product modified ultrafine hydromagnesia composite powder in floor drain masterbatch.

[0088] In the present invention, the floor drain masterbatch comprises a polyolefin elastomer alloy material;

[0089] The polyolefin elastomer alloy material comprises the following components in parts by weight:

[0090] POE 5-15 parts, HDPE 5-30 parts, EVA 1-15 parts, 4-TA-CA-UHM 5-20 parts, additives 0.2-0.5 parts.

[0091] In the present invention, in the polyolefin elastomer alloy material, the weight portion of POE is preferably 5 to 15 parts, more preferably 8 to 12 parts, and even more preferably 9 to 10 parts.

[0092] In the present invention, in the polyolefin elastomer alloy material, the weight proportion of HDPE is preferably 5 to 30 parts, more preferably 8 to 25 parts, and even more preferably 12 to 20 parts.

[0093] In the present invention, the weight proportion of EVA in the polyolefin elastomer alloy material is preferably 1 to 15 parts, more preferably 3 to 12 parts, and even more preferably 7 to 10 parts.

[0094] In the present invention, in the polyolefin elastomer alloy material, the weight parts of 4-TA-CA-UHM are preferably 5 to 20 parts, more preferably 7 to 18 parts, and still more preferably 12 to 15 parts.

[0095] In the present invention, in the polyolefin elastomer alloy material, the weight parts of the additive are preferably 0.2 to 0.5 part, more preferably 0.3 to 0.4 part, and still more preferably 0.35 to 0.38 part.

[0096] In the present invention, the relative density of the POE is preferably 0.8 to 0.9 g / cm 3 , more preferably 0.82 to 0.88 g / cm 3 , still more preferably 0.84 to 0.85 g / cm 3 ;

[0097] The melting temperature of the POE is preferably 180 to 210 °C, more preferably 185 to 200 °C, and still more preferably 190 to 195 °C;

[0098] The hardness of the POE is preferably 52 to 90 A, more preferably 60 to 85 A, and still more preferably 70 to 80 A.

[0099] In the present invention, the POE is preferably LC170, LC175, LC565, LC670, POE6102, POE0201, POE0203, POE5101, POE8210, POE7447, POE7457, POE7467, POE8003, POE8100, POE8137, POE8150, POE8180, POE8200, POE8400, POE8401, POE8402, POE8407, POE8411, POE8440, POE8450, POE8452, POE8457, POE8480, POE8540, POE8842, C0750D, C5070D, C1070D, C1080, One of C3080, DF605, DF610, DF640, DF740, DF840, TA610, TA640, TA710, DF110, DF810, DF840, DF940, 1100, 2120, 2320, 2330, 3000, EXACT3402, EXACT0203, EXACT5101, EXACT3128, EXACT4011, EXACT4006, EXACT5181, EXACT5171, Dow 2000, Dow 2300, Dow 2400, Dow 3200, Dow 4000, SK8605L, SK861L, SK871L, SK875, SK883, and SK891, and more preferably POE7467.

[0100] In the present invention, the HDPE is preferably one of 5301AA, 5000S, 2200J, 2908, 5070, 5010, 5306J, MH602, CH2802, 7000F, 5306J, M5018L, 5018, 53EA010, 9001, HM5000 / 8800, F600, E308, TR144, 7000F, 5502, 4820, 952, 6888, and 5502, and more preferably 5070.

[0101] In the present invention, the EVA is preferably 2803A, 2802A, 4030AC, 1850A, 2830A, 1880A, 7240, UL04533CC, UL05540CC, HM728, HM2528, HM150, ES440, EF443, 612, 9F2, 4F2, 7350M, 12J4, 18J6, NU3050, NU3550, NU3770 , NU3210, NU3758, NU3760, NU3808, NU3190, 7340M, 7360M, 7670M, 150, 460, 1250M, KA-31, TX-9S, M8850, M8010, M8600, M8080, 2020, 2181, 28-420, 28-150, 18-500, 28-800, more preferably 2803A.

[0102] In the present invention, the auxiliary agent includes an antioxidant, and the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1.

[0103] In the present invention, the method for preparing the polyolefin elastomer alloy material comprises the following steps:

[0104] Weigh each component according to the above formula, add POE and HDPE, then add EVA, and then add 4-TA-CA-UHM and additives. After mixing evenly, extrude and granulate at 170-210°C, and then dry at 100°C after granulation.

[0105] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all 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.

[0106] Example 1

[0107] A method for preparing multi-layer natural product modified ultrafine hydromagnesite composite powder comprises the following steps:

[0108] (1) 901 mg of caffeic acid was dissolved in N,N-dimethylformamide, and then 25.2 g of sodium bicarbonate was added. The mixture was stirred at 800 rpm at 50°C for 12 h to obtain solution 1, in which the concentration of caffeic acid was 5 mol / L.

[0109] (2) 730.6 mg of hydromagnesite powder (D 501.8 μm) was mixed with methanol and dispersed at 40° C. and 600 rpm for 12 h to obtain dispersion 2, wherein the concentration of hydromagnesite powder was 2 mol / L;

[0110] (3) Dispersion 2 was added dropwise to solution 1 (dropping rate: 5 drops / 6s), stirred at 900 rpm at 60°C for 36 h, and centrifuged at 6000 rpm for 25 min after the reaction, and then dried in a vacuum oven at 80°C for 12 h to obtain caffeic acid-modified hydromagnesite powder CA-UHM.

[0111] (4) 1.4 g of p-tolueneboronic acid was dissolved in N,N-dimethylformamide, and then 42 g of sodium bicarbonate was added to obtain solution 3, wherein the concentration of p-tolueneboronic acid was 10 mol / L;

[0112] (5) Caffeic acid-modified hydromagnesite powder CA-UHM was mixed with dimethyl sulfoxide and dispersed at 45°C and 300 rpm for 24 h to obtain dispersion 4, wherein the concentration of caffeic acid-modified hydromagnesite powder CA-UHM was 2 mol / L;

[0113] (6) Dispersion 4 was added to solution 3 at a rate of 5 drops / 4s. The molar ratio of p-tolueneboronic acid to CA-UHM was 5:1. The mixture was stirred at 60°C and 1200 rpm for 24 h. After the reaction, the obtained product was placed in a cellulose ester dialysis bag with a flattened width of 38 mm and a molecular weight cutoff of 800-30000 for 72 h. Then, the product was centrifuged and washed at 4000 rpm for 15 min. The detergent was ethanol, and the mass volume ratio of ethanol to product was 1 mL:50 mg. The above process was repeated 3 times. Finally, the product was dispersed in deionized water and freeze-dried at -30°C for 24 h to obtain multi-layer natural product modified ultrafine hydromagnesia composite powder 4-TA-CA-UHM.

[0114] The preparation of floor drain masterbatch includes the following steps:

[0115] 10 parts of POE 7467 were mixed with 20 parts of HDPE 5070, and then 10 parts of EVA2803A were added, followed by 15 parts of the above-prepared 4-TA-CA-UHM and 0.4 parts of antioxidant (the mass ratio of antioxidants 1010 and 168 was 1:1). After mixing evenly, the mixture was extruded and granulated at 200°C, and then dried at 100°C to obtain a floor drain masterbatch.

[0116] The structural diagram of the ultrafine hydromagnesite composite powder 4-TA-CA-UHM prepared above is as follows Figure 1 As shown, a shell modified with caffeic acid and p-methylphenylboronic acid is attached to the surface of hydromagnesite.

[0117] The particle size distribution of the ultrafine hydromagnesia composite powder 4-TA-CA-UHM prepared above is as follows: Figure 2 As shown by Figure 2 It can be seen that the particle size distribution of 4-TA-CA-UHM is relatively uniform, showing a single peak, and concentrated around 2.0 μm.

[0118] The SEM image of the ultrafine hydromagnesite composite powder 4-TA-CA-UHM prepared above is as follows: Figure 3 As shown by Figure 3 It can be seen that there is a relatively dense coating layer on the surface of the powder, which is relatively evenly dispersed on the surface of the hydromagnesite particles and is relatively continuous as a whole, indicating that the modification effect is good.

[0119] Example 2

[0120] A method for preparing multi-layer natural product modified ultrafine hydromagnesite composite powder comprises the following steps:

[0121] (1) 108.1 mg of caffeic acid was dissolved in N,N-dimethylformamide, and then 82.9 mg of potassium carbonate was added. The mixture was stirred at 100 rpm at 25°C for 36 h to obtain solution 1, in which the concentration of caffeic acid was 0.6 mol / L.

[0122] (2) 365.3 mg of hydromagnesite powder (D 50 1.8 μm) was mixed with methanol and dispersed at 20° C. and 100 rpm for 36 h to obtain dispersion 2, wherein the concentration of hydromagnesite powder was 1 mol / L;

[0123] (3) Dispersion 2 was added dropwise to solution 1 (dropping rate: 1 drop / 6 s), stirred at 100 rpm at 20 °C for 72 h, and centrifuged at 1000 rpm for 50 min after the reaction, and then dried in a vacuum oven at 60 °C for 36 h to obtain caffeic acid-modified hydromagnesite powder CA-UHM.

[0124] (4) 135.9 mg of p-tolueneboronic acid was dissolved in N,N-dimethylformamide, and then 138.2 mg of potassium carbonate was added to obtain solution 3, wherein the concentration of p-tolueneboronic acid was 1 mol / L;

[0125] (5) Caffeic acid-modified hydromagnesite powder CA-UHM was mixed with dimethyl sulfoxide and dispersed at 20°C and 100 rpm for 48 h to obtain dispersion 4, wherein the concentration of caffeic acid-modified hydromagnesite powder CA-UHM was 1 mol / L;

[0126] (6) Dispersion 4 was added to solution 3 at a rate of 1 drop / 4s. The molar ratio of p-tolueneboronic acid to CA-UHM was 1:1. The mixture was stirred at 100 rpm at 20°C for 48 h. After the reaction, the obtained product was placed in a cellulose ester dialysis bag with a flattened width of 18 mm and a molecular weight cutoff of 800-30,000 for 1 h. The product was then centrifuged and washed at 800 rpm for 30 min. The detergent was isopropanol, and the mass volume ratio of isopropanol to product was 1 mL:1 mg. The above process was repeated twice. Finally, the product was dispersed in deionized water and freeze-dried at -5°C for 48 h to obtain multi-layer natural product modified ultrafine hydromagnesia composite powder 4-TA-CA-UHM.

[0127] The preparation of floor drain masterbatch includes the following steps:

[0128] Mix 5 parts of POE 7467 with 5 parts of HDPE 5070, then add 15 parts of EVA2803A, then add 5 parts of the above-prepared 4-TA-CA-UHM and 0.2 parts of antioxidant (the mass ratio of antioxidants 1010 and 168 is 1:1), mix well, extrude and granulate at 200°C, then dry at 100°C, and finally obtain floor drain masterbatch after injection molding.

[0129] Example 3

[0130] A method for preparing multi-layer natural product modified ultrafine hydromagnesite composite powder comprises the following steps:

[0131] (1) 27.1 g of caffeic acid was dissolved in N,N-dimethylformamide, and then 3180 g of sodium carbonate was added. The mixture was stirred at 1200 rpm at 60°C for 1 h to obtain solution 1, in which the concentration of caffeic acid was 25 mol / L.

[0132] (2) 1.8g hydromagnesite powder (D 50 1.8 μm) was mixed with methanol and dispersed at 50° C. and 1000 rpm for 1 h to obtain dispersion 2, wherein the concentration of hydromagnesite powder was 15 mol / L;

[0133] (3) Dispersion 2 was added dropwise to solution 1 (drop rate: 10 drops / 6s), stirred at 80°C and 1200 rpm for 0.5 h, and after the reaction, centrifuged at 10000 rpm for 5 min, and then dried in a vacuum oven at 100°C for 1 h to obtain caffeic acid-modified hydromagnesite powder CA-UHM.

[0134] (4) 4.8 g of p-tolueneboronic acid was dissolved in N,N-dimethylformamide, and then 371 g of sodium carbonate was added to obtain solution 3, wherein the concentration of p-tolueneboronic acid was 20 mol / L;

[0135] (5) Mix the coffee acid-modified hydromagnesite powder CA-UHM with dimethyl sulfoxide, disperse it at 1200 rpm for 1 h at 60 °C to obtain dispersion liquid 4, wherein the concentration of the coffee acid-modified hydromagnesite powder CA-UHM is 10 mol / L;

[0136] (6) Drop dispersion liquid 4 into solution 3 at a dropping rate of 10 drops / 4 s. The molar ratio of p-tolylboronic acid to CA-UHM is 35:1. Stir and react at 1500 rpm at 100 °C for 1 h. After the reaction, place the obtained product in a cellulose ester dialysis bag with a flattened width of 40 mm and a molecular weight cut-off of 800 - 30000 for dialysis for 96 h, then centrifuge and wash at 8000 rpm for 5 min. The detergent is n-butanol, and the mass-volume ratio of n-butanol to the product is 1 mL:100 mg. Repeat the above process 5 times. Finally, disperse the product in deionized water and perform freeze-drying at -50 °C for 1 h to obtain the multi-layer natural product-modified ultrafine hydromagnesite composite powder 4-TA-CA-UHM.

[0137] The preparation of the floor drain masterbatch includes the following steps:

[0138] Mix 15 parts of POE 7467 with 30 parts of HDPE 5070, then add 1 part of EVA2803A, then add 20 parts of the obtained 4-TA-CA-UHM and 0.5 part of antioxidant (the mass ratio of antioxidant 1010 to 168 is 1:1). After mixing evenly, extrude and pelletize at 200 °C, then dry at 100 °C, and finally obtain the floor drain masterbatch after injection molding.

[0139] Comparative Example 1

[0140] A preparation method of a multi-layer natural product-modified ultrafine hydromagnesite composite powder is the same as that in Example 1, and the only difference is that the mass of coffee acid is 54.1 mg.

[0141] The preparation of the floor drain masterbatch includes the following steps:

[0142] Mix 10 parts of POE 7467 with 20 parts of HDPE 5070, then add 10 parts of EVA2803A, then add 15 parts of the obtained 4-TA-CA-UHM and 0.4 part of antioxidant (the mass ratio of antioxidant 1010 to 168 is 1:1). After mixing evenly, extrude and pelletize at 200 °C, and then dry at 100 °C to obtain the floor drain masterbatch.

[0143] Comparative Example 2

[0144] A preparation method of a multi-layer natural product-modified ultrafine hydromagnesite composite powder, which is the same as that in Example 1, and the only difference is that the mass of caffeic acid is 6.3 g.

[0145] The preparation of the floor drain masterbatch includes the following steps:

[0146] Mix 10 parts of POE 7467 with 20 parts of HDPE 5070, then add 10 parts of EVA2803A, then add 15 parts of the prepared 4-TA-CA-UHM and 0.4 parts of antioxidant (the mass ratio of antioxidant 1010 and 168 is 1:1), mix evenly and then extrude and pelletize at 200 °C, and then dry at 100 °C to obtain the floor drain masterbatch.

[0147] Comparative Example 3

[0148] The hydromagnesite is pulverized, air-selected and classified multiple times to obtain hydromagnesite powder (D 50 is 1.8 μm).

[0149] The preparation of the floor drain masterbatch includes the following steps:

[0150] Mix 10 parts of POE 7467 with 20 parts of HDPE 5070, then add 10 parts of EVA2803A, then add 15 parts of hydromagnesite powder and 0.4 parts of antioxidant (the mass ratio of antioxidant 1010 and 168 is 1:1), mix evenly and then extrude and pelletize at 200 °C, then dry at 100 °C, and finally obtain the floor drain masterbatch after injection molding.

[0151] Performance test

[0152] The specific surface area and oil absorption value of 4-TA-CA-UHM in Examples 1 to 3, Comparative Examples 1 to 2 and the hydromagnesite powder in Comparative Example 3 were tested, and the test results are shown in Table 1.

[0153] Specific surface area: Tested using a BET specific surface area analyzer;

[0154] Oil absorption value: Tested according to the DB / T5211.15-2014 standard.

[0155] Table 1 Test results of specific surface area and oil absorption value of 4-TA-CA-UHM in Examples 1 to 3, Comparative Examples 1 to 2 and hydromagnesite powder in Comparative Example 3

[0156]

[0157]

[0158] Comparing the tested data in Table 1, it can be seen that the specific surface area of the ultrafine hydromagnesite composite powder significantly increases after being modified by various natural products, and the oil absorption value significantly decreases. Especially when caffeic acid and natural hydromagnesite powder are within a suitable ratio range (0.6 - 30:1), the specific surface area and oil absorption value are greatly improved and decreased. In contrast (Comparative Examples 1 - 3), when caffeic acid, a natural product, and high-mesh hydromagnesite powder are not within the suitable range, that is, when the natural product caffeic acid is too high or too low, when it is too low, the surface modification effect is average, and it is difficult for subsequent phenylboronic acid derivatives to achieve effective modification, resulting in a poor overall surface modification effect on the powder; when the natural product caffeic acid is too high, excessive natural products may wrap multiple hydromagnesite particles together, also causing an increase in the particle size of the hydromagnesite powder, ultimately leading to a certain increase in the specific surface area of the composite powder and an average decrease in the oil absorption value. Thus, it can be seen that after adding the natural product caffeic acid, the specific surface area and oil absorption value of the overall powder can be effectively improved, and adding too much or too little will cause a decrease in the surface modification effect. The improvement of these properties has good effects on the adsorption amount of additives, cost control, and maintenance of mechanical properties during subsequent processing.

[0159] The floor drain masterbatches prepared in Examples 1 - 3 and Comparative Examples 1 - 3 were injection molded into specimens for performance testing, and the results are shown in Table 2.

[0160] Limiting oxygen index: The lowest oxygen concentration required for the test material to burn with a flame in a mixed O2 / N2 gas stream under the test conditions required by GB / T8924 - 2005;

[0161] Flame retardant grade: The flame retardant performance was tested with reference to GB / T 2408 - 2021, and the thickness of the specimen was 3.2 mm;

[0162] Residual carbon rate test: Measured in a nitrogen atmosphere at a heating rate of 10 °C / min, and the ratio of the residual carbon mass to the initial mass was measured at 600 °C;

[0163] Tensile strength: The tensile strength was tested with reference to the standard of GB / T 1040 - 2006, and the tensile speed was 200 mm / min.

[0164] Table 2 Performance test results of the floor drain masterbatches prepared in Examples 1 - 3 and Comparative Examples 1 - 3

[0165]

[0166]

[0167] As can be seen from the results presented in Table 2, with the addition of the multi-layer natural product-modified ultrafine hydrotalcite composite powder (4-TA-CA-UHM) to the polyolefin composite masterbatch, there is a significant increase in the limiting oxygen index, rising from 21.3% measured in Comparative Example 3 to 30.5% (Example 1). Even when the content of the surface natural product caffeic acid is too low or too high, there is still a certain degree of improvement in the limiting oxygen index. Therefore, the multi-layer natural product-modified ultrafine hydrotalcite composite powder has a relatively obvious promoting effect on improving the combustion performance of polyolefin floor drain masterbatch, providing better passive protection technology for the combustion that occurs during the use of the floor drain and better delaying the combustion process. In terms of the flame retardant rating, after adding an appropriate proportion of 4-TA-CA-UHM, the flame retardant rating of the polyolefin floor drain masterbatch can reach V-0, that is, it can achieve a better inhibitory flame retardant effect during vertical combustion. However, when the ratio of the natural product on the surface of the composite powder to the internal ultrafine hydrotalcite does not match, the flame retardant rating decreases, and the overall flame retardant efficiency decreases, which is not conducive to improving the flame retardant effect of the floor drain masterbatch. Particularly obvious is that when directly adding unmodified hydrotalcite powder, the polyolefin elastomer composite material even has no flame retardant rating. Moreover, by comparing the char residue rates of the above-mentioned examples and comparative examples at 600 °C, it is found that after adding an appropriate proportion of 4-TA-CA-UHM, the char residue rate of the polyolefin floor drain masterbatch at 600 °C increases significantly. In Comparative Example 3, it is only 26.7 wt%, while in the example, it reaches a maximum of 43.6 wt%. When the ratio of the surface natural product to the ultrafine hydrotalcite does not match, the char residue rate also decreases to a certain extent, indicating a decrease in the char-forming effect. At this time, the natural product and the ultrafine hydrotalcite cannot well exert the synergistic flame retardant effect. In terms of the tensile strength, when adding the ultrafine hydrotalcite composite powder modified with multiple natural products, the tensile strength of the polyolefin elastomer composite material increases significantly. This is because the modification of the natural product is beneficial to the better dispersion of the hydrotalcite powder in the polyolefin elastomer matrix. At the same time, the compatibility is also better. When encountering external tensile force, stress defects are not easily generated, which is beneficial to improving the mechanical properties of the composite material. When the proportion of the surface natural product caffeic acid in the composite powder is too high or too low, or even when no natural product modification is carried out (Comparative Examples 1-3), the tensile strength of the polyolefin floor drain composite material drops significantly, indicating that the unreasonable modification of the composite powder will greatly affect the mechanical properties of the final polymer composite material, making its mechanical properties poor when acting as a floor drain material and possibly inducing deformation or fracture. The above results show that the introduction of the natural product caffeic acid and phenylboric acid derivatives can improve the properties of hydrotalcite particle powder in terms of flame retardancy, thermal performance, and promoting char formation. Making full use of its low polarity and multi-conjugated structure can enable the hydrotalcite composite powder to have good dispersibility and char-forming ability in the polyolefin elastomer masterbatch, which has a good effect on improving its final flame retardant performance and mechanical properties.

[0168] The masterbatches prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were tested for their antibacterial effects. According to GB / T 31402-2015, their inhibitory effects on Escherichia coli and Staphylococcus aureus were detected after being placed at room temperature for 0, 3 months, and 6 months. The results are shown in Table 3.

[0169] Table 3 Antibacterial effects of the floor drain masterbatches prepared in Examples 1 to 3 and Comparative Examples 1 to 3

[0170]

[0171] As can be seen from the antibacterial results presented in Table 3, the introduction of the natural product caffeic acid can significantly improve the antibacterial performance of the floor drain masterbatch within 6 months of placement. This is because the natural product caffeic acid itself has good antibacterial and antiviral properties, which can effectively improve the antibacterial effect of the hydrotalcite composite powder, and thus improve the antibacterial performance of the floor drain masterbatch. When the content of the surface natural product caffeic acid is too low or too high, it cannot exert good antibacterial efficacy when added to the floor drain masterbatch, showing a certain downward trend as a whole. Especially when the natural product caffeic acid is too low (Comparative Example 1), its improvement of the antibacterial performance of the polyolefin floor drain masterbatch is very limited. Compared with the addition of unmodified hydrotalcite powder (Comparative Example 3), the improvement effect is not obvious. Based on the above test results, the introduction of the natural product caffeic acid and phenylboronic acid derivatives can effectively improve the surface properties of hydrotalcite and the comprehensive properties of the composite powder after successive modifications of ultrafine hydrotalcite. When added to the polymer matrix, it can effectively improve the tensile strength, flame retardancy grade, and limiting oxygen index of the polyolefin composite, and has a good promotion effect on the flame retardancy, mechanical properties, and antibacterial properties required for the floor drain masterbatch.

[0172] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A preparation method of a multi-layer natural product-modified ultrafine hydromagnesite composite powder, characterized in that, It includes the following steps: (1) Mix caffeic acid, inorganic salt and solvent to obtain Solution 1; (2) Mix hydromagnesite and solvent to obtain Dispersion 2; (3) Drop Dispersion 2 into Solution 1 for reaction to obtain caffeic acid-modified hydromagnesite powder CA-UHM; (4) Mix phenylboronic acid derivative, inorganic salt and solvent to obtain Solution 3; (5) Mix caffeic acid-modified hydromagnesite powder CA-UHM and solvent to obtain Dispersion 4; (6) Drop Dispersion 4 into Solution 3 for reaction to obtain multi-layer natural product-modified ultrafine hydromagnesite composite powder 4-TA-CA-UHM; In step (3), the molar ratio of caffeic acid in Solution 1 to hydromagnesite in Dispersion 2 is 0.6~30:1; There is no order restriction between steps (1) and (2); There is no order restriction between steps (4) and (5).

2. The preparation method of the ultrafine hydromagnesite composite powder modified by multilayer natural products according to claim 1, wherein, The solvent in step (1) is ethanol, methanol, n-butanol, isopropanol, ethylene glycol, neopentyl alcohol, propanol, N,N-dimethylformamide or dimethyl sulfoxide; The inorganic salt in step (1) is sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, calcium carbonate, magnesium hydroxide or calcium acetate.

3. The method for preparing the multi-layer natural product modified ultrafine hydromagnesite composite powder according to claim 1 or 2, characterized in that: In step (1), the molar ratio of caffeic acid to inorganic salt is 1:1~200; In step (1), the concentration of caffeic acid in Solution 1 is 0.6~25 mol / L.

4. The preparation method of the ultrafine hydromagnesite composite powder modified by a multi-layer natural product according to claim 3, characterized in that, The solvent in step (2) is ethanol, methanol, ethylene glycol, water, propanol, n-butanol, isopropanol, neopentyl alcohol or isopropanol; In step (2), the molar concentration of hydromagnesite in Dispersion 2 is 1~15 mol / L; In step (3), the reaction temperature is 20~80 °C and the reaction time is 0.5~72 h.

5. The preparation method of the ultrafine hydromagnesite composite powder modified by a multi-layer natural product according to claim 4, characterized in that, The phenylboronic acid derivative in step (4) is p-tolylboronic acid; The solvents in steps (4) and (5) are independently N,N-dimethylformamide, dimethyl sulfoxide, acetonitrile, tetrahydrofuran or ethyl acetate; The inorganic salt in step (4) is sodium carbonate, potassium carbonate, cesium carbonate or sodium bicarbonate.

6. The preparation method of the multi-layer natural product-modified ultrafine hydromagnesite composite powder according to claim 4 or 5, characterized in that, In step (4), the molar ratio of phenylboronic acid derivative to inorganic salt is 1:1~100; In step (4), the concentration of phenylboronic acid derivative in Solution 3 is 1~20 mol / L.

7. The method for preparing the multi-layer natural product modified ultrafine hydromagnesite composite powder according to claim 6, characterized in that: In step (5), the concentration of caffeic acid-modified hydromagnesite powder CA-UHM in Dispersion 4 is 1~10 mol / L; In step (6), the molar ratio of phenylboronic acid derivative in Solution 3 to caffeic acid-modified hydromagnesite powder CA-UHM in Dispersion 4 is 1~35:1; In step (6), the reaction temperature is 20~100 °C and the reaction time is 1~48 h.

8. The multi-layer natural product-modified ultrafine hydromagnesite composite powder prepared by the preparation method of the multi-layer natural product-modified ultrafine hydromagnesite composite powder according to any one of claims 1 to 7.

9. The application of the multi-layer natural product-modified ultrafine hydromagnesite composite powder according to claim 8 in a floor drain masterbatch.

10. The application according to claim 9, characterized in that, The floor drain masterbatch includes a polyolefin elastomer alloy material; The polyolefin elastomer alloy material includes the following components by weight: POE 5-15 parts, HDPE 5-30 parts, EVA 1-15 parts, 4-TA-CA-UHM 5-20 parts, additives 0.2-0.5 parts.

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