KR-20260066089-A - polymerization inhibitor

Abstract

The present invention relates to a mixture comprising at least one 1,2,3,4-tetrahydroquinoxaline and at least one polymerizable carbonyl compound.

Inventors

• 고르게스 얀 니클라스
• 벨츠 올리버
• 살터 라이너
• 플라이쉬하커 프리데리케
• 마르틴 프리드리흐-게오르그
• 라인 크리스티안

Assignees

• 바스프 에스이

Dates

Publication Date

20260512

Application Date

20240826

Priority Date

20230905

Claims (15)

1. At least one compound of the following general formula (I) or the following general formula (II), and At least one polymerizable carbonyl compound A mixture comprising, wherein the total content of polymerizable carbonyl compounds in the mixture is at least 30% by weight based on the total weight of the mixture: (I) In the above formula, R1 , R2 , R3 , and R4 are independently H, C1 - C20 alkyl, C1 - C20 acyl, C1 - C20 acyloxy, C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, nitro, cyano, amino, or halide, and R5 is H, C1 - C20 alkyl, C1 - C20 acyl, or aryl, and R6 , R7 , R8 , and R9 are independently H, C1 - C20 alkyl, C1 - C20 acyl, C1 - C20 acyloxy, C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, or halide, and R 10 is H, C 1 -C 20 alkyl, C 1 -C 20 acyl, or aryl; (II) In the above formula, R11 , R12 , R13 , and R14 are independently H, C1 - C20 alkyl, C1 - C20 acyl, C1 - C20 acyloxy, C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, nitro, cyano, amino, or halide, and R 15 is H, C 1 -C 20 alkyl, C 1 -C 20 acyl, or aryl, and R16 and R17 are independently H, C1 - C20 alkyl, C1 - C20 acyl, C1 - C20 acyloxy, C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, or halide and R 18 is H, C 1 -C 20 alkyl, C 1 -C 20 acyl, or aryl.
2. In paragraph 1, R1 , R2 , R3 , and R4 are independently H, C1 - C10 alkyl, C1 - C10 alkoxy, hydroxy, or halide; R5 is H or C1 - C10 alkyl; R6 , R7 , R8 , and R9 are independently H, C1 - C10 alkyl, C1 - C10 alkoxy, hydroxy, or halide; R10 is H or C1 - C10 alkyl; R11 , R12 , R13 , and R14 are independently H, C1 - C10 alkyl, C1 - C10 alkoxy, hydroxy, or halide; R15 is H or C1 - C10 alkyl; and R16 and R17 are independently H, C1 A mixture in which -C10 alkyl, C1 - C10 alkoxy, hydroxy or halide is present, and R18 is H or C1 - C10 alkyl.
3. In paragraph 1, R1 , R2 , R3, and R4 are independently H, C1 - C6 alkyl or C1 - C6 alkoxy, R5 is H or C1 - C6 alkyl, R6 , R7 , R8 , and R9 are independently H, C1 - C6 alkyl or C1 - C6 alkoxy, R10 is H or C1 - C6 alkyl, R11 , R12 , R13 , and R14 are independently H, C1 - C6 alkyl or C1 - C6 alkoxy, R15 is H or C1 -C6 alkyl, R16 and R17 are H, C1 - C6 alkyl or C1 -C6 alkoxy , and R18 is H, C1 - C6 Alkyl, mixture.
4. In paragraph 1, R1 , R2 , R3, and R4 are independently H, C1 - C4 alkyl or C1 - C4 alkoxy; R5 is H or C1 - C3 alkyl; R6 , R7 , R8 , and R9 are independently H, C1 -C4 alkyl or C1 - C4 alkoxy; R10 is H or C1 - C3 alkyl; R11 , R12 , R13 , and R14 are independently H, C1 - C4 alkyl or C1 -C4 alkoxy ; R15 is H or C1 - C3 alkyl; R16 and R17 are independently H, C1 - C4 alkyl or C1 - C4 alkoxy; and R18 is H or C1 -C 3. Alkyl, mixture.
5. In paragraph 1, The compound of general formula (I) is 7-methoxy-1,3,3-trimethyl-1,2,3,4-tetrahydroquinoxaline, 6-methoxy-1,3,3-trimethyl-1,2,3,4-tetrahydroquinoxaline, 6-methoxy-1,2,3,4-tetramethyl-1,2,3,4-tetrahydroquinoxaline or 7-methoxy-1,2,2,4-tetramethyl-1,2,3,4-tetrahydroquinoxaline; A mixture of compounds of general formula (II), which is 3,3-dimethyl-3,4-dihydroquinoxalin-2(1H)-one, 7-methoxy-3,3-dimethyl-3,4-dihydroquinoxalin-2(1H)-one, 6-methoxy-3,3-dimethyl-3,4-dihydroquinoxalin-2(H1)-one, 7-methoxy-1,3,3-trimethyl-3,4-dihydroquinoxalin-2(1H)-one or 6-methoxy-1,3,3-trimethyl-2,3-dihydroquinoxalin-2(1H)-one.
6. In any one of paragraphs 1 through 5, A mixture in which the total amount of the compound of general formula (I) or (II) in the mixture is 0.0001% to 0.1000% by weight based on the total amount of polymerizable carbonyl compounds.
7. In any one of paragraphs 1 through 6, A mixture in which the total amount of polymerizable carbonyl compounds in the mixture is at least 98% by weight based on the total amount of the mixture.
8. In any one of paragraphs 1 through 7, A mixture in which the polymerizable carbonyl compound is acrylic acid and/or methacrylic acid.
9. In paragraph 8, A mixture in which the total amount of the compound of general formula (I) or (II) in the mixture is 0.0050 wt% to 0.1000 wt% based on the total amount of acrylic acid and/or methacrylic acid.
10. In any one of paragraphs 1 through 7, A mixture of polymerizable carbonyl compounds, which are methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate and/or 2-ethylhexyl acrylate.
11. In Paragraph 10, A compound in which the total amount of the compound of general formula (I) or (II) in the mixture is 0.0001 wt% to 0.0100 wt% based on the total amount of methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate and/or 2-ethylhexyl acrylate.
12. Use of at least one compound of general formula (I) or (II) according to any one of claims 1 to 5 for inhibiting the polymerization of at least one carbonyl compound.
13. A method for storing and/or transporting a mixture according to any one of claims 1 to 11.
14. Compound of the following general formula (I): (I) In the above formula, R1 , R2 , R3 , and R4 are independently H, C1 - C20 alkyl, C1 - C20 acyl, C1 - C20 acyloxy, C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, nitro, cyano, amino, or halide, wherein at least one of R1 , R2 , R3 , and R4 is not H, R5 is a C1 - C20 alkyl, C1 - C20 acyl, or aryl, and R6 and R7 are independently C1 - C20 alkyl and R8 and R9 are independently H, C1 -C20 alkyl, C1- C20 acyl, C1 - C20 acyloxy, C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, or halide, or R6 and R7 are independently H, C1-C20 alkyl , C1 - C20 acyl , C1 -C20 acyloxy , C1 - C20 alkoxy, aryl, aryloxy, benzyl, hydroxy, or halide, and R8 and R9 are independently C1 - C20 alkyl, and R 10 is a C 1 -C 20 alkyl, C 1 -C 20 acyl, or aryl.
15. In Paragraph 14, A compound in which R1 , R2 and R4 are H, R3 is methoxy, R5 is methyl, R6 and R7 are H, R8 and R9 are methyl, and R10 is methyl.

Description

polymerization inhibitor The present invention relates to a mixture comprising at least one substituted 1,2,3,4-tetrahydroquinoxaline and at least one polymerizable carbonyl compound. Chemical compounds containing one or more ethylene-type unsaturated groups tend to undergo free radical polymerization. Therefore, these compounds are also referred to as polymerizable compounds. This tendency toward free radical polymerization implies that these compounds can be used as monomers in the formation of polymers. However, this tendency has the disadvantage that it can lead to undesirable continuous free radical polymerization during storage and transport processes, as well as during chemical and physical processes such as distillation and rectification, which may occur under the influence of energy, particularly heat and/or light. Such uncontrolled polymerization can lead to the gradual formation of polymer residues, for example, on heated surfaces, which require removal and often result in short operating times. Uncontrolled polymerization can also proceed explosively. Therefore, during the storage, transport, and chemical/physical processing of ethylene-type unsaturated compounds or mixtures composed of such compounds that have a tendency for free radical polymerization, compounds that prevent or at least delay undesirable continuous free radical polymerization are conventionally added. Such substances are called polymerization inhibitors. Polymerization inhibitors can be used in the form of individual chemical compounds or mixtures of compounds. Polymerization inhibitors require specific conditions depending on the application. For polymerization inhibitors suitable as stabilizers for ethylene-type unsaturated compounds during transport and/or storage, it is important whether the efficiency of the polymerization inhibitor (i.e., the degree of inhibition of polymerization) can be controlled. In the storage and/or transport environment of ethylene-type unsaturated compounds, the polymerization inhibitor must adequately prevent or delay undesirable continuous free radical polymerization, while allowing the desired free radical polymerization of the ethylene-type unsaturated compound under appropriate polymerization conditions without the preferential separation of the polymerization inhibitor used during storage and/or transport. It is important that if the stabilizer used for the desired polymerization is not separated during storage and/or transport, this does not have negative effects, such as acting as an unintended chain transfer agent. In terms of international production scale, acrylic acid is undoubtedly one of the most important ethylene-type unsaturated compounds. During storage and/or transport, acrylic acid is generally stabilized against unwanted spontaneous free radical polymerization by hydroquinone monomethyl ether (MEHQ) at a concentration of 0.018% to 0.022% by weight of acrylic acid. For sufficient stabilization of acrylic acid against unwanted spontaneous free radical polymerization using MEHQ, it is essential that a sufficient amount of oxygen be dissolved in the acrylic acid. When acrylic acid is stored and/or transported under an atmosphere containing 5% to 21% oxygen by volume, a sufficient amount of oxygen is generally dissolved in the acrylic acid. At the desired polymerization of acrylic acid, the amount of dissolved oxygen in the acrylic acid is reduced, so that the efficiency of MEHQ as a polymerization inhibitor is sufficiently reduced to the extent that acrylic acid polymerizes even in the presence of MEHQ. MEHQ is used not only as a polymerization inhibitor for the storage and/or transport of acrylic acid, but also as a polymerization inhibitor for the storage and/or transport of methacrylic acid, acrylic acid esters and/or methacrylic acid esters, or mixtures containing one or more of these compounds. Due to the wide range of uses of MEHQ, it is one of the most important storage and/or transport stabilizers for polymerizable compounds, particularly acrylic acid, methacrylic acid, acrylic acid esters, and methacrylic acid esters. The polymerizable compound is stored in a suitable permanent installation container, such as a storage tank or other storage vessel (e.g., see Acrylic Acid, A Summary of Safety and Handling, 4th edition 2013, 7 Bulk Storage Facilities and Accessories). It is preferable that the polymerizable compound be stored in each container for at least 1 minute, more preferable that it be stored for at least 10 minutes, and particularly preferable that it be stored for at least 60 minutes. It is preferable that the polymerizable compound be stored in each container for no more than 180 days, more preferable that it be stored for no more than 90 days, and particularly preferable that it be stored for no more than 30 days. The particularly preferred range is derived by freely combining the previously mentioned lower and upper limits. Polymerizable compounds are typically