Compound polymerization inhibitor
By combining nitrile radical heterocyclic compounds with reducing agents and phenolic polymerization inhibitors, a compound polymerization inhibitor is formed that exhibits better stability at high temperatures. This solves the problems of self-polymerization and decomposition of nitrile radical polymerization inhibitors, enabling longer-term stable use and wider applicability.
Patent Information
- Application Number
- CN202512019707.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-02-27
AI Technical Summary
Existing nitrogen oxide free radical inhibitors are prone to self-polymerization and decomposition at high temperatures, resulting in unstable performance, especially during the hot summer months when precipitates form.
By selectively compounding nitrile and oxygen radical heterocyclic compounds with reducing agents and phenolic polymerization inhibitors, and using water as a solvent, a compounded polymerization inhibitor is formed. The reducing agent removes free radical active species, and the phenolic polymerization inhibitor converts free radicals into stable states, thus synergistically inhibiting self-polymerization and decomposition.
It significantly improves the high-temperature stability and effectiveness of the polymerization inhibitor, extends the stabilization time from 25 days to several months, solves the problem of precipitation at high temperatures, and has a wider range of applications.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of chemical production, and specifically relates to a compound polymerization inhibitor. Background Technology
[0002] As is well known, unsaturated olefins are chemically highly reactive due to their conjugated π bonds during production, storage, and transportation, readily self-polymerizing into high molecular weight polymers. These polymers can cause equipment and pipeline blockages, leading to increased system pressure or differential pressure, deterioration of heat and mass transfer, and obstruction of material transport, even causing serious accidents. To prevent the formation of these polymers, the use of polymerization inhibitors has become a routine measure. Polymerization inhibitors prevent the reaction by converting chain free radicals into stable molecules or stable free radicals, effectively inhibiting the polymerization of unsaturated olefins.
[0003] Driven by strong market demand for high-efficiency, energy-saving, and environmentally friendly products, Zhenxing Chemical's star product—polymerization inhibitor 701 (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxy radical)—stands out with its superior performance and unique advantages. Inhibitor 701 is environmentally friendly, clean, and has minimal skin irritation, making it a green polymerization inhibitor. It is easy to use, soluble in various organic solvents and water, allowing for the preparation of aqueous solutions for convenient feeding. Polymer residues on equipment trays and pipelines become granular after using inhibitor 701, making them easy to clean and saving customers significant cleaning costs. Furthermore, this inhibitor is widely applicable in various scenarios, exhibiting excellent polymerization inhibition effects on olefins and their derivatives (such as acrylates, methacrylates, acrylic acid, acrylonitrile, styrene, butadiene, etc.) during production, separation, purification, storage, and transportation.
[0004] However, nitroxide radical inhibitors like polymerization inhibitor 701 become more active at high temperatures, leading to enhanced intermolecular interactions and causing self-polymerization and decomposition reactions. Prepared aqueous solutions will develop varying degrees of sedimentation after prolonged outdoor storage, especially noticeable during the hot summer months, affecting their effectiveness.
[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention
[0006] The purpose of this invention is to provide a compound polymerization inhibitor, which is prepared by selectively compounding nitroxide radical heterocyclic compounds with reducing agents and phenolic polymerization inhibitors, and using water as a solvent, in order to solve the technical problem that existing nitroxide radical polymerization inhibitors are prone to self-polymerization and decomposition at high temperatures.
[0007] To achieve the above objectives, the present invention provides a compound polymerization inhibitor, comprising one of the following three components combined with water as a solvent, wherein the combination includes:
[0008] Compound type 1, namely component A and component B;
[0009] Compound type 2, namely component A and component C;
[0010] Compound type three, namely component A, component B and component C;
[0011] Component A is a nitrogen-oxygen free radical heterocyclic compound, component B is a reducing agent compound, component C is a phenolic polymerization inhibitor, and the solvent is water.
[0012] Preferably, component A is a nitroxide radical heterocyclic compound with the following structural formula:
[0013]
[0014] Where R is a functional group consisting of hydrogen, hydroxyl, carbonyl, amino, or phosphate ester groups.
[0015] Preferably, component A is selected from one of polymerization inhibitors 701, 702, 705 or 706.
[0016] Preferably, component B is selected from sodium sulfite or sodium dithionite.
[0017] Preferably, component C is p-hydroxyanisole or p-tert-butylcatechol.
[0018] Preferably, the mass ratio of component A to component B in the compound type one is 95-99.99:5-0.01.
[0019] Preferably, the mass ratio of component A to component C in the compound type II is 99-99.99:1-0.01.
[0020] Preferably, the mass ratio of component A, component B and component C in the compound type III is 94-99.98:5-0.01:1-0.01.
[0021] Preferably, the compound polymerization inhibitor is prepared as an aqueous solution with a mass concentration of 5% to 50%.
[0022] Preferably, the compound polymerization inhibitor is prepared by adding at least one of components B and C at the end of the production process of component A according to the mass ratio of the corresponding compound type, mixing, and then granulating or slicing to obtain the compound polymerization inhibitor product.
[0023] Compared with the prior art, the compound polymerization inhibitor of the present invention, when a certain amount of reducing agent or phenolic polymerization inhibitor is added to a nitroxide radical heterocyclic compound or both, has a significant inhibitory effect on the self-polymerization and decomposition of the nitroxide radical heterocyclic compound. Moreover, it plays a synergistic role in the process of use, so that the product of the present invention has better polymerization inhibition effect, better stability at high temperature, and wider application range. Detailed Implementation
[0024] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.
[0025] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.
[0026] This invention utilizes the synergistic effect of a reducing agent and a phenolic polymerization inhibitor. The active NO· radicals in nitroxide-free radical heterocyclic compounds increase their activity at high temperatures, leading to intermolecular self-polymerization into large polymers. Simultaneously, this triggers oxidation / reduction side reactions, causing self-decomposition and ultimately resulting in the precipitation of sediment in the aqueous solution. The reducing agent preferentially eliminates oxidizing species in the system that accelerate the decomposition of nitroxide-free radical heterocyclic compounds and provides electrons to reduce the highly active free radicals into stable groups, thus reducing free radical activity at the source. The phenolic polymerization inhibitor, through the H atom of its phenolic hydroxyl group, captures the NO· radical, converting it into an inactive form, while simultaneously forming stable phenoloxy radicals to block the self-polymerization chain reaction.
[0027] This reduces the possibility of decomposition of nitrogen oxide free radical heterocyclic compounds and terminates the self-polymerization of activated free radicals, ultimately achieving a synergistic effect. This extends the stability time of the compounded product from 25 days to several months, solving the current problem of precipitation at high temperatures.
[0028] Example 1
[0029] Preparation of Compound Type 1: Weigh 1.9 kg of polymerization inhibitor 701, 0.1 kg of sodium sulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0030] Example 2
[0031] Preparation of Compound Type 1: Weigh 1.98 kg of polymerization inhibitor 701, 0.02 kg of sodium sulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0032] Example 3
[0033] Preparation of Compound Type 1: Weigh 1.995 kg of polymerization inhibitor 701, 0.005 kg of sodium sulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0034] Example 4
[0035] Preparation of Compound Type 1: Weigh 1.9 kg of polymerization inhibitor 701, 0.1 kg of sodium hydrosulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0036] Example 5
[0037] Preparation of Compound Type 1: Weigh 1.98 kg of polymerization inhibitor 701, 0.02 kg of sodium hydrosulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0038] Example 6
[0039] Preparation of Compound Type 1: Weigh 1.995 kg of polymerization inhibitor 701, 0.005 kg of sodium hydrosulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0040] Example 7
[0041] Preparation of compound type II: Weigh 1.95 kg of polymerization inhibitor 701, 0.05 kg of p-hydroxyanisole, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0042] Example 8
[0043] Preparation of compound type II: Weigh 1.98 kg of polymerization inhibitor 701 and 0.02 kg of p-hydroxyanisole, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0044] Example 9
[0045] Preparation of compound type II: Weigh 1.995 kg of polymerization inhibitor 701 and 0.005 kg of p-hydroxyanisole, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0046] Example 10
[0047] Preparation of compound type II: Weigh 1.95 kg of polymerization inhibitor 701, 0.05 kg of p-tert-butylcatechol, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0048] Example 11
[0049] Preparation of compound type II: Weigh 1.98 kg of polymerization inhibitor 701, 0.02 kg of p-tert-butylcatechol, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0050] Example 12
[0051] Preparation of compound type II: Weigh 1.995 kg of polymerization inhibitor 701, 0.005 kg of p-tert-butylcatechol, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0052] Example 13
[0053] Preparation of Compound Type III: Weigh 1.88 kg of polymerization inhibitor 701, 0.1 kg of sodium sulfite, and 0.02 kg of p-hydroxyanisole, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0054] Example 14
[0055] Preparation of Compound Type III: Weigh 1.97 kg of polymerization inhibitor 701, 0.02 kg of sodium sulfite, and 0.01 kg of p-hydroxyanisole, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0056] Example 15
[0057] Preparation of Compound Type III: Weigh 1.98 kg of polymerization inhibitor 701, 0.015 kg of sodium sulfite, and 0.005 kg of p-hydroxyanisole, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0058] Example 16
[0059] Preparation of Compound Type 1: Weigh 1.98 kg of polymerization inhibitor 702, 0.02 kg of sodium sulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0060] Example 17
[0061] Preparation of compound type II: Weigh 1.99 kg of polymerization inhibitor 702, 0.01 kg of p-hydroxyanisole, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0062] Example 18
[0063] Preparation of Compound Type III: Weigh 1.97 kg of polymerization inhibitor 702, 0.02 kg of sodium sulfite, and 0.01 kg of p-tert-butylcatechol, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0064] Example 19
[0065] Preparation of Compound Type 1: Weigh 1.995 kg of polymerization inhibitor 705, 0.005 kg of sodium dithionite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0066] Example 20
[0067] Preparation of compound type II: Weigh 1.992 kg of polymerization inhibitor 705, 0.008 kg of p-tert-butylcatechol, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0068] Example 21
[0069] Preparation of Compound Type III: Weigh 1.96 kg of polymerization inhibitor 705, 0.03 kg of sodium dithionite, and 0.01 kg of p-hydroxyanisole, then add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0070] Example 22
[0071] Preparation of Compound Type 1: Weigh 1.95 kg of polymerization inhibitor 706, 0.05 kg of sodium sulfite, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0072] Example 23
[0073] Preparation of compound type II: Weigh 1.998 kg of polymerization inhibitor 706, 0.002 kg of p-hydroxyanisole, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0074] Example 24
[0075] Preparation of Compound Type III: Weigh 1.98 kg of polymerization inhibitor 706, 0.01 kg of sodium sulfite, 0.01 kg of p-tert-butylcatechol, and add 18 kg of pure water to prepare 20 kg of 20% aqueous solution.
[0076] Example 25
[0077] After the synthesis reaction of inhibitor 701 is completed, a compound inhibitor of type III is added to the intermediate product system of inhibitor 701 that has not been purified and dried. The mass ratio of compound inhibitor III (component A: component B: component C = 99:0.5:0.5) is 0.01 kg of sodium sulfite (component B) and 0.01 kg of p-hydroxyanisole (component C) are added to the system. The mixture is stirred and mixed at 30-40°C for 30 minutes. The mixture is then fed into a granulator and spray granulation is performed with an inlet air temperature of 80-90°C and an outlet air temperature of 40-50°C to produce a solid granular compound inhibitor product with a particle size of 0.1-0.5 mm. Alternatively, the mixture can be fed into a slicer and cut into flakes with a thickness of 1-3 mm.
[0078] When using, weigh 2 kg of the above-mentioned compounded polymerization inhibitor product, add 18 kg of pure water, stir to dissolve, and prepare 20 kg of 20% aqueous solution. The compounding ratio is: polymerization inhibitor 701: sodium sulfite: p-hydroxyanisole = 1.98 kg: 0.01 kg: 0.01 kg.
[0079] Comparative Example 1
[0080] Weigh 2 kg of polymerization inhibitor 701, add 18 kg of pure water, and prepare 20 kg of 20% aqueous solution.
[0081] Comparative Example 2
[0082] Weigh 2 kg of polymerization inhibitor 702, add 18 kg of pure water, and prepare 20 kg of 20% aqueous solution.
[0083] Comparative Example 3
[0084] Weigh 2 kg of polymerization inhibitor 705, add 18 kg of pure water, and prepare 20 kg of 20% aqueous solution.
[0085] Comparative Example 4
[0086] Weigh 2 kg of polymerization inhibitor 706, add 18 kg of pure water, and prepare 20 kg of 20% aqueous solution.
[0087] The prepared aqueous solution was placed in a white plastic bucket, the lid was sealed, and the bucket was placed in a drying area, ensuring exposure to sunlight from sunrise to sunset. Experiments verified that the stability of the compounded product was significantly enhanced, especially compound type three, which can meet the requirements of different seasons and environments.
[0088] The results of the extraction time under the following conditions are shown in Table 1.
[0089] Table 1: Results of Extraction Time
[0090]
[0091]
[0092] The compound polymerization inhibitor of this invention is applicable to industrial fields such as oil extraction. The polymerization inhibitor can prevent deposits in oil wells from accumulating and clogging oil pipes and pores, thereby improving oil production efficiency. In the petroleum refining field, it can inhibit polymerization reactions, prevent pipeline and equipment blockage, and improve production efficiency and product quality. In the water treatment field, the polymerization inhibitor can prevent tiny particles in water from accumulating to form scale and sludge, thereby protecting the normal operation of water treatment equipment.
[0093] The purpose of this invention is to improve the polymerization inhibitor of single-type nitrogen oxide free radical heterocyclic compounds and provide a polymerization inhibitor with better thermal stability and stronger scale inhibition and removal effect. It has the advantages of simple synthesis route, cheap and readily available raw materials, low production cost, high efficiency, non-toxicity, simple use method, only a small amount is needed to effectively inhibit polymerization, and no adverse effect on the process.
[0094] The compounded polymerization inhibitor formulated in this invention exhibits better stability and polymerization inhibition effect than when used alone. Furthermore, the solvent used in its formulation is water, which is non-toxic, highly efficient, safe, and environmentally friendly. Therefore, it offers significant economic and social benefits.
[0095] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.
Claims
1. A compound polymerization inhibitor, characterized in that, Composed of one of the following three components in combination with water as a solvent, said combination includes: Compound type 1, namely component A and component B; Compound type 2, namely component A and component C; Compound type three, namely component A, component B and component C; Component A is a nitrogen-oxygen free radical heterocyclic compound, component B is a reducing agent compound, component C is a phenolic polymerization inhibitor, and the solvent is water.
2. The compound polymerization inhibitor according to claim 1, characterized in that, Component A is a nitrogen-oxygen radical heterocyclic compound with the following structural formula: Where R is a functional group consisting of hydrogen, hydroxyl, carbonyl, amino, or phosphate ester groups.
3. The compound polymerization inhibitor according to claim 2, characterized in that, Component A is selected from one of polymerization inhibitors 701, 702, 705 or 706.
4. The compound polymerization inhibitor according to claim 1, characterized in that, Component B is selected from either sodium sulfite or sodium dithionite.
5. The compound polymerization inhibitor according to claim 1, characterized in that, Component C is selected from p-hydroxyanisole or p-tert-butylcatechol.
6. The compound polymerization inhibitor according to claim 1, characterized in that, The mass ratio of component A to component B in the compound type I is 95-99.99:5-0.
01.
7. The compound polymerization inhibitor according to claim 1, characterized in that, The mass ratio of component A to component C in the compound type II is 99-99.99:1-0.
01.
8. The compound polymerization inhibitor according to claim 1, characterized in that, The mass ratio of components A, B and C in the compound type III is 94-99.98:5-0.01:1-0.
01.
9. The compound polymerization inhibitor according to claim 1, characterized in that, The compound polymerization inhibitor is prepared as an aqueous solution with a mass concentration of 5% to 50%.
10. The compound polymerization inhibitor according to claim 1, characterized in that, The preparation method of the compound polymerization inhibitor is as follows: at the end of the production process of component A, at least one of component B and component C is added according to the mass ratio of the corresponding compound type, and after mixing, it is granulated or sliced to obtain the compound polymerization inhibitor product.