WO2020024309A1

WO2020024309A1 - Composite rare earth heat stablizer for pvc and preparation method therefor

Info

Publication number: WO2020024309A1
Application number: PCT/CN2018/099095
Authority: WO
Inventors: 严一丰; 严晴; 周国庆; 高金奎; 蒋设; 肖阳生; 杨光; 范修强; 龙喜香
Original assignee: 深圳市志海实业股份有限公司
Priority date: 2018-07-30
Filing date: 2018-08-07
Publication date: 2020-02-06
Also published as: CN108864619A

Abstract

Provided by the present invention are a composite rare earth heat stabilizer for PVC and a preparation method therefor, and the rare earth composite heat stabilizer comprises the following raw material components in parts by weight: 10-70 parts of rare earth salt; 5-65 parts of calcium stearate; 1-15 parts of an antioxidant; 1-6 parts of hydrotalcite; 1- 4 parts of basic calcium aluminum phosphite; 1-8 parts of stearic acid; 3-10 parts of lauric acid; 5-15 parts of isooctanoic acid; 10-15 parts of polyethylene wax; 0.1-2 parts of phosphite ester; 0.5-5 parts of octyl epoxy stearate; and 2.5-20 parts of di-n-octyl phthalate. The rare earth composite heat stabilizer disclosed by the present invention is an environment-friendly stabilizer with high stability and low price, and has broad application prospects.

Description

Compound rare earth heat stabilizer for PVC and preparation method thereof

Technical field

The invention belongs to the technical field of organic synthesis and material preparation, and particularly relates to a compound type rare earth heat stabilizer for PVC and a preparation method thereof.

Background technique

Polymer material thermal stabilizers are a class of additives that can improve the stability of plastics, films, and fibers during thermoplastic processing, and eliminate or delay the thermal and thermal oxidative degradation of macromolecular chains. Industrially used thermal stabilizers mainly include lead salts, metal soaps, organotin, organic antimony, organic rare earths, hindered amines and hindered phenols of pure organic compounds. Because of its special electronic structure and good coordination ability, rare earth stabilizers have excellent thermal stability, electrical insulation and non-toxic safety, and have become important research and development directions of thermal stabilizers. Rare earth thermal stability additives are mainly used to improve the thermal stability of PVC.

In recent years, the PVC industry has developed rapidly, so PVC heat stabilizers have also become an important industry. To prevent PVC from decomposing during processing, heat stabilizers are essential additives. At present, lead salt stabilizers dominate in China. With the gradual increase of people's awareness of environmental protection, heavy metal salt stabilizers such as lead salts have been gradually eliminated, and non-toxic and efficient compound stabilizers have become a hotspot of research.

According to the thermal decomposition mechanism of polyvinyl chloride, currently the main types of stabilizers are lead salts, metal soaps, organic tin, organic antimony, organic compounds and rare earths. The widely used thermal stabilizers are lead salts and composite metal soaps. And organotin stabilizers. Lead salt heat stabilizers are widely used due to their good thermal stability and low price, but the toxicity of lead salt stabilizers also limits their application. Metal soap stabilizers are mainly calcium-zinc composite heat stabilizers. Calcium-zinc heat stabilizers are widely recognized as non-toxic stabilizers, and their use is gradually increasing. An obstacle. Organotin stabilizers have good thermal stability, but they are expensive and the current output is small. From the perspective of environmental protection and human health, the development direction of PVC heat stabilizers should be non-toxic and efficient compounding.

Rare earth compound heat stabilizer is a new type of PVC heat stabilizer. Rare earth stabilizer is suitable for a variety of PVC products because of its non-toxic, high efficiency, multi-function, and affordable price. China has abundant rare earth resources. It is of great practical significance to make full use of the advantages of our country's rare earth resources to develop a PVC heat stabilizer suitable for China's national conditions.

Research on rare earth compounds as heat stabilizers for polyvinyl chloride has been further deepened. Although it has excellent thermal stability and light and weather resistance, its own thermal stability needs to be further improved. After the auxiliary stabilizer is added, the stability of the rare earth composite thermal stabilizer has been greatly improved. Therefore, the development An environmentally friendly, highly stable, and inexpensive rare earth composite thermal stabilizer has great significance.

Summary of the invention

The technical problem to be solved by the present invention is to provide a rare earth composite PVC thermal stabilizer with environmental protection and outstanding thermal stability in view of the shortcomings in the prior art.

To solve the above problems, the present invention is implemented by the following technical solutions;

A compound type rare earth heat stabilizer for PVC, composed of the following raw materials by weight:

Preferably, the rare earth salt is 20 to 55 parts.

Preferably, the calcium stearate is 20-50 parts.

Preferably, the hydrotalcite is 2 to 5 parts.

Preferably, the basic calcium aluminum phosphite is 2 to 4 parts.

Preferably, the stearic acid is 2-7 parts.

Preferably, the polyethylene wax is 8-15 parts.

Preferably, the polyethylene wax is selected from the group consisting of ethylene homopolymerization products, cracked waxes, and secondary waxes.

Preferably, the stearic acid and the lauric acid are replaced with a mixture of one or more of a mixed fatty acid, oleic acid, naphthenic acid, malic acid, citric acid, adipic acid, and triacetic acid.

Preferably, the mixed fatty acid is a mixture of one or more of an aliphatic monocarboxylic acid and an aliphatic dicarboxylic acid.

Preferably, the aliphatic dicarboxylic acid is an aliphatic dicarboxylic acid containing 6 to 20 carbon atoms and having a linear structure.

Preferably, the phosphite and the octyl epoxy stearate are replaced with one or a mixture of pentaerythritol, dipentaerythritol, trimethylolpropane, and sorbitol.

Preferably, the rare earth salt is rare earth nitrate, rare earth sulfate, or rare earth chloride.

Preferably, the antioxidant is any one of antioxidant 689, antioxidant 264, and antioxidant 1010.

The invention also discloses a method for preparing the above-mentioned composite rare earth heat stabilizer for PVC, including the following steps:

SS1: 1 to 8 parts of stearic acid, 3 to 10 parts of lauric acid, and 5 to 15 parts of isooctanoic acid are mixed into a reaction kettle with a stirrer, stirred, and heated at 80 to 150 ° C for 1 to 3 hour;

SS2: Add 10 to 70 parts of rare earth salts to the reaction kettle, control the ratio of rare earth salts to the acid added to SS1 to 3: 2 to 2: 1, stir and continue heating at 80-150 ° C for 0.5 to 2 hours;

SS3: Add 5 to 65 parts of calcium stearate, 1 to 4 parts of basic calcium aluminum phosphite, and add 0.2 to 5 kg of the catalyst dropwise, and keep it for 1 to 3 hours under stirring to make it uniformly dispersed;

SS4: Continue to add 1 to 15 parts of antioxidant, 1 to 6 parts of hydrotalcite to the reaction kettle to neutralize and absorb HCL generated in the reaction, and add 10 to 15 parts of polyethylene wax as a lubricant, add 0.1 ～ 2 parts of phosphite, 0.5 ～ 5 parts of octyl epoxy stearate, and 2.5 ～ 20 parts of di-n-octyl phthalate, keep stirring for 0.5 ～ 1 hour;

SS5: Stop heating, continue to stir the reaction kettle to cool the product naturally, lower the temperature to 80 ° C, discharge the material, thoroughly cool, grind, screen, and package.

Preferably, the step SS1 specifically refers to adding stearic acid, lauric acid and isooctanoic acid to a three-necked flask, installing a reflux condenser and a heating device, and heating the reaction under the action of magnetic stirring.

Preferably, the catalyst is any one of glacial acetic acid, hydrogen peroxide, and ammonia.

The invention adopts a direct melting synthesis method. The direct melting synthesis method is simple, easy to operate, non-polluting, environmentally friendly, low cost of raw materials, can reduce production costs, and has obvious market competitive advantages. In the formula of the present invention, the proportion of the rare earth salt is excessive, because the excessive rare earth salt can improve the dispersibility of the thermal stabilizer, and the rare earth ion can surface modify the inorganic powder, play a certain coupling agent, and plasticize. Agent and lubricant to improve the mechanical properties of PVC composites.

Compared with the prior art, the present invention has the following advantages:

(1) Excellent thermal stability

Rare earth heat stabilizers have good thermal stability performance, and the comprehensive performance of their compound heat stabilizers is often better than traditional lead salts and barium / zinc, barium / pickle / zinc stabilizers. In some applications, rare earth compound stabilizers It can partially or completely replace organotin.

(2) Good transparency

The refractive index of the rare-earth heat stabilizer is very close to that of the PVC resin, and it can replace the traditionally used organotin for products with higher transparency requirements.

(3) Excellent weather resistance

Rare earth elements can absorb 230-320nm ultraviolet rays (aging factors: ultraviolet rays, oxygen, humidity, etc.). Therefore, rare earth stabilizers have the anti-light aging properties rare in other thermal stabilizers, and are suitable for outdoor products such as PVC corrugated boards and window materials .

(4) Excellent electrical insulation

Some rare earth multifunctional stabilizers can be used instead of lead salt stabilizers for cable compound formulations, and their electrical insulation is comparable to lead salts.

(5) Non-toxic, safe and hygienic

Rare earth elements are low-toxic elements and have no toxic effect on the human body during their production, processing, transportation and storage. Rare earth stabilizers are non-toxic products and can be used in food and pharmaceutical product packaging.

(6) Synergy

There is a significant synergistic effect between rare earth thermal stabilizers and other thermal stabilizers. When they are used in a certain proportion, their long-term thermal stability is significantly improved.

detailed description

The present invention is further described below in conjunction with the examples. It should be understood that the examples are only used to illustrate the present invention, but not to limit the scope of the present invention.

Examples 1-2 are examples of specific formulations and preparation methods of rare earth heat stabilizers for compound PVC. The components and proportions of each raw material in the examples are shown in Table 1. The content of each raw material component in the table is Parts by weight. In order to illustrate the excellent effect of the formulation in the present invention, a comparative example was also added during the test. In Comparative Example 1, no rare earth salt was added, and Comparative Example 2 did not add calcium stearate. The specific formula is shown in Table 1. The contents of each raw material component in the table are parts by weight.

Table 1 Weight proportion of each raw material component in Examples 1 to 2 and Comparative Examples 1 to 2

Example 1

A method for preparing a composite rare earth heat stabilizer for PVC includes the following steps:

SS1: Mix 2 parts of stearic acid, 5 parts of lauric acid, 8 parts of isooctanoic acid into a reaction kettle with a stirrer, stir, and heat at 140 ° C for 2 hours;

SS2: Add 20 parts of rare earth salt to the reaction kettle, stir and continue heating at 140 ° C for 1 hour;

SS3: Add 20 parts of calcium stearate, 2 parts of basic calcium aluminum phosphite, and dropwise add 3kg of catalyst, keep it stirred for 1 hour to make it uniformly dispersed;

SS4: Continue adding 5 parts of antioxidant, 2 parts of hydrotalcite to the reaction kettle to neutralize and absorb the HCL produced in the reaction, and 8 parts of polyethylene wax as a lubricant, 0.5 parts of phosphite and 2 parts of octyl epoxy stearate and 8 parts of di-n-octyl phthalate, stirring continuously for 1 hour;

Example 2

SS1: 7 parts of stearic acid, 8 parts of lauric acid, 13 parts of isooctanoic acid are mixed into a reaction kettle with a stirrer, stirred, and heated at 140 ° C for 2 hours;

SS2: Add 55 parts of rare earth salt to the reaction kettle, stir and continue heating at 140 ° C for 1.5 hours;

SS3: Add 50 parts of calcium stearate, 4 parts of basic calcium aluminum phosphite, and dropwise add 3 kg of catalyst, keep it stirred for 2 hours to make it uniformly dispersed;

SS4: Continue to add 12 parts of antioxidant, 5 parts of hydrotalcite to the reaction kettle to neutralize and absorb HCL produced in the reaction, and add 15 parts of polyethylene wax as lubricant, add 1.5 parts of phosphite and 4 parts of octyl epoxy stearate and 16 parts of di-n-octyl phthalate, stirring continuously for 2 hours;

Comparative Example 1

SS2: Add 20 parts of calcium stearate, 2 parts of basic calcium aluminum phosphite, and dropwise add 3kg of catalyst, keep it stirred for 1 hour to make it uniformly dispersed;

SS3: Continue adding 5 parts of antioxidant, 2 parts of hydrotalcite to the reaction kettle to neutralize and absorb the HCL generated in the reaction, and 8 parts of polyethylene wax as a lubricant, 0.5 parts of phosphite and 2 parts of octyl epoxy stearate and 8 parts of di-n-octyl phthalate, stirring continuously for 1 hour;

SS4: Stop heating, continue to stir the reaction kettle to cool the product naturally, lower the temperature to 80 ° C, discharge the material, thoroughly cool, grind, screen, and package.

Comparative Example 2

SS3: Add 4 parts of basic calcium aluminum phosphite, dropwise add 3kg of catalyst, and keep it for 2 hours under stirring to make it evenly dispersed;

Performance Testing

The performance of the rare-earth composite thermal stabilizer in Examples 1-2 and Comparative Examples 1-2 was tested using the Congo Red test method. Test condition 1 is a static thermal stabilization time test at 180 ° C, and test condition 2 is at The temperature is 180 ° C, and the discoloration time is visually checked. The specific test results are shown in Table 2:

Table 2 Test results

It can be seen from Table 2 that the rare earth salt and calcium stearate have a significant synergistic effect. Adding a mixture of rare earth salt and calcium stearate to PVC to do Congo red static and dynamic test, the stabilization time is significantly longer than using rare earth salt alone In the long, 180 ° C static Congo red experiment, the stabilization time of the rare earth salt alone is about 10 minutes less than that of the composite stabilizer.

The compounded rare earth thermal stabilizer for PVC prepared according to the above-mentioned group distribution ratio and preparation method has excellent stability. The rare earth thermal stabilizer has good thermal stability performance. The overall performance is often better than traditional lead salts and barium / zinc, barium / axle / zinc stabilizers. In some applications, rare earth compound stabilizers can partially or completely replace organotin. Rare earth salts and calcium stearate have obvious synergistic effects. When they are used in a certain proportion, their long-term thermal stability is significantly improved. At the same time, this stabilizer is environmentally friendly, non-toxic and pollution-free.

The above description is only a preferred embodiment of the present invention. Therefore, all equivalent modifications made according to the process principles described in the scope of the patent application of the present invention are included in the scope of the patent application of the present invention.

Claims

A compound type rare earth thermal stabilizer for PVC, characterized in that the rare earth composite thermal stabilizer includes the following raw material components and parts by weight:
The hybrid rare earth heat stabilizer for PVC according to claim 1, characterized in that the rare earth salt is 20 to 55 parts; the calcium stearate is 20 to 50 parts; and the hydrotalcite is 2 to 5 Parts; the basic calcium aluminum phosphite is 2 to 4 parts; the stearic acid is 2 to 7 parts; and the polyethylene wax is 8 to 15 parts.
The compounded rare-earth heat stabilizer for PVC according to claim 2, characterized in that the polyethylene wax is selected from the group consisting of ethylene homopolymerization products, cracked wax, and sub-brand wax.
The rare-earth heat stabilizer for compound PVC according to claim 2, characterized in that: one of mixed fatty acids, oleic acid, naphthenic acid, malic acid, citric acid, adipic acid, and aminotriacetic acid is used, or A mixture of several replaces the stearic acid and the lauric acid.
The hybrid rare earth heat stabilizer for PVC according to claim 2, characterized in that the phosphorous acid is replaced by one or a mixture of pentaerythritol, dipentaerythritol, trimethylolpropane, and sorbitol. Ester and the epoxy octyl stearate.
The hybrid rare earth heat stabilizer for PVC according to claim 2, wherein the rare earth salt is rare earth nitrate, rare earth sulfate, or rare earth chloride.
The compounded rare earth heat stabilizer for PVC according to claim 2, wherein the antioxidant is any one of an antioxidant 689, an antioxidant 264, and an antioxidant 1010.
A method for preparing a composite rare-earth heat stabilizer for PVC according to any one of claims 1 to 7, comprising the following steps:

SS1: Mix 1 to 8 parts of stearic acid, 3 to 10 parts of lauric acid, and 5 to 15 parts of isooctanoic acid into a reaction kettle with a stirrer, stir, and heat the reaction at 80-150 ° C;

SS2: Add 10 to 70 parts of rare earth salts to the reaction kettle, control the ratio of rare earth salts to the acid added to SS1 to 3: 2 to 2: 1, stir and continue to heat the reaction at 80-150 ° C;

SS3: Add 5 to 65 parts of calcium stearate, 1 to 4 parts of basic calcium aluminum phosphite, and add 0.2 to 5 kg of the catalyst dropwise, and keep it for 1 to 3 hours under stirring to make it uniformly dispersed;

SS4: Continue to add 1 to 15 parts of antioxidant, 1 to 6 parts of hydrotalcite to the reaction kettle to neutralize and absorb HCL generated in the reaction, and add 10 to 15 parts of polyethylene wax as a lubricant, add 0.1 ～ 2 parts of phosphite, 0.5 ～ 5 parts of octyl epoxy stearate, and 2.5 ～ 20 parts of di-n-octyl phthalate, keep stirring for 0.5 ～ 1 hour;

SS5: Stop heating, continue to stir the reaction kettle to cool the product naturally, lower the temperature to 80 ° C, discharge the material, thoroughly cool, grind, screen, and package.
The preparation method according to claim 8, wherein the step SS1 specifically comprises adding stearic acid, lauric acid and isooctanoic acid to a three-necked flask, installing a reflux condenser and a heating device, and under the action of magnetic stirring , Heating reaction.
The preparation method according to claim 8, wherein the catalyst is any one of glacial acetic acid, hydrogen peroxide, and ammonia.