A powdered calcium zinc stabilizer for paste, and its preparation method and application

Abstract

The present invention belongs to the field of PVC heat stabilizers and specifically relates to a powdered calcium-zinc stabilizer for slurry, its preparation method, and application. The stabilizer comprises 15%-30% coating-grade zinc stearate, 15%-30% coating-grade calcium stearate, 35%-60% zeolite, 3%-10% antioxidant, and 3%-10% co-stabilizer, wherein the percentages are by mass. The present invention adjusts the formula composition, the proportion of each component, and the preparation process to obtain a powdered calcium-zinc stabilizer having excellent heat resistance while preventing a rapid increase in the viscosity of the slurry system.

Description

Technical Field

[0001] The invention belongs to the field of PVC heat stabilizers, and particularly relates to a powdered calcium zinc stabilizer for paste, a preparation method and an application thereof. Background Art

[0002] Polyvinyl chloride (PVC) is a general-purpose plastic used in a wide variety of fields. Depending on its application, it requires different molding processes, such as injection molding, extrusion, calendering, blow molding, and coating. Products produced using these different molding processes exhibit excellent physical properties and chemical stability in different applications. However, PVC requires the addition of stabilizers during all molding processes to prevent degradation. Stabilizers can be categorized as powdered or liquid based on their form.

[0003] Liquid stabilizers are categorized as barium-cadmium-zinc stabilizers, barium-zinc stabilizers, calcium-zinc stabilizers, and organotin stabilizers. Liquid barium-cadmium-zinc, liquid barium-zinc, and liquid organotin stabilizers are all toxic and environmentally unfriendly. Liquid calcium-zinc stabilizers, while environmentally friendly, are also relatively expensive. Powdered calcium-zinc stabilizers, however, are widely used due to their low cost and environmental friendliness. However, the application of conventional powdered calcium-zinc stabilizers is still primarily limited to extrusion and some calendered products. The addition of powdered calcium-zinc stabilizers to coated products increases the viscosity of the paste. Current paste systems still primarily rely on liquid barium-zinc stabilizers (for example, the Chinese patent entitled "A Transparent Paste for Preparing PVC Mesh Fabric," Publication No. CN115354503B, utilizes a liquid barium-zinc stabilizer). Consequently, an environmentally friendly powdered stabilizer suitable for paste systems is urgently needed. Summary of the Invention

[0004] In response to the shortcomings and deficiencies of the prior art, the present invention aims to provide a powdered calcium-zinc stabilizer for pastes, its preparation method, and its application. By adjusting the formulation, component ratios, and preparation process, a powdered calcium-zinc stabilizer with excellent heat resistance is obtained without causing a rapid increase in the paste system's viscosity.

[0005] To solve the above technical problems, one object of the present invention is to provide a powdered calcium zinc stabilizer for paste, comprising 15%-30% coating-grade zinc stearate, 15%-30% coating-grade calcium stearate, 35%-60% zeolite, 3%-10% antioxidant, and 3%-10% co-stabilizer, where the percentages are by mass.

[0006] Coating-grade stearates focus on fine particle size, good dispersibility, and compatibility with other raw materials. In paste systems, high dispersibility and compatibility with other raw materials are required, so coating-grade stearates are selected.

[0007] In a preferred embodiment, the preparation process of the powdered calcium zinc stabilizer for paste is as follows: zeolite is treated to remove moisture from the zeolite, the treated zeolite is mixed with a portion of coating-grade zinc stearate so that the porous structure and hydroxyl groups on the surface of the zeolite are covered with coating-grade zinc stearate (the verification of the coating property is carried out by placing it in an aqueous phase, the uncoated zeolite will sink to the bottom of the water, the coated zeolite will float on the upper layer, and the coating rate can be roughly judged based on the ratio of the zeolite floating on the upper layer to the zeolite sinking to the bottom of the water), and then the remaining coating-grade zinc stearate and coating-grade calcium stearate, antioxidant, and stabilizer are added and mixed to obtain the powdered calcium zinc stabilizer for paste; the mass ratio of the portion of coating-grade zinc stearate to zeolite is 1: (5-11).

[0008] Furthermore, the particle size of the zeolite is 3-5 μm; and the zeolite is 4A zeolite.

[0009] In a preferred embodiment, the powdered calcium zinc stabilizer for the paste is composed of 17.9%-21% coating-grade zinc stearate, 17.9%-21% coating-grade calcium stearate, 42%-52% zeolite, 5%-8% antioxidant, and 6%-10% stabilizer.

[0010] Furthermore, the antioxidant is a mixture of one or more of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), and phosphite in any proportion; the co-stabilizer is a mixture of one or more of stearylbenzoylmethane, dibenzoylmethane, and 1-phenyldecane-1,3-dione in any proportion.

[0011] Another object of the present invention is to disclose a method for preparing a powdered calcium zinc stabilizer for paste, specifically: treating zeolite at not less than 100°C (preferably 100-120°C) for 4-6 minutes to remove moisture from the zeolite (maintaining a rotation speed of 550-650 rpm during this process), mixing the treated zeolite with a portion of coating-grade zinc stearate at not less than 100°C (preferably 100-120°C) so that the porous structure and hydroxyl groups on the surface of the zeolite are covered by the coating-grade zinc stearate (maintaining a rotation speed of 550-650 rpm during this process), then adding the remaining coating-grade zinc stearate and coating-grade calcium stearate, an antioxidant, and a stabilizer and mixing at 25°C-45°C (maintaining a rotation speed of 550-650 rpm during this process) to obtain a powdered calcium zinc stabilizer for paste.

[0012] The reason for using coating-grade zinc stearate instead of coating-grade calcium stearate to coat zeolite is that coating-grade zinc stearate has a smaller particle size than calcium stearate, resulting in a better coating effect. Furthermore, zinc stearate has a lower melting point than calcium stearate, requiring less energy for coating. A small amount of coating-grade zinc stearate is used in combination with zeolite because only a portion of the coating-grade zinc stearate is needed to coat the zeolite. Adding all the coating-grade zinc stearate would affect the zinc stearate's ability to act as a primary stabilizer after coating the zeolite. (Adding all the coating-grade zinc stearate would result in different coating ratios each time, with zinc stearate acting as the primary stabilizer providing more coating and zinc stearate acting as the standalone stabilizer providing less, resulting in poorer overall thermal stability.) Compared to ordinary plastic-grade zinc stearate, coating-grade zinc stearate has a smaller particle size, making it easier to reach a molten state, resulting in a better coating effect.

[0013] Zeolite treatment uses a temperature of at least 100°C (preferably 100-120°C) to remove moisture while controlling power consumption. Zeolite coating with coating-grade zinc stearate requires a temperature of at least 100°C (preferably 100-120°C) because zinc stearate is molten under these conditions. Lower temperatures prevent the zinc from melting, resulting in poor coating results. Higher temperatures, however, result in excessive energy consumption.

[0014] The speed of 550-650rpm is used because the raw materials used are all powders with uneven particle sizes. If the speed is too low, it will lead to uneven mixing. If the speed is too high, the high speed of the high-speed mixer during the mixing process will cause the material to deform due to convection, diffusion and shear motion, making it impossible to achieve uniform mixing.

[0015] The duration of zeolite treatment is crucial. If the treatment time is too short, the water will not be completely evaporated; if it is too long, power consumption and costs will increase.

[0016] In a preferred embodiment, the zeolite is treated by mixing a portion of coating grade zinc stearate to zeolite in a mass ratio of 1:(5-11).

[0017] More specifically, zeolite is first added to a high-mix equipment and mixed at 600 rpm and 105°C for 5 minutes (involving the first mixing), then a small amount of zinc stearate is added and mixed at 600 rpm and 105°C for 5 minutes (involving the second mixing), and after mixing, the temperature is cooled (i.e., to 25°C-45°C. If the temperature is not cooled, the performance of the additives will be affected, for example, stearylbenzoylmethane and dibenzoylmethane melt at high temperatures), and finally the remaining components are added and mixed at 600 rpm and 25°C-45°C for 10 minutes (involving the third mixing).

[0018] The mixing temperature of 25℃-45℃ is the best temperature to ensure the performance of the stabilizer product; if the mixing temperature is too high, some additives will be affected, which will affect the heat resistance of the product.

[0019] Another object of the present invention is to provide a PVC paste comprising the aforementioned powdered calcium zinc stabilizer for paste.

[0020] Furthermore, the PVC paste is prepared by mixing 80-120 parts of PVC paste resin, 50-70 parts of DINP (diisononyl phthalate) monomer, 3-5 parts of adhesive, and 1-2 parts of powdered calcium zinc stabilizer for paste.

[0021] In a preferred embodiment, the adhesive may be an isocyanate adhesive.

[0022] The last object of the present invention is to disclose the use of the aforementioned powdered calcium zinc stabilizer for paste in the preparation of PVC paste.

[0023] Compared with the existing technology, the present invention has the following beneficial effects: first, the zeolite is treated at a temperature of not less than 100°C to evaporate the water in the zeolite, then a small amount of coating-grade zinc stearate is mixed with the zeolite, and the mixing of the two will cover the porous structure on the surface of the zeolite with the coating-grade zinc stearate, and finally the remaining raw materials are added. First, the porous structure of the zeolite is coated, and its ability to absorb the solvent of the system is reduced, which will not cause the viscosity of the paste to increase; secondly, the evaporation of the contained water and the coating of the porous structure will greatly improve the water absorption property of the zeolite itself, reduce the amount of water absorbed, and enhance its ability to absorb hydrogen chloride (HCl), thereby improving the thermal stability of the stabilizer; the coating-grade zinc stearate also coats the hydroxyl structure on the surface of the zeolite, thereby reducing the reaction between the hydroxyl group and the adhesive, thereby ensuring that the viscosity of the paste does not increase. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is the dynamic thermal stability test result of composite powder calcium zinc stabilizer (color value);

[0025] Figure 2 This is the test result of the heat resistance of the composite powder calcium zinc stabilizer. DETAILED DESCRIPTION

[0026] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments and drawings. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0027] In the embodiment, the coating-grade zinc stearate is Shafeng (Anhui Shafeng New Materials Co., Ltd.) T580 zinc stearate, and the coating-grade calcium stearate is Shafeng G130 calcium stearate. Any commercially available coating-grade zinc stearate or coating-grade calcium stearate can achieve the purpose of the invention.

[0028] The PVC resin powder used in the embodiment is SG-5 type, and the object of the invention can also be achieved by using SG-3 type, SG-7 type or other PVC resin powders.

[0029] The purpose of the invention can also be achieved by replacing the adhesive in the embodiment with any other commercially available adhesive.

[0030] When treating zeolite to remove moisture in the examples, the moisture removal was verified using a rapid moisture meter with a graduation value of 1 mg, 0.01% at a temperature of 105° C. and an end condition of 1 mg / 60 s. Before treatment, the moisture removal was approximately 3% L, and after treatment, the moisture removal was approximately 0.3% L.

[0031] Example 1

[0032] A composite powder calcium zinc stabilizer, the raw materials of the powder stabilizer are composed of the following components by mass percentage:

[0033] Table 1 Composition of the powdered calcium zinc stabilizer of Example 1

[0034]

[0035] The zeolite particle size is 3 μm (measured by a particle size distribution analyzer D50 or D75); the zeolite is 4A zeolite. The antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; and the stabilizer is stearoylbenzoylmethane.

[0036] First, add all the zeolite into the high-mix equipment (i.e., high-speed mixer), mix at 600 rpm and 105°C for 5 minutes, then add 5% coating-grade zinc stearate (5% refers to the mass percentage of the added coating-grade zinc stearate in the powder calcium zinc stabilizer), mix at 600 rpm and 105°C for 5 minutes, cool to 25°C after mixing, and finally add the remaining coating-grade zinc stearate and remaining components, and mix at 600 rpm and 25°C for 10 minutes.

[0037] Example 2

[0038] A composite powder calcium zinc stabilizer, the raw materials of the powder stabilizer are composed of the following components by mass percentage:

[0039] Table 2 Composition of the powdered calcium zinc stabilizer of Example 2

[0040]

[0041] The particle size of the zeolite is 4 μm; the zeolite is 4A zeolite. The antioxidant is β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate; and the stabilizer is dibenzoylmethane.

[0042] First, add all the zeolite into the high mixing equipment, mix at 600 rpm and 105 ° C for 5 minutes, then add 6% coating grade zinc stearate, mix at 600 rpm and 105 ° C for 5 minutes, cool to 35 ° C after mixing, and finally add the remaining coating grade zinc stearate and remaining components, mix at 600 rpm and 35 ° C for 10 minutes.

[0043] Example 3

[0044] A composite powder calcium zinc stabilizer, the raw materials of the powder stabilizer are composed of the following components by mass percentage:

[0045] Table 3 Composition of the powdered calcium zinc stabilizer of Example 3

[0046]

[0047] The particle size of the zeolite is 5 μm; the zeolite is 4A zeolite; the antioxidant is 2,2'-methylenebis(4-methyl-6-tert-butylphenol); and the stabilizer is 1-phenyldecane-1,3-dione.

[0048] First, add all the zeolite into the high mixing equipment, mix at 600 rpm and 105 ° C for 5 minutes, then add 8% coating grade zinc stearate, mix at 600 rpm and 105 ° C for 5 minutes, cool to 45 ° C after mixing, and finally add the remaining coating grade zinc stearate and remaining components, mix at 600 rpm and 45 ° C for 10 minutes.

[0049] Example 4

[0050] A composite powder calcium zinc stabilizer is basically the same as Example 1, except that the preparation process is modified as follows:

[0051] First, add all the zeolite and 5% coating-grade zinc stearate (5% refers to the mass percentage of the added coating-grade zinc stearate in the powder calcium zinc stabilizer) into the high-mix equipment (i.e., high-speed mixer), mix at 600 rpm and 105°C for 10 minutes, cool to 25°C after mixing, and finally add the remaining coating-grade zinc stearate and remaining components, and mix at 600 rpm and 25°C for 10 minutes.

[0052] When zeolite is coated with zinc stearate, it is mixed at 105°C. During this process, a small amount of water will evaporate from the zeolite due to heating, but it obviously cannot achieve the effect of treating zeolite alone.

[0053] Example 5

[0054] A composite powder calcium zinc stabilizer is basically the same as Example 1, except that the preparation process is modified as follows:

[0055] First, add zeolite into the high mixing equipment, mix at 600 rpm and 105°C for 10 minutes, cool to 25°C after mixing, then add coating-grade zinc stearate and the remaining components, and mix at 600 rpm and 25°C for 10 minutes.

[0056] Example 6

[0057] A composite powder calcium zinc stabilizer is basically the same as Example 1, except that the raw materials of calcium stearate and zinc stearate are changed, wherein coating-grade zinc stearate is replaced by plastic-grade zinc stearate (Shafeng T520), and coating-grade calcium stearate is replaced by plastic-grade calcium stearate (Shafeng G120).

[0058] Comparative Example

[0059] To simulate a commercially available powdered calcium-zinc stabilizer, 17.9% plastic-grade zinc stearate, 17.9% plastic-grade calcium stearate, 50% zeolite, 8% antioxidant, and 6.2% stabilizer were added to a high-mix mixer and mixed at 600 rpm and 25°C for 10 minutes. The zeolite had a particle size of 3 μm and was 4A zeolite. The antioxidant was pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], and the stabilizer was stearoylbenzoylmethane.

[0060] Next, the dynamic thermal stability, paste opening time and temperature resistance of the composite calcium zinc powder stabilizer were tested.

[0061] Example 7 Dynamic Thermal Stability Test of Composite Calcium Zinc Powder Stabilizer

[0062] Production formula:

[0063] Experimental group 7-1: PVC resin powder 50 phr, DINP (diisononyl phthalate) monomer 19 phr, epoxidized soybean oil 1 phr, composite powder calcium zinc stabilizer prepared in Example 1 1 phr;

[0064] Experimental group 7-2: 50 phr of PVC resin powder, 19 phr of DINP monomer, 1 phr of epoxidized soybean oil, and 1 phr of the composite powder calcium zinc stabilizer prepared in Example 2;

[0065] Experimental group 7-3: 50 phr of PVC resin powder, 19 phr of DINP monomer, 1 phr of epoxidized soybean oil, and 1 phr of the composite powder calcium zinc stabilizer prepared in Example 3;

[0066] Control group 1: 50 phr of PVC resin powder, 19 phr of DINP monomer, 1 phr of epoxidized soybean oil, and 1 phr of the composite powder calcium zinc stabilizer prepared in Example 4;

[0067] Control group 2: 50 phr of PVC resin powder, 19 phr of DINP monomer, 1 phr of epoxidized soybean oil, and 1 phr of the composite powder calcium zinc stabilizer prepared in Example 5;

[0068] Control group 3: 50 phr of PVC resin powder, 19 phr of DINP monomer, 1 phr of epoxidized soybean oil, and 1 phr of the composite powder calcium zinc stabilizer prepared in Example 6;

[0069] Control group 4: 50 phr of PVC resin powder, 19 phr of DINP monomer, 1 phr of epoxidized soybean oil, and 1 phr of the composite powder calcium zinc stabilizer prepared in the comparative example;

[0070] The conditions of the twin-roll mill for tableting were: 185°C, 23*18 rpm, and 0.4 mm interaxial distance.

[0071] According to the formulations of experimental groups 7-1, 7-2, 7-3 and control groups 1, 2, 3, 4, mixing was continued for 30 minutes at 185°C, 23*18 rpm, and spindle spacing of 0.4 mm. Samples were taken every 5 minutes and the color value was measured (referring to standard HG / T 3862-2006 Plastic Yellowness Index Test Method). The results are as follows Figure 1 As shown in Table 4 (times of 5, 10, 15, 20, and 25 minutes), experimental groups 7-1, 7-2, and 7-3 all exhibited superior dynamic thermal stability compared to controls 1, 2, and 4. Control group 1, which did not undergo dewatering, and control group 2, which did not undergo coating, exhibited inferior thermal stability compared to the experimental group. Control group 4, which did not undergo dewatering or coating, also exhibited significantly inferior thermal stability compared to the experimental group.

[0072] Table 4 Color value measurement results of experimental group and control group (b*)

[0073]

[0074] Example 8: Test on the Heat Resistance and Open Time of Composite Calcium-Zinc Powder Stabilizer

[0075] Beating formula:

[0076] Experimental group 8-1: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 1;

[0077] Experimental group 8-2: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 2;

[0078] Experimental group 8-3: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 3;

[0079] Experimental group 8-4: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF MIPS (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 3;

[0080] Experimental group 8-5: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF M20S (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 3;

[0081] Control group 5: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 4;

[0082] Control group 6: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 5;

[0083] Control group 7: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in Example 6;

[0084] Control group 8: 100 phr of PVC paste resin powder, 60 phr of DINP monomer, 4 phr of BASF T80 (an adhesive), and 1.5 phr of the composite powder calcium zinc stabilizer prepared in the comparative example;

[0085] Among them, BASF T80, BASF M20S and BASF MIPS are all commercially available isocyanate adhesives.

[0086] Beating process: stirring speed 2500r / min, room temperature, stirring for 5 minutes.

[0087] Opening hours test:

[0088] Use a rotational viscometer with a 3# rotor at 6 rpm for viscosity testing (reference standard: GB / T 2794-2022 Determination of viscosity of adhesives).

[0089] The test results are shown in Table 5:

[0090] Table 5 Opening time test results

[0091]

[0092] The test values in Table 4 are in units of mPa.s, where min refers to min.

[0093] As can be seen from Table 4, the open time of the slurry with the self-developed composite powder calcium zinc stabilizer is much better than that of the control group 8 with the slurry added with a powder calcium zinc stabilizer close to the commercially available one; the control group 5 was not dewatered, and its viscosity was limited; the control group 6 was not coated, and its zeolite surface porous structure easily absorbed the system solvent, and its surface hydroxyl groups reacted with the adhesive, resulting in a higher viscosity; the control group 7 used plastic-grade stearate, which had a higher viscosity; the control group 8 was not dewatered or coated, and also used plastic-grade stearate. The entire system absorbed more solvent, and the surface hydroxyl groups reacted with the adhesive, so the viscosity was the largest and the open time was the shortest.

[0094] Temperature resistance test:

[0095] Use a scraper to apply 660g / ㎡ on the mesh, bake in an oven at 200℃ for 2 minutes to cure, and place in an oven at 80℃ for 5 days for heat resistance test. The results are as follows Figure 2 The product was placed in an 80℃ oven for 5 days to accelerate the aging process. The smaller the color change and the lower the yellowing degree of the final product, the better the stability. Figure 2 It can be seen that the heat resistance of the self-developed composite calcium zinc powder stabilizer is significantly better than that of the control group 8, which is close to the commercially available calcium zinc stabilizer. The control groups 5 and 6 have weaker ability to absorb hydrogen chloride, so their temperature resistance is also slightly worse. The temperature resistance of the control group 7 is close to that of the experimental group.

[0096] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the scope of protection of the present invention.

Claims

1. A PVC paste comprising a powdered calcium zinc stabilizer for paste, characterized in that: The PVC paste is prepared by mixing 80-120 parts of PVC paste resin, 50-70 parts of DINP (diisononyl phthalate) monomer, 3-5 parts of adhesive, and 1-2 parts of powdered calcium zinc stabilizer for paste; the adhesive is an isocyanate adhesive; The powdered calcium zinc stabilizer for paste is composed of 15%-30% coating grade zinc stearate, 15%-30% coating grade calcium stearate, 35%-60% zeolite, 3%-10% antioxidant, and 3%-10% auxiliary stabilizer, where the percentages are by mass. The preparation process of the powdered calcium zinc stabilizer for paste is as follows: treating zeolite at a temperature not lower than 100° C. for 4-6 minutes to remove moisture from the zeolite, mixing the treated zeolite with a portion of coating-grade zinc stearate at a temperature not lower than 100° C. so that the porous structure and hydroxyl groups on the surface of the zeolite are covered by the coating-grade zinc stearate, then adding the remaining coating-grade zinc stearate, coating-grade calcium stearate, antioxidant, and stabilizer, and mixing at a temperature of 25° C.-45° C. to obtain the powdered calcium zinc stabilizer for paste; The mass ratio of a portion of coating grade zinc stearate to zeolite is 1:(5-11).

2. The PVC paste containing a powdered calcium zinc stabilizer for paste according to claim 1, characterized in that: The particle size of the zeolite is 3-5 μm; the zeolite is 4A zeolite.

3. The PVC paste containing powdered calcium zinc stabilizer for paste according to claim 1, characterized in that: The powdered calcium zinc stabilizer for the paste is composed of 17.9%-21% of coating-grade zinc stearate, 17.9%-21% of coating-grade calcium stearate, 42%-52% of zeolite, 5%-8% of antioxidant, and 6%-10% of stabilizer.

4. The PVC paste containing a powdered calcium zinc stabilizer for paste according to claim 1, characterized in that: The antioxidant is one or more of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], n-octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), and phosphite; The auxiliary stabilizer is one or more of stearylbenzoylmethane, dibenzoylmethane, and 1-phenyldecane-1,3-dione.

5. A method for preparing a PVC paste containing a powdered calcium zinc stabilizer for the paste, characterized in that: The PVC paste is prepared by mixing 80-120 parts of PVC paste resin, 50-70 parts of DINP (diisononyl phthalate) monomer, 3-5 parts of adhesive, and 1-2 parts of powdered calcium zinc stabilizer for paste; the adhesive is an isocyanate adhesive; The preparation method of a powdered calcium zinc stabilizer for paste comprises: treating zeolite at a temperature not lower than 100° C. for 4-6 minutes to remove moisture from the zeolite; mixing the treated zeolite with a portion of coating-grade zinc stearate at a temperature not lower than 100° C. so that the porous structure and hydroxyl groups on the surface of the zeolite are covered by the coating-grade zinc stearate; then adding the remaining coating-grade zinc stearate, coating-grade calcium stearate, an antioxidant, and a stabilizer; and mixing at a temperature not lower than 25° C. to 45° C. to obtain a powdered calcium zinc stabilizer for paste; mixing is used when treating the zeolite, and the mass ratio of the portion of coating-grade zinc stearate to the zeolite is 1:(5-11); The powdered calcium zinc stabilizer for the paste includes 15%-30% coating-grade zinc stearate, 15%-30% coating-grade calcium stearate, 35%-60% zeolite, 3%-10% antioxidant, and 3%-10% auxiliary stabilizer, wherein the percentages are by mass.

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