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

Abstract

The invention discloses an environment-friendly antioxidant terminator for PVC (polyvinyl chloride) and a preparation method of the environment-friendly antioxidant terminator, and belongs to the field of auxiliaries for PVC. Comprising one or more of hindered phenol antioxidants, auxiliary antioxidants, heat stabilizers, light stabilizers or terminators; b) a continuous phase comprising water containing an emulsifier, and / or a pH regulator, and / or an antifreeze agent; the oily inert substance is adhered to or wrapped on the surface of the dispersed phase and comprises one or more of a plasticizer, mineral oil, vegetable oil, alpha-styrene, organic tin and epoxidized soybean oil; wherein the melting point of the dispersed phase of which the surface is adhered or wrapped with the oily inert substance is controlled within 100 DEG C, and the density difference between the dispersed phase of which the surface is adhered or wrapped with the oily inert substance and the continuous phase is lower than 0.5 g / cm < 3 >. According to the environment-friendly antioxidant terminator, the storage stability of the environment-friendly antioxidant terminator for PVC can be improved, the preparation method is simple, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the field of PVC additives, in particular to an environmentally friendly antioxidant terminator for PVC and a preparation method thereof, which can greatly improve the stability of the antioxidant. Background Art

[0002] Environmentally friendly terminators are designed to prevent PVC from oxidative degradation caused by heat, light and oxygen. The main ingredients are generally hindered phenols and phosphites, which serve as primary and secondary antioxidants, respectively. The former inactivates free radicals, while the latter decomposes hydroperoxides to enhance synergy. However, environmental protection requirements are becoming more and more stringent, such as generally making active ingredients into water emulsions.

[0003] Many materials can improve the performance of PVC, but the compatibility of many materials limits the composition of antioxidant formulas. First, the compatibility between different materials is still a problem. If the compatibility of two materials is poor, the emulsion will be unstable and even precipitation will occur. Secondly, the density difference is also an important issue. If the density difference between the continuous phase and the dispersed phase is too large, the emulsion will also be unstable. Finally, the melting point difference is also a factor that needs to be considered. If the melting point of certain materials is too high, it will cause processing difficulties and affect production efficiency. Therefore, how to improve production efficiency and reduce production costs while ensuring product quality is the main challenge facing current technology.

[0004] The applicant has been committed to the research of environmentally friendly antioxidant terminators for PVC. For example, the patent application document with Chinese patent application number 201711421703.1 and application publication date May 22, 2018 discloses environmentally friendly antioxidant terminators for PVC and preparation methods thereof. The raw materials of environmentally friendly antioxidant terminators for PVC include plasticizers, heat stabilizers, phenolic antioxidants, phosphite antioxidants, sulfur-containing antioxidants, lipophilic surfactants, hydrophilic surfactants, cosolvents, thickeners and deionized water by weight. However, there are many materials in the environmentally friendly antioxidant terminator for PVC, and the shelf life needs to be improved.

[0005] Therefore, in order to enhance the storage stability of the environmentally friendly antioxidant terminator for PVC, it is urgent to develop an environmentally friendly antioxidant terminator for PVC and a preparation method thereof. Summary of the invention

[0006] 1. Problem to be solved

[0007] One of the purposes of the present invention is to provide an environmentally friendly antioxidant terminator for PVC, aiming to improve the storage stability of the environmentally friendly antioxidant terminator for PVC.

[0008] Another object of the present invention is to provide a method for preparing the above-mentioned environmentally friendly antioxidant terminator for PVC, so as to simplify the preparation method and improve production efficiency.

[0009] 2. Technical solution

[0010] In order to solve the above problems, the technical solution adopted by the present invention is as follows:

[0011] According to the purpose of the present invention, the first aspect of the present invention provides an environmentally friendly antioxidant terminator for PVC, comprising:

[0012] a) a dispersed phase, including one or more of a hindered phenol antioxidant, an auxiliary antioxidant, a heat stabilizer, a light stabilizer or a terminator;

[0013] b) a continuous phase, comprising water and an emulsifier, or the water further comprising a pH adjuster and / or an antifreeze agent;

[0014] c) Oily inert substances, adhering to or encapsulating the surface of the dispersed phase, including one or more of plasticizers, mineral oil, vegetable oil, α-styrene, organic tin, and epoxidized soybean oil; these oily inert substances themselves may not have the ability to improve the performance of PVC such as antioxidant, thermal stability or terminator, but if they have these properties, it will not affect them.

[0015] The melting point of the dispersed phase with the oily inert substance attached to or wrapped on the surface is controlled within 100°C, and the density difference between the dispersed phase with the oily inert substance attached to or wrapped on the surface and the continuous phase is less than 0.5 g / cm 3 .

[0016] When the above technical scheme is adopted, on the one hand, the compatibility problem between different dispersed phases is solved. By adhering or wrapping the water-insoluble oily inert substance on the surface of the dispersed phase, the oily inert substance acts as a "solvent", thereby improving the compatibility of the emulsion-type antioxidant terminator and improving the stability of the emulsion; on the other hand, the density difference problem is solved. By adding an oily inert substance with appropriate density, the density of the continuous phase and the dispersed phase is adjusted to make the density difference closer, thereby improving the stability of the emulsion (that is, if the density of the continuous phase is large, a low-density oily substance is added; if the density of the continuous phase is small, a high-density oily substance is added); finally, the melting point difference problem is also solved. By adding an oily inert substance with a low melting point, the melting point of part of the dispersed phase is reduced, making processing easier, improving production efficiency, and reducing production costs.

[0017] As a possible implementation scheme, the oily inert substance contains a plasticizer, and preferably the plasticizer accounts for 20% to 50%.

[0018] As a possible implementation scheme, the components and mass fractions of the environmentally friendly antioxidant terminator for PVC are as follows:

[0019] Dispersed phase 25-40 parts;

[0020] 50-70 parts of continuous phase;

[0021] 10-30 parts of oily inert substance;

[0022] Among them, in the dispersed phase:

[0023]

[0024] As a possible implementation scheme, the hindered phenol antioxidant is β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate octadecyl alcohol ester (1076), triethylene glycol bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] (245), 3,5-di-tert-butyl-4-hydroxyphenyl propionate octyl ester (1135), tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester (1 010), 2,6-di-tert-butyl-p-cresol (264), 2,2′-methylenebis(4-methyl-6-tert-butylphenol) (2246), 4,4′-thiobis(6-tert-butyl-3-methylphenol) (300), 4,6-bis(octylthiomethyl)-o-cresol (1520), 2,2′-mercaptoethylene glycol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (1035) or more thereof.

[0025] As a possible implementation scheme, the auxiliary antioxidant is one or more of dilauryl thiodipropionate (DLTP), distearyl thiodipropionate (DSTP), CPL, and pentaerythritol tetrakis (3-lauryl thiopropionate) (412S);

[0026] As a possible implementation scheme, the heat stabilizer is one or more of sodium perchlorate, mono- / di-pentaerythritol, and hydrotalcite;

[0027] As a possible implementation scheme, the light stabilizer is one or more of 2-hydroxy-4-octyloxybenzophenone (UV-531), 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole (UV-326), and hindered amine light stabilizer (GW-540).

[0028] As a possible implementation scheme, the terminator includes one or more of diethylhydroxylamine and ATSC.

[0029] In the case of the above technical solution, if too much material with a high melting point is added to the dispersed phase (for example, the melting point of CPL is above 105°C), it will cause processing difficulties and affect production efficiency; by adding water-insoluble oily inert substances, the melting point of some materials can be reduced, making processing easier. This method can solve the problem of melting point differences, improve production efficiency, and reduce production costs.

[0030] If the density difference between the dispersed phase and the continuous phase is too large, the emulsion will also become unstable (such as adding too much DLTP): the present invention can reduce the density of the dispersed phase by adding an oily inert substance with a density lower than that of the continuous phase, such as vegetable oil; conversely, the density of the dispersed phase can be increased, so that the density of the continuous phase and the dispersed phase are closer, thereby improving the stability of the emulsion. This method can solve the density difference problem, making the dispersed phase float or fall more slowly, and improving the stability of the emulsion.

[0031] If the compatibility between the dispersed phase materials is poor, the emulsion will be unstable and even precipitate (such as adding too much antioxidant 245); the present invention can improve the compatibility of the two materials and improve the stability of the emulsion by adding a water-insoluble oily inert substance. This method can solve the compatibility problem and make the emulsion more stable.

[0032] As a possible implementation scheme, the mass fraction of the oily inert substance is:

[0033]

[0034] Preferably, the plasticizer comprises 10 parts, mineral oil comprises 5 parts, vegetable oil comprises 5 parts, α-styrene comprises 1 part, organic tin comprises 2 parts, and epoxy soybean oil comprises 4 parts.

[0035] As a possible implementation scheme, the plasticizer includes one or more of diethylhexyl phthalate (DOP), diethylhexyl phthalate (DEHP), triglycerides, fatty acid methyl esters, tributyl citrate, cyclohexyl hexanoate, polyethylene terephthalate, polyethylene glycol polycarbonate, and polypropylene glycol polycarbonate.

[0036] As a possible implementation scheme, the mineral oil is one or more of liquid paraffin, white oil, vaseline, cycloparaffin oil, and chlorinated paraffin.

[0037] As a possible implementation scheme, the vegetable oil is one or more of soybean oil, rapeseed oil, cottonseed oil, corn oil, sunflower seed oil, peanut oil, camellia oil, and sesame oil.

[0038] The second aspect of the present invention provides a method for preparing an environmentally friendly antioxidant terminator for PVC, comprising the following steps:

[0039] S1, dispersed phase pretreatment step: dispersing the molten dispersed phase into an oily inert substance, heating and stirring at a temperature within 100° C. to obtain a pretreated dispersed phase;

[0040] S2, continuous phase preparation process: dissolving an emulsifier in water, or simultaneously dissolving a thickener and / or a pH adjuster and / or an antifreeze agent in water, and stirring thoroughly;

[0041] S3, dispersing the pretreated dispersed phase into the continuous phase, shearing and emulsifying, and obtaining an environmentally friendly antioxidant terminator for PVC.

[0042] As a possible implementation scheme, in step S3, the shear emulsification time is 15 to 20 minutes, and the shear rate is 3500 to 4000 r / min.

[0043] As a possible implementation scheme, the components and mass fractions are as follows:

[0044] Dispersed phase 25-40 parts;

[0045] 50-70 parts of continuous phase;

[0046] 10-30 parts of oily inert substance;

[0047] As a possible implementation scheme, the dispersed phase includes one or more of a hindered phenol antioxidant, an auxiliary antioxidant, a heat stabilizer, a light stabilizer or a terminator.

[0048] As a possible implementation, in the dispersed phase:

[0049]

[0050] As a possible implementation scheme, the hindered phenol antioxidant is β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate octadecyl alcohol ester (1076), triethylene glycol bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] (245), 3,5-di-tert-butyl-4-hydroxyphenyl propionate octyl ester (1135), tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester (1 010), 2,6-di-tert-butyl-p-cresol (264), 2,2′-methylenebis(4-methyl-6-tert-butylphenol) (2246), 4,4′-thiobis(6-tert-butyl-3-methylphenol) (300), 4,6-bis(octylthiomethyl)-o-cresol (1520), 2,2′-mercaptoethylene glycol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (1035) or more thereof.

[0051] As a possible implementation scheme, the auxiliary antioxidant is one or more of dilauryl thiodipropionate (DLTP), distearyl thiodipropionate (DSTP), CPL, and pentaerythritol tetrakis (3-lauryl thiopropionate) (412S).

[0052] As a possible implementation scheme, the heat stabilizer is one or more of sodium perchlorate, mono- / di-pentaerythritol, and hydrotalcite;

[0053] As a possible implementation scheme, the light stabilizer is one or more of 2-hydroxy-4-octyloxybenzophenone (UV-531), 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole (UV-326), and hindered amine light stabilizer (GW-540).

[0054] As a possible implementation scheme, the terminator includes one or more of diethylhydroxylamine and ATSC.

[0055] As a possible implementation, in the continuous phase:

[0056]

[0057] The emulsifier is one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, polyoxyethylene sorbitan monooleate, sorbitan trioleate, polyoxyethylene lauryl ether, octylphenol polyoxyethylene ether, and fatty alcohol polyoxyethylene ether;

[0058] The pH adjuster includes one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, sulfuric acid, hydrochloric acid, phosphoric acid, and stearic acid;

[0059] The antifreeze agent is one or more of ethanol, ethylene glycol, and propylene glycol;

[0060] The thickener is one or more of polyvinyl alcohol, xanthan gum, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl starch, sodium alginate, carrageenan and bentonite.

[0061] As a possible implementation scheme, the oily inert substance includes one or more of plasticizer, mineral oil, vegetable oil, α-styrene, organotin, and epoxidized soybean oil;

[0062] As a possible implementation scheme, the oily inert substance preferably contains a plasticizer, and the plasticizer preferably accounts for 20% to 50%.

[0063] The mass fraction of the oily inert substance is:

[0064]

[0065] As a possible implementation scheme, the plasticizer includes one or more of diethylhexyl phthalate (DOP), diethylhexyl phthalate (DEHP), triglycerides, fatty acid methyl esters, tributyl citrate, cyclohexyl hexanoate, polyethylene terephthalate, polyethylene glycol polycarbonate, and polypropylene glycol polycarbonate.

[0066] As a possible implementation scheme, the mineral oil is one or more of liquid paraffin, white oil, vaseline, cycloparaffin oil, and chlorinated paraffin.

[0067] As a possible implementation scheme, the vegetable oil is one or more of soybean oil, rapeseed oil, cottonseed oil, corn oil, sunflower seed oil, peanut oil, camellia oil, and sesame oil.

[0068] As a possible implementation, in the continuous phase:

[0069]

[0070] The emulsifier is one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, polyoxyethylene sorbitan monooleate, sorbitan trioleate, polyoxyethylene lauryl ether, octylphenol polyoxyethylene ether, and fatty alcohol polyoxyethylene ether;

[0071] The pH adjuster includes one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, sulfuric acid, hydrochloric acid, phosphoric acid, and stearic acid;

[0072] The antifreeze agent is one or more of ethanol, ethylene glycol, and propylene glycol;

[0073] The thickener is one or more of polyvinyl alcohol, xanthan gum, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl starch, sodium alginate, carrageenan and bentonite.

[0074] 3. Beneficial effects

[0075] Compared with the prior art, the present invention has the following beneficial effects:

[0076] The environmentally friendly antioxidant terminator for PVC of the present invention introduces water-insoluble oily inert substances. By introducing water-insoluble oily inert substances, such as styrene, plasticizer, mineral oil, vegetable oil, oily defoamer, etc., into the preparation process of the emulsion-type antioxidant terminator, firstly, the compatibility between different materials can be improved and the stability of the emulsion can be improved; secondly, the density difference between the continuous phase and the dispersed phase can be adjusted to be as small as possible; thirdly, the melting point of part of the dispersed phase material can be reduced, so that the processing temperature is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 This is a graph showing the particle size test results of Example 3. DETAILED DESCRIPTION

[0078] The present invention is further described below in conjunction with specific embodiments.

[0079] The present invention provides a method for preparing an environmentally friendly antioxidant terminator for PVC, comprising the following steps:

[0080] S1, dispersed phase pretreatment step: dispersing the molten dispersed phase into an oily inert substance, heating and stirring at a temperature within 100° C. to obtain a pretreated dispersed phase;

[0081] S2. Preparation of continuous phase: dissolve the emulsifier, thickener and pH adjuster in water in sequence and stir thoroughly; if antifreeze is required, add antifreeze agent;

[0082] S3, dispersing the pretreated dispersed phase into the continuous phase, shearing and emulsifying, and obtaining an environmentally friendly antioxidant terminator for PVC.

[0083] Among them, the materials and mass fractions of each component are as follows:

[0084] Dispersed phase 25-40 parts;

[0085] 50-70 parts of continuous phase;

[0086] 10-30 parts of oily inert substance;

[0087] Among them, in the dispersed phase:

[0088] 10 to 20 parts of hindered phenol antioxidants, including octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (1076), triethylene glycol bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] (245), octyl 3,5-di-tert-butyl-4-hydroxyphenyl propionate (1135), pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (101 0), 2,6-di-tert-butyl-p-cresol (264), 2,2′-methylenebis(4-methyl-6-tert-butylphenol) (2246), 4,4′-thiobis(6-tert-butyl-3-methylphenol) (300), 4,6-bis(octylthiomethyl)-o-cresol (1520), 2,2′-mercaptoethylene glycol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (1035), or more thereof;

[0089] and / or, 5 to 10 parts of auxiliary antioxidants, including one or more of dilauryl thiodipropionate (DLTP), distearyl thiodipropionate (DSTP), CPL, pentaerythritol tetrakis (3-lauryl thiopropionate) (412S);

[0090] and / or, 1 to 3 parts of a heat stabilizer, including one or more of sodium perchlorate, mono- / di-pentaerythritol, and hydrotalcite;

[0091] and / or, 0.5 to 2 parts of light stabilizers, including 2-hydroxy-4-octyloxybenzophenone (UV-531), 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole (UV-326), and hindered amine light stabilizer (GW-540);

[0092] And / or, 5 to 10 parts of a terminator, including one or more of diethylhydroxylamine and ATSC.

[0093] The continuous phase includes:

[0094] 30-65 parts of water, 1-10 parts of emulsifier, including one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, polyoxyethylene sorbitan monooleate, sorbitan trioleate, polyoxyethylene lauryl ether, octylphenol polyoxyethylene ether, and fatty alcohol polyoxyethylene ether;

[0095] and / or, 0 to 10 parts of a pH adjuster, including one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, sulfuric acid, hydrochloric acid, phosphoric acid, and stearic acid;

[0096] and / or, 0 to 20 parts of antifreeze agents, including one or more of ethanol, ethylene glycol, and propylene glycol;

[0097] And / or, 0 to 20 parts of thickeners, including one or more of polyvinyl alcohol, xanthan gum, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl starch, sodium alginate, carrageenan, and bentonite.

[0098] Oily inert substances include:

[0099] 0 to 30 parts of plasticizers, including one or more of dioctyl phthalate (DOP), diethylhexyl phthalate (DEHP), triglycerides, fatty acid methyl esters, tributyl citrate, cyclohexyl hexanoate, polyethylene terephthalate, polyethylene glycol polycarbonate, and propylene glycol polycarbonate;

[0100] and / or, 0-30 parts of mineral oil, including one or more of liquid paraffin, white oil, vaseline, naphthenic oil, and chlorinated paraffin;

[0101] and / or, 0 to 30 parts of vegetable oil, including one or more of soybean oil, rapeseed oil, cottonseed oil, corn oil, sunflower seed oil, peanut oil, camellia oil, and sesame oil;

[0102] and / or, 0 to 30 parts of α-styrene;

[0103] and / or, 0 to 30 parts of organic tin, in a specific embodiment, methyl tin mercaptan is selected;

[0104] And / or, 0 to 30 parts of epoxidized soybean oil.

[0105] The environmentally friendly antioxidant terminator for PVC prepared by using the above raw materials and proportions has strong stability: no precipitation and no stratification after being placed at room temperature for 3 months; no stratification in the centrifugal stability test, the initial D50 is 0.8-1.8 μm, the initial D90 is 2.4-3.6 μm, and the D50 is 0.9-1.9 μm and the D90 is 2.5-3.8 μm after being placed for 3 months. In order to avoid redundant description, several typical embodiments and comparative examples are listed below for illustration.

[0106] Example 1

[0107] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and the preparation method thereof is as follows:

[0108] First, prepare two main raw materials, antioxidant terminator 245 (10 parts) and DLTP (10 parts), and mix antioxidant terminator 245 and DLTP in a ratio of 1:1 to obtain mixture A. Then set the melting temperature to 70°C, the melting time to 30min, and the stirring rate to 500r / min to completely melt the antioxidant terminator into a liquid state. Add 10 parts of diisooctyl phthalate and 5 parts of white oil to the liquid mixture A. Place the mixture A and the oily inert substance in a heating device, heat to 50°C, and keep the temperature constant. While heating, stir the mixture at a high speed, with a stirring speed of 1500r / min and a stirring time of 30min. Add a mixture of 65 parts of deionized water and 2 parts of sodium dodecylbenzene sulfonate, and continue stirring for 10min to mix evenly. Shear emulsification, place the antioxidant mixture under a shearing machine for shear emulsification for 15min, and the shear rate is 3500r / min. After the shearing is completed, the mixture is cooled to room temperature to obtain a stable emulsion type antioxidant terminator. Through the above steps, a stable and uniform emulsion type antioxidant terminator can be obtained.

[0109] Example 2

[0110] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and the preparation method thereof is as follows:

[0111] First, prepare two main raw materials, antioxidant terminator CPL (15 parts) and 1076 (15 parts), and mix antioxidant terminator CPL and 1076 in a ratio of 1:1 to obtain mixture A. Add 8 parts of tributyl citrate and 5 parts of soybean oil to liquid mixture A. Put the mixture of mixture A and oily inert substance into a heating device, then set the melting temperature to 80°C, the melting time to 20min, and the stirring rate to 500r / min to completely melt the antioxidant terminator into a liquid state. After complete dissolution, stir the mixture at a high speed of 2000r / min and a stirring time of 30min. Add a mixed solution of 57 parts of deionized water and 5 parts of octylphenol polyoxyethylene ether, and continue stirring for 10min to mix evenly. Shear emulsification, place the antioxidant mixture under a shearing machine for shear emulsification for 20min, and the shear rate is 4000r / min. After the shearing is completed, cool the mixture to room temperature to obtain a stable emulsion antioxidant terminator. Through the above steps, a stable and uniform emulsion type antioxidant terminator can be obtained.

[0112] Example 3

[0113] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and the preparation method thereof is as follows:

[0114] First, two main raw materials, antioxidant terminator 1076 (10 parts) and DLTP (20 parts), were prepared, and antioxidant terminator 1076 and DLTP were mixed in a ratio of 1:2 to obtain mixture A. Then, the melting temperature was set to 70°C, the melting time was 30min, and the stirring rate was 500r / min, and the antioxidant terminator was completely melted into a liquid state. 8 parts of triglyceride, 4 parts of fatty acid methyl ester, and 5 parts of cottonseed oil were added to the liquid mixture A. The mixture of mixture A and the oily inert substance was placed in a heating device, heated to 50°C, and the temperature was kept constant. While heating, the mixture was stirred at a high speed, with a stirring speed of 1500r / min and a stirring time of 40min. A mixture consisting of 53 parts of deionized water, 3 parts of polyoxyethylene sorbitan monooleate, and 1 part of dehydrated sorbitan trioleate was added, and the mixture was stirred for 10min to mix evenly. Shear emulsification, the antioxidant mixture was placed under a shearing machine for shear emulsification for 15min, and the shear rate was 4000r / min. After the shearing is completed, the mixture is cooled to room temperature to obtain a stable emulsion type antioxidant terminator. Through the above steps, a stable and uniform emulsion type antioxidant terminator can be obtained.

[0115] Example 4

[0116] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and its preparation method is basically the same as that of Example 1, except that 15 parts of mineral oil are added to the liquid mixture A, and no diisooctyl phthalate is added.

[0117] Example 5

[0118] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and its preparation method is basically the same as that of Example 2, except that 13 parts of soybean oil are added to the liquid mixture A, and tributyl citrate is not added.

[0119] Example 6

[0120] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and its preparation method is basically the same as that of Example 3, except that: 25 parts of cottonseed oil are added to the liquid mixture A, and no triglyceride or fatty acid methyl ester is added.

[0121] Example 7

[0122] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and its preparation method is basically the same as that of Example 3, except that: 1 part of α-styrene is also added to the liquid mixture A.

[0123] Example 8

[0124] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and its preparation method is basically the same as that of Example 7, except that: 2 parts of organic tin are also added to the liquid mixture A.

[0125] Example 9

[0126] This embodiment provides an environmentally friendly antioxidant terminator for PVC, and its preparation method is basically the same as that of Example 8, except that 4 parts of epoxidized soybean oil are further added to the liquid mixture A.

[0127] Comparative Example 1

[0128] This comparative example provides a method for preparing a stable emulsion-type antioxidant terminator, and the preparation method is as follows: the difference from Example 1 is that diisooctyl phthalate and white oil are not added to the liquid mixture A.

[0129] Comparative Example 2

[0130] This comparative example provides a method for preparing a stable emulsion-type antioxidant terminator, and the preparation method is as follows: the difference from Example 2 is that tributyl citrate and soybean oil are not added to the liquid mixture A.

[0131] Comparative Example 3

[0132] This comparative example provides a method for preparing a stable emulsion-type antioxidant terminator, and the preparation method is as follows: the difference from Example 1 is that triglyceride, fatty acid methyl ester and cottonseed oil are not added to the liquid mixture A.

[0133] Performance Testing

[0134] The technical performance indicators of the emulsion composite antioxidant obtained in the above examples and comparative examples were tested, and the testing method is as follows:

[0135] Static stability test: Place at room temperature for three months to observe whether precipitation or stratification occurs;

[0136] Centrifugal stability test: set the centrifugal speed to 4000r / min, the centrifugal time to 10min, and observe whether the antioxidant emulsion is stratified;

[0137] Particle size: The BT-9300ST laser particle size analyzer produced by Dandong Better Instrument Co., Ltd. was used to observe the initial D50 and D90 particle sizes of the emulsion and the particle size of the emulsion after 3 months; Figure 1 This is a graph showing the test results of the initial particle size of the emulsion in Example 3.

[0138] The results of the above tests are shown in Table 1 below:

[0139] Table 1 Test results of examples and comparative examples

[0140]

[0141] From the test results of Table 1, it can be seen that the method for preparing a stable emulsion-type antioxidant terminator provided in each embodiment has good storage stability and centrifugal stability for 3 months, and the D50 particle size is 0.8-1.8 μm, and the D90 particle size is 2.4-3.6 μm. The particle size is small, which is conducive to the stability of the emulsion; after being placed for 3 months, the D50 particle size is 0.9-1.9 μm, and the D90 particle size is 2.5-3.8 μm. The particle size appears to be agglomerated, but it is not obvious and does not affect the stability of the emulsion. The preparation method adopted by the present invention is simple to operate, has low energy consumption, and is energy-saving and environmentally friendly. Compared with Example 1, Comparative Example 1 does not contain plasticizer, 245 has poor compatibility, and precipitation occurs; in addition, the particle size of the antioxidant emulsion that has not precipitated increases, and the stability decreases; in Comparative Example 3, since no mineral oil or other substances are added during the emulsification and dispersion process, the density difference between the continuous phase and the dispersed phase is large, and the dispersed phase material continues to float, so obvious stratification occurs during centrifugation, and the solid content of the surface layer becomes higher and higher after standing, so the fluidity becomes worse and the antioxidant becomes thicker.

[0142] The melting points of CPL in Comparative Example 2 and Example 2 are relatively high, and generally the processing temperature needs to be above 120° C. Since there is no oily substance in Comparative Example 2, the melting point does not decrease, and an emulsion cannot be prepared.

[0143] Specifically:

[0144] Examples 4 to 6 correspond to Examples 1 to 3 respectively. The plasticizer is removed from the oily inert substance, and only mineral oil or vegetable oil is contained. The plasticizer-free antioxidant in Examples 4 to 6 will affect the fluidity appearance of the antioxidant emulsion and the post-processing performance of PVC (mainly manifested as: reduced processing fluidity, reduced PVC flexibility, and poor impact resistance).

[0145] Compared with Example 3, Examples 7 to 9 respectively add α-styrene, organotin, and epoxidized soybean oil, wherein α-styrene, as an oily inert substance, can improve the compatibility between the dispersed phase and the continuous phase and between the components in the dispersed phase; organotin can synergize with hindered phenol antioxidants, auxiliary antioxidants, etc. to enhance the thermal stability of materials such as PVC; Epoxidized soybean oil has a plasticizing effect, which can increase the flexibility and plasticity of the material, and also helps to improve the stability of the antioxidant system.

[0146] Comparative Examples 1 to 3 correspond to Examples 1 to 3 one by one, except that the oily inert substances are removed. In Comparative Example 1, there is no dioctyl phthalate or white oil, which will lead to an increase in the viscosity of the antioxidant emulsion, a decrease in fluidity, an increase in the emulsion particle size, and a decrease in stability; in Comparative Example 2, due to the absence of oily inert substances (such as tributyl citrate and soybean oil), the CPL melting point is relatively high, and the material cannot be smoothly melted at the same processing temperature, resulting in the inability to prepare an emulsion; in Comparative Example 3, there is no triglyceride, fatty acid methyl ester, or cottonseed oil, which will lead to a decrease in the stability of the antioxidant emulsion and an increase in the particle size.

[0147] Although the present invention has been described in detail above by means of general description, specific implementation methods and tests, it is obvious to those skilled in the art that some modifications or improvements may be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. An environmentally friendly antioxidant terminator for PVC, characterized in that: include: a) a dispersed phase, including one or more of a hindered phenol antioxidant, an auxiliary antioxidant, a heat stabilizer, a light stabilizer or a terminator; b) a continuous phase, comprising water and an emulsifier, or the water further comprising a pH adjuster and / or an antifreeze agent; c) Oily inert substances, adhering to or encapsulating the surface of the dispersed phase, including one or more of plasticizers, mineral oils, vegetable oils, α-styrene, organotin, and epoxidized soybean oil; The melting point of the dispersed phase with the oily inert substance attached to or wrapped on the surface is controlled within 100°C, and the density difference between the dispersed phase with the oily inert substance attached to or wrapped on the surface and the continuous phase is less than 0.5 g / cm 3 .

2. An environmentally friendly antioxidant terminator for PVC according to claim 1, characterized in that: The oily inert substance contains plasticizer, and the plasticizer accounts for 20% to 50%.

3. An environmentally friendly antioxidant terminator for PVC according to claim 2, characterized in that: The oily inert substance includes: 10 parts of plasticizer, 5 parts of mineral oil, 5 parts of vegetable oil, 1 part of α-styrene, 2 parts of organic tin and 4 parts of epoxidized soybean oil.

4. The environmentally friendly antioxidant terminator for PVC according to claim 1, characterized in that: The plasticizer includes one or more of di-2-ethylhexyl phthalate, diethylhexyl phthalate, triglyceride, fatty acid methyl ester, tributyl citrate, cyclohexyl hexanoate, polyethylene terephthalate, polyethylene glycol polycarbonate, and propylene glycol polycarbonate; the mineral oil is one or more of liquid paraffin, white oil, vaseline, cyclohexane oil, and chlorinated paraffin; the vegetable oil is one or more of soybean oil, rapeseed oil, cottonseed oil, corn oil, sunflower seed oil, peanut oil, camellia oil, and sesame oil.

5. The environmentally friendly antioxidant terminator for PVC according to claim 1, characterized in that: The mass fractions of dispersed phase, continuous phase and oily inert substance are as follows: Dispersed phase 25-40 parts; 50-70 parts of continuous phase; 10 to 30 parts of oily inert substance.

6. The environmentally friendly antioxidant terminator for PVC according to claim 1, characterized in that: The components and mass fractions in the dispersed phase are as follows:

7. An environmentally friendly antioxidant terminator for PVC according to claim 1, characterized in that: The hindered phenol antioxidant is one or more of 1076, 245, 1135, 1010, 264, 2246, 300, 1520, and 1035; The auxiliary antioxidant is one or more of DLTP, DSTP, CPL, and 412S; The heat stabilizer is one or more of sodium perchlorate, mono- / di-pentaerythritol, and hydrotalcite; The light stabilizer is one or more of UV-531, UV-326, and GW-540; The terminator includes one or more of diethylhydroxylamine and ATSC.

8. An environmentally friendly antioxidant terminator for PVC according to any one of claims 1 to 7, characterized in that: The D50 of the environmentally friendly antioxidant terminator is 0.8-1.8 μm, and the D90 is 2.4-3.6 μm.

9. A method for preparing the environmentally friendly antioxidant terminator for PVC according to claim 8, characterized in that: The steps are: S1, dispersed phase pretreatment step: dispersing the molten dispersed phase into an oily inert substance, heating and stirring at a temperature within 100° C. to obtain a pretreated dispersed phase; S2, continuous phase preparation process: dissolving an emulsifier in water, or simultaneously dissolving a thickener and / or a pH adjuster and / or an antifreeze agent in water, and stirring thoroughly; S3, dispersing the pretreated dispersed phase into the continuous phase, shearing and emulsifying, and obtaining an environmentally friendly antioxidant terminator for PVC.

10. The method for preparing the environmentally friendly antioxidant terminator for PVC according to claim 9, characterized in that: In step S3, the shear emulsification time is 15 to 20 minutes, and the shear rate is 3500 to 4000 r / min.

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