Environment-friendly stabilizer for PVC (polyvinyl chloride) and preparation method of environment-friendly stabilizer

Abstract

The invention relates to the field of auxiliary chemicals, in particular to the field of C08L2201 / 08, and particularly relates to an environment-friendly stabilizer for PVC (polyvinyl chloride) and a preparation method of the environment-friendly stabilizer. The environment-friendly stabilizer for PVC is prepared from the following raw materials: stearate, a lubricant, hydrotalcite, an antioxidant, a coupling agent, an auxiliary stabilizer and a filler. Wherein the hydrotalcite comprises CZ-380 and CZ-390, and the lubricant comprises oxidized wax and Fischer-Tropsch wax. The prepared environment-friendly stabilizer for PVC can significantly improve the weather resistance, temperature resistance and glossiness of a PVC product, and the actual use effect is excellent.

Description

Technical Field

[0001] The invention relates to the field of chemical additives, in particular to the field of C08L2201 / 08, and specifically to an environmentally friendly stabilizer for PVC and a preparation method thereof. Background Art

[0002] Stabilizer is a chemical additive that can increase the stability of high molecular plastic polymers. It is used to prevent or slow down the aging of high molecular materials due to external environmental factors during processing, storage and use. Stabilizer can improve the heat resistance of plastics and prevent decomposition during high temperature processing; it can also absorb or shield ultraviolet rays to protect plastics from ultraviolet damage, and has a certain antioxidant effect to prevent plastic products from degradation and discoloration, reduce processing difficulty, and improve production efficiency.

[0003] In the processing of polyvinyl chloride (PVC) resin, adding an appropriate amount of stabilizer can significantly improve the performance and service life of the product. For example, adding a heat stabilizer can prevent the decomposition of PVC resin during the high-temperature plasticization process; adding a light stabilizer can protect the product from ultraviolet damage; adding an antioxidant can extend the antioxidant properties of the product; adding a lubricant can improve the surface smoothness of the product. How to prepare an environmentally friendly stabilizer that can meet the various performance stability requirements of plastic products has high research value.

[0004] Prior art CN108219323A discloses a magnesium-aluminum-zinc environmentally friendly stabilizer specially used for U-PVC extruded transparent pipes, wherein the raw materials include a magnesium-aluminum-zinc composition, hydrotalcite, an antioxidant, zinc stearate, polyethylene wax, oxidized polyethylene wax, etc. The product magnesium-aluminum-zinc environmentally friendly stabilizer has stable chemical properties and will not rust; it has good impact resistance; it has good transparency and wear resistance; however, the inventors found in the actual research and development process that different lubricants have different compatibilities in the stabilizer system, which have a great influence on the performance of the stabilizer, including surface smoothness and stability. Summary of the invention

[0005] In order to solve the above technical problems, the first aspect of the present invention provides an environmentally friendly stabilizer for PVC, the preparation raw materials including: stearate, lubricant, hydrotalcite, antioxidant, coupling agent, auxiliary stabilizer and filler.

[0006] Preferably, the raw materials for preparing the environmentally friendly stabilizer for PVC include, by weight, 20-30 parts of stearate, 10-30 parts of hydrotalcite, 5-10 parts of coupling agent, 1-5 parts of auxiliary stabilizer, 1-3 parts of antioxidant, 20-40 parts of filler, and 1-10 parts of lubricant.

[0007] Further preferably, the raw materials for preparing the environmentally friendly stabilizer include, by weight: 22 parts of stearate, 25 parts of hydrotalcite, 3.8 parts of auxiliary stabilizer, 10 parts of coupling agent, 1 part of antioxidant, 24 parts of filler, and 8 parts of lubricant.

[0008] Stearate

[0009] Preferably, the stearate includes one or more of calcium stearate, zinc stearate, magnesium stearate and aluminum stearate.

[0010] Further preferably, the stearate comprises zinc stearate and calcium stearate, and the mass ratio of the two is (10-20):(5-10); as an implementable case, the mass ratio of zinc stearate to calcium stearate is 15:7.

[0011] Calcium stearate has strong polarity and can form a relatively stable complex system with the chemically active points of PVC resin particles. Its two long-chain alkyl groups have low compatibility with polar resins such as PVC, and form a local microscopic two-phase interface inside the PVC resin, namely a lubricating film. Zinc stearate also has a lubricating effect, which can improve the fluidity and demoulding properties of plastics during plastic processing; when calcium stearate and zinc stearate are compounded, the two can work together in the PVC system to form a more stable and efficient lubrication system, improving the processing performance of plastics; in addition, calcium stearate can capture HCl produced by zinc stearate replacing active chlorine, thereby inhibiting the degradation of PVC; and zinc stearate can act as a main stabilizer to provide the main stabilizing effect. This compound system can not only avoid the "zinc burn" phenomenon when zinc stearate is used alone, but also improve the long-term stability and initial colorability of PVC products.

[0012] Hydrotalcite

[0013] Preferably, the hydrotalcite includes one or more of CZ-280, CZ-380, CZ-390, and CZ-440, all of which are purchased from Shandong Changze New Material Technology Co., Ltd.

[0014] More preferably, the hydrotalcite comprises CZ-380 and CZ-390, and the mass ratio of the two is (10-20):(5-10); as an implementable case, the mass ratio of CZ-380 to CZ-390 is 3:2.

[0015] The inventors found that the type of hydrotalcite has a significant effect on the temperature resistance and smoothness of the environmentally friendly stabilizer. The hydrotalcite CZ-380 can significantly improve the smoothness of the environmentally friendly stabilizer. CZ-380 is alkaline or acid-absorbing; therefore, it can react with acidic substances (such as hydrogen chloride) generated during the degradation of polymer materials such as PVC, thereby inhibiting the degradation process and protecting the smoothness of the material. However, the lubrication performance of CZ-380 is average and the price is relatively expensive. Therefore, adding a certain amount of CZ-390 can improve the lubrication performance of the stabilizer while maintaining the gloss of the environmentally friendly stabilizer, and can also reduce the preparation cost to a certain extent.

[0016] Auxiliary stabilizer

[0017] Preferably, the auxiliary stabilizer comprises dipentaerythritol ester and / or monopentaerythritol ester.

[0018] Further preferably, the auxiliary stabilizer includes dipentaerythritol ester and monopentaerythritol ester, and the mass ratio of the two is (1-1.5):1; as an implementable case, the mass ratio of dipentaerythritol ester to monopentaerythritol ester is 10:9.

[0019] As an auxiliary stabilizer for PVC, monopentaerythritol ester can effectively improve the thermal stability of PVC, inhibit the degradation process at high temperature, and can produce a synergistic effect when used in combination with calcium stearate and zinc stearate, inhibiting the "zinc burning" phenomenon, thereby obtaining better long-term thermal stability; dipentaerythritol ester also has good thermal stability, but it has better thermal stability than monopentaerythritol ester. The addition of dipentaerythritol ester may have a certain impact on the transparency of PVC products, especially in the case of high addition; in contrast, the effect of monopentaerythritol ester on transparency may be smaller. Therefore, the combination of the two can ensure the thermal stability of PVC without affecting the smoothness of the material.

[0020] Coupling agent

[0021] Preferably, the coupling agent includes: one or more of an aluminate coupling agent, a silane coupling agent, and a titanate coupling agent.

[0022] More preferably, the coupling agent is an aluminate coupling agent.

[0023] Lubricants

[0024] Preferably, the lubricant comprises: one or more of oxidized wax, Fischer-Tropsch wax, and polyethylene wax.

[0025] Further preferably, the lubricant comprises oxidized wax and Fischer-Tropsch wax, and the mass ratio of the two is 1:(5-10); as an implementable case, the mass ratio of the oxidized wax to the Fischer-Tropsch wax is 1:7.

[0026] In the present invention, oxidized wax and Fischer-Tropsch wax are preferably compounded as lubricants, which can significantly improve the surface gloss of the environmentally friendly stabilizer and help improve the strength and toughness of the stabilizer as well as the processing efficiency. However, for other lubricants such as polyethylene wax, since PVC is a polar polymer, and polyethylene wax is mainly polymerized from non-polar ethylene units, there is a difference in polarity between the two; at the same time, polyethylene wax has a higher crystallinity, while PVC has a relatively low crystallinity. Due to the dual differences in crystallinity and polarity, the mixing uniformity and compatibility of polyethylene wax in the environmentally friendly stabilizer for PVC will be affected, thereby affecting the surface finish of the PVC material.

[0027] Antioxidants

[0028] The antioxidant is not further limited in the present invention. Any auxiliary agent that can delay or prevent the oxidation process of the environmentally friendly stabilizer can be used, including but not limited to: one of antioxidant 1010, antioxidant 168, antioxidant 1076, antioxidant 618, and antioxidant 1098.

[0029] Fillers

[0030] Preferably, the filler includes light calcium carbonate and / or heavy calcium carbonate.

[0031] Light calcium carbonate has a smaller particle size and better dispersibility. Smaller particle size means that it can be more evenly distributed in PVC resin, which can improve the stability of the product, thus helping to improve the processing performance of PVC materials and the performance of the final product. In contrast, heavy calcium carbonate has a larger particle size and is not as dispersible as light calcium carbonate. It is easy to agglomerate during processing, affecting the quality of the product; at the same time, the bulk density of light calcium carbonate is smaller, while the bulk density of heavy calcium carbonate is larger. At the same filling amount, light calcium carbonate can occupy more volume, thereby more effectively reducing the density of PVC materials and increasing the scope of use of the product.

[0032] The second aspect of the present invention provides a method for preparing an environmentally friendly stabilizer, comprising: mixing the raw materials for preparation, and cold-refining the mixture into sheets through a double-roll mill.

[0033] Beneficial Effects

[0034] (1) The environmentally friendly stabilizer prepared by the present invention is relatively green and environmentally friendly, and the raw materials do not contain heavy metal elements such as lead / separation, etc., and can meet the requirements of the latest environmental protection standards of various countries (such as the EU RHOS Directive, REACH Directive, etc.).

[0035] (2) The raw materials for preparing the environmentally friendly stabilizer in the present invention include calcium stearate and zinc stearate. When used in the field of PVC processing, the product using the composite lead heat stabilizer is easily contaminated by sulfur and tin and turns black. The environmentally friendly stabilizer of the calcium-zinc system of the present invention will not be affected by this.

[0036] (3) The present invention uses a specific hydrotalcite, which can further improve the product's finish while ensuring the excellent weather resistance of the environmentally friendly stabilizer.

[0037] (4) The environmentally friendly stabilizer provided by the present invention can give the PVC mixture good uniform plasticization and high-speed melt fluidity, making the surface of the product brighter and free of impurities, with high weather resistance and a wide range of applications; in white products, the whiteness is better than that of similar products.

[0038] (5) The environmentally friendly stabilizer provided by the present invention has good lubricity and unique coupling effect, which can improve the comprehensive performance of PVC products, reduce mechanical wear, and extend the service life of equipment; due to the balanced lubrication of its various component raw materials, the environmentally friendly stabilizer provided by the present invention can significantly increase the service life of PVC products. DETAILED DESCRIPTION

[0039] The manufacturers and model information of the following raw materials in the present invention are as follows:

[0040] The model of zinc stearate is Zhongshan Huamingtai BT-2818; zinc stearate can also be purchased from Anhui Ruihua.

[0041] The model of calcium stearate is Zhongshan Huamingtai BS-3818; calcium stearate can also be purchased from Jinqiao Technology or Anhui Ruihua.

[0042] The model of Fischer-Tropsch wax is Ningmei Chemical 40.

[0043] The oxidized wax model is Ningmei Chemical N105.

[0044] CZ-380 was purchased from Shandong Changze New Materials.

[0045] CZ-390 was purchased from Shandong Changze New Materials.

[0046] CZ-440 was purchased from Shandong Changze New Materials.

[0047] Antioxidant 1010 was purchased from Shenzhen Yu's Chemical.

[0048] The model of aluminate coupling agent is Nanjing Herun GR-AL18.

[0049] The model of dipentaerythritol ester is Tianjin Jinheng Blue Ocean JH220.

[0050] The model of monopentaerythritol ester is Jiangsu Haian PETS-1.

[0051] The model of light calcium carbonate is Jiangxi Guangyuan calcium powder GY-816.

[0052] The specification of the polyethylene wax is not particularly limited, and any commercially available one may be used.

[0053] Example 1

[0054] The first aspect of this example provides an environmentally friendly stabilizer for PVC. The raw materials for its preparation include, by weight: 22 parts of stearate, 25 parts of hydrotalcite, 3.8 parts of auxiliary stabilizer, 1 part of antioxidant, 24 parts of filler, 8 parts of lubricant, and 10 parts of coupling agent.

[0055] The stearate comprises zinc stearate and calcium stearate in a mass ratio of 15:7.

[0056] The lubricant is oxidized wax and Fischer-Tropsch wax, with a mass ratio of 1:7.

[0057] The hydrotalcite is CZ-380 and CZ-390, with a mass ratio of 3:2.

[0058] The auxiliary stabilizer is dipentaerythritol ester and monopentaerythritol ester, and the mass ratio is 10:9.

[0059] The coupling agent is an aluminate coupling agent.

[0060] The antioxidant is antioxidant 1010.

[0061] The filler is light calcium carbonate.

[0062] The second aspect of this example provides a method for preparing an environmentally friendly stabilizer for PVC, comprising: mixing the raw materials for preparing the environmentally friendly stabilizer, and cold-refining it into sheets through a double-roll mill.

[0063] Example 2

[0064] The first aspect of this example provides an environmentally friendly stabilizer for PVC. The raw materials for its preparation include, by weight: 22 parts of stearate, 25 parts of hydrotalcite, 3.8 parts of auxiliary stabilizer, 1 part of antioxidant, 24 parts of filler, 8 parts of lubricant, and 10 parts of coupling agent.

[0065] The stearate comprises zinc stearate and calcium stearate in a mass ratio of 15:7.

[0066] The lubricant is oxidized wax and Fischer-Tropsch wax, with a mass ratio of 1:7.

[0067] The hydrotalcite is CZ-380.

[0068] The auxiliary stabilizer is dipentaerythritol ester and monopentaerythritol ester, and the mass ratio is 10:9.

[0069] The coupling agent is an aluminate coupling agent.

[0070] The antioxidant is antioxidant 1010.

[0071] The filler is light calcium carbonate.

[0072] The second aspect of this example provides a method for preparing an environmentally friendly stabilizer for PVC, comprising: mixing the raw materials for preparing the environmentally friendly stabilizer, and cold-refining it into sheets through a double-roll mill.

[0073] Example 3

[0074] The first aspect of this example provides an environmentally friendly stabilizer for PVC. The raw materials for its preparation include, by weight: 22 parts of stearate, 25 parts of hydrotalcite, 3.8 parts of auxiliary stabilizer, 1 part of antioxidant, 24 parts of filler, 8 parts of lubricant, and 10 parts of coupling agent.

[0075] The stearate comprises zinc stearate and calcium stearate in a mass ratio of 15:7.

[0076] The lubricant is oxidized wax and polyethylene wax, and the mass ratio is 1:7.

[0077] The hydrotalcite is CZ-380 and CZ-390, with a mass ratio of 3:2.

[0078] The auxiliary stabilizer is dipentaerythritol ester and monopentaerythritol ester, and the mass ratio is 10:9.

[0079] The coupling agent is an aluminate coupling agent.

[0080] The antioxidant is antioxidant 1010.

[0081] The filler is light calcium carbonate.

[0082] The second aspect of this example provides a method for preparing an environmentally friendly stabilizer for PVC, comprising: mixing the raw materials for preparing the environmentally friendly stabilizer, and cold-refining it into sheets through a double-roll mill.

[0083] Example 4

[0084] The first aspect of this example provides an environmentally friendly stabilizer for PVC. The raw materials for its preparation include, by weight: 22 parts of stearate, 25 parts of hydrotalcite, 3.8 parts of auxiliary stabilizer, 1 part of antioxidant, 24 parts of filler, 8 parts of lubricant, and 10 parts of coupling agent.

[0085] The stearate comprises zinc stearate and calcium stearate in a mass ratio of 15:7.

[0086] The lubricant is oxidized wax and Fischer-Tropsch wax, with a mass ratio of 1:7.

[0087] The hydrotalcite is CZ-440.

[0088] The auxiliary stabilizer is dipentaerythritol ester and monopentaerythritol ester, and the mass ratio is 10:9.

[0089] The coupling agent is an aluminate coupling agent.

[0090] The antioxidant is antioxidant 1010.

[0091] The filler is light calcium carbonate.

[0092] The second aspect of this example provides a method for preparing an environmentally friendly stabilizer for PVC, comprising: mixing the raw materials for preparing the environmentally friendly stabilizer, and cold-refining it into sheets through a double-roll mill.

[0093] Performance Evaluation

[0094] Test object: environmentally friendly stabilizer obtained in Examples 1-4.

[0095] Test method: Place the environmentally friendly stabilizer in a 180°C high-temperature oven and observe the weather resistance, temperature resistance and smoothness after 10 minutes. The test results are detailed in Table 1.

[0096] If the product has no color change, the weather resistance is recorded as excellent, otherwise it is recorded as fair.

[0097] If there is no blistering on the surface, the temperature resistance is recorded as excellent, otherwise it is recorded as fair.

[0098] If the surface gloss has no obvious dull spots, the finish is recorded as excellent, otherwise it is recorded as fair.

[0099] Table 1

[0100] Weather resistance Temperature resistance Finish Example 1 excellent excellent excellent Example 2 excellent generally generally Example 3 excellent excellent generally Example 4 excellent generally generally

Claims

1. An environmentally friendly stabilizer for PVC, characterized in that: The preparation raw materials include: stearate, lubricant, hydrotalcite, antioxidant, coupling agent, auxiliary stabilizer and filler.

2. The environmentally friendly stabilizer for PVC according to claim 1, characterized in that: The raw materials for preparing the environmentally friendly stabilizer for PVC include, by weight, 20-30 parts of stearate, 10-30 parts of hydrotalcite, 5-10 parts of coupling agent, 1-5 parts of auxiliary stabilizer, 1-3 parts of antioxidant, 20-40 parts of filler and 1-10 parts of lubricant.

3. The environmentally friendly stabilizer for PVC according to claim 1, characterized in that: The stearate includes one or more of calcium stearate, zinc stearate, magnesium stearate and aluminum stearate.

4. The environmentally friendly stabilizer for PVC according to claim 3, characterized in that: The stearate comprises zinc stearate and calcium stearate, and the mass ratio of zinc stearate to calcium stearate is (10-20):(5-10).

5. The environmentally friendly stabilizer for PVC according to claim 1, characterized in that: The hydrotalcite includes one or more of CZ-280, CZ-380, CZ-390 and CZ-440.

6. The environmentally friendly stabilizer for PVC according to claim 5, characterized in that: The hydrotalcite comprises CZ-380 and CZ-390; the mass ratio of CZ-380 to CZ-390 is (10-20):(5-10).

7. The environmentally friendly stabilizer for PVC according to claim 1, characterized in that: The auxiliary stabilizer includes: dipentaerythritol ester and / or monopentaerythritol ester.

8. The environmentally friendly stabilizer for PVC according to any one of claims 1 to 7, characterized in that: The filler includes: light calcium carbonate and / or heavy calcium carbonate.

9. The environmentally friendly stabilizer for PVC according to claim 1, characterized in that: The lubricant includes: one or more of oxidized wax, Fischer-Tropsch wax and polyethylene wax.

10. A method for preparing an environmentally friendly stabilizer for PVC according to any one of claims 1 to 9, characterized in that: include: The prepared raw materials are mixed and cold-refined into sheets by a double-roll mill to obtain the product.