Preparation method of modified calcium-zinc stabilizer for SPC

Abstract

The application discloses a preparation method of a modified calcium-zinc stabilizer for SPC and relates to the technical field of stabilizer preparation. The method comprises the following steps: synthesizing CaSt2@CeSt3 compound, preparing stearic acid modified magnesium-aluminum hydrotalcite, and preparing the modified calcium-zinc stabilizer; the CaSt2@CeSt3 compound is prepared from a calcium stearate suspension, a Ce(NO3)3 solution and a sodium stearate solution; the stearic acid modified magnesium-aluminum hydrotalcite is prepared from stearic acid and magnesium-aluminum hydrotalcite; and the modified calcium-zinc stabilizer is prepared from the following raw materials: stearic acid, nano zinc oxide, CaSt2@CeSt3 compound, stearic acid modified magnesium-aluminum hydrotalcite, monoglyceride, polyethylene wax, pentaerythritol, light calcium carbonate, a mildew inhibitor and an ultraviolet absorption inhibitor. The prepared modified calcium-zinc stabilizer has excellent thermal stability and can effectively enhance the mechanical properties and anti-aging performance of the SPC.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of stabilizer preparation, in particular to a preparation method of modified calcium-zinc stabilizer for SPC. BACKGROUND

[0002] Stone plastic composite (SPC) is a new type of environmentally friendly flooring material made of polyvinyl chloride as the base material, supplemented by inorganic fillers such as calcium powder, through extrusion, calendaring and other processes. Due to its wear resistance, water resistance and no formaldehyde, it is widely used in home and commercial floor decoration. SPC processing needs to go through high temperature of 180-200℃, and the unstable chlorine atoms in the PVC molecular chain are easy to be removed and cause degradation, so it is necessary to add a heat stabilizer to inhibit this process. Calcium-zinc stabilizer becomes the mainstream choice because it does not contain heavy metals such as lead and cadmium, which meets the environmental requirements.

[0003] Calcium-zinc stabilizer usually takes calcium stearate and zinc stearate as the core, and is compounded with lubricants, auxiliary stabilizers, etc., which play a role by capturing HCl generated by degradation and replacing unstable chlorine atoms. However, the existing technology has obvious limitations: zinc ions easily catalyze the degradation of polyvinyl chloride at high temperatures; auxiliary stabilizers are difficult to disperse uniformly, and cannot effectively enhance the mechanical properties; the anti-aging system lacks synergism with the heat stabilizing system. The existing technology with publication number CN118599188A discloses a transparent calcium-zinc stabilizer, its preparation method and application in PVC. This technology mainly relies on the synergism of zinc stearate, calcium stearate and modified silica, and it is difficult to cope with the long-term high temperature environment of 180-200℃ in SPC processing, and the heat stabilizing performance is poor, and the enhancement of mechanical properties is limited, and no synergistic system of heat stabilizing-anti-ultraviolet is formed. The existing technology with publication number CN119241911A discloses an environmentally friendly calcium-zinc composite heat stabilizer and its preparation method. This technology mainly relies on the synergistic effect of beta-diketone, modified organic acid intercalated hydrotalcite and modified silica, and the heat stabilizing efficiency is low, and the improvement of SPC mechanical properties is limited.

[0004] In summary, although the existing technical solutions have improved some properties of calcium-zinc stabilizer to some extent, there are still the following technical problems: poor heat stability, and cannot effectively enhance the mechanical properties and anti-aging properties of SPC. SUMMARY

[0005] In order to solve the above-mentioned problems in the prior art, the present application provides a preparation method of modified calcium-zinc stabilizer for SPC, and achieves the following application purposes: preparing calcium-zinc stabilizer with high heat stability, which can effectively enhance the mechanical properties and anti-aging properties of SPC.

[0006] In order to achieve the above-mentioned purposes, the technical solutions adopted are as follows:

[0007] A preparation method of a modified calcium-zinc stabilizer for SPC, comprising the steps of synthesizing CaSt2@CeSt3 compound, preparing stearic acid modified magnesium-aluminum hydrotalcite, and obtaining the modified calcium-zinc stabilizer.

[0008] The CaSt2@CeSt3 compound is synthesized from a calcium stearate suspension, a Ce(NO3)3 solution, and a sodium stearate solution.

[0009] The stearic acid modified magnesium-aluminum hydrotalcite is prepared by modifying magnesium-aluminum hydrotalcite with stearic acid.

[0010] The modified calcium-zinc stabilizer is obtained by using the following raw materials: stearic acid, nano-zinc oxide, CaSt2@CeSt3 compound, stearic acid modified magnesium-aluminum hydrotalcite, monoglyceride, polyethylene wax, pentaerythritol, light calcium carbonate, mildew inhibitor, and ultraviolet absorption agent.

[0011] The ultraviolet absorption agent is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole, the mildew inhibitor is 1,2-benzisothiazolin-3-one, the monoglyceride is molecularly distilled monoglyceride, and the nano-zinc oxide has a particle size of 50-100 nm.

[0012] The raw materials for obtaining the modified calcium-zinc stabilizer are used in the following proportions by weight: stearic acid 60-80 parts, nano-zinc oxide 5-8 parts, CaSt2@CeSt3 compound 2-5 parts, stearic acid modified magnesium-aluminum hydrotalcite 2-4 parts, monoglyceride 5-10 parts, polyethylene wax 5-10 parts, pentaerythritol 2-5 parts, light calcium carbonate 5-10 parts, mildew inhibitor 1-2 parts, and ultraviolet absorption agent 2-3 parts.

[0013] Further, the CaSt2@CeSt3 compound is synthesized as follows:

[0014] The calcium stearate is dispersed in deionized water at 60-65°C, the solid-liquid ratio of calcium stearate to deionized water is 1:10, ultrasonic treatment is performed at a power of 300-400 W for 10-15 min to obtain a calcium stearate suspension.

[0015] The calcium stearate suspension is heated to 70-80°C, the stirring rate is 800-900 rpm, the Ce(NO3)3 solution is slowly added dropwise, the molar ratio of Ce(NO3)3 to calcium stearate is (2-3):10, the dropwise rate is 2-3 mL / min, after the dropwise addition, the stirring is continued for 10-15 min; then the sodium stearate solution is slowly added dropwise, the molar ratio of sodium stearate to Ce(NO3)3 is (3-3.5):1, the dropwise rate is 3-5 mL / min, during the dropwise addition, the pH value is adjusted to 8-9 with NaOH, after the dropwise addition, the stirring is continued for 1-1.5 h; after the reaction is completed, filtration is performed, and the CaSt2@CeSt3 composite precipitate is obtained. Then the CaSt2@CeSt3 composite precipitate is washed to be neutral with 80-85°C deionized water; after the washing is completed, drying is performed, the temperature is 60-80°C, the drying time is 12-14 h; after the drying is completed, crushing is performed, and then the 200 mesh sieve is passed, and the CaSt2@CeSt3 composite is obtained. The purity of the calcium stearate is ≥98%, and the particle size is 1-5 μm; the Ce(NO3)3 solution is prepared by dissolving Ce(NO3)3·6H2O in deionized water, and the concentration is 0.5 mol / L; the sodium stearate solution is prepared by dissolving sodium stearate in 80-90°C deionized water, and the concentration is 1 mol / L; the concentration of the NaOH solution is 1 mol / L.

[0016] Further, the preparation of the stearic acid modified magnesium-aluminum hydrotalcite:

[0017] The stearic acid is heated to 70-80°C, and the molten stearic acid is obtained; the dried magnesium-aluminum hydrotalcite is added to a high-speed mixer, the temperature is increased to 80-90°C, and the stirring is started, and the rotating speed is 800-1000 rpm; the molten stearic acid is slowly added dropwise into the mixer, the amount of the molten stearic acid is 1-3% of the mass of the magnesium-aluminum hydrotalcite, and the dropwise rate is 5-10 mL / min, after the dropwise addition, the stirring and mixing are continued for 30-60 min; then the crushing machine is used for crushing, and the 200 mesh sieve is passed, and the stearic acid modified magnesium-aluminum hydrotalcite is obtained. The molar ratio of Mg / Al of the magnesium-aluminum hydrotalcite is 3:1, and the particle size is 300-500 nm.

[0018] Further, the preparation of the modified calcium-zinc stabilizer:

[0019] The monoglyceride is heated to 60-70 DEG C to melt, the polyethylene wax is added, heated to 110-120 DEG C to melt, after stirring and mixing, the temperature is lowered to 80-90 DEG C, then the pentaerythritol, light calcium carbonate and nano zinc oxide are added, stirring at a speed of 800-1000 rpm for 15-20 min to obtain mixture A. The reaction kettle is warmed to 70-75 DEG C, preheated for 20-40 min, the stirring is started, the stirring speed is 300-500 rpm, the stearic acid is added, stirred and melted, the temperature is raised to 115-120 DEG C, then mixture A is added, the stirring speed is raised to 600-800 rpm, stirring for 20-40 min, then the temperature is raised to 120-130 DEG C, the CaSt2@CeSt3 compound and the stearic acid modified magnesium-aluminum hydrotalcite are added in sequence, the stirring speed is raised to 800-1000 rpm, and the stirring reaction is carried out for 20-40 min, then the mildew-proof agent and the ultraviolet absorption agent are added, the stirring speed is reduced to 600-800 rpm, and stirring is carried out for 10-20 min, after standing, the material is discharged, and is subjected to a double-roller cooling tablet press to obtain the modified calcium-zinc stabilizer.

[0020] The present application forms a core-shell structure of "CaSt2 as core and CeSt3 as shell" by stepwise dropwise addition reaction, and CeSt3 uniformly coats the surface of CaSt2 in the form of a nano layer. In the prior art, CaSt2 and CeSt3 particles are physically mixed, there is no strong interaction between the particles, and agglomeration or stratification easily occurs due to differences in density and surface energy, and the components are not uniformly distributed. The effect of the calcium-zinc stabilizer depends on the uniform distribution in the matrix; the uneven distribution of the components in the prior art forms a local "weak stabilization zone", which causes SPC to preferentially degrade in the weak zone. In addition, the CaSt2@CeSt3 compound has a core-shell structure, and the shell layer of CeSt3 blocks HCl and free radicals, avoiding the premature oxidation of CaSt2; at the initial stage of high-temperature processing, CeSt3 is consumed from the outside to the inside and plays a role, and CeSt3 gradually participates in the reaction during the processing process, achieving "continuous stabilization" and prolonging the effective life of the stabilizer.

[0021] The beneficial effects of the present application are as follows:

[0022] (1) The modified calcium-zinc stabilizer for SPC has excellent thermal stability. The weight loss rate of the modified calcium-zinc stabilizer prepared by the present application is 1.01-1.35% after heating for 24 h.

[0023] (2) The modified calcium-zinc stabilizer for SPC can effectively improve the mechanical properties of SPC. The tensile strength of the SPC sample prepared by using the modified calcium-zinc stabilizer prepared by the present application as a raw material is 53.3-56.5 MPa, and the elongation at break is 76.9-81.7%.

[0024] (3) The modified calcium-zinc stabilizer for SPC can effectively enhance the anti-aging performance of SPC. After heat aging and ultraviolet aging, the Congo red test paper discoloration time of the SPC sample prepared by using the modified calcium-zinc stabilizer as a raw material is 89-96 min, and the tensile strength retention rate is 92.8-94.5%. DETAILED DESCRIPTION

[0025] In order to make the objects, technical solutions and advantages of the present application clearer, the embodiments of the present application will be further described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0026] Example 1: Preparation method of a modified calcium-zinc stabilizer for SPC

[0027] The preparation method of the modified calcium-zinc stabilizer for SPC comprises the following steps:

[0028] Step one, synthesis of CaSt2@CeSt3 complex

[0029] The calcium stearate is dispersed in deionized water at 60°C, the solid-liquid ratio of calcium stearate to deionized water is 1:10, ultrasonic treatment is performed, the power is 300W, and the ultrasonic treatment is performed for 15min to obtain a calcium stearate suspension.

[0030] The calcium stearate suspension is heated to 70°C, the stirring rate is 800rpm, the Ce(NO3)3 solution is slowly added, the molar ratio of Ce(NO3)3 to calcium stearate is 2:10, the dropwise adding rate is 2mL / min, after the dropwise adding is completed, the stirring reaction is continued for 15min; then the sodium stearate solution is slowly added, the molar ratio of sodium stearate to Ce(NO3)3 is 3:1, the dropwise adding rate is 3mL / min, and the pH value is adjusted to 8 by using NaOH during the dropwise adding process, after the dropwise adding is completed, the stirring reaction is continued for 1.5h; after the reaction is completed, filtration is performed to obtain CaSt2@CeSt3 complex precipitate, then the CaSt2@CeSt3 complex is washed to be neutral by using deionized water at 80°C; after the washing is completed, drying is performed, the temperature is 60°C, the drying time is 14h; after the drying is completed, crushing is performed, then the CaSt2@CeSt3 complex is obtained by passing through a 200 mesh sieve. The purity of the calcium stearate is greater than or equal to 98%, and the particle size is 1-5μm; the Ce(NO3)3 solution is prepared by dissolving Ce(NO3)3·6H2O in deionized water, and the concentration is 0.5mol / L; the sodium stearate solution is prepared by dissolving sodium stearate in deionized water at 80-90°C, and the concentration is 1mol / L; the concentration of the NaOH solution is 1mol / L.

[0031] Step two, preparation of stearic acid modified magnesium-aluminum hydrotalcite

[0032] Stearic acid was heated to 70℃ to obtain molten stearic acid; dry Mg-Al hydrotalcite was added into a high-speed mixer, and the temperature was raised to 80℃, and stirring was started at a speed of 800 rpm; the molten stearic acid was slowly added into the mixer, the molten stearic acid was 1% of the mass of the Mg-Al hydrotalcite, and the dropping speed was 5 mL / min; after the dropping was completed, the stirring was continued for 60 min; after the reaction was completed, drying was performed at a temperature of 80℃ for 3 h; and then the product was crushed by a pulverizer, and sieved through a 200-mesh screen to obtain the stearic acid-modified Mg-Al hydrotalcite. The Mg / Al molar ratio of the Mg-Al hydrotalcite was 3:1, and the particle size was 300-500 nm.

[0033] Step three, the modified calcium-zinc stabilizer was prepared

[0034] The raw materials used for preparing the modified calcium-zinc stabilizer were in a weight ratio of 60 parts of stearic acid, 8 parts of nano-zinc oxide, 5 parts of CaSt2@CeSt3 compound, 4 parts of stearic acid-modified Mg-Al hydrotalcite, 10 parts of monoglyceride, 10 parts of polyethylene wax, 5 parts of pentaerythritol, 10 parts of light calcium carbonate, 2 parts of mildew inhibitor, and 3 parts of anti-ultraviolet absorber.

[0035] The anti-ultraviolet absorber was 2-(2'-hydroxy-5'-methylphenyl)benzotriazole.

[0036] The mildew inhibitor was 1,2-benzisothiazolin-3-one.

[0037] The monoglyceride was molecularly distilled monoglyceride.

[0038] The nano-zinc oxide had a particle size of 50-100 nm.

[0039] The monoglyceride was heated to 60℃ to melt, and the polyethylene wax was added and heated to 110℃ to melt; after the stirring and mixing, the temperature was lowered to 80℃, and then the pentaerythritol, light calcium carbonate, and nano-zinc oxide were added, and stirred at a speed of 800 rpm for 20 min to obtain a mixture A. The reaction kettle was heated to 70℃, and preheated for 40 min; stirring was started at a speed of 300 rpm, and then the stearic acid was added and stirred to melt; the temperature was raised to 115℃; then the mixture A was added, and the stirring speed was raised to 600 rpm, and stirred for 40 min; then the temperature was raised to 120℃, and the CaSt2@CeSt3 compound and the stearic acid-modified Mg-Al hydrotalcite were added in sequence, and the stirring speed was raised to 800 rpm, and stirred for 40 min; then the mildew inhibitor and the anti-ultraviolet absorber were added, and the stirring speed was lowered to 600 rpm, and stirred for 20 min; after the standing, the material was discharged, and passed through a double-roller cooling tablet press to obtain the modified calcium-zinc stabilizer.

[0040] Example 2, a preparation method of a modified calcium-zinc stabilizer for SPC

[0041] A preparation method of a modified calcium-zinc stabilizer for SPC, comprising the following steps:

[0042] Step one, synthesis of CaSt2@CeSt3 composite

[0043] The calcium stearate is dispersed in deionized water at 65℃, the solid-liquid ratio of calcium stearate to deionized water is 1:10, ultrasonic treatment is performed, the power is 400W, and the ultrasonic treatment is performed for 10min to obtain a calcium stearate suspension.

[0044] The calcium stearate suspension is heated to 75℃, the stirring rate is 900rpm, the Ce(NO3)3 solution is slowly added dropwise, the molar ratio of Ce(NO3)3 to calcium stearate is 3:10, the dropwise adding rate is 3mL / min, after the dropwise adding is completed, the stirring reaction is continued for 10min; then the sodium stearate solution is slowly added dropwise, the molar ratio of sodium stearate to Ce(NO3)3 is 3.5:1, the dropwise adding rate is 5mL / min, the pH value is adjusted to 9 by using NaOH during the dropwise adding process, after the dropwise adding is completed, the stirring reaction is continued for 1.5h; after the reaction is completed, filtration is performed to obtain CaSt2@CeSt3 composite precipitate, then the CaSt2@CeSt3 composite is washed to be neutral by using deionized water at 85℃; after the washing is completed, drying is performed, the temperature is 70℃, and the drying time is 14h; after the drying is completed, crushing is performed, then the CaSt2@CeSt3 composite is obtained by passing through a 200 mesh sieve. The purity of the calcium stearate is ≥98%, and the particle size is 1-5μm; the Ce(NO3)3 solution is prepared by dissolving Ce(NO3)3·6H2O in deionized water, and the concentration is 0.5mol / L; the sodium stearate solution is prepared by dissolving sodium stearate in deionized water at 80-90℃, and the concentration is 1mol / L; the concentration of the NaOH solution is 1mol / L.

[0045] Step two, preparation of stearic acid modified magnesium-aluminum hydrotalcite

[0046] The stearic acid is heated to 80℃ to obtain molten stearic acid; the dried magnesium-aluminum hydrotalcite is added into a high-speed mixer, the temperature is increased to 90℃, and the stirring is started with a rotating speed of 1000rpm; the molten stearic acid is slowly added dropwise into the mixer, the molten stearic acid accounts for 3% of the mass of the magnesium-aluminum hydrotalcite, and the dropwise adding rate is 10mL / min; after the dropwise adding is completed, the stirring and mixing are continued for 60min; after the reaction is completed, drying is performed, the temperature is 85℃, and the drying is performed for 3h; then the stearic acid modified magnesium-aluminum hydrotalcite is obtained by crushing with a crusher and passing through a 200 mesh sieve. The molar ratio of Mg / Al of the magnesium-aluminum hydrotalcite is 3:1, and the particle size is 300-500nm.

[0047] Step three, preparation of the modified calcium-zinc stabilizer

[0048] The raw material weight ratio used in the preparation of the modified calcium-zinc stabilizer is: 70 parts of stearic acid, 6 parts of nano-zinc oxide, 4 parts of CaSt2@CeSt3 compound, 3 parts of stearic acid modified magnesium-aluminum hydrotalcite, 8 parts of monoglyceride, 8 parts of polyethylene wax, 4 parts of pentaerythritol, 8 parts of light calcium carbonate, 1.5 parts of mildew inhibitor, and 3 parts of ultraviolet absorption agent.

[0049] The ultraviolet absorption agent is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole.

[0050] The mildew inhibitor is 1,2-benzisothiazolin-3-one.

[0051] The monoglyceride is molecularly distilled monoglyceride.

[0052] The nano-zinc oxide particle size is 50-100 nm.

[0053] The monoglyceride is heated to 70°C to melt, the polyethylene wax is added and heated to 120°C to melt, the mixture is stirred and mixed, then cooled to 90°C, and the pentaerythritol, light calcium carbonate and nano-zinc oxide are added, stirred at a speed of 900 rpm for 15 min to obtain mixture A. The reaction kettle is heated to 75°C, preheated for 20 min, the stirring is started with a stirring rate of 500 rpm, the stearic acid is added, stirred and melted, and heated to 120°C; then mixture A is added, the stirring rate is increased to 700 rpm, and stirred for 30 min; then, heated to 130°C, the CaSt2@CeSt3 compound and the stearic acid modified magnesium-aluminum hydrotalcite are added in sequence, the stirring rate is increased to 900 rpm, and stirred for 30 min; then the mildew inhibitor and the ultraviolet absorption agent are added, the stirring rate is reduced to 700 rpm, and stirred for 10 min; after standing, the material is discharged and passed through a double-roller cooling tablet press to obtain the modified calcium-zinc stabilizer.

[0054] Example 3: A preparation method of a modified calcium-zinc stabilizer for SPC

[0055] A preparation method of a modified calcium-zinc stabilizer for SPC, comprising the following steps:

[0056] Step one, synthesis of CaSt2@CeSt3 compound

[0057] The calcium stearate is dispersed in deionized water at 65°C, the solid-liquid ratio of calcium stearate to deionized water is 1:10, ultrasonic treatment is performed, the power is 400W, and the ultrasonic treatment is performed for 15 min to obtain a calcium stearate suspension.

[0058] The calcium stearate suspension was heated to 80℃, the stirring rate was 900 rpm, the Ce(NO3)3 solution was slowly added dropwise, the molar ratio of Ce(NO3)3 to calcium stearate was 3:10, the dropwise rate was 3 mL / min, after the dropwise addition was completed, the stirring was continued for 10 min; then the sodium stearate solution was slowly added dropwise, the molar ratio of sodium stearate to Ce(NO3)3 was 3.5:1, the dropwise rate was 5 mL / min, during the dropwise addition, the pH value was adjusted to 9 with NaOH, after the dropwise addition was completed, the stirring was continued for 1 h; after the reaction was completed, filtration was performed, the CaSt2@CeSt3 composite precipitate was obtained, then the CaSt2@CeSt3 composite was washed to be neutral with 85℃ deionized water; after the washing was completed, drying was performed, the temperature was 80℃, the drying time was 12 h; after the drying was completed, crushing was performed, then the CaSt2@CeSt3 composite was obtained by passing through a 200 mesh screen. The purity of the calcium stearate is ≥98%, the particle size is 1-5 μm; the Ce(NO3)3 solution is prepared by dissolving Ce(NO3)3·6H2O in deionized water, the concentration is 0.5 mol / L; the sodium stearate solution is prepared by dissolving sodium stearate in 80-90℃ deionized water, the concentration is 1 mol / L; the concentration of the NaOH solution is 1 mol / L.

[0059] Step two, preparation of stearic acid modified magnesium-aluminum hydrotalcite

[0060] The stearic acid was heated to 80℃ to obtain molten stearic acid; the dried magnesium-aluminum hydrotalcite was added to a high-speed mixer, the temperature was increased to 90℃, the stirring was started, the rotating speed was 1000 rpm; the molten stearic acid was slowly added dropwise into the mixer, the amount of the molten stearic acid was 3% of the mass of the magnesium-aluminum hydrotalcite, the dropwise rate was 10 mL / min, after the dropwise addition was completed, the stirring was continued for 30 min; after the reaction was completed, drying was performed, the temperature was 85℃, the drying time was 2 h; then the stearic acid modified magnesium-aluminum hydrotalcite was obtained by crushing with a crusher and passing through a 200 mesh screen. The molar ratio of Mg / Al of the magnesium-aluminum hydrotalcite is 3:1, the particle size is 300-500 nm.

[0061] Step three, preparation of the modified calcium-zinc stabilizer

[0062] The weight ratio of the raw materials used for preparing the modified calcium-zinc stabilizer is as follows: stearic acid 80 parts, nano-zinc oxide 5 parts, CaSt2@CeSt3 composite 2 parts, stearic acid modified magnesium-aluminum hydrotalcite 2 parts, monoglyceride 5 parts, polyethylene wax 5 parts, pentaerythritol 2 parts, light calcium carbonate 5 parts, mildew inhibitor 1 part, anti-ultraviolet absorber 2 parts.

[0063] The anti-ultraviolet absorber is 2-(2'-hydroxy-5'-methylphenyl)benzotriazole.

[0064] The mildew inhibitor is 1,2-benzisothiazolin-3-one.

[0065] The monoglyceride is a molecular distillation monoglyceride.

[0066] The nano zinc oxide has a particle size of 50-100 nm.

[0067] The monoglyceride is heated to 70°C to melt, polyethylene wax is added, heated to 120°C to melt, and then cooled to 90°C, and then pentaerythritol, light calcium carbonate and nano zinc oxide are added, stirred at a speed of 1000 rpm for 15 min to obtain mixture A. The reaction kettle is heated to 75°C, preheated for 20 min, and then stirred at a speed of 500 rpm. Stearic acid is added, stirred and melted, and then heated to 120°C. Then mixture A is added, the stirring speed is increased to 800 rpm, and stirring is performed for 20 min. Then, the temperature is increased to 130°C, and the CaSt2@CeSt3 compound and the stearic acid modified magnesium-aluminum hydrotalcite are added in sequence, the stirring speed is increased to 1000 rpm, and stirring is performed for 20 min. Then the mildew inhibitor and the ultraviolet absorption agent are added, the stirring speed is reduced to 800 rpm, and stirring is performed for 10 min. After standing, the material is discharged and passed through a double-roller cooling tablet press to obtain the modified calcium-zinc stabilizer.

[0068] Comparative Example 1

[0069] A preparation method of a modified calcium-zinc stabilizer, comprising the following steps:

[0070] Step one, preparation of stearic acid modified magnesium-aluminum hydrotalcite

[0071] This step is the same as the "preparation of stearic acid modified magnesium-aluminum hydrotalcite" operation in Example 2.

[0072] Step two, preparation of a modified calcium-zinc stabilizer

[0073] The weight ratio of the raw materials used to prepare the modified calcium-zinc stabilizer is as follows: stearic acid 70 parts, nano zinc oxide 6 parts, calcium stearate 4 parts, stearic acid modified magnesium-aluminum hydrotalcite 3 parts, monoglyceride 8 parts, polyethylene wax 8 parts, pentaerythritol 4 parts, light calcium carbonate 8 parts, mildew inhibitor 1.5 parts, and ultraviolet absorption agent 3 parts.

[0074] The ultraviolet absorption agent is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole.

[0075] The mildew inhibitor is 1,2-benzisothiazolin-3-one.

[0076] The monoglyceride is a molecular distillation monoglyceride.

[0077] The nano zinc oxide has a particle size of 50-100 nm.

[0078] The calcium stearate has a purity of ≥98% and a particle size of 1-5 μm.

[0079] The monoglyceride was heated to 70℃ to melt, the polyethylene wax was added, heated to 120℃ to melt, after stirring and mixing, the temperature was lowered to 90℃, then the pentaerythritol, light calcium carbonate and nano zinc oxide were added, and stirred at a speed of 900 rpm for 15 min to obtain mixture A. The reaction kettle was warmed to 75℃, preheated for 20 min, and then the stirring was started at a speed of 500 rpm. The stearic acid was added, stirred and melted, and then the temperature was raised to 120℃. Then mixture A was added, and the stirring speed was raised to 700 rpm, and stirred for 30 min. Then the temperature was raised to 130℃, and the calcium stearate and the stearic acid modified magnesium-aluminum hydrotalcite were added in sequence, and the stirring speed was raised to 900 rpm, and stirred for 30 min. Then the mildew inhibitor and the ultraviolet absorption agent were added, and the stirring speed was reduced to 700 rpm, and stirred for 10 min. After standing, the material was discharged, and passed through a double roller cooling tablet machine to obtain the modified calcium-zinc stabilizer.

[0080] Comparative Example 2

[0081] A preparation method of a modified calcium-zinc stabilizer, comprising the following steps:

[0082] Step one, synthesis of CaSt2@CeSt3 complex

[0083] This step is the same as the operation of "synthesis of CaSt2@CeSt3 complex" in Example 2.

[0084] Step two, preparation of the modified calcium-zinc stabilizer

[0085] The weight ratio of the raw materials used to prepare the modified calcium-zinc stabilizer is as follows: stearic acid 70 parts, nano zinc oxide 6 parts, CaSt2@CeSt3 complex 4 parts, magnesium-aluminum hydrotalcite 3 parts, monoglyceride 8 parts, polyethylene wax 8 parts, pentaerythritol 4 parts, light calcium carbonate 8 parts, mildew inhibitor 1.5 parts, and ultraviolet absorption agent 3 parts.

[0086] The ultraviolet absorption agent is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole.

[0087] The mildew inhibitor is 1,2-benzisothiazolin-3-one.

[0088] The monoglyceride is molecularly distilled monoglyceride.

[0089] The nano zinc oxide has a particle size of 50-100 nm.

[0090] The magnesium-aluminum hydrotalcite has a Mg / Al molar ratio of 3:1 and a particle size of 300-500 nm.

[0091] The monoglyceride is heated to 70℃ to melt, the polyethylene wax is added, heated to 120℃ to melt, after stirring and mixing, the temperature is lowered to 90℃, then the pentaerythritol, light calcium carbonate and nano zinc oxide are added, and stirring is carried out at a speed of 900 rpm for 15 min to obtain mixture A. The reaction kettle is warmed to 75℃, preheated for 20 min, and stirring is started with a stirring speed of 500 rpm, then the stearic acid is added, stirred and melted, and the temperature is raised to 120℃; then the mixture A is added, the stirring speed is raised to 700 rpm, and stirring is carried out for 30 min; then the temperature is raised to 130℃, and the CaSt2@CeSt3 composite and magnesium-aluminum hydrotalcite are added in sequence, the stirring speed is raised to 900 rpm, and stirring reaction is carried out for 30 min; then the mildew inhibitor and the ultraviolet absorption agent are added, the stirring speed is reduced to 700 rpm, and stirring is carried out for 10 min; after standing, the material is discharged, and is subjected to a double-roller cooling tablet press to obtain the modified calcium-zinc stabilizer.

[0092] Example 4 Performance test

[0093] (1) The modified calcium-zinc stabilizers prepared in Examples 1-3 and Comparative Examples 1-2 are subjected to thermal stability test. The modified calcium-zinc stabilizers are heated to 180-200℃, and the weight loss rate is calculated after 24 h of heat preservation. The specific test results are shown in Table 1.

[0094] Table 1

[0095]

[0096] As shown by the test results in Table 1, the weight loss rate of the modified calcium-zinc stabilizers prepared in Examples 1-3 and Comparative Examples 1-2 is 1.01-1.35% after 24 h of heating, which proves that the modified calcium-zinc stabilizer prepared in the application has excellent thermal stability.

[0097] (2) The modified calcium-zinc stabilizers prepared in Examples 1-3 and Comparative Examples 1-2 are used as raw materials to prepare SPC samples, and the weight ratio of the raw materials is as follows: PVC resin 50 parts, calcium powder 150 parts, back material 30 parts, modified calcium-zinc stabilizer 5 parts, lubricant 2.0 parts, and acrylic ester copolymer 3.5 parts. The SPC samples are subjected to mechanical property test: the tensile strength and elongation at break of the SPC samples are tested according to the test method specified in GB / T 1040. The specific test results are shown in Table 2.

[0098] Table 2

[0099]

[0100] From the test results of Table 2, it can be seen that the SPC samples prepared by using the modified calcium-zinc stabilizer prepared in Examples 1-3 and Comparative Examples 1-2 as raw materials have a tensile strength of 53.3-56.5 MPa and an elongation at break of 76.9-81.7%, which proves that the SPC samples prepared by using the modified calcium-zinc stabilizer prepared in the application as raw materials have excellent mechanical properties.

[0101] (Three) The prepared SPC samples were subjected to heat aging test: the SPC samples were heated at 200℃, and the Congo red test paper discoloration time was recorded; the prepared SPC samples were subjected to ultraviolet aging test: after irradiation in an ultraviolet aging box for 1000h according to the test method specified in GB / T 16422, the tensile strength retention rate of the SPC samples was tested. The specific test results are shown in Table 3.

[0102] Table 3

[0103]

[0104] From the test results of Table 3, it can be seen that the SPC samples prepared by using the modified calcium-zinc stabilizer prepared in Examples 1-3 and Comparative Examples 1-2 as raw materials have a Congo red test paper discoloration time of 89-96min and a tensile strength retention rate of 92.8-94.5% after heat aging and ultraviolet aging, which proves that the SPC samples prepared by using the modified calcium-zinc stabilizer prepared in the application as raw materials have excellent anti-aging properties.

[0105] Obviously, there are still many specific implementation methods that can be changed under the concept of the application, and here it should be declared that any changes made under the inventive concept of the application will fall within the protection scope of the application.

Claims

1. A method for preparing a modified calcium-zinc stabilizer for SPC, characterized by: The steps of synthesizing CaSt2@CeSt3 composite, preparing stearic acid modified magnesium-aluminum hydrotalcite, and preparing modified calcium-zinc stabilizer are included. The CaSt2@CeSt3 composite is synthesized by heating a calcium stearate suspension to 70-80 DEG C, stirring at a speed of 800-900 rpm, slowly adding a Ce(NO3)3 solution, continuing to stir for 10-15 min after the addition is completed, then slowly adding a sodium stearate solution, adjusting the pH to 8-9 with NaOH during the addition, and continuing to stir for 1-1.5 h after the addition is completed. The stearic acid modified magnesium-aluminum hydrotalcite is prepared by modifying magnesium-aluminum hydrotalcite with stearic acid. The modified calcium-zinc stabilizer is prepared by using stearic acid, nano zinc oxide, CaSt2@CeSt3 composite, stearic acid modified magnesium-aluminum hydrotalcite, monoglyceride, polyethylene wax, pentaerythritol, light calcium carbonate, mildew inhibitor, and ultraviolet absorption inhibitor.

2. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The modified calcium-zinc stabilizer is prepared by using stearic acid, nano zinc oxide, CaSt2@CeSt3 composite, stearic acid modified magnesium-aluminum hydrotalcite, monoglyceride, polyethylene wax, pentaerythritol, light calcium carbonate, mildew inhibitor, and ultraviolet absorption inhibitor.

3. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The calcium stearate suspension is prepared by dispersing calcium stearate in deionized water at 60-65 DEG C, with a solid-liquid ratio of 1:10, and then ultrasonic treatment for 10-15 min.

4. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The molar ratio of Ce(NO3)3 to calcium stearate is (2-3):

10.

5. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The molar ratio of sodium stearate to Ce(NO3)3 is (3-3.5):

1.

6. The method of preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The stearic acid modified magnesium-aluminum hydrotalcite is prepared by heating stearic acid to 70-80 DEG C to obtain molten stearic acid, adding dry magnesium-aluminum hydrotalcite to a high-speed mixer, heating to 80-90 DEG C, and stirring at a speed of 800-1000 rpm, slowly adding the molten stearic acid into the mixer, and continuing to stir and mix for 30-60 min after the addition is completed.

7. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 6, characterized in that: The amount of molten stearic acid added to the mixer is 1-3% of the mass of the magnesium-aluminum hydrotalcite.

8. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The prepared modified calcium-zinc stabilizer: the monoglyceride is heated to 60-70 DEG C to melt, polyethylene wax is added, heated to 110-120 DEG C to melt, after mixing and stirring, the temperature is lowered to 80-90 DEG C, then pentaerythritol, light calcium carbonate and nano zinc oxide are added, stirring for 15-20 min, to obtain mixture A; the reaction kettle is heated to 70-75 DEG C, preheated for 20-40 min, and then the stirring is started, stearic acid is added, and stirred to melt, and then the temperature is raised to 115-120 DEG C; then mixture A is added, the stirring rate is raised to 600-800 rpm, and stirring is carried out for 20-40 min; then the temperature is raised to 120-130 DEG C, and CaSt2@CeSt3 compound and stearic acid modified magnesium-aluminum hydrotalcite are added in sequence, the stirring rate is raised to 800-1000 rpm, and stirring reaction is carried out for 20-40 min; then the mildew inhibitor and the ultraviolet absorption agent are added, the stirring rate is lowered to 600-800 rpm, and stirring is carried out for 10-20 min; after standing, the material is discharged, and passed through a double-roller cooling tablet machine to obtain the modified calcium-zinc stabilizer.

9. The method for preparing a modified calcium-zinc stabilizer for SPC according to claim 1, characterized in that: The ultraviolet absorption agent is 2-(2'-hydroxy-5'-methylphenyl) benzotriazole; and the mildew inhibitor is 1,2-benzisothiazolin-3-one.

Images