Barium-cadmium-zinc liquid stabilizer and preparation method thereof

Abstract

The barium-cadmium-zinc liquid stabilizer is prepared from the following raw materials in parts by weight: 0.5 to 12 parts of barium oleate, 1.5 to 15 parts of a zinc source, 10 to 60 parts of organic acid, 10 to 40 parts of a cadmium source, 15 to 100 parts of a solvent, 0.5 to 4.5 parts of an antioxidant, 4 to 18 parts of a membrane surface precipitation resisting agent, 1.5 to 4.5 parts of a phosphite ester precipitation resisting agent, 1 to 15 parts of phosphite ester and 5 to 20 parts of POSS-OH, the preparation method comprises the following steps: S101, mixing gamma-aminopropyltriethoxysilane and glycerol, adding into methanol, dissolving, and S102, slowly adding hydrofluoric acid, reacting for 3-6 hours, and drying to obtain POSS-OH.

Description

Technical Field

[0001] The present invention relates to the field of heat stabilizers for polyvinyl chloride (PVC), and particularly to a barium-cadmium-zinc liquid stabilizer and a preparation method thereof. Background Art

[0002] As one of the five general-purpose plastics, PVC has been widely used in many fields such as construction, packaging, electronics, electrical appliances, and medical due to its good physical properties, chemical stability, processability, and relatively low cost. However, PVC itself has some inherent defects, and it has a poor thermal stability problem during processing and use. During the processing, PVC usually needs to go through steps such as high-temperature melting, mixing, and forming. When the temperature rises to a certain degree (generally around 100°C - 200°C), the PVC molecular chain is prone to dehydrochlorination reaction, which in turn causes the PVC material to change color, deteriorate in performance, and even decompose, seriously affecting the quality and appearance of PVC products.

[0003] To solve the thermal stability problem of PVC, a heat stabilizer must be added during the PVC processing. The heat stabilizer can effectively inhibit the thermal degradation process of PVC through various action mechanisms such as absorbing hydrogen chloride gas generated by PVC decomposition, replacing unstable chlorine atoms on the PVC molecular chain, and reacting with free radicals generated by PVC degradation, thereby ensuring the stability of PVC products during processing and use.

[0004] The high-alkali barium liquid stabilizer is a special type of metal soap stabilizer. It has some unique advantages compared with traditional barium soap stabilizers. It can further improve the thermal stability effect of PVC, improve fluidity, and improve transparency, etc. However, currently adding high-alkali barium to the stabilizer will affect the dynamic initial coloring of PVC. Therefore, it is necessary to improve the liquid stabilizer added with high-alkali barium to solve the problem of dynamic initial coloring, so that the low-cost barium-cadmium-zinc liquid stabilizer can be better applied and promoted.

[0005] Through chemical modification, POSS materials with polar groups can interact with metal ions in liquid stabilizers. This interaction changes the active state of the metal ions, weakening their catalytic degradation effect on the initial degradation of PVC. Moreover, the free radicals generated during the initial stage of PVC processing can also be captured and removed by the inorganic framework (Si-O-Si) in the POSS material. The lone pair electrons on the oxygen atoms in the Si-O-Si bond can react with the free radicals, converting the free radicals into relatively stable substances, thus interrupting the PVC degradation reaction chain initiated by free radicals and reducing the coloring problems caused by degradation. At the same time, the molecular size of the POSS material is at the nanometer level. When added to the liquid stabilizer, its relatively large molecular structure can generate steric hindrance between the PVC chains. This steric hindrance can prevent the PVC molecular chains from approaching too closely, reducing the chance of contact between metal ions and unstable chlorine atoms on the PVC molecular chains.

[0006] The Chinese patent with publication number CN113372614A discloses a barium-cadmium-zinc composite stabilizer and its preparation, which is prepared from cadmium fatty acid, barium fatty acid, solvent oil, zinc fatty acid, pentaerythritol, phosphite, and antioxidant.

[0007] The Chinese patent with publication number CN109082125A discloses a high-alkali barium stabilizer for PVC and its preparation method. The heat stabilizer is composed of the following raw materials in mass percentages: 30-40% of calcium glycerol pentenate composition; 20-30% of barium laurate; 3-8% of montmorillonite; 8-12% of covalent organic framework; 3-8% of lubricant; 4-9% of epoxy plasticizer; 6-10% of β-diketone. The covalent organic framework adopted in the present invention is extended to form a network structure through covalent bonds, having a large BET value. Its high specific surface area enables it to have an enrichment effect, a large adsorption capacity, significantly improving the thermal stability during the PVC processing and reducing the problem of initial coloring; the preparation method of the heat stabilizer provided by the present invention is simple, easy to operate, environmentally friendly, and the prepared heat stabilizer has good thermal stability and processability.

[0008] The Chinese patent with the publication number CN117801525B discloses a high-performance composite heat stabilizer, which is characterized by including the following components in parts by mass: 20 - 50 parts of a main stabilizer, 1 - 5 parts of an auxiliary stabilizer, 1 - 5 parts of an ultraviolet absorber, 1 - 15 parts of modified silica, 3 - 9 parts of a foaming agent, 20 - 25 parts of a foaming stabilizer, and 1 - 7 parts of a filler; the main stabilizer is a mixture of calcium rosinate and zinc citrate; the molar ratio of calcium rosinate to zinc citrate is 1:(0.8 - 1.2); the mass ratio of the main stabilizer to the auxiliary stabilizer is 1:(0.07 - 0.09); the mass ratio of the main stabilizer to the modified silica is 1:(0.15 - 0.25); the modified silica is octa(epoxycyclohexyl)ethyl POSS-modified silica. The octa(epoxycyclohexyl)ethyl POSS molecule has a large steric hindrance and strong polarity, while most PVC liquid stabilizers are non-polar or weakly polar substances. According to the principle of like dissolves like, it is difficult to dissolve in PVC liquid stabilizers. Liquid PVC stabilizers usually use organic solvents (such as phthalate esters, cyclohexanone, etc.) as carriers, and the epoxy groups of octa(epoxycyclohexyl)ethyl POSS have a relatively high polarity and poor compatibility with conventional solvents, which easily leads to system stratification or precipitation.

[0009] The Chinese patent with the publication number CN118271837A discloses a compound stabilizer for PBAT polymerization and its preparation method. A compound stabilizer for PBAT polymerization includes the following raw materials in parts by weight: 2 - 4 parts of intercalated modified hydrotalcite, 1 - 2 parts of polycarbodiimide, 1 - 2 parts of pentaerythritol, 1.5 - 3 parts of modified halloysite nanotubes, and 1 - 2 parts of amino-functionalized cage-shaped polyhedral oligomeric silsesquioxane; its preparation method is: mixing the intercalated modified hydrotalcite, polycarbodiimide, pentaerythritol, modified halloysite nanotubes, and amino-functionalized cage-shaped polyhedral oligomeric silsesquioxane evenly to obtain the compound stabilizer. Since hydrogen bonds are prone to agglomeration, it cannot be used in liquid stabilizers either. The amino functional groups of NH2-POSS have a relatively high polarity and poor compatibility with non-polar or weakly polar solvents (such as phthalate esters) commonly used in liquid PVC stabilizers, which easily leads to phase separation or precipitation 57. Its cage structure is difficult to disperse evenly under low shear force conditions, affecting the uniformity of the stabilizer system.

[0010] In the prior art, POSS cannot be applied in barium-cadmium-zinc liquid stabilizers. Summary of the Invention

[0011] The object of the present invention is to overcome the problem of poor initial coloring when using existing high-alkali barium liquid stabilizers, and provide a barium-cadmium-zinc liquid stabilizer and its preparation method.

[0012] To achieve the above object, the present invention adopts the following technical solutions:

[0013] The POSS-OH added in the formulation of the present invention is chemically modified and has polar groups, which can effectively solve the problem of poor compatibility of POSS in the PVC system.

[0014] POSS-(OH) is added to the formulation of the present invention. Through chemical modification, the POSS material with polar groups can interact with metal ions in the liquid stabilizer. This interaction will change the active state of the metal ions, weakening their catalytic degradation effect on the initial degradation of PVC. Moreover, the free radicals generated during the initial stage of PVC processing will also be captured and removed by the inorganic skeleton (Si-O-Si) in the POSS material. The lone pair electrons on the oxygen atoms in the Si-O-Si bond can react with the free radicals, converting the free radicals into relatively stable substances, thereby interrupting the PVC degradation reaction chain initiated by free radicals and reducing the coloring problem caused by degradation. At the same time, the molecular size of the POSS material is at the nanometer level. When added to the liquid stabilizer, its relatively large molecular structure can generate steric hindrance between the PVC chains. This steric hindrance can prevent the PVC molecular chains from approaching too closely, reducing the contact opportunity between metal ions and the unstable chlorine atoms on the PVC molecular chains and solving the initial coloring problem.

[0015] Cadmium metal is added to the formulation of the present invention. During the processing of PVC, cadmium can react with the hydrogen chloride generated by the decomposition of PVC, slowing down the thermal degradation rate of PVC and improving thermal stability. It can effectively inhibit the discoloration phenomenon of PVC in the initial stage of processing, cooperate with barium and zinc, play a synergistic stabilizing role, and reduce the dosage of the stabilizer. Cadmium can replace unstable chlorine atoms, neutralize hydrogen chloride and regenerate stable substances. And the preparation method of the liquid stabilizer provided by the present invention is simple, the operation is convenient, and the prepared liquid stabilizer has good thermal stability, initial coloring and processability.

[0016] Synergistic thermal stabilization effect of barium oleate and zinc source: Barium (Ba 2 +) provides long-term thermal stability and inhibits the HCl elimination reaction of PVC; zinc (Zn2+) enhances the initial thermal stability and prevents yellowing in the initial stage of processing. Metal coordination regulation: Through organic acid salts such as barium / zinc isooctanoate, dynamic coordination bonds are formed with PVC chain segments to delay the degradation process.

[0017] Organic acids as metal ion chelating agents: form stable complexes with barium and zinc ions, improving dispersibility and system compatibility. Lubrication auxiliary function: reduce the melt friction coefficient, reduce processing energy consumption, and adapt to processes such as calendering and extrusion. Solvents ensure the fluidity and storage stability of the liquid stabilizer. Antioxidant inhibition of oxidative degradation: Phenolic or phosphite antioxidants block the free radical chain reaction and prevent the mechanical properties of the material from deteriorating due to thermal oxidation

[0018] Anti-film surface precipitation agent: The long-chain fatty acid derivative migrates to the surface to form a physical barrier, reducing the migration of stabilizers to the product surface. The phosphite anti-precipitation agent adsorbs on the PVC molecular chain through polar groups, reducing the interfacial tension and inhibiting the precipitation tendency.

[0019] During the processing of PVC, cadmium can react with hydrogen chloride generated by the decomposition of PVC, slowing down the thermal degradation rate of PVC and improving thermal stability. It can effectively inhibit the discoloration phenomenon of PVC at the initial stage of processing, cooperate with barium and zinc, play a synergistic stabilizing role, and reduce the dosage of stabilizers. Cadmium can replace unstable chlorine atoms, neutralize hydrogen chloride, and regenerate stable substances.

[0020] The transparency and thermal stability of the barium-cadmium-zinc liquid stabilizer added with barium oleate have been greatly improved. Description of the Drawings

[0021] Figure 1 The following shows the composition performance table of the first group of embodiments of the present invention.

[0022] Figure 2 The following shows the composition performance table of the second group of embodiments of the present invention. Detailed Description of the Invention

[0023] Now, the present invention will be further described in detail with reference to the embodiments.

[0024] In this application, the anti-film surface precipitation agent is represented by MX in the table, the phosphite anti-precipitation agent is represented by YX, the dynamic stability (min) is represented by DT, the static stability is represented by JT, the initial haze is represented by WW, and POSS-OH is represented by POH.

[0025] Please refer to Table 1

[0026] A preparation method for preparing a barium-cadmium-zinc liquid stabilizer specifically includes the following steps:

[0027] (1) Mix barium oleate, cadmium source, zinc source, organic acid, and solvent and stir. After heating to 80 °C and holding for half an hour, successively add phosphite, antioxidant, anti-film surface precipitation agent, and phosphite anti-precipitation agent, and then stir and react for half an hour.

[0028] (2) After heating the solution in step (1) to 95 °C, add POSS (if any), mix and stir for 10 - 40 minutes, and then cool to room temperature to obtain the barium-cadmium-zinc liquid stabilizer.

[0029] Table 1 shows that there are solubility problems in introducing POSS into the barium-cadmium-zinc liquid stabilizer.

[0030]

[0031] Table 1 Composition Table of Comparative Examples

[0032] Examples 1 - 46, barium source: barium oleate, cadmium source: cadmium oleate, zinc source: zinc oleate, organic acid: oleic acid, solvent: mineral oil, phosphite: phenyl diisooctyl phosphite, antioxidant: antioxidant 1010, anti - surface precipitation agent MX: pentaerythritol, phosphite anti - precipitation agent YX: hydrolyzed phenyl diisooctyl phosphite.

[0033] Please refer to Figure 1 , the component performance table of the first group of examples of the present invention.

[0034] Mix γ - aminopropyltriethoxysilane and glycerol with a molar ratio of 1:2. Then add the product to 100 mL of methanol for dissolution, and then slowly add 2 - 5% hydrofluoric acid, react for 3 - 6 hours, and finally dry in vacuum to obtain POSS-(OH).

[0035] A preparation method of barium - cadmium - zinc liquid stabilizer, specifically including the following steps:

[0036] (1) Mix barium oleate, cadmium source, zinc source, organic acid and solvent and stir. After heating to 80 °C and holding for half an hour, successively add phosphite, antioxidant, anti - surface precipitation agent, and phosphite anti - precipitation agent, and then stir and react for half an hour.

[0037] (2) After heating the solution in step (1) to 95 °C, add POSS-(OH), mix and stir for 10 - 40 minutes, and then cool to room temperature to obtain the barium - cadmium - zinc liquid stabilizer.

[0038] A preparation method of barium - cadmium - zinc liquid stabilizer, specifically including the following steps:

[0039] (1) Mix barium oleate, cadmium source, zinc source, organic acid and solvent and stir. After heating to 80 °C and holding for half an hour, successively add phosphite, antioxidant, anti - surface precipitation agent, and phosphite anti - precipitation agent, and then stir and react for half an hour.

[0040] (2) After heating the solution in step (1) to 95 °C, add POSS-(OH), mix and stir for 10 - 40 minutes, and then cool to room temperature to obtain the barium - cadmium - zinc liquid stabilizer.

[0041] Performance test:

[0042] The raw materials used for the PVC sample are as follows:

[0043] 100 parts by mass of PVC resin;

[0044] 30 parts by mass of dioctyl phthalate (DOP);

[0045] 2 - 3 parts by mass of barium - cadmium - zinc liquid stabilizer;

[0046] After adding PVC resin and the barium-cadmium-zinc liquid stabilizers prepared in this example and the comparative example into a plasticizer and mixing them at high speed, they were kneaded on a two-roll mill, then plasticized, sheeted, sliced, and cut into small pieces of 5 mm × 5 mm to obtain PVC specimens for static testing.

[0047] After adding PVC resin and the barium-cadmium-zinc liquid stabilizers prepared in this example and the comparative example into a plasticizer and mixing them at high speed, they were kneaded on a two-roll mill, and then samples were taken and sliced every five minutes during plasticization to obtain PVC specimens for dynamic and haze tests.

[0048] Please refer to Figure 2 , the composition performance table of the second group of examples of the present invention

[0049] For the second group of examples of the present invention, the anti-film surface precipitant is selected as a high molecular polyester compound (polyester amide), and the rest remains unchanged.

[0050] Analysis

[0051] In Examples 1-6, as POSS-OH gradually increased, the dynamic stability first increased and then decreased, the initial haze first decreased and then increased, and the static stability first increased and then decreased.

[0052] In Examples 7-10, 17-19, 39-43, as barium oleate gradually increased, both the dynamic stability and the static stability gradually increased, and the initial haze (%) gradually decreased.

[0053] In Examples 11-15, 43-47, as the cadmium source gradually increased, both the dynamic stability and the static stability gradually increased, and the initial haze (%) gradually decreased.

[0054] In Examples 20-21, as the zinc source gradually increased, both the dynamic stability and the static stability gradually decreased, and the initial haze (%) gradually decreased.

[0055] In Examples 23-24, as the organic acid increased, both the dynamic stability and the static stability gradually increased, and the initial haze (%) gradually decreased.

[0056] In Examples 24-26, there was no obvious change in performance after the increase of phosphite. In Examples 26-31, there was no obvious change in performance after the increase of antioxidant. In Examples 32-34, there was no obvious change in performance after the increase of the anti-film surface precipitant. In Examples 31, 35-38, there was no obvious change in performance after the increase of the phosphite anti-precipitant.

[0057] Taking the ideal embodiments of the present invention described above as an inspiration, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A barium-cadmium-zinc liquid stabilizer, comprising the following raw materials in parts by weight: 0.5-12 parts of barium oleate, 1.5-15 parts of zinc source, 10-60 parts of organic acid, 10-40 parts of cadmium source, 0.5-4.5 parts of antioxidant, 4-18 parts of anti-film surface precipitation agent, 1.5-4.5 parts of phosphite anti-precipitation agent, 1-15 parts of phosphite, 0-100 parts of solvent, characterized in that, It also includes 5-20 parts of POSS-OH, which is prepared by the following method: S101 Mix γ-aminopropyltriethoxysilane and glycerol and then dissolve them in methanol. S102 Slowly add hydrofluoric acid, and after reacting for 3-6 hours, dry to obtain POSS-OH.

2. The barium-cadmium-zinc liquid stabilizer according to claim 1, wherein, The molar ratio of the γ-aminopropyltriethoxysilane to the glycerol is 1:

2.

3. The barium-cadmium-zinc liquid stabilizer according to claim 2, wherein It also includes: The phosphite anti-bleeding agent is selected from one or more of antioxidant Y-211, antioxidant Y-450, triphenyl phosphite, diphenyl octyl phosphite, and tris(nonylphenyl) phosphite.

4. The barium-cadmium-zinc liquid stabilizer according to claim 3, characterized in that, It also includes: The cadmium source is selected from cadmium stearate, cadmium laurate, and cadmium oleate.

5. The barium-cadmium-zinc liquid stabilizer according to claim 4, characterized in that: The organic acid is a fatty acid or the organic acid is selected from one or more of stearic acid, oleic acid, isooctanoic acid, octanoic acid, maleic acid, phthalic acid, benzoic acid, salicylic acid, citric acid, and tartaric acid.

6. The barium-cadmium-zinc liquid stabilizer according to claim 5, wherein: The solvent is selected from one or more of dioctyl phthalate, diisooctyl phthalate, poly(propylene adipate), poly(butylene terephthalate), epoxidized soybean oil, butyl epoxystearate, chlorinated paraffin, and mineral oil.

7. The barium-cadmium-zinc liquid stabilizer according to claim 6, characterized in that: The phosphite is selected from one or more of triphenyl phosphite, diphenyl octyl phosphite, diphenyl decyl phosphite, and tris(nonylphenyl) phosphite.

8. The barium-cadmium-zinc liquid stabilizer according to claim 7, wherein: The antioxidant is selected from one or more of antioxidant 1010, antioxidant 264, antioxidant 168, antioxidant 626, and antioxidant DLTP.

9. The barium-cadmium-zinc liquid stabilizer according to claim 8, wherein: The anti-film bleeding agent is selected from one or more of calcium stearate, hydrotalcite compounds, high molecular polyester compounds, and silicone compounds; The zinc source is selected from one or more of zinc 2-ethylhexanoate, zinc laurate, zinc naphthenate, zinc octanoate, benzoic acid and substituted benzoic acid zinc, and zinc oleate.

10. A method for preparing the barium-cadmium-zinc liquid stabilizer according to any one of claims 1-9, characterized in that It includes the following steps: (1) Mix barium oleate, zinc source, cadmium source, organic acid, and solvent and stir. Heat up to 75-85 °C and keep warm for half an hour, then successively add phosphite, antioxidant, anti-film bleeding agent, and phosphite anti-bleeding agent, and stir and react sufficiently; (2) Heat up the solution in step (1) to 90-95 °C, add POSS-(OH), mix and stir sufficiently, and then cool to room temperature to obtain the barium-cadmium-zinc liquid stabilizer.

Images