Antioxidant type suspended emulsion terminator for PVC (Polyvinyl Chloride) and preparation method of antioxidant type suspended emulsion terminator

Abstract

The invention belongs to the technical field of resin polymerization additives, and particularly relates to an antioxidant type suspended emulsion terminator for PVC (polyvinyl chloride) and a preparation method thereof, the antioxidant type suspended emulsion terminator comprises the following raw material components in parts by mass: 5-30 parts of phenolic antioxidant; 5 to 20 parts of a thioester antioxidant; 0.1-5 parts of an ultraviolet light absorber; 0.1 to 5 parts of a chain terminator; 1-10 parts of a heat stabilizer; 0.1 to 7 parts of a stabilizer; 0.1 to 5 parts of an emulsifier; 0.1-5 parts of a wetting dispersant; according to the invention, through the combination of the selected main and auxiliary antioxidants and the combination of the ultraviolet light absorber and the heat stabilizer, the defect structure of PVC is improved at the end of PVC polymerization, and meanwhile, the combination of the main and auxiliary antioxidants can quickly decompose peroxide and hydroperoxide at the later stage of processing; compared with the prior art, the whiteness and thermal stability of PVC in the early stage are good, the anti-yellowing effect and the long-term aging resistance of PVC in the later processing are more emphasized, the performance of PVC in the dynamic thermal stability is improved, and the volume impedance and the initial coloring are low.

Description

Technical Field

[0001] The invention belongs to the technical field of resin polymerization aids, and specifically relates to an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof. Background Art

[0002] In the production process of polyvinyl chloride, when the polymerization conversion rate reaches 85%, terminators must be added to stop the chain transfer reaction to ensure that polyvinyl chloride particles with the required degree of polymerization are obtained. Terminators are indispensable additives for the synthesis of polyvinyl chloride. With the continuous expansion of polyvinyl chloride production capacity and the intensification of industry competition, the requirements for upstream products are becoming increasingly stringent. Today, the demand for terminators has expanded from simple chain reaction termination to improving the whiteness, thermal stability time, anti-yellowing performance of PVC, as well as reducing the haze index, improving transparency, reducing initial coloring and meeting environmental protection standards.

[0003] The main types of terminators on the market include water-based terminators, suspension terminators, and emergency terminators. Water-based terminators are favored for their low price and efficient termination ability, but they contain a large amount of perchlorate, bisphenol A, sodium hydroxide and other substances. Although they can improve the whiteness and thermal stability of PVC, they cannot improve the structural defects of PVC. They only delay the degradation process, resulting in severe yellowing in later processing, high storage requirements, and poor environmental protection. In contrast, suspension terminators highlight their characteristics by adding large molecular weight primary antioxidants and thermal stabilizer components, but are limited by the processing method. They are mainly based on primary antioxidants, with fewer auxiliary antioxidants, and the product particle size is large, which has limited improvement on yellowing in later processing. These two types of products have poor anti-yellowing effects during the later processing of PVC, and have problems such as low transparency and high haze index, and have failed to effectively improve the dynamic thermal stability of PVC. Summary of the invention

[0004] The object of the present invention is to provide an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof, aiming to solve the problem that the two types of products proposed in the background technology have poor anti-yellowing effect during the later processing of PVC, have low transparency, high haze index and the like, and fail to effectively improve the dynamic thermal stability of PVC.

[0005] To achieve the above object, the present invention provides the following technical solution: an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof, comprising the following raw material components in parts by mass:

[0006]

[0007] As an antioxidant-type suspoemulsion terminator for PVC and a preparation method thereof of the present invention, the phenolic antioxidant is at least one of 2,6-di-tert-butylphenol, antioxidant 1010, antioxidant 2246, antioxidant 616 and antioxidant 264.

[0008] As an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof of the present invention, the thioester antioxidant is at least one of antioxidant 1412, antioxidant DLTP, antioxidant DSTP and antioxidant DTDTP.

[0009] As an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof of the present invention, the chain terminator is preferably at least one of N,N-diethylhydroxylamine, azopiperidinyl free radical, and N-isopropylhydroxylamine.

[0010] As an antioxidant type suspoemulsion terminator for PVC and its preparation method, the ultraviolet absorber is preferably at least one of 2-hydroxy-4-methoxybenzophenone, phenyl o-hydroxybenzoate and 2,4-dihydroxybenzophenone.

[0011] As an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof, the heat stabilizer is preferably at least one of fatty acid zinc, dihydropyridine, zinc isooctanoate, glycerol zinc and zinc acetate.

[0012] As an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof of the present invention, preferably, the stabilizer is at least one of ethylene glycol, carboxymethyl cellulose, starch and polyvinyl alcohol.

[0013] As an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof, the emulsifier is preferably at least one of nonylphenol polyoxyethylene ether, sodium dodecyl sulfate, sodium dodecylbenzene sulfonate and block polyether L61.

[0014] A method for preparing an antioxidant type suspoemulsion terminator for PVC comprises the following steps:

[0015] Step 1: Add the thioester antioxidant and ultraviolet absorber into the reactor A according to the required amount, raise the reactor temperature to 120-130°C, start stirring after all are melted, add phenolic antioxidant and heat stabilizer, stir evenly and then cool to 85-95°C.

[0016] Step 2: Add deionized water, emulsifier and stabilizer into reactor B, start stirring, raise the reactor temperature to 90-95°C, maintain constant temperature and completely dissolve the emulsifier and stabilizer for use.

[0017] Step 3: Slowly add the aqueous solution in reactor B to reactor A, set the speed at 500-1000r / min, and maintain a constant temperature of 85-95°C.

[0018] Step 4: When 1 / 2 of the aqueous solution is added, start the high shear emulsification mixture and set the shear speed at 1000-3000r / min. After all the aqueous solution is added, continue shearing for 30-60 minutes.

[0019] Step 5: After the shear emulsification is completed, turn off the high shear, cool the emulsion to 50-60°C with cooling water, add chain terminator and wetting dispersant. Continue stirring for 30 minutes, and use an emulsification pump to introduce the material into the storage kettle for standby use.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. By selecting a combination of main and auxiliary antioxidants, combined with ultraviolet absorbers and heat stabilizers, the defective structure of PVC is improved at the end of PVC polymerization. At the same time, the combination of main and auxiliary antioxidants can quickly decompose peroxides and hydroperoxides in the later stage of processing. The product not only shows good whiteness and thermal stability in the early static thermal stability of PVC, but also pays more attention to the anti-yellowing effect and long-term anti-aging performance of PVC in the later processing, which improves the performance of PVC in dynamic thermal stability, higher transparency, low haze index, low volume impedance, and low initial coloring.

[0022] 2. In addition to the antioxidant as a chain termination component, the formula of the present invention also assists with low molecular weight hydroxylamine or piperidine free radical chain termination components, thereby improving the problem of slow termination efficiency due to the large molecular weight of the antioxidant and reducing the amount of product added. The combination of antioxidants with different molecular weights can provide better termination efficiency.

[0023] 3. The emulsification scheme of the present invention adopts a three-stage emulsification, a phase transfer method in which emulsified water is gradually added to the oil phase, high-temperature high-shear emulsification is used to reduce the particle size, and an emulsification pump is used for further emulsification at low temperature. The three-stage emulsification scheme reduces the product particle size to 0.1-1 μm, and the product is more stable and has high long-term storage stability. The product particle size is uniform, and can be more evenly attached to the surface of PVC particles and enter the PVC gaps, and will not be lost in the centrifuge dehydration, and the long-term antioxidant effect is better during PVC processing.

[0024] 4. The preparation process has low power consumption, and a stable emulsion product can be obtained by simple low-speed shearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1, please refer to Figure 1 The present invention provides the following technical solution: an antioxidant type suspoemulsion terminator for PVC and a preparation method thereof, comprising the following raw material components by weight:

[0029]

[0030]

[0031] Preferably: the phenolic antioxidant is at least one of 2,6-di-tert-butylphenol, antioxidant 1010, antioxidant 2246, antioxidant 616 and antioxidant 264; the thioester antioxidant is at least one of antioxidant 1412, antioxidant DLTP, antioxidant DSTP and antioxidant DTDTP; the chain terminator is at least one of N, N-diethylhydroxylamine, nitrogen oxide piperidine free radical, N-isopropylhydroxylamine; the ultraviolet absorber is 2-hydroxy-4-methoxybenzophenone, o-hydroxybenzoic acid phenyl ester and 2,4-dimethoxybenzophenone. The invention comprises at least one of hydroxybenzophenone; the heat stabilizer is at least one of fatty acid zinc, dihydropyridine, zinc isooctanoate, glycerol zinc and zinc acetate; the stabilizer is at least one of ethylene glycol, carboxymethyl cellulose, starch and polyvinyl alcohol; the emulsifier is at least one of nonylphenol polyoxyethylene ether, sodium dodecyl sulfate, sodium dodecylbenzene sulfonate and block polyether L61; the wetting and dispersing agent is at least one of sodium diisooctyl succinate sulfonate, isooctyl alcohol polyoxyethylene ether phosphate, isooctyl alcohol polyoxyethylene ether and isomeric decanol polyoxyethylene ether.

[0032] Embodiment 2:

[0033] Step 1: Add the thioester antioxidant and ultraviolet absorber into the reactor A according to the required amount, raise the reactor temperature to 120-130°C, start stirring after all are melted, add phenolic antioxidant and heat stabilizer, stir evenly and then cool to 85-95°C.

[0034] Step 2: Add deionized water, emulsifier and stabilizer into reactor B, start stirring, raise the reactor temperature to 90-95°C, maintain constant temperature and completely dissolve the emulsifier and stabilizer for use.

[0035] Step 3: Slowly add the aqueous solution in reactor B to reactor A, set the speed at 500-1000r / min, and maintain a constant temperature of 85-95°C.

[0036] Step 4: When 1 / 2 of the aqueous solution is added, start the high shear emulsification mixture and set the shear speed at 1000-3000r / min. After all the aqueous solution is added, continue shearing for 30-60 minutes.

[0037] Step 5: After the shear emulsification is completed, turn off the high shear, cool the emulsion to 50-60°C with cooling water, add the chain terminator and wetting dispersant. Continue stirring for 30 minutes, and use an emulsification pump to introduce the material into the storage kettle to obtain the antioxidant type suspension emulsion terminator.

[0038] Example 3, as an optimization of the above example, the antioxidant is one or more combinations of 2,6-di-tert-butylphenol, antioxidant 1076, antioxidant 616, and antioxidant 1010.

[0039] Example 4, as an optimization of the above example, the thioester antioxidant is one or more combinations of the antioxidant DLTP, the antioxidant DSTP and the antioxidant DTDTP.

[0040] Example 5, as an optimization of the above example, the chain terminator is one or more combinations of N,N-diethylhydroxylamine, 2,2,6,6-tetramethyl-4-hydroxypiperidinyl nitroxide free radical 701, and N-isopropylhydroxylamine.

[0041] Example 6, as an optimization of the above example, the stabilizer is one or more combinations of ethylene glycol, polyvinyl alcohol 0399, and starch.

[0042] Example 7, as an optimization of the above example, the thermal stabilizer is one or more combinations of zinc octoate, fatty acid zinc or dihydropyridine.

[0043] Example 8, as an optimization of the above example, the emulsifier is one or more combinations of nonylphenol polyoxyethylene ether OP-10, block polyether L61, and sodium dodecylbenzene sulfonate LAS.

[0044] Example 9, as an optimization of the above example, the wetting and dispersing agent is sodium diisooctyl succinate sulfonate OT-75.

[0045] Example 10, as an optimization of the above step three, the stirring equipment is a dispersion disk plus paddle stirring, the paddle stirring speed is set to 500-800r / min, and the dispersion disk speed is set to 2000r / min.

[0046] Example 11, the PVC antioxidant type suspoemulsion is obtained according to the following preparation method:

[0047] Step 1: Add thioester antioxidant, ultraviolet absorber and phenol antioxidant into heating kettle A according to process values, control the temperature at 95-100° C., and heat until completely melted.

[0048] Step 2: Add deionized water, emulsifier and dispersing wetting agent into reactor B, stir until completely dissolved and then heat to 80-90°C.

[0049] Step 3: Add stabilizer and heat stabilizer components into reactor B, stir for 20 minutes, and then turn on high shear to perform shear emulsification for 20 minutes.

[0050] Step 4: Add the material flow in reactor A to reactor B, start high shear and high-speed dispersion in reactor B, start the emulsification pump for circulation, and continue shearing for 30 minutes to obtain an emulsion.

[0051] Step 5, cooling the emulsified emulsion to 40-50° C., adding a chain termination component, and stirring for 30 minutes to obtain an antioxidant suspension emulsion.

[0052] Example 12, in the optimization of the above Example 11, the high shear speed in step 3 is set to 2000r / min.

[0053] Example 13, in the optimization of the above Example 11, in step 4, the high shear speed is set to 2000 r / min, the high-speed dispersion disk speed is 1000 r / min, and the emulsification pump speed is 2000 r / min.

[0054] Example 14: The PVC antioxidant type suspoemulsion is prepared according to the following preparation method:

[0055] Step 1: Add thioester antioxidant, ultraviolet absorber and phenol antioxidant into heating kettle A according to process values, control the temperature at 95-100° C., and heat until completely melted.

[0056] Step 2: Add deionized water, emulsifier and dispersing wetting agent into reactor B, stir until completely dissolved and then heat to 80-90°C.

[0057] Step 3: Add stabilizer, heat stabilizer component and chain terminator component into reactor B, stir for 20 minutes, and then turn on high shear to perform shear emulsification for 20 minutes.

[0058] Step 4: Add the material flow in reactor A to reactor B, start high shear and high-speed dispersion in reactor B, and continue shearing for 30 minutes to obtain an emulsion.

[0059] Step 5: Pump the emulsion in reactor B into reactor A through an emulsifying pump, and cool naturally to room temperature to obtain an antioxidant suspension emulsion.

[0060] Example 15, an optimization of the above Example 14, wherein the chain terminator component is 2,2,6,6-tetramethyl-4-hydroxypiperidinyl nitroxide free radical 701.

[0061] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An antioxidant type suspoemulsion terminator for PVC, characterized in that: The raw material components are as follows:

2. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The phenolic antioxidant is at least one of 2,6-di-tert-butylphenol, antioxidant 1010, antioxidant 2246, antioxidant 616 and antioxidant 264.

3. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The thioester antioxidant is at least one of antioxidant 1412, antioxidant DLTP, antioxidant DSTP and antioxidant DTDTP.

4. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The chain terminator is at least one of N,N-diethylhydroxylamine, azopiperidinium free radical and N-isopropylhydroxylamine.

5. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The ultraviolet absorber is at least one of 2-hydroxy-4-methoxybenzophenone, phenyl o-hydroxybenzoate and 2,4-dihydroxybenzophenone.

6. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The heat stabilizer is at least one of fatty acid zinc, dihydropyridine, zinc isooctanoate, glycerol zinc and zinc acetate.

7. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The stabilizer is at least one of ethylene glycol, carboxymethyl cellulose, starch and polyvinyl alcohol.

8. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The emulsifier is at least one of nonylphenol polyoxyethylene ether, sodium dodecyl sulfate, sodium dodecylbenzene sulfonate and block polyether L61.

9. The antioxidant type suspoemulsion terminator for PVC according to claim 1, characterized in that: The wetting and dispersing agent is at least one of sodium diisooctyl succinate, isooctyl polyoxyethylene ether phosphate, isooctyl polyoxyethylene ether and isomeric decanol polyoxyethylene ether.

10. A method for preparing an antioxidant type suspoemulsion terminator for PVC, comprising any one of claims 1 to 9, characterized in that: The steps include: Step 1: Add the thioester antioxidant and ultraviolet absorber into the reactor A according to the required amount, raise the reactor temperature to 120-130°C, start stirring after all are melted, add the phenolic antioxidant and heat stabilizer, stir evenly and then cool to 85-95°C; Step 2: Add deionized water, emulsifier and stabilizer into the reaction kettle B, start stirring, raise the kettle temperature to 90-95°C, maintain constant temperature and completely dissolve the emulsifier and stabilizer for standby use; Step 3: Slowly add the aqueous solution in reactor B to reactor A, set the speed at 500-1000r / min, and maintain a constant temperature of 85-95°C; Step 4: When 1 / 2 of the aqueous solution is added, start the high shear emulsification mixture, set the shear speed at 1000-3000r / min, and continue shearing for 30-60min after all the aqueous solution is added; Step 5: After the shear emulsification is completed, turn off the high shear, cool the emulsion to 50-60°C with cooling water, add chain terminator and wetting dispersant. Continue stirring for 30 minutes, and use an emulsification pump to introduce the material into the storage kettle for standby use.

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