CN115612174A

CN115612174A - PVC product and preparation method thereof

Info

Publication number: CN115612174A
Application number: CN202211242148.7A
Authority: CN
Inventors: 于瀚淼; 于京良
Original assignee: Qingdao Houde Tianyuan Innovation Technology Co ltd
Current assignee: Qingdao Houde Tianyuan Innovation Technology Co ltd
Priority date: 2022-10-11
Filing date: 2022-10-11
Publication date: 2023-01-17

Abstract

The invention belongs to the technical field of high polymer materials, and provides a PVC product and a preparation method thereof, wherein the method uses a zinc burning inhibitor prepared according to the following steps: adding fatty acid into a reaction kettle, preheating and stirring; filling nitrogen into the reaction kettle, evacuating, and adjusting the pressure in the reaction kettle to the reaction pressure; heating the reaction kettle to a reaction temperature, sequentially adding a catalyst, a defoaming agent and polyol, and adjusting the pressure in the reaction kettle to a reaction pressure; maintaining the reaction temperature and the reaction pressure, and reacting for 20-90 minutes until the acid value of the product is less than or equal to 50mgKOH/g to prepare the zinc burning inhibitor; the reaction temperature is 160-200 ℃, and the reaction pressure is 0.051-0.091 MPa. The zinc burning inhibitor adopted by the invention can effectively inhibit zinc burning, has excellent compatibility with PVC resin, has strong internal lubricity, and can reduce the using amount of internal lubricant in application products.

Description

PVC product and preparation method thereof

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to a PVC product and a preparation method thereof.

Background

In the processing process of PVC products, the PVC material can be processed and molded only at the temperature of over 160 ℃, and the PVC material can be thermally decomposed at the temperature of 120-130 ℃ to release hydrogen chloride gas, so that the processing process of PVC resin is influenced, and particularly the color of the PVC products is influenced. Researches show that if PVC plastics can contain a certain amount of impurities such as lead salt, metal soap, phenol, arylamine and the like, normal processing and application of the PVC plastics are not influenced, and the PVC plastics can play a role in delaying thermal decomposition to a certain extent. In order to achieve the purpose of preventing or delaying thermal decomposition, people begin to carry out a great deal of experimental research on the stabilizer for PVC, so that the establishment and the continuous development of a thermal stabilization auxiliary system are promoted. The common heat stabilizers mainly include (1) lead salt heat stabilizers, (2) organotin heat stabilizers, (3) metal soap heat stabilizers, and (4) epoxy ester heat stabilizers.

With the continuous development of society, people have higher and higher requirements on environmental protection. In the preparation and use of the heat stabilizer, people also pursue the use of five-toxic and environment-friendly materials. The composite environment-friendly heat stabilizer mainly containing the zinc-containing saponifiable matter has the advantages of no toxicity, environmental protection, good heat stabilizing effect and the like, so that the composite environment-friendly heat stabilizer has the widest application range and the best application prospect. However, when the zinc-containing saponified substance is used as an environment-friendly heat stabilizer, hydrogen chloride generated by thermal decomposition of the PVC resin and the zinc-containing saponified substance undergo a chemical reaction to generate zinc chloride, and the zinc chloride turns black in a thermal environment, so that the PVC product turns dark and black in appearance, which is called zinc burning in the PVC processing field, and is specifically characterized in that the product has black and gray stripes or all colors turn black. The existence of the zinc burning phenomenon not only seriously affects the service performance of the PVC product, but also destroys the appearance of the PVC product and directly affects the user experience. In order to eliminate the adverse effect of zinc burning on PVC stabilizers, one usually chooses to add a zinc burning inhibitor to inhibit zinc burning.

In order to eliminate the adverse effect of zinc burning on PVC products and their preparation processes, methods for inhibiting zinc burning have been sought. At present, most of commonly used zinc burning inhibitors are prepared from monopentaerythritol, and the monopentaerythritol can form a complex with zinc chloride to prevent the zinc chloride from catalyzing and degrading the polyvinyl chloride, so that the zinc burning is inhibited. However, monopentaerythritol is easy to sublime, so that powder is separated out when the PVC product is demoulded.

Therefore, it is very important to develop a PVC product and a method for preparing the same, which can reduce powder precipitation during demolding and prevent grooves from being formed on the outer surface of PVC.

Disclosure of Invention

In view of the above, the present invention provides an environment-friendly heat stabilizer for PVC and a preparation method thereof, which at least partially solve the problems in the prior art.

To achieve the object of the present invention, the present invention provides a method for preparing a PVC article using a zinc burning inhibitor prepared according to the following steps: adding fatty acid into a reaction kettle, preheating and stirring; filling nitrogen into the reaction kettle, evacuating, and adjusting the pressure in the reaction kettle to the reaction pressure; heating the reaction kettle to a reaction temperature, adding a catalyst, a defoaming agent and polyol, and adjusting the pressure in the reaction kettle to a reaction pressure; maintaining the reaction temperature and the reaction pressure, and reacting for 20-90 minutes until the acid value of the product is less than or equal to 50mgKOH/g to prepare the zinc burning inhibitor; the reaction temperature is 160-200 ℃, and the reaction pressure is 0.051-0.091 MPa.

Further, adding the polyol 2-10 minutes after adding the catalyst and the defoaming agent, and then adjusting the pressure in the reaction kettle to the reaction pressure; the preheating temperature is 60-130 ℃, the reaction temperature is 180-200 ℃, the reaction pressure is 0.061-0.081 MPa, and the reaction time is 30-60 minutes.

Further, the molar ratio of the fatty acid to the polyhydric alcohol is 0.3-3; the dosage of the catalyst is 0.1-4% of the total mass of the fatty acid and the polyalcohol; the dosage of the high-temperature defoaming agent is 0.1-2% of the total mass of the fatty acid and the polyalcohol; the fatty acid is selected from the group consisting of C8 to C18 fatty acids and mixtures thereof; the polyalcohol is selected from sorbitol and mannitol; the catalyst is Lewis alkali and salt; the high-temperature defoaming agent is selected from methyl silicone oil series XP-100.

Furthermore, after the preparation of the zinc burning inhibitor, the method also comprises the steps of discharging, slicing, cooling and crushing.

Furthermore, the zinc burning inhibitor is a mixture of partially internally dehydrated polyol fatty acid ester, the mixture contains compounds with structural formulas shown as formula I, formula II and formula III, the sum of the content of the compounds with the structural formulas shown as formula I, formula II and formula III is more than or equal to 96 percent,

wherein m is more than or equal to 2,n and less than or equal to 5,y and more than or equal to 2,x in the structural formula is an even number selected from 10-22.

Further, the zinc burning inhibitor accounts for 2-16 wt% of the total amount of the preparation raw materials of the PVC product.

Furthermore, the raw materials for preparing the PVC product also comprise at least one of zinc stearate, calcium stearate, an internal lubricant, an external lubricant, an auxiliary heat stabilizer, a hydrogen chloride absorbent, a filler and a functional compensation auxiliary agent.

Further, the internal lubricant is selected from at least one of glyceryl monostearate, glyceryl distearate and epoxy fatty acid ester; the external lubricant is at least one of PE wax, paraffin wax and synthetic wax; the auxiliary heat stabilizer is at least one selected from antioxidant, perchloric acid and salt, beta-diketone compound and phosphite ester; the hydrogen chloride absorbent is selected from at least one of hydrotalcite, brucite and zeolite; the filler is at least one of heavy calcium carbonate or light calcium carbonate; the functional compensation auxiliary agent is selected from at least one of a color phase regulator and a flow promoter.

Furthermore, the preparation raw materials of the PVC product also comprise 20 to 30 weight percent of zinc stearate, 0 to 5 weight percent of calcium stearate, 5 to 8 weight percent of internal lubricant, 12 to 30 weight percent of external lubricant, 0.1 to 2 weight percent of auxiliary heat stabilizer, 20 to 47 weight percent of hydrogen chloride absorbent, 20 to 50 weight percent of filler and 0 to 2 weight percent of functional compensation auxiliary agent.

In addition, the invention also provides a PVC product prepared by the method.

Compared with other PVC product preparation processes, the zinc burning inhibitor adopted by the invention does not use monopentaerythritol as a raw material, and does not generate a precipitation phenomenon in the production process of PVC products.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a graph showing the results of a static Cone test in which the starting material prepared according to the present invention was heated.

Detailed Description

The present invention will be further described with reference to specific examples, which are intended to provide those skilled in the art with a more complete, precise and thorough understanding of the inventive concepts and solutions of the present invention.

The invention provides a preparation method of a PVC product, which uses a zinc burning inhibitor prepared according to the following steps: adding fatty acid into a reaction kettle, preheating and stirring; filling nitrogen into the reaction kettle, evacuating, and adjusting the pressure in the reaction kettle to the reaction pressure; heating the reaction kettle to a reaction temperature, adding a catalyst, a defoaming agent and polyol, and adjusting the pressure in the reaction kettle to a reaction pressure; maintaining the reaction temperature and the reaction pressure, and reacting for 20-90 minutes until the acid value of the product is less than or equal to 50mgKOH/g to prepare the zinc burning inhibitor; the reaction temperature is 160-200 ℃, and the reaction pressure is 0.051-0.091 MPa.

Preferably, the polyhydric alcohol is added 2-10 minutes after the catalyst and the defoaming agent are added, and then the pressure in the reaction kettle is adjusted to the reaction pressure; the preheating temperature is 60-130 ℃, the reaction temperature is 180-200 ℃, the reaction pressure is 0.061-0.081 MPa, and the reaction time is 30-60 minutes.

Preferably, the preparation method further comprises the steps of discharging, slicing, cooling and crushing after the preparation of the zinc burning inhibitor.

Preferably, the molar ratio of the fatty acid to the polyhydric alcohol (0.3 to 3) is 1.

Preferably, the amount of the catalyst is 0.1-4% of the total mass of the fatty acid and the polyalcohol.

Preferably, the amount of the high-temperature defoaming agent is 0.1-2% of the total mass of the fatty acid and the polyalcohol.

Preferably, the fatty acid is selected from the group consisting of C8 to C18 fatty acids and mixtures thereof; the polyalcohol is selected from sorbitol and mannitol; the catalyst is Lewis alkali and salt; the high-temperature defoaming agent is selected from methyl silicone oil series XP-100.

Further, the fatty acid is selected from at least one of caprylic acid, isooctanoic acid, decacarbonic acid, lauric acid, myristic acid, palmitic acid and stearic acid.

The zinc burning inhibitor is a mixture of partially internally dehydrated polyol fatty acid ester, the mixture contains compounds with structural formulas shown as formula I, formula II and formula III, the sum of the contents of the compounds shown as formula I, formula II and formula III is more than or equal to 96 percent,

In some embodiments, the zinc burning inhibitor of the present invention accounts for 2wt% to 16wt% of the total weight of the raw materials for preparing the PVC product.

Furthermore, the raw materials for preparing the PVC product also comprise at least one of zinc stearate, calcium stearate, an internal lubricant, an external lubricant, an auxiliary heat stabilizer, a hydrogen chloride absorbent, a filler and other functional compensation auxiliaries.

In some embodiments, the internal lubricant is selected from at least one of glyceryl monostearate, glyceryl distearate, an epoxidized fatty acid ester.

In some embodiments, the external lubricant is selected from at least one of PE wax, paraffin wax, synthetic wax.

In some embodiments, the secondary heat stabilizer is selected from at least one of antioxidants, perchlorates, beta-diketones, phosphites.

In some embodiments, the hydrogen chloride absorbent is selected from at least one of hydrotalcite, brucite, zeolite.

In some embodiments, the filler is selected from at least one of ground calcium carbonate or light calcium carbonate; the other function compensation auxiliary agents are selected from at least one of a color phase regulator and a flow promoter.

In some embodiments, the color phase modifier is ultramarine.

In some embodiments, the flow promoter is a polyacrylate.

In some embodiments, the preparation raw material of the PVC product further comprises 20wt% to 30wt% of zinc stearate, 0wt% to 5wt% of calcium stearate, 5wt% to 8wt% of internal lubricant, 12wt% to 30wt% of external lubricant, 0.1wt% to 2wt% of auxiliary heat stabilizer, 20wt% to 47wt% of hydrogen chloride absorbent, 20wt% to 50wt% of filler, and 0wt% to 2wt% of other functional compensation additives.

The invention also provides a PVC product prepared according to the method.

It should be noted that, in the case of no conflict, the features in the following embodiments and examples may be combined with each other; moreover, based on the embodiments in the present disclosure, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present disclosure.

It should be noted that the descriptions of the process flow, parameters, etc. in the embodiments are exemplary and not meant to limit the scope of the invention. The test methods described in the following examples are, unless otherwise specified, conventional; the apparatus and materials are commercially available, unless otherwise specified.

Example 1: preparation of zinc burn inhibitor

1) Setting the material temperature in a range of 165 ℃ on a control system of a reaction device, and starting to heat;

2) Firstly, putting 80kg of stearic acid into a reaction kettle, opening an emptying valve, heating to 80 ℃, and starting stirring;

3) Closing the emptying valve, filling nitrogen and emptying for 3 times, adjusting the pressure to 0.085MPa, and isolating air;

4) When the temperature of the materials reaches 165 ℃, a feeding port is opened, then 0.266kg of catalyst calcium p-toluenesulfonate and 0.266kg of methyl silicone oil (200 centipoises) are slowly and sequentially added, after 3 minutes, 180kg of sorbitol is added again for vacuumizing, and the pressure is adjusted to reach 0.085MPa;

5) When the temperature of the material reaches 165 ℃ again, maintaining 0.085MP, reacting for 1.5 hours, detecting the acid value of a product by sampling, stopping the reaction to prepare a zinc burning inhibitor, turning off a heating power supply and a vacuum system, and discharging all the materials into a storage tank;

6) After all the materials are discharged into the storage tank, discharging the materials to a slicing machine for slicing; and (5) putting the slices into a buffer bin, cooling, crushing, packaging and warehousing.

Example 2: preparation of zinc burn inhibitor

440kg of palmitic acid and 190kg of mannitol were mixed according to the method of example 1, and then 12.8kg of aluminum p-toluenesulfonate catalyst, 12.8kg of methyl silicone oil (300 centipoise) defoaming agent, 175 ℃ and 0.091MPa were added to the mixture to react for 1 hour, and the product acid value was detected by sampling and the reaction was stopped at 47mgKOH/g, thereby obtaining a scorch inhibitor and obtaining a scorch inhibitor.

Example 3: preparation of zinc burning inhibitor

According to the method of the embodiment 1, 801kg of lauric acid and 176kg of sorbitol are mixed, 39kg of catalyst lanthanum paratoluenesulfonate and 39kg of methyl silicone oil (400 centipoises) defoamer are added, the mixture reacts for 1.3 hours under the conditions of 185 ℃ and 0.075MPa, the product acid value is detected to be 45mgKOH/g through sampling, the reaction is stopped, and the zinc burning inhibitor is prepared.

Examples 4 to 8: preparation of zinc burn inhibitor

The zincburn inhibitor was prepared according to the method of example 1 and the formula and parameters shown below.

Example 9: preparation of PVC articles

The raw materials are as follows (mass percent):

1. zinc stearate: 20 percent;

2. internal lubricant: glyceryl monostearate: 7 percent;

3. external lubricant: PE wax: 16 percent;

4. zinc burn inhibitors: example 1 preparation of the product: 3 percent;

5. auxiliary heat stabilizer: 1010 main antioxidant: 0.3 percent;

6. auxiliary heat stabilizer: beta-diketone auxiliary antioxidant: 0.2 percent;

7. hydrogen chloride absorbent: hydrotalcite: 15 percent;

8. filling agent: heavy calcium carbonate: 37.3 percent;

9. functional compensation type auxiliary agent: calcium acetylacetonate: 1.2 percent.

The raw materials are fully and uniformly mixed by mixing equipment to prepare the PVC product.

Example 10: preparation of PVC articles

The raw materials are as follows (mass percent):

1. zinc stearate: 24 percent;

2. internal lubricant: glyceryl monostearate: 8 percent;

3. external lubricant: natural plant waxes: 20 percent;

4. zinc burn inhibitors: example 2 preparation of the product: 4 percent;

5. auxiliary heat stabilizer: 1010 main antioxidant: 0.48 percent;

6. auxiliary heat stabilizer: acetylacetone auxiliary antioxidant: 0.32 percent;

7. hydrogen chloride absorbent: hydrotalcite: 20 percent;

8. filling agent: light calcium carbonate: 21.88 percent;

9. functional compensation type auxiliary agent: calcium acetylacetonate: 1.32 percent.

Example 11: preparation of PVC articles

The raw materials are as follows (mass percent):

1. zinc stearate: 22 percent;

2. internal lubricant: epoxy fatty acid ester: 6 percent;

3. external lubricant: PE wax: 15 percent;

4. zinc burn inhibitors: example 3 preparation of the product: 6 percent;

5. auxiliary heat stabilizer: 1010 main antioxidant: 0.6 percent;

6. auxiliary heat stabilizer: acetylacetone auxiliary antioxidant: 0.4 percent;

7. hydrogen chloride absorbent: zeolite: 17.6 percent;

8. filling agent: heavy calcium carbonate: 30 percent;

9. functional compensation type auxiliary agent: calcium acetylacetonate: 2.4 percent.

Test example 1

The static Congo red experiment is carried out by adopting the method recorded in GB2917.1-2002, the raw materials in examples 9-11 are added into a test tube together, and the test tube is heated below the highest burning resistant temperature of the corresponding PVC material (the PVC material obtained correspondingly is prevented from burning and blackening, and the evaluation of the test result on the performance of the zinc burning inhibitor is interfered), the reaction result is not blackened, only red, yellow or brown is displayed, and the color is developed in the normal Congo red test.

Referring to fig. 1, the raw material of example 9 still shows no black color in the congo red test when heated to 48 minutes, the thermal stability of the zinc burning inhibitor used in the present invention is good, the zinc burning inhibitor is not easy to be damaged, the thermal stability of the zinc burning inhibition performance is very good, and the zinc burning inhibition effect can be continuously achieved in the PVC product preparation process.

The results of the Congo red tests on the raw materials of examples 10 and 11 and the results of the Congo red tests on the mixed reaction of the zincburn inhibitors prepared in examples 1 to 8 with other raw materials for PVC products were comparable to those in FIG. 1.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are also within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A process for the preparation of PVC articles, characterized in that a zinc burning inhibitor prepared according to the following steps is used:

adding fatty acid into a reaction kettle, preheating and stirring;

filling nitrogen into the reaction kettle, evacuating, and adjusting the pressure in the reaction kettle to the reaction pressure;

heating the reaction kettle to a reaction temperature, adding a catalyst, a defoaming agent and polyol, and adjusting the pressure in the reaction kettle to a reaction pressure;

maintaining the reaction temperature and the reaction pressure, and reacting for 20-90 minutes until the acid value of the product is less than or equal to 50mgKOH/g to prepare the zinc burning inhibitor;

the reaction temperature is 160-200 ℃, and the reaction pressure is 0.051-0.091 MPa.

2. The method of claim 1, wherein:

adding the polyhydric alcohol 2-10 minutes after the catalyst and the defoaming agent are added, and then adjusting the pressure in the reaction kettle to the reaction pressure;

the preheating temperature is 60-130 ℃, the reaction temperature is 180-200 ℃, the reaction pressure is 0.061-0.081 MPa, and the reaction time is 30-60 minutes.

3. The production method according to claim 1, characterized in that:

the molar ratio of the fatty acid to the polyhydric alcohol is 0.3-3;

the dosage of the catalyst is 0.1-4% of the total mass of the fatty acid and the polyalcohol;

the dosage of the high-temperature defoaming agent is 0.1-2% of the total mass of the fatty acid and the polyalcohol;

the fatty acid is selected from the group consisting of C8 to C18 fatty acids and mixtures thereof;

the polyalcohol is selected from sorbitol and mannitol; the catalyst is Lewis alkali and salt; the high-temperature defoaming agent is selected from methyl silicone oil series XP-100.

4. The method of claim 1, wherein: after the zinc burning inhibitor is prepared, the steps of discharging, slicing, cooling and crushing are also included.

5. The method of claim 1, wherein: the zinc burning inhibitor is a mixture of partially internally dehydrated polyol fatty acid ester, the mixture contains compounds with structural formulas shown as formula I, formula II and formula III, the sum of the contents of the compounds shown as formula I, formula II and formula III is more than or equal to 96 percent,

6. The method according to any one of claims 1 to 5, wherein the zinc burning inhibitor accounts for 2 to 16wt% of the total amount of raw materials for the preparation of the PVC product.

7. The preparation method according to any one of claims 1 to 5, wherein the raw materials for preparing the PVC product further comprise at least one of zinc stearate, calcium stearate, an internal lubricant, an external lubricant, an auxiliary heat stabilizer, a hydrogen chloride absorbent, a filler and a functional compensation auxiliary agent.

8. The production method according to claim 7, wherein the internal lubricant is selected from at least one of glyceryl monostearate, glyceryl distearate, and an epoxidized fatty acid ester; the external lubricant is at least one of PE wax, paraffin wax and synthetic wax; the auxiliary heat stabilizer is at least one selected from antioxidant, perchloric acid and salt, beta-diketone compound and phosphite ester; the hydrogen chloride absorbent is selected from at least one of hydrotalcite, brucite and zeolite; the filler is at least one of heavy calcium carbonate or light calcium carbonate; the functional compensation auxiliary agent is selected from at least one of a color phase regulator and a flow promoter.

9. The preparation method of any one of claims 1 to 5, wherein the raw materials for preparing the PVC product further comprise 20 to 30wt% of zinc stearate, 0 to 5wt% of calcium stearate, 5 to 8wt% of internal lubricant, 12 to 30wt% of external lubricant, 0.1 to 2wt% of auxiliary heat stabilizer, 20 to 47wt% of hydrogen chloride absorbent, 20 to 50wt% of filler, and 0 to 2wt% of functional compensation auxiliary agent.

10. A PVC article prepared according to the process of any one of claims 1 to 9.