A reinforced PVC floor and preparation method thereof

Abstract

The present invention discloses a reinforced PVC floor and its preparation method. The PVC floor comprises the following raw materials by weight: 80-120 parts PVC powder, 10-30 parts plasticizer, 30-60 parts filler powder, 1-2 parts lubricant, 1-3 parts heat stabilizer, and 2-5 parts flame retardant; the filler powder is a mixture of molybdenum-doped lanthanum aluminate powder, calcium carbonate powder, and wood flour; and the flame retardant is a depolymerized lignin derivative. The reinforced PVC floor of the present invention has a rational formulation, resulting in excellent wear resistance. The combination of molybdenum-doped lanthanum aluminate powder and the depolymerized lignin derivative enhances the floor's flame retardancy. Furthermore, the reinforced PVC floor exhibits excellent corrosion resistance and strong aging resistance, meeting the requirements of long-term use.

Description

Technical Field

[0001] The present invention relates to the technical field of PVC flooring, in particular to a reinforced PVC flooring and a preparation method thereof. Background Art

[0002] PVC flooring is a flooring material made from polyvinyl chloride (PVC). It is wear-resistant, waterproof, non-slip, corrosion-resistant, and easy to clean, making it an environmentally friendly, practical, and economical flooring option. Therefore, it is widely used in various places such as homes, businesses, and offices. PVC flooring is produced by using polyvinyl chloride and its copolymer resins as the main raw materials, adding auxiliary materials such as fillers, plasticizers, stabilizers, and colorants. The materials are then coated onto a sheet-like continuous substrate or produced through calendering, extrusion, or other processes.

[0003] Some existing technologies have incorporated wear-resistant agents and waste materials into PVC flooring formulations to produce wear-resistant or environmentally friendly recyclable PVC flooring. For example, CN10935480A discloses a highly wear-resistant PVC floor film composed of the following components by weight: 100 parts high-K-value PVC powder, 40-50 parts plasticizer, 2-3 parts heat stabilizer, 1-3 parts fumed silica, 0.9-1.2 parts lubricant, 3-5 parts flame retardant, 0.7-1 part UV absorber, and 15-20 parts TPU. This PVC floor film exhibits enhanced tensile and tear strength, excellent wear resistance, and flame retardancy, as well as resistance to aging. CN11262537A discloses a waste wood reinforced recycled PVC foam floor and a preparation method thereof. A mixture of waste fir, maple and oak materials is ground into powder. Industrial waste PVC plastic and new semi-rigid PVC plastic are ground into powder. After uniform mixing, a foaming agent, a stabilizer, a coupling agent and a lubricant are added. The mixture is stirred at high temperature and extruded into uniform pellets through a three-screw extruder. The pellets are then heated and melted, and the melt is formed into a mold. The floor surface prepared by this method is not easily deformed and can reduce manufacturing costs.

[0004] It is necessary to improve the formula of PVC flooring, enhance the performance of PVC flooring and expand its use. Summary of the Invention

[0005] In order to solve the technical problems existing in the prior art, the present invention provides a reinforced PVC floor, comprising the following raw materials in parts by weight:

[0006] 80-120 parts of PVC powder, 10-30 parts of plasticizer, 30-60 parts of filler powder, 1-2 parts of lubricant, 1-3 parts of heat stabilizer, 2-5 parts of flame retardant;

[0007] The filler powder is made by mixing molybdenum-doped lanthanum aluminate powder, calcium carbonate powder and wood powder;

[0008] The flame retardant is a depolymerized lignin derivative.

[0009] Lignin contains a large number of aromatic structures, which give it excellent thermal stability and excellent charring properties. It is often used as the main carbon source for intumescent flame retardants. To further improve the flame retardancy, lignin can be grafted with flame retardant elements (such as nitrogen and phosphorus) to prepare lignin derivatives with better flame retardancy.

[0010] Furthermore, the preparation method of the depolymerized lignin derivative comprises the following steps, in parts by weight:

[0011] S1, mixing 5-10 parts of depolymerized lignin, 20-50 parts of water, and 0.2-1 part of triethylenetetramine with stirring for reaction, and collecting insoluble matter to obtain an intermediate product;

[0012] S2. Mix 5 to 10 parts of the intermediate product, 2 to 5 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 0.01 to 0.05 parts of tin tetrachloride, stir and react, and collect insoluble matter to obtain a depolymerized lignin derivative.

[0013] Furthermore, the stirring reaction in step S1 and step S2 is continued for 2 to 5 hours at a temperature of 50 to 90° C. and a stirring rate of 200 to 400 rpm.

[0014] Lanthanum aluminate, an ABO3 compound with a perovskite structure, exhibits low dielectric constant, low dielectric loss, good lattice matching, low thermal expansion coefficient, excellent chemical stability, wide band gap, large specific surface area, and excellent thermal stability. These properties make lanthanum aluminate potentially beneficial for enhancing the aging resistance of PVC flooring. Doping lanthanum aluminate with molybdenum is expected to further improve its performance.

[0015] Furthermore, the preparation method of the molybdenum-doped lanthanum aluminate powder includes:

[0016] A soluble molybdenum salt, a soluble lanthanum salt, a soluble aluminum salt, citric acid and water are mixed to obtain a mixed solution, which is stirred at a temperature of 60 to 90° C. and a stirring rate of 300 to 500 rpm to form a gel, and then the temperature is raised to 110 to 130° C., the solid is collected and calcined at 500 to 700° C. for 1 to 3 hours, and then ground to obtain molybdenum-doped lanthanum aluminate powder;

[0017] The molar ratio of soluble molybdenum salt, soluble lanthanum salt, soluble aluminum salt and citric acid is 0.1-0.3:0.7-0.9:1:2-2.5, and the concentration of total metal ions in the mixed solution is 0.05-0.1 mol / L.

[0018] Furthermore, the mass ratio of the molybdenum-doped lanthanum aluminate powder, calcium carbonate powder and wood powder is 2-5:5-10:20-45.

[0019] In the PVC flooring formula of the present invention, PVC is the matrix, and molybdenum-doped lanthanum aluminate powder, calcium carbonate powder, and wood powder are all filler particles. The matrix and filler will produce stress concentration. In theory, the larger the filler particle size, the more difficult it is to disperse in the system, and the higher the stress intensity. When the material is subjected to external force, the filler and the matrix interface are prone to detachment, forming holes. The larger the particle size, the larger the hole. Large holes will cause the material to break and have poor mechanical properties. When the particle size is small to a certain extent, the filler particles will agglomerate. The smaller the particle size, the more severe the agglomeration phenomenon, and the dispersibility becomes worse. In order to achieve better dispersion, more and better processing aids are needed, and more stringent and high-end requirements are placed on processing equipment, which undoubtedly increases the processing cost of PVC-based wood-plastic composite materials. Therefore, the particle size of molybdenum-doped lanthanum aluminate powder, calcium carbonate powder, and wood powder needs to be within an appropriate range, that is, not too large or too small.

[0020] Furthermore, the mesh size of the molybdenum-doped lanthanum aluminate powder, calcium carbonate powder and wood powder is 50 to 400 meshes.

[0021] Furthermore, the polymerization degree of the PVC powder is 500-2000.

[0022] Furthermore, the plasticizer is at least one of a citrate plasticizer, an epoxidized plasticizer, and a polyester plasticizer.

[0023] Furthermore, the lubricant is at least one of paraffin, stearic acid, monoglyceride, butyl stearate, stearyl alcohol, polyethylene wax, and oxidized polyethylene wax.

[0024] The present invention also provides a method for preparing the above-mentioned enhanced PVC floor, comprising the following steps:

[0025] PVC powder, plasticizer, filler powder, lubricant, heat stabilizer and flame retardant are dispersed and mixed to obtain expanded powder;

[0026] The expanded powder is extruded to obtain a rubber compound, which is then heated and melted and poured into a mold for solidification to obtain a reinforced PVC floor.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The reinforced PVC floor of the present invention has a reasonable formula, so that the PVC floor has good wear resistance. The combination of molybdenum-doped lanthanum aluminate powder and depolymerized lignin derivative improves the flame retardant performance of the floor. At the same time, the reinforced PVC floor has good corrosion resistance and strong aging resistance, which can meet the needs of long-term use. DETAILED DESCRIPTION

[0029] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to form one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed in the present invention.

[0030] Introduction to some of the raw materials used in the embodiments of the present invention:

[0031] PVC powder, model S700, average degree of polymerization 650-750, purchased from Sinopec Qilu Petrochemical Company;

[0032] Citrate plasticizer, butyryl tri-n-hexyl citrate, model BDCH, was purchased from Guangzhou Shanghe Chemical Technology Co., Ltd.;

[0033] Calcium carbonate powder, product number TSG01, mesh size 325, purchased from Shijiazhuang Xinsheng Mineral Products Co., Ltd.

[0034] Wood flour, item number MF-4056, mesh size 325, purchased from Lingshou County Ningbo Mineral Products Co., Ltd.

[0035] Polyethylene wax, model LP0020P, was purchased from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.;

[0036] XT-3 rare earth stabilizer, model XT-3, purchased from Jining Tangyi Chemical Co., Ltd.;

[0037] Depolymerized lignin, model LIG-Ⅰ, was purchased from Shandong Longli Biotechnology Co., Ltd.

[0038] Other raw materials not mentioned are common raw materials in this field and can be directly purchased from the market and will not be described in detail.

[0039] The following will be combined with specific embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] Example 1

[0041] A method for preparing a reinforced PVC floor comprises the following steps, calculated in parts by weight:

[0042] Step 1, weighing 100 parts of PVC powder, 20 parts of citrate plasticizer, 4 parts of molybdenum-doped lanthanum aluminate powder, 8 parts of calcium carbonate powder, 36 parts of wood flour, 1.5 parts of polyethylene wax, 2 parts of XT-3 rare earth stabilizer, and 5 parts of depolymerized lignin derivative;

[0043] Step 2: PVC powder, citrate plasticizer, molybdenum-doped lanthanum aluminate powder, calcium carbonate powder, wood flour, polyethylene wax, XT-3 rare earth stabilizer, and depolymerized lignin derivative are placed in a blender and stirred at 105° C. to obtain expanded powder;

[0044] Step 3: Pour the expanded powder into a three-screw extruder, set the barrel temperature of the extruder to 170°C in zone 1, 175°C in zone 2, 180°C in zone 3, and 182°C in the die head, the rotation speed to 200r / min, and the feeding rate to 400pph / r, so that the mixture is heated and plasticized in the extruder and extruded to obtain a rubber compound, heat the rubber compound to melt at 200°C, pour the melt into a mold, and demold after curing and molding to obtain a reinforced PVC floor.

[0045] The preparation method of molybdenum-doped lanthanum aluminate powder comprises the following steps: weighing sodium molybdate dihydrate, lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate, and citric acid in a molar ratio of 0.1:0.8:1:2.5; then mixing the sodium molybdate dihydrate, lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate, and citric acid with water; and stirring the mixture at 350 rpm for 20 minutes to obtain a mixed solution, wherein the total metal ion concentration in the mixed solution is 0.1 mol / L; forming a gel at a temperature of 80° C. and a stirring rate of 500 rpm; then heating the mixed solution to 120° C., collecting the solid, calcining it at 600° C. for 2 hours, and then grinding and sieving to obtain 300-mesh molybdenum-doped lanthanum aluminate powder;

[0046] The preparation method of depolymerized lignin derivatives is calculated by weight as follows:

[0047] S1. 10 parts of depolymerized lignin, 50 parts of water, and 1 part of triethylenetetramine were mixed and stirred at 200 rpm for 2 h. The insoluble matter was collected and washed with anhydrous ethanol and water three times each, and dried in a constant temperature oven at 80°C to obtain an intermediate product.

[0048] S2. 10 parts of the intermediate product, 5 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 0.01 parts of tin tetrachloride were mixed and stirred at 350 rpm for 5 hours, and the insoluble matter was collected and washed with anhydrous ethanol and water three times each, and dried in a constant temperature oven at 80°C to obtain a depolymerized lignin derivative.

[0049] Example 2

[0050] A method for preparing a reinforced PVC floor is basically the same as that of Example 1, except that: in the preparation method of molybdenum-doped lanthanum aluminate powder, sodium molybdate dihydrate, lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate, and citric acid are weighed in a molar ratio of 0.2:0.8:1:2.5.

[0051] Example 3

[0052] A method for preparing a reinforced PVC floor is basically the same as that of Example 1, except that: in the method for preparing molybdenum-doped lanthanum aluminate powder, sodium molybdate dihydrate, lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate, and citric acid are weighed in a molar ratio of 0.3:0.8:1:2.5.

[0053] Example 4

[0054] It is basically the same as Example 2, except that the mesh size of the molybdenum-doped lanthanum aluminate powder is 200 mesh.

[0055] Example 5

[0056] It is basically the same as Example 2, except that the mesh size of the molybdenum-doped lanthanum aluminate powder is 400 mesh.

[0057] Comparative Example

[0058] A method for preparing a reinforced PVC floor comprises the following steps, calculated in parts by weight:

[0059] Step 1, weighing 100 parts of PVC powder, 20 parts of citrate plasticizer, 4 parts of lanthanum aluminate powder, 8 parts of calcium carbonate powder, 36 parts of wood flour, 1.5 parts of polyethylene wax, 2 parts of XT-3 rare earth stabilizer, and 5 parts of depolymerized lignin derivative;

[0060] Step 2: PVC powder, citrate plasticizer, lanthanum aluminate powder, calcium carbonate powder, wood flour, polyethylene wax, XT-3 rare earth stabilizer, and depolymerized lignin derivative are placed in a blender and stirred at 105° C. to obtain expanded powder;

[0061] Step 3: Pour the expanded powder into a three-screw extruder, set the barrel temperature of the extruder to 170°C in zone 1, 175°C in zone 2, 180°C in zone 3, and 182°C in the die head, the rotation speed to 200r / min, and the feeding rate to 400pph / r, so that the mixture is heated and plasticized in the extruder and extruded to obtain a rubber compound, heat the rubber compound to melt at 200°C, pour the melt into a mold, and demold after curing and molding to obtain a reinforced PVC floor.

[0062] The preparation method of lanthanum aluminate powder is as follows: lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate, and citric acid are weighed in a molar ratio of 0.8:1:2.5, and the lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate, citric acid and water are mixed and stirred at 350 rpm for 20 minutes to obtain a mixed solution, wherein the total metal ion concentration in the mixed solution is 0.1 mol / L; the mixed solution is formed into a gel at a temperature of 80°C and a stirring rate of 500 rpm, and then the temperature is raised to 120°C, the solid is collected and calcined at 600°C for 2 hours, and then ground and sieved to obtain 300-mesh lanthanum aluminate powder.

[0063] The preparation method of the depolymerized lignin derivative is the same as that in Example 1.

[0064] Test Case

[0065] The combustion performance of the reinforced PVC flooring of the embodiment and the comparative example was tested with reference to the standard GB / T 8626-2007 “Test Method for Flammability of Building Materials”. The results are shown in Table 1.

[0066] Table 1 Combustion performance of floor

[0067]

[0068] The test results in Table 1 show that the comparative example, which added flame retardants such as depolymerized lignin derivatives and lanthanum aluminate powder, exhibited the poorest flame retardancy, with its drippings capable of igniting filter paper. In contrast, the addition of molybdenum synergistically improved flame retardancy with the depolymerized lignin derivative. Furthermore, Example 2 exhibited the best flame retardancy, demonstrating the advantages of an appropriate molybdenum doping ratio and mesh size for molybdenum-doped lanthanum aluminate powder. This is because molybdenum doping catalyzes the combustion of PVC, forming a stable carbon layer that inhibits further combustion. The moderate amount of molybdenum-doped lanthanum aluminate powder disperses well in the mixed system, resulting in a more uniform carbon layer structure and further enhancing flame retardancy.

[0069] The wear resistance of the reinforced PVC flooring of the embodiment and comparative example was tested with reference to GB / T 11982.1-2015 “Polyvinyl chloride coil flooring Part 1: Heterogeneous polyvinyl chloride coil flooring”. The results are shown in Table 2.

[0070] Table 2 Wear resistance test results

[0071]

[0072]

[0073] From the test results in Table 2, it can be seen that the embodiment in which molybdenum-doped lanthanum aluminate powder is added has a lower volume loss rate and better wear resistance than the comparative example in which lanthanum aluminate powder is added.

[0074] Place the floor sample to be tested on a flat surface and place a circular load weight on the test sample. Slowly apply a total force of 500N to the sample surface within 2 seconds. Remove the applied force after 150 minutes, and after another 150 minutes, use an instrument to measure the final thickness of the sample to an accuracy of 0.01mm. Test the floor's indentation resistance based on the thickness before and after, and the shrinkage rate is determined by the thickness change. Test the sample's warpage height and size, then place the sample in an oven at 80°C for 6 hours. Then, place the sample at 25°C and 50% relative humidity for 36 hours. Record the sample's warpage height and size, and calculate the shrinkage rate. The indentation resistance and shrinkage rate test results are shown in Table 3.

[0075] Table 3 Indentation resistance and shrinkage test results

[0076] Thickness change (mm) Shrinkage (%) Example 1 -0.03 0.05 Example 2 -0.02 0.03 Example 3 -0.05 0.07 Example 4 -0.04 0.05 Example 5 -0.07 0.09 Comparative Example -0.12 0.12

[0077] From the test results in Table 3, it can be seen that the reinforced PVC floor of Example 2 has the best compressive stability and is not easy to bend or warp.

[0078] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A reinforced PVC floor, characterized in that: The raw materials include the following parts by weight: 80~120 parts of PVC powder, 10~30 parts of plasticizer, 30~60 parts of filler powder, 1~2 parts of lubricant, 1~3 parts of heat stabilizer, 2~5 parts of flame retardant; The filler powder is made by mixing molybdenum-doped lanthanum aluminate powder, calcium carbonate powder and wood powder; The preparation method of the molybdenum-doped lanthanum aluminate powder comprises: A soluble molybdenum salt, a soluble lanthanum salt, a soluble aluminum salt, citric acid and water are mixed to obtain a mixed solution, which is stirred at a temperature of 60-90°C and a stirring rate of 300-500 rpm to form a gel, and then the temperature is raised to 110-130°C, and the solid is collected and calcined at 500-700°C for 1-3 hours, and then ground to obtain molybdenum-doped lanthanum aluminate powder; The molar ratio of soluble molybdenum salt, soluble lanthanum salt, soluble aluminum salt and citric acid is 0.1-0.3:0.7-0.9:1:2-2.5, and the concentration of total metal ions in the mixed solution is 0.05-0.1 mol / L. The flame retardant is a depolymerized lignin derivative; The preparation method of the depolymerized lignin derivative comprises the following steps, calculated in parts by weight: S1, mixing 5-10 parts of depolymerized lignin, 20-50 parts of water, and 0.2-1 parts of triethylenetetramine with stirring for reaction, and collecting insoluble matter to obtain an intermediate product; S2. 5-10 parts of the intermediate product, 2-5 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 0.01-0.05 parts of tin tetrachloride are mixed and stirred for reaction, and insoluble matter is collected to obtain a depolymerized lignin derivative.

2. The reinforced PVC floor according to claim 1, characterized in that: The stirring reaction in step S1 and step S2 is continued for 2 to 5 hours at a temperature of 50 to 90° C. and a stirring rate of 200 to 400 rpm.

3. The reinforced PVC floor according to claim 1, characterized in that: The mass ratio of the molybdenum-doped lanthanum aluminate powder, calcium carbonate powder and wood powder is 2-5:5-10:20-45.

4. The reinforced PVC floor according to claim 1, characterized in that: The mesh size of the molybdenum-doped lanthanum aluminate powder, calcium carbonate powder and wood powder is 50-400 mesh.

5. The reinforced PVC floor according to claim 1, characterized in that: The polymerization degree of the PVC powder is 500-2000.

6. The reinforced PVC floor according to claim 1, characterized in that: The plasticizer is at least one of a citrate plasticizer, an epoxidized plasticizer, and a polyester plasticizer.

7. The reinforced PVC floor according to claim 1, characterized in that: The lubricant is at least one of paraffin wax, stearic acid, monoglyceride, butyl stearate, stearyl alcohol, polyethylene wax, and oxidized polyethylene wax.

8. A method for preparing the reinforced PVC floor according to any one of claims 1 to 7, characterized in that: The following steps are included: PVC powder, plasticizer, filler powder, lubricant, heat stabilizer and flame retardant are dispersed and mixed to obtain expanded powder; The expanded powder is extruded to obtain a rubber compound, which is then heated and melted and poured into a mold for solidification to obtain a reinforced PVC floor.

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