CN119285813A - A polymerization inhibitor for butadiene unsaturated olefin polymerization and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of polymerization inhibitors, and discloses a polymerization inhibitor for butadiene unsaturated olefin polymerization and a preparation method thereof, comprising 10-30 parts by weight of a main polymerization inhibitor, 1-5 parts by weight of an antioxidant, 1-5 parts by weight of diethylhydroxylamine, 20-40 parts by weight of diethylene glycol butyl ether, 1-3 parts by weight of methanol, and 20-40 parts by weight of a solvent. Among them, 2,5-bis(2,4,6-tri-tert-butylanilino)-1,4-benzoquinone contains multiple tert-butyl hindered amine structures with strong free radical capture performance, which is introduced into a p-benzoquinone structure and can synergistically capture free radicals with p-benzoquinone, significantly inhibiting the polymerization of unsaturated olefins such as styrene and butadiene, and showing an excellent polymerization inhibition effect.

Description

Polymerization inhibitor for polymerization of butadiene unsaturated olefin and preparation method thereof

Technical Field

The invention relates to the technical field of polymerization inhibitors, in particular to a polymerization inhibitor for polymerizing butadiene unsaturated olefins and a preparation method thereof.

Background

Unsaturated olefins such as styrene and butadiene are an important chemical raw material and intermediate. Has wide application in the aspects of high polymer resin, plastic, rubber and the like. However, unsaturated olefin compounds such as styrene and butadiene have high activity, and when exposed to high temperature or light during storage and the like, self-polymerization reaction tends to occur, which affects the purity and chemical quality of the compounds. The polymerization inhibitor is usually added to the unsaturated olefin, and the self-polymerization reaction can be effectively suppressed.

The benzoquinone polymerization inhibitor has the advantages of various types, low cost, easy obtainment, high polymerization inhibition efficiency and the like, and has good practical application in the aspect of unsaturated olefin polymerization inhibition. The hindered amine compound has a strong effect of capturing free radicals, and has wide application prospects in the aspects of light stabilizers, polymerization inhibitors and the like. The invention aims to prepare a novel benzoquinone polymerization inhibitor containing a hindered amine structure, which is used for inhibiting the polymerization of unsaturated olefins such as styrene, butadiene and the like.

Disclosure of Invention

The invention solves the technical problems that benzoquinone polymerization inhibitor has poor polymerization inhibition effect on butadiene and the like.

The invention provides a technical scheme that the polymerization inhibitor for unsaturated olefin polymerization comprises 10-30 parts by weight of main polymerization inhibitor, 1-5 parts by weight of antioxidant, 1-5 parts by weight of diethylhydroxylamine, 20-40 parts by weight of diethylene glycol butyl ether, 1-3 parts by weight of methanol and 20-40 parts by weight of solvent.

The main polymerization inhibitor is benzoquinone, p-benzoquinone, 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone;

the structural formula of the 2- (N, N-diethylaminobenzene) amine-1, 4-benzoquinone is shown as formula (I):

formula (I).

Further, the antioxidant is p-tert-butylcatechol or 2, 5-di-tert-butylhydroquinone.

Further, the solvent is any one or combination of deionized water, acetonitrile or xylene.

Further, the preparation method of the 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone comprises the steps of adding N, N-dimethylformamide, 2, 5-diiodo-1, 4-benzoquinone, 2,4, 6-tri-tert-butyl anilino and a catalyst into a reaction bottle, adding water and ethyl acetate after reaction, standing for layering after oscillation, removing a water phase, adding anhydrous sodium sulfate into an ethyl acetate organic phase for drying, filtering, decompressing and distilling filtrate, separating by silica gel column chromatography, and carrying out gradient elution by taking a solution of petroleum ether and ethyl acetate as an eluent to obtain the 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone.

Further, the molar ratio of the 2, 5-diiodo-1, 4-benzoquinone to the 2,4, 6-tri-tert-butyl aniline to the catalyst is 1 (2-2.6) to (6-8).

Further, the catalyst is potassium fluoride or cesium fluoride.

Further, the reaction temperature is 60-90 ℃ and the reaction time is 2-8h.

Further, the preparation method of the polymerization inhibitor for unsaturated olefin polymerization comprises the steps of adding solvent, methanol, main polymerization inhibitor, antioxidant, diethyl hydroxylamine and diethylene glycol butyl ether into a reaction bottle, and stirring and mixing uniformly to obtain the polymerization inhibitor.

The invention has the technical effects that the novel 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone containing hindered amine structure is obtained by substitution reaction with 2, 5-diiodo-1, 4-benzoquinone and 2,4, 6-tri-tert-butyl anilino as reactants and potassium fluoride or cesium fluoride as catalysts.

The invention uses benzoquinone, p-benzoquinone or 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone as the main component of polymerization inhibitor, and is compounded with antioxidant 2, 5-di-tert-butyl hydroquinone, diethyl hydroxylamine, diethylene glycol butyl ether, methanol and solvent to obtain novel polymerization inhibitor for unsaturated olefin polymerization, which has good polymerization inhibiting effect on unsaturated olefin such as styrene. Wherein the 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone contains a plurality of tert-butyl hindered amine structures) The modified styrene-butadiene copolymer has strong free radical capturing performance, can be introduced into a p-benzoquinone structure to capture free radicals in a synergistic way, remarkably inhibits the polymerization of unsaturated olefins such as styrene, butadiene and the like, and shows excellent polymerization inhibition effect.

Detailed Description

The following description of the technical solutions in the embodiments of the present invention will be clear and complete, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1

2G of solvent dimethylbenzene, 0.1g of methanol, 1g of main polymerization inhibitor p-benzoquinone, 0.4g of antioxidant 2, 5-di-tert-butylhydroquinone, 0.1g of diethylhydroxylamine and 4g of diethylene glycol butyl ether are added into a reaction bottle, and the polymerization inhibitor is obtained by stirring and mixing uniformly.

Example 2

2G of solvent ionized water, 0.3g of methanol, 1g of main polymerization inhibitor benzoquinone, 0.5g of antioxidant 2, 5-di-tert-butylhydroquinone, 0.5g of diethylhydroxylamine and 3g of diethylene glycol butyl ether are added into a reaction bottle, and the polymerization inhibitor is obtained by stirring and mixing uniformly.

Example 3

6ML of N, N-dimethylformamide, 0.5mmol of 2, 5-diiodo-1, 4-benzoquinone (CAS registry number is 203579-53-7), 1.2mmol of 2,4, 6-tri-tert-butylaniline (CAS registry number is 961-38-6) and 3mmol of catalyst potassium fluoride are added into a reaction bottle, the mixture is heated to 70 ℃ for reaction for 6 hours, water and ethyl acetate are added, the mixture is oscillated and then is placed still for layering, the water phase is removed, anhydrous sodium sulfate is added into an ethyl acetate organic phase for drying, filtration and reduced pressure distillation are carried out on the filtrate, silica gel column chromatography separation is carried out, and a solution of petroleum ether and ethyl acetate is taken as an eluent for gradient elution, thus obtaining 2, 5-bis (2, 4, 6-tri-tert-butylanilino) -1, 4-benzoquinone. The reaction formula is:

;

2g of solvent acetonitrile, 0.22g of methanol, 1g of main polymerization inhibitor 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone, 0.3g of antioxidant p-tert-butyl catechol, 0.1g of diethylhydroxylamine and 2g of diethylene glycol butyl ether are added into a reaction bottle, and the polymerization inhibitor is obtained by stirring and mixing the materials uniformly.

Example 4

4ML of N, N-dimethylformamide, 0.5mmol of 2, 5-diiodo-1, 4-benzoquinone, 1mmol of 2,4, 6-tri-tert-butylaniline and 3mmol of cesium fluoride serving as a catalyst are added into a reaction bottle, heated to 90 ℃, reacted for 2 hours, added with water and ethyl acetate, and then kept still for layering after shaking, the water phase is removed, anhydrous sodium sulfate is added into an ethyl acetate organic phase for drying, filtration and reduced pressure distillation, silica gel column chromatography separation is carried out on the filtrate, and a solution of petroleum ether and ethyl acetate is used as an eluent for gradient elution to obtain 2, 5-bis (2, 4, 6-tri-tert-butylanilino) -1, 4-benzoquinone.

2G of solvent acetonitrile, 0.3g of methanol, 2g of main polymerization inhibitor 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone, 0.1g of antioxidant p-tert-butyl catechol, 0.2g of diethylhydroxylamine and 2g of diethylene glycol butyl ether are added into a reaction bottle, and the polymerization inhibitor is obtained by stirring and mixing the materials uniformly.

Example 5

6ML of N, N-dimethylformamide, 0.5mmol of 2, 5-diiodo-1, 4-benzoquinone, 1.3mmol of 2,4, 6-tri-tert-butylaniline and 4mmol of catalyst potassium fluoride are added into a reaction bottle, heated to 60 ℃, reacted for 8 hours, added with water and ethyl acetate, oscillated, kept still for delamination, the water phase is removed, anhydrous sodium sulfate is added into an ethyl acetate organic phase for drying, filtration and reduced pressure distillation of the filtrate, silica gel column chromatography separation, and gradient elution is carried out by taking a solution of petroleum ether and ethyl acetate as an eluent to obtain 2, 5-bis (2, 4, 6-tri-tert-butylanilino) -1, 4-benzoquinone.

4G of solvent acetonitrile, 0.1g of methanol, 3g of main polymerization inhibitor 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone, 0.1g of antioxidant p-tert-butyl catechol, 0.1g of diethylhydroxylamine and 4g of diethylene glycol butyl ether are added into a reaction bottle, and the polymerization inhibitor is obtained by stirring and mixing the materials uniformly.

Adding styrene and a polymerization inhibitor into a reaction bottle, controlling the dosage of the polymerization inhibitor to be 50-300 ppm percent of that of the styrene, heating to 80 ℃, reacting to 0.5 h, cooling, adding methanol to separate out precipitate, filtering, drying the precipitate, weighing, and calculating the conversion rate W of the styrene, wherein W= (m-m ₁)/(m multiplied by 100 percent), m is the mass of the styrene, and m ₁ is the mass of the precipitate. The lower the conversion, the better the polymerization inhibition effect.

TABLE 1 styrene conversion test

Adding styrene and a polymerization inhibitor into a reaction bottle, controlling the dosage of the polymerization inhibitor to be 300 ppm percent of that of the styrene, heating to 80 ℃, reacting to 0.5-2 h, cooling, adding methanol to separate out precipitate, filtering, drying the precipitate, weighing, and calculating the conversion rate W of the styrene, wherein W= (m-m ₁)/(m multiplied by 100 percent), m is the mass of the styrene, and m ₁ is the mass of the precipitate. The lower the conversion, the better the polymerization inhibition effect.

TABLE 2 styrene conversion at different reaction times

The peroxide content of butadiene was determined according to GB/T17828-1999 by introducing butadiene, oxygen, and a polymerization inhibitor into the test apparatus, the mass of oxygen being 800ppm by mass of butadiene and the mass of the polymerization inhibitor being 100ppm by mass of butadiene. Meanwhile, a rusted iron nail is added to accelerate the production of butadiene peroxide. The mixture was left at 25℃for 48 hours, and the peroxide content in butadiene was measured. The smaller the peroxide content, the better the polymerization inhibiting effect.

TABLE 3 determination of peroxide content in butadiene

It should be noted that the above-mentioned embodiments are merely preferred embodiments of the present invention, and the present invention is not limited thereto, but may be modified or substituted for some of the technical features thereof by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (9)

1. The polymerization inhibitor is characterized by comprising 10-30 parts by weight of a main polymerization inhibitor, 1-5 parts by weight of an antioxidant, 1-5 parts by weight of diethylhydroxylamine, 20-40 parts by weight of diethylene glycol butyl ether, 1-3 parts by weight of methanol and 20-40 parts by weight of a solvent;

the main polymerization inhibitor is benzoquinone, p-benzoquinone or 2, 5-di (2, 4, 6-tri-tert-butyl anilino) -1, 4-benzoquinone;

The structural formula of the 2- (N, N-diethylaminobenzene) amine-1, 4-benzoquinone is shown as the formula (I):

formula (I).

2. The polymerization inhibitor according to claim 1, wherein the antioxidant is p-tert-butylcatechol or 2, 5-di-tert-butylhydroquinone.

3. The polymerization inhibitor of claim 1, wherein the solvent is any one or a combination of deionized water, acetonitrile, or xylene.

4. The polymerization inhibitor according to claim 1, wherein the preparation method of the 2, 5-di (2, 4, 6-tri-tert-butylanilino) -1, 4-benzoquinone comprises the steps of adding N, N-dimethylformamide, 2, 5-diiodo-1, 4-benzoquinone, 2,4, 6-tri-tert-butylaniline and a catalyst into a reaction bottle, adding water and ethyl acetate after reaction, oscillating, standing for layering, removing water phase, adding anhydrous sodium sulfate into an ethyl acetate organic phase for drying, filtering, distilling the filtrate under reduced pressure, separating by silica gel column chromatography, and carrying out gradient elution by taking a solution of petroleum ether and ethyl acetate as eluent to obtain the 2, 5-di (2, 4, 6-tri-tert-butylanilino) -1, 4-benzoquinone.

5. The polymerization inhibitor according to claim 3, wherein the molar ratio of the 2, 5-diiodo-1, 4-benzoquinone, 2,4, 6-tri-t-butylaniline and the catalyst is 1 (2-2.6): 6-8.

6. The polymerization inhibitor according to claim 3, wherein the catalyst is potassium fluoride or cesium fluoride.

7. The polymerization inhibitor according to claim 3, wherein the reaction temperature is 60 to 90℃and the reaction time is 2 to 8 hours.

8. A process for preparing a polymerization inhibitor according to any one of claims 1 to 6, wherein a solvent, methanol, a main polymerization inhibitor, an antioxidant, diethylhydroxylamine and diethylene glycol butyl ether are added into a reaction vessel, and stirred and mixed uniformly to obtain the polymerization inhibitor.

9. Use of a polymerization inhibitor obtained by the preparation method according to claim 8 in the polymerization inhibition of butadiene and styrene unsaturated olefins.