Preparation method and application of liquid fatty acid barium heat stabilizer monomer with long shelf life

Abstract

The invention relates to the technical field of compound purification and organic ingredients, in particular to a preparation method and application of a liquid fatty acid barium heat stabilizer monomer with a long shelf life. The mixed acid and barium hydroxide monohydrate which is purified through acid pickling, adsorption filtration, double decomposition reaction, adsorption filtration and concentration recrystallization are subjected to acid-base neutralization in an organic solvent and react in a circulating reactor to obtain a liquid fatty acid barium heat stabilizer monomer with a long shelf life, and the liquid fatty acid barium heat stabilizer monomer can be applied to compounding of PVC heat stabilizers. The shelf life of the fatty acid barium heat stabilizer monomer produced by the method disclosed by the invention is up to 10-16 months, no turbid phenomenon occurs, and the fatty acid barium heat stabilizer monomer is still kept in a transparent liquid state; the fatty acid barium heat stabilizer monomer is compounded for use after being stored for more than 10 months, and the effect of the fatty acid barium heat stabilizer monomer is equal to that of a fatty acid barium heat stabilizer compound product within 2 months after leaving a factory.

Description

Technical Field

[0001] The present invention relates to the technical fields of compound purification and organic ingredients, and particularly relates to a preparation method and application of a liquid barium fatty acid heat stabilizer monomer with a long shelf life. Background Art

[0002] Liquid barium fatty acid heat stabilizer is a fatty acid barium monomer in a compounded barium-cadmium-zinc heat stabilizer commonly used in plastic processing such as polyvinyl chloride (PVC). The liquid barium fatty acid stabilizer monomer is mainly prepared by the acid-base neutralization reaction of mixed acids such as stearic acid, octanoic acid, and oleic acid with barium-containing basic compounds at high temperature. Barium fatty acid is mainly used to improve the stability of materials during high-temperature processing, provide long-term heat stability, and can effectively inhibit hydrogen chloride (HCl) generated by thermal decomposition of plastics such as PVC during processing, delay material aging, and prevent decomposition and discoloration. Liquid barium fatty acid is usually a mixture of barium stearate (Ba(C 17 H 35 COO)2) or other barium organic acid salts, a light yellow or orange-yellow transparent liquid, insoluble in water but soluble in hot ethanol; stable in air and decomposes into corresponding acids and barium salts when encountering strong acids.

[0003] In liquid stabilizers, when using barium fatty acid alone, the stability is insufficient (poor initial coloring), and it needs to be compounded with soaps such as cadmium, zinc, calcium (such as Ba / Cd, Ba / Zn systems), organic auxiliary stabilizers, lubricants, antioxidants and other additives to achieve the heat stabilizer effect during PVC processing; among them: such as phosphite esters, β-diketones, epoxy compounds, etc., to enhance the synergistic effect; stearic acid, paraffin wax, etc., to improve processing fluidity; antioxidants to prevent oxidative degradation; cadmium fatty acid (Cd): to improve initial coloring (prevent early yellowing of PVC) and improve light stability; zinc fatty acid (Zn): to inhibit the "zinc burning" phenomenon (excessive zinc will cause PVC to suddenly turn black) and assist in improving the initial stability, and barium fatty acid ions (Ba) can efficiently neutralize HCl and block autocatalytic degradation. The long carbon chains of the stearate radicals of these barium, cadmium, and zinc provide a certain degree of internal and external lubricity and improve processing fluidity.

[0004] In the prior art, the quality of monomer products of barium fatty acid heat stabilizers is often unstable, mainly manifested in that it is very easy to become turbid within 3 - 15 days after product production, and a large number of crystals slowly precipitate, seriously affecting the use of the product; the frequency of this problem has increased significantly and does not occur in every batch of products. The reasons for these problems may be worker operation problems, equipment problems, phosphite raw material problems, or the quality problem of the core raw material barium hydroxide; if the turbidity becomes more and more serious, the frequency is higher and higher, and situations such as requests for returns and exchanges occur, it will seriously affect the reputation of barium-cadmium-zinc liquid stabilizer manufacturers and seriously affect the reputation of downstream PVC plastic processing enterprises; other suppliers' barium hydroxides were also replaced midway, but the effect was not ideal.

[0005] Patent CN 106397831 B introduces a preparation method of a liquid barium-zinc heat stabilizer, which is prepared by a "one-step" step-by-step single preparation process; the solvent and organic acid are heated to 70 - 80 °C, and after being kept warm until the organic acid in the reaction system is heated and dissolved to be clear and transparent, zinc oxide is added, and then an antioxidant and an auxiliary stabilizer are added to obtain a clear and transparent liquid, that is, the liquid barium-zinc heat stabilizer. The shelf life of the product prepared by this process method under normal seasonal storage is within 2 months, while the shelf life is shortened to only 3 - 15 days when stored under light or in the rainy season in summer. The deteriorated product does not meet the PVC production requirements, causing serious quality accidents in PVC production.

[0006] Patent CN 107057220 B discloses a process formula of a liquid barium / zinc transparent composite heat stabilizer for PVC. The raw material cost of the liquid barium / zinc transparent composite heat stabilizer obtained by this method is 1.2 - 4 times that of conventional barium-cadmium-zinc stabilizers, and when the product is applied downstream, customers also need to modify the PVC processing formula, which does not meet the requirements of economic production.

[0007] Deterioration such as turbidity mainly has two types, one is granular turbidity and the other is colloidal emulsifying turbidity. In the prior art, the method to solve the short shelf life and turbidity of barium fatty acid heat stabilizers is mainly to reduce the barium element content by increasing the dosage of various acids such as fatty acids, so as to achieve a long shelf life and approximate clarity and transparency within the shelf life of barium fatty acid heat stabilizers. By this method, the barium content is low, the mixed fatty acids are in excessive amount, the effect of the stabilizer is difficult to meet the requirements, the subsequent PVC processing process is complex to change, the technical requirements for the operation process are high, and the production cost increases significantly.

[0008] Excessive chloride ions, excessive sodium ions, and excessive impurities such as barium carbonate or barium sulfate in barium hydroxide lead to granular turbidity, a significant increase in the product viscosity, and a color deepening; hydrochloric acid-insoluble substances and sulfur elements in barium hydroxide not being controlled within the range will cause latex-like turbidity; insufficient feeding of barium hydroxide can reduce the turbidity, but it does not meet the actual application; increasing the feeding amount of barium hydroxide will significantly increase the turbidity, viscosity, and color of the product.

[0009] Therefore, there is an urgent need for a new method to solve the problems of short shelf life and easy turbidity of barium fatty acid heat stabilizers to overcome the above defects in the prior art. Summary of the Invention

[0010] In order to solve the technical problems of short shelf life and easy turbidity of barium fatty acid heat stabilizers, a preparation method and application of a liquid barium fatty acid heat stabilizer with a long shelf life are provided. The shelf life of the monomer of the barium fatty acid heat stabilizer produced by the method of the present invention is up to 10 - 16 months, without turbidity, and still remains transparent and liquid; after the monomer of the barium fatty acid heat stabilizer is stored for more than 10 months and then compounded for use, the effect is equivalent to that of the compounded product of the barium fatty acid heat stabilizer within 2 months after leaving the factory.

[0011] To achieve the above objectives, the present invention is realized through the following technical solutions:

[0012] A preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life, comprising the following steps:

[0013] Reacting a mixed acid with barium hydroxide monohydrate in an organic solvent through an acid-base neutralization reaction to obtain a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life;

[0014] Wherein the barium hydroxide monohydrate meets the following requirements: the content of barium hydroxide monohydrate ≥ 98.5 wt%, the chloride ion content ≤ 0.1 ppm, the sodium ion content ≤ 0.1 wt%, the carbonate content ≤ 0.1 wt%, the hydrochloric acid-insoluble matter ≤ 0.01 wt%, the iron ion ≤ 15 ppm, the sulfur element ≤ 10 ppm, and the transparency reaches at least the clarity standard No. 2 specified in HG / T 3484-1999.

[0015] Further, the method for obtaining the barium hydroxide monohydrate specifically comprises the following steps:

[0016] Reacting a barium-containing compound with hydrochloric acid to obtain a first aqueous barium chloride solution, adding modified activated carbon thereto, heating to 85 - 100 °C, maintaining the temperature and stirring for reaction for 60 - 100 min, then cooling to room temperature, obtaining a second aqueous barium chloride solution after multiple filtrations, and subjecting it to a double decomposition reaction with sodium hydroxide to obtain an aqueous barium hydroxide solution;

[0017] Adding hydrogen peroxide and activated carbon to the aqueous barium hydroxide solution, heating for reaction, filtering while it is hot for multiple times, and dehydrating, concentrating, centrifuging, and recrystallizing the filtrate after filtration to obtain barium hydroxide monohydrate.

[0018] Furthermore, the mass concentration of the hydrochloric acid is at least 20%; the molar ratio between the barium-containing compound and the hydrochloric acid is 1:0.5 - 3, preferably 1:0.6 - 1.2; the barium-containing compound is selected from one or more combinations of barium carbonate, barium hydroxide hydrate (including octahydrate and monohydrate), barium chloride, and barium nitrate, and the main component content in the barium-containing compound is greater than 98 wt%;

[0019] The mass fraction of the second barium chloride aqueous solution is greater than 15%;

[0020] The dosage of the modified activated carbon is 1% - 2% of the mass of barium chloride contained in the first barium chloride aqueous solution;

[0021] The mass fraction of the barium hydroxide aqueous solution is >10%; the dosage of hydrogen peroxide is 0.5% - 8% of the mass of barium hydroxide contained in the barium hydroxide aqueous solution, and the dosage of the activated carbon is 0.5% - 8% of the mass of barium hydroxide contained in the barium hydroxide aqueous solution.

[0022] Furthermore, the temperature of the heating reaction is 70 - 98°C, and the reaction time is 0.5 - 5 h; preferably, the temperature of the heating reaction is 80 - 95°C, and the reaction time is 1 - 2 h; the filtration is carried out using a filtration material with a particle size less than 1 μm;

[0023] The modified activated carbon is phosphoric acid-modified coconut shell activated carbon, and the activated carbon is sodium hydroxide-activated activated carbon, and the particle sizes of both are 5 - 50 μm;

[0024] Furthermore, the preparation method includes the following specific steps:

[0025] Mix the mixed acid, barium hydroxide monohydrate, and the organic solvent in a reaction kettle. The reaction kettle is externally connected to a circulating reactor. After the materials in the reaction kettle react, they can continuously react through the circulating reactor and re-enter the reaction kettle for cyclic reaction; under continuous stirring, heat up for condensation reflux. When the water output reaches more than 50 wt% of the theoretical value, start the circulating reactor. The pump of the circulating reactor is a screw pump. During the process, the high-speed sprayed liquid materials react with the unreacted barium hydroxide monohydrate again. When performing cyclic reaction, a reaction pressure of more than 0.4 MPa is generated. Control the reaction temperature of the reaction kettle and the circulating reactor to rise to no more than 130°C. The generated water is quickly subjected to vacuum pumping through vacuum distillation. When the water output reaches more than 95 wt% of the theoretical value or no water droplets are generated, stop heating and vacuum pumping. After cooling, discharge the material to obtain a light yellow or light brown-yellow transparent liquid fatty acid barium heat stabilizer monomer. The product obtained by using the circulating reactor has better transparency and a longer shelf life.

[0026] Furthermore, the mixed acid is one or more of n-alkyl carboxylic acids or iso-alkyl carboxylic acids with at least 6 carbon atoms, substituted or unsubstituted aromatic carboxylic acids; the organic solvent is selected from one or more of ethylene glycol monobutyl ether, diethylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol butyl ether, tripropylene glycol methyl ether, raffinate oil, and white oil.

[0027] Preferably, the mixed acid is selected from one or more combinations of octanoic acid, decanoic acid, lauric acid, oleic acid, stearic acid, palmitic acid, benzoic acid, p-tert-butylbenzoic acid; the organic solvent is selected from the combination of ethylene glycol monobutyl ether and raffinate oil.

[0028] More preferably, the mixed acid is selected from the combination of oleic acid, isooctanoic acid and p-tert-butylbenzoic acid, and the mass ratio of oleic acid, isooctanoic acid to p-tert-butylbenzoic acid is 3-5:1:1-3; the mass ratio of ethylene glycol monobutyl ether to raffinate oil is 1:1-1.5.

[0029] Furthermore, the mass ratio of barium hydroxide monohydrate, the mixed acid, and the organic solvent is 0.4-0.5:1:0.7-0.8.

[0030] On the other hand, the present invention provides the application of the liquid barium fatty acid heat stabilizer monomer obtained by the above preparation method in the preparation of a compound heat stabilizer, and the compound heat stabilizer is one of a barium-zinc stabilizer, a barium-cadmium stabilizer, and a barium-cadmium-zinc stabilizer.

[0031] Beneficial technical effects:

[0032] Through procedures such as pickling, adsorption filtration, double decomposition reaction, adsorption filtration, distillation, concentration, water washing, centrifugation, drying, and cyclic reaction, the present invention has produced a liquid barium fatty acid heat stabilizer with a long shelf life through a complete process. The shelf life can be up to more than 1 year, and the product remains transparent and unchanged in quality, solving the problems of easy turbidity and short shelf life of the products obtained by the industrial production of existing barium fatty acid heat stabilizers;

[0033] The utilization rate of barium hydroxide in the process of the present invention can reach up to 99%. The barium fatty acid heat stabilizer product produced by the process of the present invention has stable quality. After more than 1 year of regular observation, no turbidity or precipitation has occurred, and the thermal stability test results of the product stored for a long time are the same as those of high-quality products just produced. Description of the drawings

[0034] Figure 1 It is a schematic diagram of the connection relationship of the main components of the reaction device of the present invention;

[0035] Figure 2 It is the structure of the circulation reactor;

[0036] Figure 3 It is a dynamic test result diagram of a PVC product sample piece. Detailed implementation manners

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments and the accompanying drawings of the present invention. Obviously, the described embodiments are only a part rather than all of the embodiments of the present invention. The following description of at least one exemplary embodiment is actually illustrative only and in no way constitutes a limitation on the present invention or its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0038] Unless otherwise specifically stated, the numerical values set forth in these embodiments do not limit the scope of the present invention. Technologies and methods known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the said technologies and methods should be regarded as part of the specification. In all the examples shown and discussed here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0039] In addition, it should be noted that the use of terms such as "first" and "second" to limit the solutions is only for the convenience of distinguishing the solutions generated in each reaction step. Without otherwise stated, the above terms have no special meanings and therefore should not be construed as limiting the scope of protection of the present invention.

[0040] For the experimental methods without specific conditions indicated in the following embodiments, they are generally determined according to the national standards; if there are no corresponding national standards, they are carried out according to the general standard requirements or general methods.

[0041] Commercially available barium hydroxide monohydrate is a qualified product, in which the barium hydroxide content is at least 99.0 wt%, the chloride ion content does not exceed 0.2 ppm, the hydrochloric acid-insoluble matter does not exceed 0.05 wt%, and the iron ion content does not exceed 30 ppm.

[0042] Preparation example

[0043] Preparation of phosphoric acid-modified coconut shell activated carbon: 1000 kg of coconut shell activated carbon is immersed in 2000 mL of a 20% by mass phosphoric acid aqueous solution at 80°C for 24 hours. After filtration, it is then immersed in 2000 mL of a 16% by mass sodium hydroxide solution at 50°C for 12 hours, filtered, and the filter cake is kept at 240°C under a steam pressure of 3.0 Mpa for 3 hours. After cooling, phosphoric acid-modified coconut shell activated carbon is obtained.

[0044] Preparation of sodium hydroxide-activated activated carbon: 1000 kg of coconut shell activated carbon was immersed in 2000 mL of a 16% sodium hydroxide solution at 80 °C for 24 hours, filtered, and the filter cake was kept at 240 °C under 3.0 Mpa of steam pressure for 3 hours. After cooling, sodium hydroxide-modified coconut shell activated carbon was obtained.

[0045] Example 1

[0046] A preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life:

[0047] S1. React 1000 g of commercially available barium hydroxide monohydrate with 4000 mL of 10% hydrochloric acid by mass to obtain a 22% barium chloride aqueous solution by mass. Add 50 g of phosphoric acid-modified coconut shell activated carbon (particle size 5 - 50 microns) thereto, heat to 90 °C, keep stirring and reacting for 100 min, then cool to room temperature. Filter the liquid through a filter material with a particle size less than 1 micron three times. After filtration, a second barium chloride aqueous solution is obtained. React it with 2150 mL of 20 wt% sodium hydroxide solution to obtain 7150 mL of a 13.5% barium hydroxide aqueous solution;

[0048] Add 50 g of hydrogen peroxide (mass fraction 30%) and 50 g of sodium hydroxide-activated activated carbon (particle size 5 - 50 microns) to the barium hydroxide aqueous solution, heat to 80 °C and react for 1 h. While it is hot, filter the liquid through a filter material with a particle size less than 1 micron three times. After dehydration, the filtered filtrate is concentrated, centrifuged, and recrystallized (specific steps: control the Baume degree of the liquid during concentration between 30 Be′ and 35 Be′, cool and crystallize, the crystallization time is 10 - 20 h, centrifuge and dehydrate, wash with water until the pH is between 12 and 13, then centrifuge and dehydrate again, centrifuge at 2000 r / min) to obtain purified barium hydroxide monohydrate;

[0049] Perform index detection on the barium hydroxide monohydrate obtained in this step, and the results are as follows: the content of barium hydroxide monohydrate is 99.5 wt%, the chloride ion content is 0.01 ppm, the sodium ion content is 0.07 wt%, the carbonate content is 0.08 wt%, the hydrochloric acid-insoluble matter is 0.01 wt%, the iron ion content is 10 ppm, the sulfur element content is 8 ppm, and the transparency reaches at least the clarity standard No. 1 specified in HG / T 3484-1999;

[0050] S2. The schematic diagram of the connection relationship of the main components of the reaction device in this step is as Figure 1 , and the structure of the circulating reactor in the reaction device is as Figure 2 shown;

[0051] 66 g of mixed acid (50 g of oleic acid + 16 g of isocaprylic acid), 90 g of mixed solvent (40 g of ethylene glycol monobutyl ether + 50 g of raffinate), 48 g of p-tert-butylbenzoic acid, and 51 g of barium hydroxide monohydrate are put into a 500 mL reaction kettle. Under continuous stirring, the reaction kettle is externally connected to a circulation reactor. After the materials in the reaction kettle react, they can continuously react through the circulation reactor and re-enter the reaction kettle for circulation reaction. The pump of the circulation reactor is a screw pump. Heat up and heat for condensation reflux. Gradually condense out water until the water output reaches more than 50% of the theoretical value, then start the circulation reactor. During the process, the high-speed jet liquid materials react with the unreacted barium hydroxide monohydrate again. When circulating and reacting, a reaction pressure of more than 0.4 MPa is generated. Control the reaction temperature not to exceed 130 °C (including the reaction temperature in the reaction kettle and the circulation reactor). The generated water is quickly subjected to vacuum water extraction through vacuum distillation until no water droplets are generated. Stop heating and vacuum pumping. After cooling, discharge the material to obtain a light yellow or light brownish-yellow transparent liquid fatty acid barium heat stabilizer monomer. Place the product in the storage room for 3 days to 16 months, compare the transparency with the original sample, and observe that the transparency of the sample in this case remains completely transparent and does not become turbid or deteriorated after being stored for 12 - 16 months, which is a qualified product.

[0052] Example 2

[0053] A preparation method of a long-shelf-life liquid fatty acid barium heat stabilizer monomer:

[0054] S1. React 1000 g of commercially available barium hydroxide monohydrate with 4000 mL of hydrochloric acid with a mass fraction of 10% to obtain a first barium chloride aqueous solution with a mass fraction of 22%. Add 50 g of phosphoric acid-modified coconut shell activated carbon (particle size 5 - 50 microns) thereto, heat up to 85 °C, keep warm and stir for 80 min, then cool to room temperature. Filter the liquid through a filter material smaller than 1 micron 4 times. After filtration is completed, obtain a second barium chloride aqueous solution, and carry out a double decomposition reaction with 2150 mL of 20 wt% sodium hydroxide solution to obtain 7150 mL of a barium hydroxide aqueous solution with a mass fraction of 13.5%;

[0055] Add 45 g of hydrogen peroxide (mass fraction 30%) and 60 g of sodium hydroxide-activated activated carbon (particle size 5 - 50 microns) to the barium hydroxide aqueous solution, heat to 80 °C and react for 1 h. While it is hot, filter the liquid through a filter material smaller than 1 micron 2 times. After dehydration of the filtered filtrate, concentrate, centrifuge, and recrystallize (the specific steps are: control the Baume degree of the liquid material between 30 Be′ and 35 Be′ during concentration, cool and crystallize, the crystallization time is 10 - 20 h, centrifuge and dehydrate, wash with water until the pH is between 12 - 13, then centrifuge and dehydrate again, centrifuge at 2000 r / min) to obtain purified barium hydroxide monohydrate;

[0056] The barium hydroxide monohydrate obtained in this step was subjected to index detection, and the results are as follows: the content of barium hydroxide monohydrate is 99.3 wt%, the chloride ion content is 0.06 ppm, the sodium ion content is 0.05 wt%, the carbonate content is 0.06 wt%, the hydrochloric acid-insoluble matter is 0.005 wt%, the iron ion content is 8 ppm, the sulfur element content is 9 ppm, and the transparency reaches the clarity standard No. 1 specified in HG / T 3484-1999;

[0057] S2. 66 g of a mixed acid (50 g of oleic acid + 16 g of isooctanoic acid), 90 g of a mixed solvent (40 g of ethylene glycol monobutyl ether + 50 g of raffinate oil), 48 g of p-tert-butylbenzoic acid, and 51 g of the purified barium hydroxide monohydrate obtained in the above step were put into a 500 mL reaction kettle. Under continuous stirring, the reaction kettle was externally connected to a circulation reactor. After the materials in the reaction kettle reacted, they could continuously react through the circulation reactor and re-enter the reaction kettle for circulation reaction. The pump of the circulation reactor was a screw pump. The temperature was raised for heating and condensation reflux. When the amount of condensed water gradually reached more than 50% of the theoretical value, the circulation reactor was started. During the process, the high-speed sprayed liquid materials reacted fully with the unreacted barium hydroxide monohydrate again. A reaction pressure of more than 0.4 MPa was generated during the circulation reaction. The reaction temperature was controlled not to exceed 100 °C (including the reaction temperature in the reaction kettle and the circulation reactor). The generated water was quickly subjected to vacuum pumping through vacuum distillation until no water droplets were generated. Then, heating and vacuum pumping were stopped. After cooling, the product was discharged to obtain a light yellow or light brown-yellow transparent liquid fatty acid barium heat stabilizer monomer. The product was placed in a storage room for 3 days to 16 months. By comparing the transparency of the original sample, it was observed that the transparency of the sample in this case remained completely transparent after being stored for 10-12 months and was a qualified product without turbidity or deterioration.

[0058] Example 3

[0059] A preparation method of a liquid fatty acid barium heat stabilizer monomer with a long shelf life:

[0060] S1. 1000 g of commercially available barium hydroxide monohydrate was reacted with 4000 mL of hydrochloric acid with a mass fraction of 10% to obtain a first barium chloride aqueous solution with a mass fraction of 22%. 50 g of phosphoric acid-modified coconut shell activated carbon (particle size 5-50 microns) was added thereto, and the temperature was raised to 95 °C. After holding and stirring for 60 min, the temperature was lowered to room temperature. The liquid material was filtered 4 times through a filter material with a particle size less than 1 micron. After the filtration was completed, a second barium chloride aqueous solution was obtained, and it was subjected to a double decomposition reaction with 2150 mL of a 20 wt% sodium hydroxide solution to obtain 7150 mL of a barium hydroxide aqueous solution with a mass fraction of 13.5%;

[0061] 60 g of hydrogen peroxide (mass fraction 30%) and 45 g of sodium hydroxide-activated activated carbon (particle size 5 - 50 microns) are added to the aqueous barium hydroxide solution, and the mixture is heated to 80 °C and reacted for 1 h. While it is still hot, the liquid material is filtered twice through a filter medium with a particle size less than 1 micron. After dehydration, the filtered filtrate is concentrated, centrifuged, and recrystallized (the specific steps are as follows: during concentration, the Baumé degree of the liquid material is controlled between 30 Be′ and 35 Be′, then cooled for crystallization, and the crystallization time is 10 - 20 h. After centrifugal dehydration, it is washed with water until the pH is between 12 and 13, and then centrifuged again at 2000 r / min) to obtain purified barium hydroxide monohydrate;

[0062] The obtained barium hydroxide monohydrate is subjected to index detection, and the results are as follows: the content of barium hydroxide monohydrate is 99.7 wt%, the chloride ion content is 0.01 ppm, the sodium ion content is 0.01 wt%, the carbonate content is 0.01 wt%, the hydrochloric acid-insoluble matter is 0.002 wt%, the iron ion content is 3 ppm, the sulfur element content is 6 ppm, and the transparency reaches the clarity standard No. 1 specified in HG / T 3484 - 1999;

[0063] 66 g of a mixed acid (50 g of oleic acid + 16 g of isooctanoic acid), 90 g of a mixed solvent (40 g of ethylene glycol monobutyl ether + 50 g of raffinate), 48 g of p-tert-butylbenzoic acid, and 51 g of the purified barium hydroxide monohydrate obtained in the previous step are put into a 500 mL reaction kettle. Under continuous stirring, the reaction kettle is externally connected to a circulating reactor. After the materials in the reaction kettle react, they can continuously react through the circulating reactor and re-enter the reaction kettle for cyclic reaction. The pump of the circulating reactor is a screw pump. Heat is applied for condensation reflux. When the amount of condensed water gradually reaches more than 50% of the theoretical value, the circulating reactor is started. During this process, the high-speed jet liquid material reacts fully with the unreacted barium hydroxide monohydrate again. During the cyclic reaction, a reaction pressure of more than 0.4 MPa is generated, and the reaction temperature is controlled not to exceed 100 °C (including the reaction temperature in the reaction kettle and the circulating reactor). The generated water is quickly subjected to vacuum pumping through vacuum distillation until no water droplets are produced. Then, heating and vacuum pumping are stopped. After cooling, the product is discharged to obtain a light yellow or light brown-yellow transparent liquid fatty acid barium heat stabilizer monomer. The product is placed in a storage room for 3 days to 16 months, and the transparency of the original sample is compared. It is observed that the transparency of the sample in this case remains completely transparent and no turbidity or deterioration occurs after being stored for 12 - 14 months, which is a qualified product.

[0064] Example 4

[0065] A preparation method of a long-shelf-life liquid fatty acid barium heat stabilizer monomer:

[0066] S1. React 1000 g of commercially available barium hydroxide monohydrate with 4000 mL of hydrochloric acid with a mass fraction of 10% to obtain a first barium chloride aqueous solution with a mass fraction of 22%. Add 50 g of phosphoric acid-modified coconut shell activated carbon (particle size 5 - 50 microns) thereto, heat up to 90 °C, keep stirring and reacting for 70 min, then cool to room temperature. Filter the liquid through a filter material with a particle size less than 1 micron three times. After filtration, obtain a second barium chloride aqueous solution, and carry out a double decomposition reaction with 2150 mL of 20 wt% sodium hydroxide solution to obtain 7150 mL of barium hydroxide aqueous solution with a mass fraction of 13.5%;

[0067] Add 40 g of hydrogen peroxide (mass fraction 30%) and 40 g of sodium hydroxide-activated carbon (particle size 5 - 50 microns) to the barium hydroxide aqueous solution, heat to 70 °C and react for 1 h. Filter the liquid through a filter material with a particle size less than 1 micron twice while it is hot. After filtration, dehydrate the filtrate, and then carry out concentration, centrifugation, and recrystallization (specific steps: control the Baumé degree of the liquid during concentration between 30 Be′ and 35 Be′, cool down for crystallization, the crystallization time is 10 - 20 h, centrifuge for dehydration, wash with water until the pH is between 12 and 13, then centrifuge for dehydration again, centrifuge at 2000 r / min) to obtain purified barium hydroxide monohydrate;

[0068] Carry out index detection on the barium hydroxide monohydrate obtained in this step, and the results are as follows: the content of barium hydroxide monohydrate is 99.6 wt%, the chloride ion content is 0.02 ppm, the sodium ion content is 0.03 wt%, the carbonate content is 0.02 wt%, the hydrochloric acid-insoluble matter is 0.003 wt%, the iron ion is 9 ppm, the sulfur element is 6 ppm, and the transparency reaches the clarity standard No. 1 specified in HG / T 3484 - 1999;

[0069] S2. 66 g of mixed acid (50 g of oleic acid + 16 g of isooctanoic acid), 90 g of mixed solvent (40 g of ethylene glycol monobutyl ether + 50 g of raffinate), 48 g of p-tert-butylbenzoic acid, and 51 g of the purified barium hydroxide monohydrate obtained in the previous step are put into a 500 mL reaction kettle. Under continuous stirring, the reaction kettle is externally connected to a circulating reactor. After the materials in the reaction kettle react, they can continuously react through the circulating reactor and re-enter the reaction kettle for cyclic reaction. The pump of the circulating reactor is a screw pump. Heat up and carry out condensation reflux. Gradually condense out water until the water output reaches more than 50% of the theoretical value, then start the circulating reactor. During the process, the high-speed jet liquid material reacts fully with the unreacted barium hydroxide monohydrate again. When carrying out cyclic reaction, a reaction pressure above 0.4 MPa is generated. Control the reaction temperature not to exceed 120 °C (including the reaction temperature in the reaction kettle and the circulating reactor). The generated water is quickly subjected to vacuum water extraction through vacuum distillation until no water droplets are produced. Stop heating and vacuum pumping. After cooling, discharge the material to obtain a light yellow or light brown-yellow transparent liquid fatty acid barium heat stabilizer monomer. Place the product in the storage room for 3 days to 16 months, compare the transparency with the original sample, and observe that the transparency of the sample in this case remains completely transparent and does not become turbid or deteriorated after being stored for 10 - 12 months, which is a qualified product.

[0070] Comparative Example 1

[0071] The preparation of the fatty acid barium heat stabilizer monomer in this case is the same as that in Example 1, except that in the purification process of barium hydroxide monohydrate, it does not react with hydrochloric acid first to obtain the first barium chloride aqueous solution, and modified activated carbon is not used subsequently. It is filtered with a conventional slow filter paper (pore size 1 - 3 microns) (i.e., a filter material smaller than 1 micron is not used). Instead, commercially available barium hydroxide monohydrate is directly dissolved in water and hydrogen peroxide is added (activated carbon is not added), heated to 80 °C and reacted for 1 h, and then filtered while it is hot with a conventional slow filter paper. After the filtrate is dehydrated, it is concentrated, centrifuged, and recrystallized to obtain barium hydroxide monohydrate (unless otherwise specified, the dosage of substances, process conditions, etc. are the same as those in Example 1); the obtained barium hydroxide monohydrate is used to prepare the fatty acid barium heat stabilizer monomer.

[0072] Place the fatty acid barium heat stabilizer monomer product in this case in the storage room for 3 days to 16 months, compare the transparency with the original sample, and observe that the sample in this case becomes turbid and deteriorated after being stored for 3 months.

[0073] Comparative Example 2

[0074] The preparation of the fatty acid barium heat stabilizer monomer in this case is the same as that in Example 1, except that commercially available conventional barium hydroxide monohydrate is used as the raw material to obtain the fatty acid barium heat stabilizer monomer through an acid-base neutralization reaction with the mixed acid in an organic solvent. A conventional reaction kettle is used during the reaction process (a circulating reactor is not used), and the fatty acid barium heat stabilizer monomer prepared in this case is named as the conventional sample.

[0075] The product of this case was placed in the storage room for 3 days to 16 months, and the transparency of the original sample was compared. It was observed that the transparency of the sample in this case became turbid and deteriorated after being stored for 1 month.

[0076] Application Example

[0077] After storing the barium fatty acid heat stabilizer monomers prepared in Examples 1-4 for 10 months respectively, they were compounded with organic acid zinc monomers (composed of zinc p-tert-butylbenzoate, zinc isooctanoate, and zinc oleate. The specific ratio and preparation process adopted the S2 step of Example 1, and zinc oxide was used instead of barium during preparation) according to a mass ratio of 3:1 to obtain liquid barium-zinc stabilizers, which were respectively used in PVC products; the barium fatty acid heat stabilizer monomers just prepared in Comparative Example 2 were used to compound barium-zinc stabilizers, which were respectively used in PVC products.

[0078] The PVC products were made according to the formula: 100.0 g of polyvinyl chloride (PVC), 28.0 g of diisononyl phthalate (DINP), 1.45 g of barium-zinc stabilizer, and 1.05 g of magnesium-aluminum hydrotalcite. After being mixed evenly at 190 °C using a high-speed mixer, they were pressed into sheet samples with a thickness of 1.0 mm through a two-roll mill.

[0079] The above samples were respectively subjected to dynamic tests: The samples were cut into sample pieces of 15 cm × 15 cm, and then placed in a rotary oven at 190 °C. A small amount of sample pieces were taken out every 5 minutes, and sample pieces of 10 mm × 15 mm were cut out to observe their color change situations. The results are as Figure 3 shown. As Figure 3 can be seen, the color change situations of the sample pieces were observed in the dynamic test: The color would change from light to dark. The faster the color change, the worse the heat stability of the sample piece, which could reflect that the heat stability of the corresponding barium fatty acid stabilizer used was worse; the worse the transparency of the static sheet, the worse the transparency of the sample and the more turbid impurities there were. The transparencies of the static sheets obtained in the above examples were all better than those of conventional products; through the above tests, the heat stability situations of the corresponding barium fatty acid heat stabilizers could be reflected. From the dynamic test results, it was analyzed that the barium fatty acid stabilizer synthesized by the process of the present invention had good heat stability effects after long-term storage and also had effects that could not be compared with those of conventional processes.

[0080] The above is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A preparation method of a liquid barium fatty acid heat stabilizer monomer with a long shelf life, characterized in that The steps include: The mixed acid and barium hydroxide monohydrate are reacted in an organic solvent through an acid-base neutralization reaction to obtain a liquid fatty acid barium heat stabilizer monomer with a long shelf life; The barium hydroxide monohydrate meets the following requirements: barium hydroxide monohydrate content ≥98.5wt%, chloride ion content ≤0.1ppm, sodium ion content ≤0.1wt%, carbonate content ≤0.1wt%, hydrochloric acid insoluble matter ≤0.01wt%, iron ion ≤15ppm, sulfur element ≤10ppm, and the transparency at least reaches clarity standard No. 2 specified in HG / T3484-1999.

2. The preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life according to claim 1, characterized in that, The method for obtaining barium hydroxide monohydrate specifically comprises the following steps: reacting a barium-containing compound with hydrochloric acid to obtain a first barium chloride aqueous solution, adding modified activated carbon thereto, heating to 80-100° C., stirring and reacting for 60-100 minutes, then cooling to room temperature, filtering multiple times to obtain a second barium chloride aqueous solution, and performing a double decomposition reaction with sodium hydroxide to obtain a barium hydroxide aqueous solution; Hydrogen peroxide and activated carbon are added to the barium hydroxide aqueous solution, heated for reaction, filtered multiple times while hot, and the filtered filtrate is dehydrated, concentrated, centrifuged, and recrystallized to obtain barium hydroxide monohydrate.

3. The preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life according to claim 2, characterized in that, The mass fraction of the hydrochloric acid is at least 20%; the molar ratio of the barium-containing compound to the hydrochloric acid is 1:0.5-3; the barium-containing compound is selected from one or more combinations of barium carbonate, barium hydroxide hydrate, barium chloride, and barium nitrate, and the main component content of the barium-containing compound is greater than 98wt%; The mass fraction of the second barium chloride aqueous solution is greater than 15%; The amount of the modified activated carbon is 1%-2% of the mass of the barium chloride contained in the first barium chloride aqueous solution; The mass fraction of the barium hydroxide aqueous solution is greater than 10%; the amount of the hydrogen peroxide is 0.5%-8% of the mass of the barium hydroxide contained in the barium hydroxide aqueous solution, and the amount of the activated carbon is 0.5%-8% of the mass of the barium hydroxide contained in the barium hydroxide aqueous solution.

4. The preparation method of a liquid barium fatty acid heat stabilizer monomer with a long shelf life according to claim 2, characterized in that The heating reaction temperature is 70-98°C and the reaction time is 0.5-5h; the filtration is performed using a filter material with a particle size of less than 1 micron; The modified activated carbon is phosphoric acid-modified coconut shell activated carbon, and the activated activated carbon is sodium hydroxide-activated activated carbon. The particle sizes of the two are 5-50 microns.

5. The preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life according to claim 1, characterized in that, The preparation method comprises the following specific steps: Mix the mixed acid, barium hydroxide monohydrate and the organic solvent in a reaction kettle. The reaction kettle is externally connected to a circulation reactor. After the materials in the reaction kettle react, they can continuously react through the circulation reactor and re-enter the reaction kettle for circulation reaction. Under continuous stirring, heat up and carry out condensation reflux. When the water output reaches more than 50 wt% of the theoretical value, start the circulation reactor. The pump of the circulation reactor is a screw pump. During the process, the high-speed sprayed liquid materials react with the unreacted barium hydroxide monohydrate again. When carrying out circulation reaction, a reaction pressure of more than 0.4 MPa is generated. Control the reaction temperature of the reaction kettle and the circulation reactor to rise to no more than 130 °C. The generated water is subjected to vacuum water extraction by vacuum distillation. When the water output reaches more than 95 wt% of the theoretical value or no water droplets are generated, stop heating and vacuum pumping. After cooling, discharge the material to obtain a light yellow or light brownish-yellow transparent liquid fatty acid barium heat stabilizer monomer.

6. The preparation method of a liquid barium fatty acid heat stabilizer monomer with a long shelf life according to claim 5, characterized in that, The mixed acid is one or more of a normal or isomeric alkyl carboxylic acid with at least 6 carbon atoms, a substituted or unsubstituted aromatic carboxylic acid; the organic solvent is selected from one or more of ethylene glycol monobutyl ether, diethylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol butyl ether, tripropylene glycol methyl ether, raffinate oil, white oil.

7. The preparation method of a liquid barium fatty acid heat stabilizer monomer with a long shelf life according to claim 6, characterized in that, The mixed acid is selected from one or more combinations of octanoic acid, decanoic acid, lauric acid, oleic acid, stearic acid, palmitic acid, benzoic acid, p-tert-butylbenzoic acid; the organic solvent is selected from the combination of ethylene glycol monobutyl ether and raffinate oil.

8. The preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life according to claim 7, characterized in that, The mixed acid is selected from the combination of oleic acid, isooctanoic acid and p-tert-butylbenzoic acid, and the mass ratio of oleic acid, isooctanoic acid and p-tert-butylbenzoic acid is 3 - 5:1:1 - 3; the mass ratio of ethylene glycol monobutyl ether and raffinate oil is 1:1 - 1.

5.

9. The preparation method of a monomer of a liquid barium fatty acid heat stabilizer with a long shelf life according to any one of claims 1-8, characterized in that, The mass ratio of barium hydroxide monohydrate, the mixed acid, and the organic solvent is 0.4 - 0.5:1:0.7 - 0.

8.

10. Application of a liquid fatty acid barium heat stabilizer monomer in the preparation of a compound heat stabilizer, characterized in that, The liquid fatty acid barium heat stabilizer monomer is obtained by the preparation method according to any one of claims 1 - 9; the compound heat stabilizer is one of barium-zinc stabilizer, barium-cadmium stabilizer, barium-cadmium-zinc stabilizer.

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