JP2002533309A - Compositions and methods for preventing radical polymerization of ethylenically unsaturated aliphatic monomers - Google Patents

Abstract

(57) Abstract: The present invention is a composition for preventing radical polymerization of an ethylenically unsaturated aliphatic monomer, comprising at least one diphenylamine derivative represented by the general formula (I), In the formula, A and B represent a group consisting of a ring that forms the whole or a part of a carbocyclic, aromatic, monocyclic or polycyclic ring system, and R ₁ and R ₂ are the same. Or a different group, and represents a hydrogen atom or one or more substituents, wherein n + m represents 1 or more, and n and m represent the number of substituents on a ring.

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a composition for use as a radical polymerization inhibitor for ethylenically unsaturated aliphatic monomers, and to prevent radical polymerization when industrially preparing such unsaturated monomers. About the method. More particularly, the present invention relates to vinyl aliphatic monomers.

[0002] US Pat. No. 3,959,358 uses p-hydroxydiphenylamine to
It states that it is possible to prevent the polymerization of acrylic esters.

[0003] US Pat. No. 4,692,544 also discloses that p-phenylenediamine derivatives can be used to prevent the polymerization of ethylenically unsaturated monomers and that 4,4′-diaminodiphenylamine gives the best results. It has said.

[0004] An inhibitor of improved properties has now been found which is superior to conventionally used inhibitors, especially hydroquinone.

More specifically, the present invention relates to a composition for preventing radical polymerization of ethylenically unsaturated aliphatic monomers, comprising at least one diphenylamine derivative of the formula (I) ,

[0006]

Embedded image In formula (I), A and B represent ring residues forming all or part of a carbocyclic, aromatic, monocyclic or polycyclic ring system; R ₁ and R ₂ May be the same or different and represent a hydrogen atom or one or more substituents, wherein n + m is 1 or more, and n and m represent the number of substituents on the ring Composition.

The protective effect of the defined diphenylamine derivatives is enhanced when said derivatives having at least one hydroxyl group on one ring further comprise at least one substituent on one ring. It has been found that the substituents can be substituents such as R ₁ and / or R ₂ , in particular further hydroxyl groups.

[0008] Accordingly, a first class of inhibitors of the present invention is of the hydroxydiphenylamine type, which contains at least one substituent in addition to the hydroxyl group.

Another class of inhibitors of the present invention is of the dihydroxydiphenylamine type, which can include other substituents on the ring.

As a variant, the invention consists in combining the diphenylamine derivatives according to the invention with further polymerization inhibitors.

More specifically, the diphenylamine derivative of the present invention is represented by the general formula (I), wherein A and B represent one of the following rings.

[0012]

Embedded image In a preferred compound, A and B are the same and represent a benzene ring.

One of ring A and ring B has at least one substituent in addition to the hydroxyl group. Note that m is at least 1 if n is equal to 0, and that n is at least 1 if m is equal to 0.

The number of substituents on rings A and B can be different.

Therefore, n is 3 or less, preferably 0 or 1.

With respect to m, m is 4 or less, preferably 1 or 2.

Residues A and B can optionally have one or more substituents represented by the symbols R ₁ and R ₂ in formula (1). Preferred meanings are given below.

A straight chain containing 1 to 12, preferably 1 to 4 carbon atoms, such as a hydrogen atom, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl or tertiary butyl, Linear or branched alkenyl groups containing 2 to 6, preferably 2 to 4, carbon atoms, such as branched alkyl groups, vinyl or allyl, methoxy, ethoxy, propoxy, isopropoxy, butoxy, etc. 1 to 6
Or preferably a straight-chain or branched alkoxy or thioether group containing from 1 to 4 carbon atoms, or an alkenyloxy group, preferably an allyloxy or phenoxy group, or the following formula: —R ₃ —OH, —R _{3 -SH, -R 3 -COOR 4, -R} 3 -CO-R 4, -R 3 -N (R 4) 2, -R 3 -CO-N (R 4) 2, -R 3 -NH-CO _{-R 4, -R 3 -NH-COO} -R 4, a group represented by, in the above equation, _{R 3} is a covalent bond, or a methylene, ethylene, propylene,
Represents a straight-chain or branched, saturated or unsaturated divalent hydrocarbon radical having 1 to 6 carbon atoms, such as isopropylene or isopropylidene, and the radical R ₄ is
It may be the same or different and represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms.

One particularly preferred diphenylamine derivative of the formula (I) is represented by the formula (Ia)
) Is a diphenylamine derivative.

[0020]

Embedded image In formula (Ia), R ₁ , R ₂ , n and m have the meanings given above.

Preferred compounds of formula (Ia) are those wherein R _{1 in} formula (I) represents a hydrogen atom, an alkyl or alkoxy group containing from 1 to 4 carbon atoms, and R ₂ represents a hydrogen atom, or Compounds representing alkyl or alkoxy groups containing from 1 to 4 carbon atoms.

Preferred compounds are those of formula (Ia) wherein n is 0 and m is 1.

The examples given below illustrate preferred diphenylamine derivatives. More specifically, preferred diphenylamine derivatives are selected from:

2-hydroxy-5-methyldiphenylamine, 2-hydroxy-4-methyldiphenylamine, 2-hydroxy-4 ′, 5-dimethyldiphenylamine, 2,2′-dihydroxydiphenylamine, 3-hydroxy-4′-methoxydiphenylamine 3,3′-dihydroxy-2,2′-dimethyldiphenylamine, 3,3′-dihydroxy-2,2′-dimethoxydiphenylamine, 4-hydroxy-4′-methyldiphenylamine, 4-hydroxy-4 ′ (methoxycarbonyl Amino) -diphenylamine, N- (4-hydroxyphenyl) -2-naphthylamine, 4,4′-dihydroxydiphenylamine, 4,4′-dihydroxy-2,2′-dimethyldiphenylamine, 4,4′-dihydroxy-2, 2 It is also possible to use a mixture of '-dimethoxydiphenylamine, 2-hydroxy-4'-hydroxydiphenylamine and diphenylamine derivatives.

Preferred derivatives of the invention are of the dihydroxydiphenylamine type,
More specifically, they are 4,4'-dihydroxydiphenylamine, 2,2'-dihydroxydiphenylamine, and 2-hydroxy-4'-hydroxydiphenylamine.

The compositions according to the invention comprising at least one diphenylamine derivative having the formula (Ia) constitute a particularly preferred embodiment of the invention.

The compositions of the present invention are suitable for stabilizing aliphatic monomers having at least one ethylenically unsaturated bond.

More specifically, ethylenically unsaturated monomers are olefin monomers having one or more unsaturated bonds, such as isoprene or butadiene; vinyl chloride, chloroprene, vinylidene chloride, vinylidene fluoride, or vinyl fluoride type. Unsaturated halogenated monomers; unsaturated acids of the acrylic, methacrylic, or crotonic acid type; unsaturated esters, especially methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate Or unsaturated acrylates of hydroxypropyl acrylate type; unsaturated methacrylate esters of methyl methacrylate, butyl methacrylate, lauryl methacrylate, dimethylaminoethyl methacrylate, or stearyl methacrylate type;
Vinyl acetate; unsaturated resins such as epoxy acrylate resin and polyethylene glycol diacrylate; acrylamide, N, N-dimethylacrylamide,
Unsaturated amides such as methylenebisacrylamide or N-vinylpyrrolidone; unsaturated nitriles of the acrylonitrile type; unsaturated ethers such as vinyl ether or methyl ether; and diethyl vinyl phosphonate. It is to be understood that this list is not exhaustive and that the present invention relates to general materials that stabilize any type of ethylenically unsaturated aliphatic monomer.

However, the compositions of the present invention are particularly effective when stabilizing ethylenically unsaturated aliphatic monomers such as acrylates or methacrylates.

[0030] The compositions of the present invention form either a true solution, that is, one composed of completely mixed ingredients, or an emulsion or suspension. However, in a preferred embodiment, the composition is in the form of a true solution in the monomers themselves.

In a variant, the composition of the present invention comprises hydroquinone, p-methoxyphenol; phenothiazine; tetramethylpiperidine-N-oxyl (TEMPO);
Nitroxide-type compounds such as 4-hydroxytetramethylpiperidine-N-oxyl and 4-oxotetramethylpiperidine-N-oxyl; imidaline / imidazoline-N-oxyl compounds described in French Patent Application No. 97/04230, preferably Is 2,2,3,4,5,5-hexamethylimidazolidine-1
Making the other polymerization inhibitors, such as oxyl, or any other known inhibitor, compatible with the other components of the composition under the operating conditions to which the monomers to be stabilized are exposed. If so, it can be contained.

Some of the diphenylamine derivatives of the formula (I) are commercially available. Others are readily prepared by technicians from commercially available products.

The present invention also relates to acids for preventing radical polymerization of ethylenically unsaturated aliphatic monomers, preferably vinyl aliphatic monomers, from taking place. The method comprises, for example, adding an effective amount of the composition of the invention as defined above to the monomer.

The amount of diphenylamine derivative added for effective polymerization prevention can vary over a wide range. It depends on the monomers to be stabilized and the operating conditions to which the monomers are exposed. Obviously, at higher temperatures, large amounts of inhibitor will be used. The method of the present invention can be used to stabilize monomers during production and purification. Often, purification is performed by distilling the monomers, and the temperature of the reboiler can exceed 120 ° C.

The ideal amount of inhibitor must be evaluated on a case-by-case basis.

Whatever the amount may be, a generally sufficient measure of the total amount of the diphenylamine derivative is in the range 1 to 2000 ppm, preferably in the range 5 to 1000 ppm. This amount is expressed relative to the total weight of the monomers to be stabilized.

As indicated above, one or more known polymerization inhibitors can be added to the monomer.

The ratio of the polymerization inhibitor is such that the ratio of the total weight of the diphenylamine type component represented by the formula (I) to the total weight of all the components is in the range of 90/10 to 10/90, preferably 80/90. It is preferred that it is in the range of 20-20 / 80.

The diphenylamine derivatives of the present invention can be added to the monomers in a conventional manner, optionally in combination with conventional polymerization inhibitors. In the case of distillation, the place of introduction can vary widely, and each compound is transferred to a heat exchanger, piping, pump, reboiler,
It can be added to a compressor or, more generally, to a distillation column. It is to be understood that the addition can be carried out continuously or batchwise at one location or at a different specific location.

According to the invention, it is conceivable to add the inhibitors according to the invention and also further inhibitors simultaneously or separately.

The present invention also encompasses using the diphenylamine derivatives of the present invention to stabilize the monomers in storage by adding a small amount equal to the amount mentioned above. The present invention also includes admixing with other inhibitors.

The process of the invention is particularly advantageous in that it is effective in preventing the radical polymerization of vinyl aliphatic monomers, especially acrylates and methacrylates.

The composition of the present invention is advantageously used as an emergency inhibitor during the synthesis of polymers from ethylenically unsaturated aliphatic monomers.

The following examples are given by way of illustration and relate to preferred embodiments of the present invention.

EXAMPLES For the radical polymerization of unsaturated aliphatic monomers, a protection test was carried out using methyl methacrylate using the following operating protocol in order to evaluate the protection properties of the products according to the invention.

The effectiveness of the inhibitors according to the invention (or an inhibitor mixture comprising at least one inhibitor according to the invention) on methyl methacrylate was determined by measuring the induction period. This induction period represents the period during which the monomer starts to polymerize after the period when the monomer is heated in a temperature controlled bath in the presence of a polymerization initiator. This period was measured by the slight exotherm of the sample considered.

Measurements were taken on a laboratory calorimeter, the time and temperature were recorded and processed by a microcomputer.

Methyl methacrylate (M) destabilized by passing through an activated alumina column and completely removing p-methoxyphenol (the first stabilizer) from the medium
The test was performed using MA).

20 ml of MMA with 100 ppm of azobisisobutyronitrile (AIBN), which was re-stabilized with 20 ppm of test inhibitor, was added to the test tube. The test tube was immersed in a bath with an incubator at 80 ° C., and the temperature difference between this sample and a reference test tube containing silicone oil was continuously recorded. The induction period Ti corresponded to a visible exotherm indicating the initiation of MMA polymerization. A plot of T against time was recorded continuously. At constant concentration by weight, the longer the induction period, the more effective the test inhibitor.

Table (I) below shows the induction periods of some conventional (meth) acrylate inhibitors.

[0051]

[Table 1]

Examples 1-9 The operating protocol described above was repeated for each polymerization inhibitor.

Table (II) summarizes the results obtained for the induction periods of the different inhibitors according to the invention.

[0054]

[Table 2]

The induction period is currently one of the (meth) acrylate industry's best commercial inhibitors,
Better or comparable to the induction period of hydroquinone.

Comparative Tests 10 and 11 The operating protocol described above was repeated using unsubstituted hydroxydiphenylamine type compounds.

The results are shown in Table (III).

[0058]

[Table 3]

Comparison of Examples 1 to 3 with Comparative Example 10 shows that the induction period can be increased by the presence of a methyl or hydroxyl substituent.

The same is true when comparing Comparative Example 11 with Examples 4 to 7.

The same is true when comparing Example 8 with the two Comparative Examples 10 and 11.

Examples 12 to 15 These examples describe the diphenylamines of the invention of Examples 5, 4, 6, and 2 in combination with a further inhibitor, namely hydroquinone.

The following were used in the tests: 20ml of MMA + AIBN 100pp
m + inhibitor mixture (hydroquinone (HQ) 10 ppm + inhibitor of the present invention 10 pp)
m).

Table (IV) summarizes the results obtained for the induction period of the inhibitor mixture according to the invention.

[0065]

[Table 4] The results were better than using the 20 ppm product alone.

Example 16 This example illustrates the use of the diphenylamine of the present invention of Example 2 in addition to another inhibitor,
That is, what is combined with TEMPO is described.

The following were used in the tests: 20ml of MMA + AIBN 100pp
m + inhibitor mixture (TEMPO 10 ppm + inhibitor of the invention 10 ppm).

Table (V) summarizes the results obtained for the induction period of the inhibitor mixture according to the invention.

[0069]

[Table 5]

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CR, CU, CZ, DE, DK, DM, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID , IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZW

Claims (24)

[Claims] 1. A composition for preventing radical polymerization of an ethylenically unsaturated aliphatic monomer, comprising a compound represented by the general formula (I): Wherein A and B each represent a residue of a ring forming the whole or a part of a carbocyclic, aromatic, monocyclic, or polycyclic ring system, and R ₁ and R ₂ are They may be the same or different and represent a hydrogen atom or one or more substituents, wherein n + m is 1 or more, and n and m represent the number of substituents on the ring. ] The composition which contains at least 1 type of diphenylamine derivative represented by these. 2. The diphenylamine derivative is represented by the formula (I), wherein A and B represent a benzene ring or a naphthalene ring, and preferably, A and B are the same and represent a benzene ring. The composition of claim 1. 3. The diphenylamine derivative is represented by the formula (I), wherein n is 3
The composition according to claim 1, wherein m is 4 or less, preferably 1 or 2, below, preferably 0 or 1. 4. A diphenylamine derivative represented by the formula (I), wherein R ₁ and R ₂ are a hydrogen atom, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, or tertiary. Straight or branched chain alkyl groups containing 1 to 12, preferably 1 to 4 carbon atoms, such as butyl, 2 to 6, preferably 2 to 4 carbon atoms, such as vinyl or allyl; Containing straight or branched alkenyl groups, methoxy, ethoxy, propoxy, isopropoxy, butoxy, etc., from 1 to 6
Pieces, preferably straight-chain or branched alkoxy or thioether groups containing from 1 to 4 carbon atoms or an alkenyloxy group preferably allyloxy, or phenoxy group, or the formula,: -R 3 _-OH, -R _{3 -SH, -R 3 -COOR 4,} -R 3 -CO-R 4, -R 3 -N (R 4) 2, -R 3 -CO-N (R 4) 2, -R 3 -NH- CO—R ₄ , —R ₃ —NH—COO—R ₄ , wherein R ₃ is a covalent bond or methylene, ethylene, propylene, isopropylene, or isopropylidene; Represents a straight-chain or branched, saturated or unsaturated divalent hydrocarbon group having 1 to 6 carbon atoms, wherein the groups R ₄ may be the same or different and include a hydrogen atom, or 1 to 6 Carbon Characterized in that represents a linear or branched alkyl radical having children, the composition according to any one of claims 1 to 3. 5. A diphenylamine derivative represented by the formula (Ia): 5. A method according to claim ₁ , wherein in formula (Ia), R ₁ , R ₂ , n and m have the meaning given in any one of claims 1 to 4 above. A composition according to claim 1. 6. A diphenylamine derivative represented by the formula (Ia), wherein R ₁ represents a hydrogen atom or an alkyl or alkoxy group containing 1 to 4 carbon atoms, and R ₂ represents a hydrogen atom, or Composition according to claim 5, characterized in that it represents an alkyl or alkoxy group containing 1 to 4 carbon atoms. 7. The composition according to claim 1, wherein the composition is 2-hydroxy-5-methyldiphenylamine, 2-hydroxy-4-methyldiphenylamine, 2-hydroxy-4 ′, 5-dimethyldiphenylamine, 2,2′-dihydroxydiphenylamine, 3-hydroxy -4'-methoxydiphenylamine, 3,3'-dihydroxy-2,2'-dimethyldiphenylamine, 3,3'-dihydroxy-2,2'-dimethoxydiphenylamine, 4-hydroxy-4'-methyldiphenylamine, 4-hydroxy -4 '(methoxycarbonylamino) -diphenylamine, N- (4-hydroxyphenyl) -2-naphthylamine, 4,4'-dihydroxydiphenylamine, 4,4'-dihydroxy-2,2'-dimethyldiphenylamine, 4,4 '-Dihydroxy-2,2'-dimethyl The composition according to claim 1, comprising a diphenylamine derivative selected from toxicdiphenylamine and 2-hydroxy-4′-hydroxydiphenylamine. 8. The method according to claim 1, further comprising another polymerization inhibitor.
A composition according to any one of claims 1 to 7. 9. The polymerization inhibitor is selected from the group consisting of hydroquinone; p-methoxyphenol; phenothiazine; tetramethylpiperidine-N-oxyl, 4-hydroxytetramethylpiperidine-N-oxyl, 4-oxotetramethylpiperidine-N-oxyl and the like. Nitroxide type compounds; imidaline / imidazoline-N-oxyl compounds, preferably 2,2,3,4,5,5-hexamethylimidazolidin-1
9. The composition according to claim 8, characterized in that it is -oxyl or any other known inhibitor. 10. The composition according to claim 8, wherein the polymerization inhibitor is hydroquinone or phenothiazine. 11. The amount of the polymerization inhibitor is such that the ratio of the total weight of the diphenylamine type component having the formula (I) to the total weight of the components is in the range 90/10 to 10/90, preferably 80/20 to 20. A composition according to any one of claims 9 or 10, characterized in that it is in the range of / 80. 12. A method for preventing radical polymerization of an ethylenically unsaturated aliphatic monomer, comprising adding an effective amount of at least one diphenylamine derivative represented by the general formula (I) to said monomer. Including In formula (I), A and B represent ring residues forming all or part of a carbocyclic, aromatic, monocyclic or polycyclic ring system; R ₁ and R ₂ May be the same or different and represents a hydrogen atom or one or more substituents; n + m is 1 or more; and n and m represent the number of substituents on a ring. 13. The diphenylamine derivative is represented by the formula (I), wherein A and B represent a benzene ring or a naphthalene ring, and preferably, A and B are the same and represent a benzene ring. The method of claim 12, wherein: 14. The diphenylamine derivative is represented by the formula (I), wherein n is 3 or less, preferably 0 or 1, and m is 4 or less, preferably 1 or 2
13. The method according to claim 12, wherein 15. A diphenylamine derivative represented by the formula (I), wherein R ₁ and R ₂ are a hydrogen atom, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, or tertiary. Straight or branched chain alkyl groups containing 1 to 12, preferably 1 to 4 carbon atoms, such as butyl, 2 to 6, preferably 2 to 4 carbon atoms, such as vinyl or allyl; Containing straight or branched alkenyl groups, methoxy, ethoxy, propoxy, isopropoxy, butoxy, etc., from 1 to 6
Pieces, preferably straight-chain or branched alkoxy or thioether groups containing from 1 to 4 carbon atoms or an alkenyloxy group preferably allyloxy, or phenoxy group, or the formula,: -R 3 _-OH, -R _{3 -SH, -R 3 -COOR 4,} -R 3 -CO-R 4, -R 3 -N (R 4) 2, -R 3 -CO-N (R 4) 2, -R 3 -NH- CO—R ₄ , —R ₃ —NH—COO—R ₄ , wherein R ₃ is a covalent bond or methylene, ethylene, propylene, isopropylene, or isopropylidene; Represents a straight-chain or branched, saturated or unsaturated divalent hydrocarbon group having 1 to 6 carbon atoms, wherein the groups R ₄ may be the same or different and include a hydrogen atom, or 1 to 6 Carbon Characterized in that it represents a linear or branched alkyl radical having children, the method according to any one of claims 12 to 14. 16. A diphenylamine derivative represented by the formula (Ia): 16. Formula (Ia), wherein R ₁ , R ₂ , n and m have the meaning given in any one of claims 12 to 15 above, characterized in that: The method according to claim 1. 17. The diphenylamine derivative is represented by the formula (Ia): ₁ Is a hydrogen atom or an alkyl or alkoxy containing 1 to 4 carbon atoms
Represents a group, R₂Is a hydrogen atom or an alkyl containing 1 to 4 carbon atoms
17. A method according to claim 16, characterized in that it represents an alkoxy group. 18. The diphenylamine derivative is 2-hydroxy-5-methyldiphenylamine, 2-hydroxy-4-methyldiphenylamine, 2-hydroxy-4 ′, 5-dimethyldiphenylamine, 2,2′-dihydroxydiphenylamine, 3-hydroxy -4'-methoxydiphenylamine, 3,3'-dihydroxy-2,2'-dimethyldiphenylamine, 3,3'-dihydroxy-2,2'-dimethoxydiphenylamine, 4-hydroxy-4'-methyldiphenylamine, 4-hydroxy -4 '(methoxycarbonylamino) -diphenylamine, N- (4-hydroxyphenyl) -2-naphthylamine, 4,4'-dihydroxydiphenylamine, 4,4'-dihydroxy-2,2'-dimethyldiphenylamine, 4,4 '-Dihydro 18. A method according to claim 12, characterized in that it is selected from: 2,2'-dimethoxydiphenylamine, 2-hydroxy-4'-hydroxydiphenylamine 4,4'-dihydroxy-2,2'-dimethyldiphenylamine. A method according to any one of the preceding claims. 19. The total amount of the diphenylamine derivative represented by the formula (I) to be added is in the range of 1 to 2000 ppm, preferably in the range of 5 to 1000 ppm based on the total weight of the monomer. Claims 12 to 18
The method according to any one of the preceding claims. 20. The amount of the polymerization inhibitor, wherein the ratio of the total weight of the diphenylamine type component represented by the formula (I) to the total weight of the components is in the range of 90/10 to 10/90, preferably 80/20. 20. A method according to any one of claims 12 to 19, characterized in that it is in the range of ~ 20/80. 21. The said ethylenically unsaturated aliphatic monomer is an olefin monomer having one or two unsaturated bonds, an unsaturated halogenated monomer, an unsaturated acid, an unsaturated ester, an unsaturated resin, an unsaturated amide. 21. The process according to any one of claims 12 to 20, characterized in that it is selected from: unsaturated nitriles, and unsaturated ethers. 22. The ethylenically unsaturated aliphatic monomer is isoprene and butadiene; vinyl chloride, chloroprene, vinylidene chloride, vinylidene fluoride, or vinyl fluoride; acrylic acid, methacrylic acid, and crotonic acid; methyl acrylate; Ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, or hydroxypropyl acrylate unsaturated esters of acrylic acid; methyl methacrylate, butyl methacrylate;
Lauryl methacrylate, dimethylaminoethyl methacrylate, or stearyl methacrylate type unsaturated methacrylic acid ester; vinyl acetate; epoxy acrylate resin and polyethylene glycol diacrylate; acrylamide;
22. The method according to claim 21, characterized in that it is selected from N-dimethylacrylamide, methylenebisacrylamide and N-vinylpyrrolidone; acrylonitrile; vinyl ethers and methyl ethers; and diethylvinylphosphonate. 23. The method according to claim 22, wherein the aliphatic monomer is an acrylate or a methacrylate. 24. Use of a composition according to any one of claims 1 to 11 as an emergency inhibitor during the synthesis of a polymer using an ethylenically unsaturated aliphatic monomer.