CN106146696B - A cationic polymerization method - Google Patents

Abstract

The invention discloses a cationic polymerization method, which comprises the step of contacting monoolefine shown in a formula II and conjugated diolefin shown in a formula III with each component in an initiator system in alkane under the condition of solution polymerization, wherein the initiator system contains a compound capable of providing protons, Lewis acid and an activator, and the activator is selected from a compound shown in a formula I-1 and a compound shown in a formula I-2. The method is used for preparing the mono-olefin-conjugated diene copolymer and adopts simple H⁺Lewis acid initiator System comparisonThe initiation efficiency is obviously improved, and higher polymer yield can be obtained at higher polymerization rate; by adjusting the content and the type of an activating agent in an initiator system, polymers with different molecular weights can be obtained under different polymerization conditions; in addition, the method can carry out polymerization at higher temperature, and effectively reduces energy consumption in the polymerization reaction process.

Description

A cationic polymerization method

technical field

The present invention relates to a cationic polymerization method.

Background technique

At present, the slurry polymerization method using dichloromethane as diluent is widely used in the world to produce butyl rubber. The main reason is that the slurry polymerization method has high production efficiency, and the product has high molecular weight and good processability.

Compared with the slurry polymerization method, the solution polymerization method has no obvious advantages in these aspects, especially the products obtained by the solution polymerization method have low molecular weight and poor processability, so it is difficult to compete with the products obtained by the slurry polymerization method in the market . However, the development space of the solution polymerization method is relatively broad. For example, the solution polymerization method is more in line with the environmental protection requirements than the slurry polymerization method, and has a wider range of adaptation to the polymerization temperature, especially in the realization of high temperature polymerization. It has better development prospects. In addition, halogenated butyl rubber is usually prepared by solution method, that is, butyl rubber dissolved in alkane is contacted with a halogen-containing compound for halogenation reaction. When preparing butyl rubber by slurry polymerization method, it is necessary to A solvent replacement step and a polymer re-dissolution step are set between the alkane displacement slurry polymerization mixture and the halogenation reaction step, while in the solution polymerization method, if the alkane is used as the polymerization solvent, all the alkane is not required. The above solvent replacement step and the polymer redissolution step, it is obvious that the solution polymerization method is more suitable for the production of solution method halogenated butyl rubber.

However, for the production of butyl rubber in solution, the main problem is that the initiation efficiency of the initiator system is low, resulting in poor polymerization efficiency, and it is difficult to obtain high molecular weight products.

US3361725 proposes that alkyl aluminum halides are effective initiators for preparing butyl rubber in solution, and can obtain higher molecular weight products at higher temperatures, but require the molar ratio of dialkyl aluminum halides in alkyl aluminum halides It reaches more than 80%, while the molar ratio of monoalkyl aluminum dihalide is lower than 20%, thus the butyl rubber is prepared in solution (such as hexane) by the self-initiation of alkyl aluminum. However, in practice, the initiation efficiency of this initiator system is very low, and the polymerization rate is very slow, which cannot meet the needs of practical applications. For this reason, US6403747 has improved this initiator system, promptly introduces trace water or aluminoxane in above-mentioned dialkyl aluminum halide/monoalkyl aluminum dihalide mixed system, makes initiator system activity improve, thereby can The butyl rubber with a weight-average molecular weight of more than 400,000 is prepared at -60°C to -80°C. Although the initiation efficiency and polymerization rate of the initiator system disclosed in US6403747 have been improved to a certain extent, it is still unsatisfactory in the actual operation process, and the preparation of the initiator system is relatively difficult, especially the preparation technology of aluminoxane is very high. .

Therefore, for the cationic solution polymerization process of butyl rubber, it is urgent to develop a highly active initiator system suitable for solution polymerization, so as to improve the initiation efficiency and polymerization efficiency, and obtain high molecular weight products.

Contents of the invention

The object of the present invention is to provide a kind of cationic polymerization method, this method adopts solution polymerization method to prepare monoolefin-conjugated diene copolymer, can prepare monoolefin-conjugated diene copolymer with higher molecular weight with higher polymerization efficiency things.

The present invention provides a cationic polymerization process comprising contacting at least one monoolefin and at least one conjugated diene with the components of an initiator system in a polymerization solvent under solution polymerization conditions,

The initiator system contains at least one compound capable of donating protons, at least one Lewis acid and at least one activator, and the activator is selected from compounds shown in formula I-1 and compounds shown in formula I-2 ,

In formula I-1 and formula I-2, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each -H, -X ¹ , -NO ₂ , One of and -CN, X ¹ and X ² are each a kind of halogen group;

The monoolefin is selected from compounds shown in formula II,

In formula II, each of R ₉ and R ₁₀ is a C ₁ -C ₅ straight chain or branched chain alkyl group; or R ₉ is hydrogen, and R ₁₀ is a C ₃ -C ₅ branched chain alkyl group;

The conjugated diene is selected from compounds shown in formula III,

In formula III, each of R ₁₁ , R ₁₂ and R ₁₃ is hydrogen or a C ₁ -C ₅ linear or branched alkyl group;

The polymerization solvent is selected from alkanes.

Adopt the method of the present invention to prepare single olefin-conjugated diene copolymer, compared with adopting simple H ⁺ /Lewis acid initiator system, on the one hand initiation efficiency improves obviously, thereby can obtain higher with higher rate of polymerization Polymer yield; on the other hand, by adjusting the content and type of activator and Lewis acid in the initiator system, polymers with different molecular weights can be obtained under different polymerization conditions, so as to meet the requirements of different applications. In addition, compared with the simple H ⁺ /Lewis acid initiator system, the method of the present invention can carry out polymerization at a higher temperature, thereby effectively reducing energy consumption in the polymerization process.

Detailed ways

The present invention provides a cationic polymerization process comprising contacting at least one monoolefin and at least one conjugated diene with the components of an initiator system in a polymerization solvent under solution polymerization conditions.

In the present invention, "at least one kind" means one kind or two or more kinds.

According to the method of the present invention, the initiator system (which may also be referred to as initiator composition) contains at least one compound capable of donating protons, at least one Lewis acid and at least one activator.

The activator is selected from compounds shown in formula I-1 and compounds shown in formula I-2,

In formula I-1 and formula I-2, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each -H, -X ¹ , -NO ₂ , and one of -CN, each of X1 and X2 is ^one of the halogen groups ⁽ for example: -F, -Cl, -Br or -I).

Specific examples of the activator may include, but are not limited to: tetrahydro-p-benzoquinone, tetrahydro-o-benzoquinone, monofluorotrihydro-p-benzoquinone, monofluorotrihydro-o-benzoquinone, difluorodihydro-p-benzoquinone, difluorodihydro-p-benzoquinone, Fluorodihydro-o-benzoquinone, Trifluoro-hydro-p-benzoquinone, Trifluoro-o-benzoquinone, Tetrafluoro-p-benzoquinone, Tetrafluoro-o-benzoquinone, Chlorotrihydro-p-benzoquinone, Chlorotrihydro-o-benzoquinone , Dichlorodihydro-p-benzoquinone (including 2,3-dichloro-p-benzoquinone, 2,5-dichloro-p-benzoquinone, 2,6-dichloro-p-benzoquinone), dichlorodihydro-p-benzoquinone (including 3,4-dichloro-o-benzoquinone, 3,5-dichloro-o-benzoquinone, 3,6-dichloro-o-benzoquinone), trichloro-p-benzoquinone, trichloro-o-benzoquinone, tetrachloro-p-benzoquinone Benzoquinone, tetrachloro-o-benzoquinone, bromotrihydro-p-benzoquinone, bromotrihydro-o-benzoquinone, dibromodihydro-p-benzoquinone (including 2,3-dibromo-p-benzoquinone, 2,5-dibromo-p-benzoquinone p-benzoquinone, 2,6-dibromo-p-benzoquinone), dibromodihydro-o-benzoquinone (including 3,4-dibromo-o-benzoquinone, 3,5-dibromo-o-benzoquinone, 3,6-dibromo-o-benzoquinone o-benzoquinone), tribromo-hydro-p-benzoquinone, tribromo-hydro-o-benzoquinone, tetrabromo-p-benzoquinone, tetrabromo-o-benzoquinone, a fluorotrinitro-p-benzoquinone, a fluorotrinitro-o-benzoquinone , Difluorodinitro-p-benzoquinone (including 2,3-difluoro-5,6-dinitro-p-benzoquinone, 2,5-difluoro-3,6-dinitro-p-benzoquinone, 2,6 -difluoro-3,5-dinitro-p-benzoquinone), difluoro-dinitro-o-benzoquinone (including 3,4-difluoro-5,6-dinitro-o-benzoquinone, 3,5-difluoro -4,6-dinitro-o-benzoquinone, 3,6-difluoro-4,5-dinitro-o-benzoquinone), trifluoro-nitro-p-benzoquinone, trifluoro-nitro-o-benzoquinone, a Chlorotrinitro-p-benzoquinone, monochlorotrinitro-o-benzoquinone, dichlorodinitro-p-benzoquinone (including 2,3-dichloro-5,6-dinitro-p-benzoquinone, 2,5-di Chloro-3,6-dinitro-p-benzoquinone, 2,6-dichloro-3,5-dinitro-p-benzoquinone), dichlorodinitro-o-benzoquinone (including 3,4-dichloro-5 , 6-dinitro-o-benzoquinone, 3,5-dichloro-4,6-dinitro-o-benzoquinone, 3,6-dichloro-4,5-dinitro-o-benzoquinone), trichloro- Nitro-p-benzoquinone, trichloro-nitro-o-benzoquinone, bromotrinitro-p-benzoquinone, bromotrinitro-o-benzoquinone, dibromodinitro-p-benzoquinone (including 2,3-dibromo- 5,6-dinitro-p-benzoquinone, 2,5-dibromo-3,6-dinitro-p-benzoquinone, 2,6-dibromo-3,5-dinitro-p-benzoquinone), dibromo Dinitro-o-benzoquinone (including 3,4-dibromo-5,6-dinitro-o-benzoquinone, 3,5-dibromo-4,6-dinitro-o-benzoquinone, 3,6-dibromo-o-benzoquinone -4,5-dinitro-o-benzoquinone), tribromo-nitro-p-benzoquinone, tribromo-nitro-o-benzoquinone, tetranitro-p-benzoquinone, tetranitro-o-benzoquinone, fluorotricyano p-benzoquinone, one-fluorotricyano-o-benzoquinone, difluorodicyano-p-benzoquinone (including 2,3-difluoro-5,6-dicyano-p-benzoquinone, 2,5-difluoro-3, 6-dicyano-p-benzoquinone, 2,6-difluoro-3,5-dicyano-p-benzoquinone), difluorodicyano-o-benzoquinone (including 3,4-difluoro-5,6-difluoro cyano-benzoquinone, 3,5-difluoro-4,6-dicyano-benzoquinone, 3,6-difluoro-4 , 5-dicyano-o-benzoquinone), trifluoro-cyano-p-benzoquinone, trifluoro-cyano-o-benzoquinone, one chlorotricyano-p-benzoquinone, one chlorotricyano-o-benzoquinone, dichlorodi Cyano-p-benzoquinone (including 2,3-dichloro-5,6-dicyano-p-benzoquinone, 2,5-dichloro-3,6-dicyano-p-benzoquinone, 2,6-dichloro-p-benzoquinone 3,5-dicyano-p-benzoquinone), dichlorodicyano-o-benzoquinone (including 3,4-dichloro-5,6-dicyano-o-benzoquinone, 3,5-dichloro-4,6 -Dicyano-o-benzoquinone, 3,6-dichloro-4,5-dicyano-o-benzoquinone), trichloro-cyano-p-benzoquinone, trichloro-cyano-o-benzoquinone, bromotricyano p-benzoquinone, bromotricyano-o-benzoquinone, dibromodicyano-p-benzoquinone (including 2,3-dibromo-5,6-dicyano-p-benzoquinone, 2,5-dibromo-3, 6-dicyano-p-benzoquinone, 2,6-dibromo-3,5-dicyano-p-benzoquinone), dibromodicyano-o-benzoquinone (including 3,4-dibromo-5,6-di cyano-benzoquinone, 3,5-dibromo-4,6-dicyano-o-benzoquinone, 3,6-dibromo-4,5-dicyano-o-benzoquinone), tribromo-cyano-p-benzoquinone Quinone, tribromo-cyano-benzoquinone, trinitro-cyano-p-benzoquinone, trinitro-cyano-o-benzoquinone, dinitrodicyano-p-benzoquinone (including 2,3-dinitro- 5,6-dicyano-p-benzoquinone, 2,5-dinitro-3,6-dicyano-p-benzoquinone, 2,6-dinitro-3,5-dicyano-p-benzoquinone), Dinitrodicyano-o-benzoquinone (including 3,4-dinitro-5,6-dicyano-o-benzoquinone, 3,5-dinitro-4,6-dicyano-o-benzoquinone, 3 , 6-dinitro-4,5-dicyano-o-benzoquinone), a nitrotricyano-o-benzoquinone, a nitrotricyano-o-benzoquinone, tetracyano-o-benzoquinone, tetracyano-o-benzoquinone Benzoquinone, fluorotriformyl chloride p-benzoquinone, fluorotriformyl chloride o-benzoquinone, difluorodiformyl chloride p-benzoquinone (including 2,3-difluoro-5,6-diformyl chloride p-benzoquinone , 2,5-difluoro-3,6-diformyl chloride p-benzoquinone, 2,6-difluoro-3,5-diformyl chloride p-benzoquinone), difluorodiformyl chloride o-benzoquinone ( Including 3,4-difluoro-5,6-diformyl chloride o-benzoquinone, 3,5-difluoro-4,6-diformyl chloride o-benzoquinone, 3,6-difluoro-4,5- Diformyl chloride o-benzoquinone), trifluoro-formyl chloride-p-benzoquinone, trifluoro-formyl chloride o-benzoquinone, one chlorotriformyl chloride o-benzoquinone, one chlorotriformyl chloride o-benzoquinone, dichlorodi Formyl chloride p-benzoquinone (including 2,3-dichloro-5,6-diformyl chloride p-benzoquinone, 2,5-dichloro-3,6-diformyl chloride p-benzoquinone, 2,6- Dichloro-3,5-diformyl chloride-p-benzoquinone), dichloro-diformyl chloride-o-benzoquinone (including 3,4-dichloro-5,6-diformyl chloride-o-benzoquinone, 3,5- Dichloro-4,6-diformyl chloride o-benzoquinone, 3,6-dichloro-4,5-diformyl chloride o-benzoquinone), trichloro-formyl chloride-p-benzoquinone, trichloro-formyl chloride o-benzoquinone, bromotriformyl chloride-p-benzoquinone, bromotriformyl chloride-p-benzoquinone, dibromodiformyl chloride-p-benzoquinone (including 2,3-dibromoyl-5,6-diformyl chloride p-benzoquinone Benzoquinone, 2, 5-dibromo-3,6-diformyl chloride p-benzoquinone, 2,6-dibromo-3,5-diformyl chloride p-benzoquinone), dibromodiformyl chloride o-benzoquinone (including 3, 4-Dibromo-5,6-diformyl chloride o-benzoquinone, 3,5-dibromo-4,6-diformyl chloride o-benzoquinone, 3,6-dibromo-4,5-diformyl chloride benzoquinone), tribromoyl chloride-p-benzoquinone, tribromoyl chloride-o-benzoquinone, tetraformyl chloride-p-benzoquinone and tetraformyl chloride o-benzoquinone.

The activator is preferably selected from tetrahydrobenzoquinone (comprising tetrahydro-p-benzoquinone and tetrahydro-o-benzoquinone), tetrachloranil (comprising tetrahydro-p-benzoquinone and tetrahydro-o-benzoquinone), tetracyanobenzoquinone (including tetracyano-p-benzoquinone and tetracyano-o-benzoquinone) and dichlorodicyanobenzoquinone (including dichlorodicyano-p-benzoquinone and dichlorodicyano-o-benzoquinone).

The content of the activator is subject to obtaining a satisfactory polymerization effect. Generally, the molar ratio of the proton-donating compound to the activator may be 1:0.01-3, preferably 1:0.1-2.5, more preferably 1:0.2-2, and further preferably 1:0.5-2. 1.8, more preferably 1:0.8-1.5.

According to the method of the present invention, the Lewis acid and the compound capable of donating protons can be conventional choices in the field of cationic polymerization, without special limitations, as long as the Lewis acid and the compound capable of donating protons can form cationic active species and initiate polymerization That's it.

Generally, the Lewis acid can be selected from but not limited to: AlCl ₃ , BF ₃ , BCl ₃ , TiCl ₄ , SnCl ₄ , ZnCl ₂ , the Lewis acid shown in formula IV, the Lewis acid shown in formula V, and R ¹⁷ ₃ Al,

In formula IV, X ³¹ and X ³² are the same or different, and each is one of halogen groups (such as -F, -Cl, -Br or -I), preferably -Cl; R ₁₄ is C ₁ to C ₈ straight or branched chain alkyl, preferably C ₁ to C ₅ straight or branched chain alkyl, more preferably ethyl;

In formula V, X ⁴ is one of the halogen groups (such as -F, -Cl, -Br or -I), preferably -Cl; R ₁₅ and R ₁₆ are each a straight chain of C ₁ to C ₈ or The branched chain alkyl group is preferably a C ₁ -C ₅ straight chain or branched chain alkyl group, more preferably an ethyl group.

In formula V, R ₁₅ and R ₁₆ may be the same or different, and are preferably the same.

In R ¹⁷ ₃ Al, each of the three R ^17s may be a C ₁ -C ₈ straight chain or branched chain alkyl group, preferably a C ₁ -C ₅ straight chain or branched chain alkyl group. In R ¹⁷ ₃ Al, three R ¹⁷ may be the same or different, but are preferably the same.

In the present invention, C ₁ -C ₈ linear or branched chain alkyl groups include C ₁ -C ₈ straight chain alkyl groups and C ₃ -C ₈ branched chain alkyl groups. Specific examples thereof include but are not limited to: Base, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, 2-methylbutyl, 3-methylbutyl, 2,2 -Dimethylpropyl, n-hexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2,3-dimethylbutyl, 2,2-dimethylbutyl , 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2,2- Dimethylpentyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, 3,3-dimethylpentyl, 3,4-dimethylpentyl, 4,4- Dimethylpentyl, 2-ethylpentyl, 3-ethylpentyl, n-octyl, 2-methylheptyl, 3-methylheptyl, 4-methylheptyl, 5-methylheptyl Base, 6-methylheptyl, 2,2-dimethylhexyl, 2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl, 3,3-di Methylhexyl, 3,4-dimethylhexyl, 3,5-dimethylhexyl, 4,4-dimethylhexyl, 4,5-dimethylhexyl, 5,5-dimethylhexyl, 2 - ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-n-propylpentyl and 2-isopropylpentyl.

In the present invention, specific examples of the Lewis acid shown in formula IV may include but are not limited to: dichloromethylaluminum, dichloroethylaluminum, dichloro-n-propylaluminum, dichloroisopropylaluminum, dichloro-n-butyl aluminum and isobutylaluminum dichloride. Preferably, the Lewis acid represented by formula IV is ethylaluminum dichloride.

In the present invention, specific examples of the Lewis acid shown in formula V may include, but are not limited to: dimethylaluminum chloride, diethylaluminum chloride, di-n-propylaluminum chloride, diisopropylaluminum chloride, Di-n-butylaluminum chloride and diisobutylaluminum chloride. Preferably, the Lewis acid represented by formula V is diethylaluminum chloride.

In the present invention, specific examples of R ¹⁷ ₃ Al may include, but are not limited to: trimethylaluminum and triethylaluminum.

According to the method of the present invention, the Lewis acid is preferably a Lewis acid represented by formula IV and/or a Lewis acid represented by formula V, more preferably dichloroethylaluminum and/or diethylaluminum chloride.

According to the method of the present invention, in one embodiment, the Lewis acid is a Lewis acid shown in formula IV (preferably ethyl aluminum dichloride) and a Lewis acid shown in formula V (preferably diethyl chloride Aluminum), based on the total amount of Lewis acid, the content of the Lewis acid shown in formula V is 10-90 mol%, preferably 20-80 mol%, more preferably 30-70 mol%; The content of the Lewis acid is 10 to 90 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%.

The content of the Lewis acid can be a conventional amount in the field of cationic polymerization. Generally, the molar ratio of the proton-donating compound to the Lewis acid can be 0.01-1:1, preferably 0.02-0.5:1, more preferably 0.03-0.3:1, and even more preferably 0.05-0.15: 1.

The proton-donating compound may be various proton-donating compounds commonly used in the field of cationic polymerization. Generally, the compound capable of donating protons can be H ₂ O and/or protic acid, specific examples of which can include but not limited to: H ₂ O, HCl, HF, HBr, H ₂ SO ₄ , H ₂ CO ₃ , H ₃ PO ₄ and HNO ₃ . Preferably, the compound capable of donating protons is HCl.

The monoolefin and conjugated diene can be contacted with the components of the initiator system for polymerization to form a monoolefin-conjugated diene copolymer by various methods commonly used.

In one embodiment of the present invention, each component in the initiator system can be dissolved in a solvent, and the obtained mixture is aged to obtain an initiator solution; The monoolefin and the conjugated diene are mixed in a solvent.

The purpose of the aging is to make the Lewis acid in the initiator system form a stable active center for complexation initiation with the proton-donating compound and the activator, which can be carried out under conventional conditions. Generally, the aging can be carried out at a temperature ranging from -100°C to 20°C, preferably from -100°C to 0°C, more preferably from -100°C to -50°C, further preferably from -90°C to -70°C. The aging time may be 10 minutes to 10 hours. Preferably, the aging time is more than 30 minutes, such as 30 minutes to 5 hours. More preferably, the aging time is more than 60 minutes, such as 60 minutes to 120 minutes.

The solvent may be various liquid substances capable of dissolving the protonic acid, the Lewis acid and the activator. Generally, the solvent can be selected from alkanes, halogenated alkanes and aromatic hydrocarbons, preferably selected from C ₃ -C ₁₀ alkanes, C ₁ -C ₁₀ halogenated alkanes and C ₆ -C ₁₂ aromatic hydrocarbons.

As a solvent, the alkanes include aliphatic alkanes and alicyclic alkanes, such as C ₃ -C ₁₀ alkanes include C ₃ -C ₁₀ aliphatic alkanes and C ₃ -C ₁₀ alicyclic alkanes.

As a solvent, the halogenated alkanes include halogenated aliphatic alkanes and halogenated cycloaliphatic alkanes, such as C ₁ to C ₁₀ halogenated alkanes include C ₁ to C ₁₀ halogenated aliphatic alkanes and C ₃ to C ₁₀ halogenated alkanes Cycloaliphatic alkanes. The halogen atoms in the halogenated alkanes may be chlorine, bromine or fluorine, preferably chlorine or fluorine. The halogenated alkane is preferably a C ₁ -C ₄ halogenated aliphatic alkane.

Specific examples of the solvent may include, but are not limited to: propane, n-butane, isobutane, n-pentane, isopentane, neopentane, cyclopentane, n-hexane, 2-methylpentane, 3- Methylpentane, 2,3-dimethylbutane, cyclohexane, methylcyclopentane, n-heptane, 2-methylhexane, 3-methylhexane, 2-ethylpentane, 3-ethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, n-octane, 2-methylheptane, 3-methylheptane, 4-methylheptane alkane, 2,3-dimethylhexane, 2,4-dimethylhexane, 2,5-dimethylhexane, 3-ethylhexane, 2,2,3-trimethylpentane , 2,3,3-trimethylpentane, 2,4,4-trimethylpentane, 2-methyl-3-ethylpentane, n-nonane, 2-methyloctane, 3- Methyloctane, 4-methyloctane, 2,3-dimethylheptane, 2,4-dimethylheptane, 3-ethylheptane, 4-ethylheptane, 2,3, 4-trimethylhexane, 2,3,5-trimethylhexane, 2,4,5-trimethylhexane, 2,2,3-trimethylhexane, 2,2,4- Trimethylhexane, 2,2,5-trimethylhexane, 2,3,3-trimethylhexane, 2,4,4-trimethylhexane, 2-methyl-3-ethane 2-methyl-4-ethylhexane, 3-methyl-3-ethylhexane, 3-methyl-4-ethylhexane, 3,3-diethylpentane, 1-methyl-2-ethylcyclohexane, 1-methyl-3-ethylcyclohexane, 1-methyl-4-ethylcyclohexane, n-propylcyclohexane, isopropylcyclohexane Hexane, trimethylcyclohexane (including various isomers of trimethylcyclohexane, such as 1,2,3-trimethylcyclohexane, 1,2,4-trimethylcyclohexane , 1,2,5-trimethylcyclohexane, 1,3,5-trimethylcyclohexane), n-decane, 2-methylnonane, 3-methylnonane, 4-methyl Nonane, 5-methylnonane, 2,3-dimethyloctane, 2,4-dimethyloctane, 3-ethyloctane, 4-ethyloctane, 2,3,4- Trimethylheptane, 2,3,5-trimethylheptane, 2,3,6-trimethylheptane, 2,4,5-trimethylheptane, 2,4,6-trimethylheptane Heptane, 2,2,3-trimethylheptane, 2,2,4-trimethylheptane, 2,2,5-trimethylheptane, 2,2,6-trimethylheptane Alkane, 2,3,3-trimethylheptane, 2,4,4-trimethylheptane, 2-methyl-3-ethylheptane, 2-methyl-4-ethylheptane, 2-methyl-5-ethylheptane, 3-methyl-3-ethylheptane, 4-methyl-3-ethylheptane, 5-methyl-3-ethylheptane, 4- Methyl-4-ethylheptane, 4-propylheptane, 3,3-diethylhexane, 3,4-diethylhexane, 2-methyl-3,3-diethylpentane Alkane, 1,2-diethylcyclohexane, 1,3-diethylcyclohexane, 1,4-diethylcyclohexane, n-butylcyclohexane, isobutylcyclohexane, tert-butylcyclohexane, Tetramethylcyclohexane (including various isomers of tetramethylcyclohexane, such as 1,2,3,4-tetramethylcyclohexane Hexane, 1,2,4,5-tetramethylcyclohexane, 1,2,3,5-tetramethylcyclohexane), monofluoromethane, difluoromethane, trifluoromethane, carbon tetrafluoride , monochloromethane, dichloromethane, chloroform, carbon tetrachloride, monofluoroethane, difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, carbon hexafluoride, monochloro Ethane, dichloroethane, trichloroethane, tetrachloroethane, pentachloroethane, carbon hexachloride, monofluoropropane, difluoropropane, trifluoropropane, tetrafluoropropane, pentafluoropropane, hexafluoropropane Propane, Heptafluoropropane, Octafluoropropane, Monochloropropane, Dichloropropane, Trichloropropane, Tetrachloropropane, Pentachloropropane, Hexachloropropane, Heptachloropropane, Octachloropropane, Monofluorobutane, Difluorobutane, Trifluorobutane, tetrafluorobutane, pentafluorobutane, hexafluorobutane, heptafluorobutane, octafluorobutane, nonafluorobutane, decafluorobutane, monochlorobutane, dichlorobutane, Trichlorobutane, tetrachlorobutane, pentachlorobutane, hexachlorobutane, heptachlorobutane, octachlorobutane, nonachlorobutane, decachlorobutane, toluene, ethylbenzene and xylene (including ortho xylene, m-xylene, and p-xylene).

The concentration of the initiator solution can be conventionally selected and is not particularly limited. The amount of the initiator solution can be properly selected according to the specific polymerization conditions, whichever can initiate the polymerization. Those skilled in the art can determine the amount of initiator sufficient to initiate polymerization through limited experiments under the teaching of the prior art.

According to the method of the present invention, the monoolefin may be a monoolefin capable of cationic polymerization commonly used in the art. Generally, the monoolefin is selected from compounds shown in formula II,

In formula II, each of R ₉ and R ₁₀ is a C ₁ -C ₅ straight chain or branched chain alkyl group; or R ₉ is hydrogen, and R ₁₀ is a C ₃ -C ₅ branched chain alkyl group.

In the present invention, C ₁ -C ₅ linear or branched chain alkyl groups include C ₁ -C ₅ straight chain alkyl groups and C ₃ -C ₅ branched chain alkyl groups, and specific examples thereof may include but are not limited to: radical, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl and neopentyl.

Specifically, the monoolefin may be selected from but not limited to: 2-methyl-1-propene (i.e., isobutene), 2-methyl-1-butene, 3-methyl-1-butene, 2, 3-Dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2,3-dimethyl-1 -pentene, 2,4-dimethyl-1-pentene, 2-methyl-1-hexene, 2,3-dimethyl-1-hexene, 2,4-dimethyl-1- Hexene, 2,5-dimethyl-1-hexene and 2,4,4-trimethyl-1-pentene.

Preferably, the monoolefin is isobutene.

According to the method of the present invention, the conjugated diene refers to a compound containing conjugated double bonds in its molecular structure. Preferably, the conjugated dienes are selected from compounds represented by formula III,

In formula III, R ₁₁ , R ₁₂ and R ₁₃ are the same or different, and each is hydrogen or a C ₁ -C ₅ linear or branched alkyl group.

Specific examples of the conjugated diene may include, but are not limited to, butadiene and/or isoprene. More preferably, the conjugated diene is isoprene.

According to the method of the present invention, the relative amounts of the monoolefin and the conjugated diene can be properly selected according to the specific application of the final prepared polymer. Generally, based on the total amount of the monoolefin and the conjugated diene, the content of the monoolefin may be 80 to 99.5% by weight, preferably 90 to 98% by weight; the content of the conjugated diene may be It is 0.5 to 20% by weight, preferably 2 to 10% by weight.

According to the method of the present invention, the polymerization solvent is selected from alkanes. As a polymerization solvent, the alkane may be aliphatic alkane and/or alicyclic alkane, such as selected from C ₃ -C ₁₀ aliphatic alkane and C ₃ -C ₁₀ alicyclic alkane. The aliphatic alkane is preferably a C ₃ -C ₈ aliphatic alkane, more preferably a C ₅ -C ₈ aliphatic alkane. The alicyclic alkanes are preferably C ₅ -C ₁₀ alicyclic alkanes.

In the present invention, specific examples of the polymerization solvent may include, but are not limited to: propane, n-butane, isobutane, n-pentane, isopentane, neopentane, cyclopentane, n-hexane, 2-methyl Pentane, 3-methylpentane, 2,3-dimethylbutane, cyclohexane, methylcyclopentane, n-heptane, 2-methylhexane, 3-methylhexane, 2- Ethylpentane, 3-ethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, n-octane, 2-methylheptane, 3-methylheptane, 4-methylheptane, 2,3-dimethylhexane, 2,4-dimethylhexane, 2,5-dimethylhexane, 3-ethylhexane, 2,2,3- Trimethylpentane, 2,3,3-trimethylpentane, 2,4,4-trimethylpentane, 2-methyl-3-ethylpentane, n-nonane, 2-methylpentane Octane, 3-methyloctane, 4-methyloctane, 2,3-dimethylheptane, 2,4-dimethylheptane, 3-ethylheptane, 4-ethylheptane , 2,3,4-trimethylhexane, 2,3,5-trimethylhexane, 2,4,5-trimethylhexane, 2,2,3-trimethylhexane, 2 , 2,4-trimethylhexane, 2,2,5-trimethylhexane, 2,3,3-trimethylhexane, 2,4,4-trimethylhexane, 2-methane Base-3-ethylhexane, 2-methyl-4-ethylhexane, 3-methyl-3-ethylhexane, 3-methyl-4-ethylhexane, 3,3-di Ethylpentane, 1-methyl-2-ethylcyclohexane, 1-methyl-3-ethylcyclohexane, 1-methyl-4-ethylcyclohexane, n-propylcyclohexane , isopropylcyclohexane, trimethylcyclohexane, n-decane, 2-methylnonane, 3-methylnonane, 4-methylnonane, 5-methylnonane, 2,3 -Dimethyloctane, 2,4-dimethyloctane, 3-ethyloctane, 4-ethyloctane, 2,3,4-trimethylheptane, 2,3,5-trimethyloctane Methylheptane, 2,3,6-trimethylheptane, 2,4,5-trimethylheptane, 2,4,6-trimethylheptane, 2,2,3-trimethylheptane Heptane, 2,2,4-trimethylheptane, 2,2,5-trimethylheptane, 2,2,6-trimethylheptane, 2,3,3-trimethylheptane , 2,4,4-trimethylheptane, 2-methyl-3-ethylheptane, 2-methyl-4-ethylheptane, 2-methyl-5-ethylheptane, 3 -Methyl-3-ethylheptane, 4-methyl-3-ethylheptane, 5-methyl-3-ethylheptane, 4-methyl-4-ethylheptane, 4-propane Heptane, 3,3-diethylhexane, 3,4-diethylhexane, 2-methyl-3,3-diethylpentane, 1,2-diethylcyclohexane, 1,3-diethylcyclohexane, 1,4-diethylcyclohexane, n-butylcyclohexane, isobutylcyclohexane, tert-butylcyclohexane and tetramethylcyclohexane.

The polymerization solvent is preferably selected from C ₃ to C ₁₀ aliphatic alkanes, more preferably from C ₅ to C ₈ aliphatic alkanes, further preferably selected from n-pentane, isopentane, n-hexane, cyclohexane, n-heptane and isooctane.

The amount of the polymerization solvent used can be conventionally selected in the art. Generally, the polymerization solvent is used in an amount such that the total monomer concentration is 2-50% by weight, preferably 5-30% by weight, more preferably 5-20% by weight.

According to the polymerization method of the present invention, the cationic polymerization conditions can be selected conventionally in the art. Generally, the contact between monoolefin and conjugated diene and each component in the initiator system can be carried out at -120°C to 20°C, preferably -100°C to 0°C, more preferably -100°C to -40°C, more preferably -90°C to -60°C temperature range. According to the polymerization method of the present invention, the duration of the contacting can be conventionally selected in the field, generally 10-180 minutes, preferably 30-120 minutes.

According to the polymerization method of the present invention, in a preferred embodiment, the activator is tetracyanobenzoquinone (comprising tetracyano-p-benzoquinone and tetracyano-o-benzoquinone) and/or dichlorodicyanoquinone Benzoquinone (comprising dichlorodicyano-p-benzoquinone and dichlorodicyano-o-benzoquinone), the Lewis acid is the Lewis acid shown in formula IV (preferably dichloroethylaluminum) and formula V shown in Lewis acid (preferably diethyl aluminum chloride), based on the total amount of the Lewis acid, the content of the Lewis acid shown in formula IV is 30 to 70 mol%, and the content of the Lewis acid shown in formula V is 30-70 mole %, the polymerization solvent is alkane. According to this preferred embodiment, even if the polymerization is carried out at a relatively high temperature (such as not higher than -60°C to -70°C), it can be prepared with a high polymerization efficiency 10 ⁵ or more) monoolefin-conjugated diene copolymer. More preferably, the activator is dichlorodicyanobenzoquinone (including dichlorodicyano-p-benzoquinone and dichlorodicyano-o-benzoquinone), so that higher polymerization efficiency can be obtained. According to this preferred embodiment, the polymerization is carried out at a temperature of -60°C to -120°C, preferably -80°C to -90°C. In this preferred embodiment, the ratio between the components in the initiator system is not particularly limited, and may be the ratio described above, however, the molar ratio of the compound capable of donating protons to the activator is preferably 1:0.8-1.5; the molar ratio of the proton-donating compound to the Lewis acid is preferably 0.04-0.1:1. In this preferred embodiment, the rest of the reaction conditions can be the conditions described above.

According to the polymerization method of the present invention, it may further include adding a polymerization terminator to the mixture obtained after the polymerization to terminate the polymerization reaction (such as alcohol). The present invention has no particular limitation on the type and amount of the polymerization terminator, which can be a conventional choice in the field, subject to the ability to terminate the polymerization reaction, and will not be repeated here.

The present invention will be described in detail below in conjunction with the examples.

In the following examples and comparative examples, the weighing method is adopted to measure the polymer yield,

Polymer yield (%)=(weight of polymer obtained/total weight of monomers added)×100%.

In the following examples and comparative examples, the molecular weight and molecular weight distribution index of the polymer were measured by a LC-20A liquid phase gel permeation chromatograph produced by Shimadzu Corporation, using a single-aperture chromatographic column and Four-column combination. The mobile phase is tetrahydrofuran, the flow rate is 0.7mL/min; the concentration of the sample solution is 2mg/mL, and the injection volume is 200μL; the test temperature is 35°C; monodisperse polystyrene is used as the standard sample.

In the following examples and comparative examples, the AVANCE400 nuclear magnetic resonance instrument commercially available from the Swiss Bruker company is adopted, with _CDCl3 as solvent, TMS as internal standard, and the degree of unsaturation of the prepared monoolefin-conjugated diene copolymer (i.e. , the content of structural units formed from isoprene in the prepared monoolefin-conjugated diene copolymer).

The solvents and monomers used in the following examples and comparative examples were refined by methods commonly used in the art before use, and the polymerization reaction and the preparation of the initiator solution were all carried out in a nitrogen operating box equipped with a low-temperature cooling bath.

Examples 1-28 serve to illustrate the method of the present invention.

Example 1

(1) Dissolve 0.0662g of chloro-p-benzoquinone in 80g of dichloromethane solution containing HCl (concentration: 0.0036mol/L), pre-cool the resulting solution to -80°C, and then sequentially add 2.6 mL of n-hexane solution of 0.9 mol/L ethylaluminum dichloride (EADC) and 1 mL of n-heptane solution of 1.0 mol/L diethylaluminum chloride (DEAC), after mixing evenly, put The resulting mixed solution was aged at -80° C. for 80 min to obtain an initiator solution. Wherein, by weight, the content of chloro-p-benzoquinone in the initiator solution is 800ppm.

(2) Place a 250mL three-necked flask in a low-temperature cooling bath whose temperature is controlled from -80°C to -85°C, and add 85mL of n-hexane cooled to -80°C, 15mL of isobutylene cooled to -80°C and 0.5 mL of isoprene pre-cooled to -20°C was mixed uniformly to obtain a monomer solution. Add 10mL of the initiator solution prepared in step (1) to the monomer solution, mix evenly and let it stand for 30 minutes to react. During the reaction, control the cooling bath temperature to be within the range of -80°C to -85°C. After the reaction was completed, 5 mL of a methanol solution containing 0.5% by weight of NaOH was added to the reaction mixture to terminate the polymerization reaction. Then the mixed solution was placed in a hot water bath to remove the solvent, the obtained solid was washed with water, and then dried in a vacuum oven at 60° C. to constant weight to obtain a monoolefin-conjugated diene copolymer.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 2

Adopt the same method as Example 1 to carry out the polymerization, the difference is that in the step (2), during the dropwise addition of the initiator solution and the polymerization reaction, the temperature of the cold bath is controlled to be in the range of -40°C to -50°C Inside, the amount of initiator solution was 15mL, and the polymerization reaction time was 50min.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 3

Adopt the method identical with embodiment 1 to carry out polymerization, difference is, in step (1), the concentration of the n-hexane solution of EADC is 0.9mol/L, consumption is 1.9mL, the concentration of the n-heptane solution of DEAC is 1.0mol /L, the dosage is 1.7mL.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 4

Adopt the same method as Example 3 to carry out polymerization, the difference is that in step (2), during the dripping of the initiator solution and the polymerization reaction process, the temperature of the cold bath is controlled to be in the range of -60°C to -70°C Within, the polymerization reaction time is 40min.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 5

Adopt the method identical with embodiment 1 to carry out polymerization, difference is, in step (1), the concentration of the n-hexane solution of EADC is 0.9mol/L, consumption is 1.1mL, the concentration of the n-heptane solution of DEAC is 1.0mol /L, the dosage is 2.3mL. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 6

(1) 0.0602g 2,3-dichloro-5,6-dicyano-p-benzoquinone is dissolved in 80g of dichloromethane solution containing HCl (concentration is 0.0040mol/L), and the resulting solution is precooled to -85°C, and then sequentially add 2.8 mL of n-hexane solution of ethylaluminum dichloride with a concentration of 0.9 mol/L and 1.1 mL of n-heptane with a concentration of 1.0 mol/L of diethylaluminum chloride solution, after mixing evenly, place the obtained mixed solution in a cold bath at -85° C. to age for 100 minutes, thereby obtaining an initiator solution. Wherein, by weight, the content of 2,3-dichloro-5,6-dicyano-p-benzoquinone in the initiator solution is 730ppm.

(2) Place a 250mL three-necked flask in a low-temperature cooling bath whose temperature is controlled from -80°C to -85°C, and add 85mL of n-hexane cooled to -80°C, 15mL of isobutylene cooled to -80°C and 0.5 mL of isoprene pre-cooled to -20°C was mixed uniformly to obtain a monomer solution. Add 10mL of the initiator solution prepared in step (1) to the monomer solution, mix well and let it stand for 30 minutes to react, add the initiator solution dropwise and control the temperature of the cooling bath in the range of -80°C to -85°C during the reaction Inside. After the reaction was completed, 5 mL of a methanol solution containing 0.5% by weight of NaOH was added to the reaction mixture to terminate the polymerization reaction. Then the mixed solution was placed in a hot water bath to remove the solvent, the obtained solid was washed with water, and then dried in a vacuum oven at 60° C. to constant weight to obtain a monoolefin-conjugated diene copolymer. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Comparative example 1

The initiator solution was prepared and polymerized in the same manner as in Example 6, except that 2,3-dichloro-5,6-dicyano-p-benzoquinone was not used in step (1).

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 7

The initiator solution was prepared and polymerized in the same manner as in Example 6, except that in step (1), diethylaluminum chloride was replaced with an equimolar amount of ethylaluminum dichloride.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 8

Adopt the same method as Example 6 to carry out polymerization, the difference is that in step (2), during the dropwise addition of the initiator solution and the polymerization reaction, the temperature of the cold bath is controlled to be in the range of -60°C to -70°C , the amount of initiator solution was 15mL, and the polymerization reaction time was 40min.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 9

Adopt the same method as Example 6 to carry out polymerization, the difference is that in step (1), the concentration of the n-hexane solution of ethyl aluminum dichloride is 0.9mol/L, and the consumption is 2mL; The concentration of the heptane solution is 1.0mol/L, and the dosage is 1.8mL.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 10

Adopt the same method as Example 9 to carry out polymerization, the difference is that in step (2), during the dropwise addition of the initiator solution and the polymerization reaction, the temperature of the cold bath is controlled to be in the range of -60°C to -70°C Within, the polymerization reaction time is 40min.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 11

Adopt the same method as Example 9 to carry out polymerization, the difference is that in step (2), during the dropwise addition of the initiator solution and the polymerization reaction, the temperature of the cold bath is controlled to be in the range of -40°C to -50°C Within, the polymerization reaction time is 50min. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 12

Adopt the method identical with embodiment 6 to carry out polymerization, difference is, in step (1), the concentration of the n-hexane solution of ethyl aluminum dichloride is 0.9mol/L, and consumption is 1.2mL; The concentration of n-heptane solution is 1.0mol/L, and the dosage is 2.5mL.

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 13

Polymerization was carried out in the same manner as in Example 6, except that in step (1), the aging time was 60 min. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 14

Polymerization was carried out in the same manner as in Example 6, except that in step (1), the aging time was 30 min. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 15

Polymerization was carried out in the same manner as in Example 6, except that in step (1), the aging time was 10 min. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 16

Polymerization was carried out in the same manner as in Example 6, except that in step (1), 2,3-dichloro-5,6-dicyano was replaced by an equal weight of tetrahydro-p-benzoquinone. The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 17

Adopt the same method as Example 6 to carry out polymerization, the difference is that in step (1), 2,3-dichloro-5,6-dicyano is replaced by tetracyano-p-benzoquinone of equal weight .

The weight of the obtained polymer was measured, the polymer yield was calculated, and the molecular weight, molecular weight distribution index and degree of unsaturation of the polymer were measured, and the results are listed in Table 1.

Example 18

(1) Dissolve 0.0632g of chloro-p-benzoquinone in 80g of dichloromethane solution containing HCl (concentration: 0.0038mol/L), then pre-cool the above solution to -85°C, add pre-cooled to -85°C 4 mL of n-hexane solution containing ethylaluminum dichloride (concentration: 0.9 mol/L), mixed evenly, and aged at -85°C for 100 min to obtain an initiator solution. By weight, in the initiator solution that obtains, the concentration of tetrachloro-p-benzoquinone is 760ppm.

(2) Place a 250mL two-necked glass reaction bottle in a low-temperature cold bath whose temperature is controlled from -80°C to -85°C, and add 85mL of n-hexane pre-cooled to -80°C and 15mL of n-hexane pre-cooled to -85°C into the glass reaction bottle. 80°C isobutylene, 0.5mL isoprene pre-cooled to -20°C, after mixing evenly, add 15mL of the initiator solution prepared in step (1) dropwise, and then let it stand for reaction for 30min. During the dropwise addition and reaction, control The cooling bath temperature was in the range of -80°C to -85°C. After the reaction was completed, 5 mL of a methanol solution containing 0.5% by weight of NaOH was added to the reaction mixture to terminate the polymerization reaction. The obtained mixed solution was placed in a hot water bath to remove the solvent, and the obtained solid was washed with water and then dried in a vacuum oven at 60° C. to constant weight to obtain a monoolefin-conjugated diene copolymer.

The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 19

Polymerization was carried out in the same manner as in Example 18, except that during the dropwise addition of the initiator solution and the polymerization reaction, the temperature was controlled to be within the range of -60°C to -70°C, and the polymerization reaction time was 40min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 20

Polymerization was carried out in the same manner as in Example 18, except that during the dropwise addition of the initiator solution and the polymerization reaction, the temperature was controlled within the range of -40°C to -50°C, and the polymerization reaction time was 50min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 21

(1) Dissolve 0.0484g of chloro-p-benzoquinone in 60g of dichloromethane solution containing HCl (concentration: 0.0044mol/L), then pre-cool the above solution to -85°C, add 3mL to pre-cool to -85 °C and n-hexane containing ethylaluminum dichloride (concentration: 0.9 mol/L), mixed uniformly, and aged at -85 °C for 70 min to obtain an initiator solution. Wherein, by weight, in the initiator solution, the concentration of chloranil is 780ppm.

(2) Add 200 mL of n-hexane pre-cooled to -85 °C, 40 mL of isobutylene pre-cooled to -85 °C and 1 mL of isoprene pre-cooled to -20 °C in a 500 mL glass reactor equipped with strong constant speed stirring After mixing evenly, add 30mL of the initiator solution prepared in step (1) dropwise, and then react for 20min. During the dropwise addition and reaction, the temperature is controlled within the range of -80°C to -85°C. After the reaction was completed, 10 mL of a methanol solution containing 0.5% by weight of NaOH was added to the reaction mixture to terminate the polymerization reaction. The obtained mixed solution was placed in a hot water bath to remove the solvent, and the obtained solid was washed with water and then dried in a vacuum oven at 60° C. to constant weight to obtain a monoolefin-conjugated diene copolymer.

The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 22

Polymerization was carried out in the same manner as in Example 21, except that an equal weight of tetracyano-p-benzoquinone was used instead of tetrachloro-p-benzoquinone. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Comparative example 2

Polymerization was carried out in the same manner as in Example 21, except that the initiator solution prepared in step (1) did not contain tetrachloro-p-benzoquinone. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 23

(1) 0.0634g 2,3-dichloro-5,6-dicyano-p-benzoquinone is dissolved in 84.6g and contains HCl (concentration is 0.0041mol/L) in the dichloromethane solution, then above-mentioned solution is pre- Cool to -85°C, add 4 mL of n-hexane solution containing ethylaluminum dichloride (concentration: 0.9mol/L) pre-cooled to -85°C, mix well, and age at -85°C for 100min to obtain the initiator solution. Wherein, by weight, in the initiator solution, the concentration of 2,3-dichloro-5,6-dicyano-p-benzoquinone is 730ppm.

(2) Place a 250mL two-necked glass reaction bottle in a low-temperature cold bath whose temperature is controlled from -80°C to -85°C, and add 85mL of n-hexane pre-cooled to -80°C and 15mL of n-hexane pre-cooled to -85°C into the glass reaction bottle. 80°C isobutylene, 0.5mL isoprene pre-cooled to -20°C, after mixing evenly, add 10mL of the initiator solution prepared in step (1) dropwise, and then let it stand for reaction for 30min. During the dropwise addition and reaction, control The cooling bath temperature was in the range of -80°C to -85°C. After the reaction was completed, 5 mL of a methanol solution containing 0.5% by weight of NaOH was added to the reaction mixture to terminate the polymerization reaction. The obtained mixed solution was placed in a hot water bath to remove the solvent, and the obtained solid was washed with water and then dried in a vacuum oven at 60° C. to constant weight to obtain a monoolefin-conjugated diene copolymer. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 24

Use the same method as Example 23 to carry out the polymerization, the difference is that in step (2), the amount of the initiator solution added is 15mL, and the initiator solution is added dropwise within the temperature range of -60°C to -70°C and carried out Reaction, polymerization reaction time is 40min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 25

The same method as in Example 23 is used for polymerization, except that in step (2), the amount of the initiator solution added is 15mL, and the initiator solution is added dropwise in the temperature range of -40°C to -50°C and carried out Reaction, polymerization reaction time is 50min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 26

Polymerization was carried out in the same manner as in Example 23, except that in step (1), the aging time was 60 min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 27

Polymerization was carried out in the same manner as in Example 23, except that in step (1), the aging time was 30 min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

Example 28

Polymerization was carried out in the same manner as in Example 23, except that in step (1), the aging time was 10 min. The polymer yields, unsaturation, molecular weight and molecular weight distribution index of the resulting polymers are listed in Table 2.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention. These simple modifications All belong to the protection scope of the present invention.

In addition, it should be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way if there is no contradiction. The combination method will not be described separately.

In addition, various combinations of different embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the idea of the present invention, they should also be regarded as the disclosed content of the present invention.

Claims (28)

1. A cationic polymerization process comprising contacting at least one monoolefin and at least one conjugated diene with the components of the initiator system in a polymerization solvent under solution polymerization conditions, The initiator system is composed of at least one proton-donating compound, at least one Lewis acid and at least one activator, and the molar ratio of the proton-donating compound to the activator is 1:0.01-3, The molar ratio of the proton-donating compound to the Lewis acid is 0.01-1:1, and the activator is selected from the compound shown in formula I-1 and the compound shown in formula I-2, In formula I-1 and formula I-2, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each -H, -X ¹ , -NO ₂ , One of and -CN, X ¹ and X ² are each a kind of halogen group; The Lewis acid is a Lewis acid shown in formula IV and/or a Lewis acid shown in formula V, In formula IV, each of X ³¹ and X ³² is one of the halogen groups; R ₁₄ is a C ₁ -C ₈ linear or branched alkyl group; In formula V, X ⁴ is one of the halogen groups; R ₁₅ and R ₁₆ are each straight-chain or branched-chain alkyl of C ₁ to C ₈ ; The monoolefin is selected from compounds shown in formula II, In formula II, each of R ₉ and R ₁₀ is a C ₁ -C ₅ straight chain or branched chain alkyl group; or R ₉ is hydrogen, and R ₁₀ is a C ₃ -C ₅ branched chain alkyl group; The conjugated diene is selected from compounds shown in formula III, In formula III, each of R ₁₁ , R ₁₂ and R ₁₃ is hydrogen or a C ₁ -C ₅ linear or branched alkyl group; The polymerization solvent is selected from alkanes. 2. The method according to claim 1, wherein the molar ratio of the proton-donating compound to the activator is 1:0.1-2.5. 3. The method according to claim 2, wherein the molar ratio of the proton-donating compound to the activator is 1:0.2-2. 4. The method according to claim 3, wherein the molar ratio of the proton-donating compound to the activator is 1:0.5-1.8. 5. The method according to claim 1, wherein the molar ratio of the proton-donating compound to the Lewis acid is 0.02-0.5:1. 6. The method according to claim 5, wherein the molar ratio of the proton-donating compound to the Lewis acid is 0.03-0.3:1. 7. The method according to claim 6, wherein the molar ratio of the proton-donating compound to the Lewis acid is 0.05-0.15:1. 8. The method according to any one of claims 1-7, wherein the activator is selected from the group consisting of tetrahydrobenzoquinone, tetrachlorobenzoquinone, tetracyanobenzoquinone and dichlorodicyanobenzoquinone. 9. The method according to any one of claims 1 to 7, wherein, in formula IV, X ³¹ and X ³² are each -Cl; R ₁₄ is ethyl; In formula V, X ⁴ is -Cl; R ₁₅ and R ₁₆ are each ethyl. 10. The method according to any one of claims 1-7, wherein the Lewis acid is ethylaluminum dichloride and/or diethylaluminum chloride. 11. The method according to any one of claims 1-7, wherein the compound capable of donating a proton is H ₂ O and/or a protic acid. 12. The method of claim 11, wherein the compound capable of donating a proton is HCl. 13. The method of claim 1, wherein the contacting is performed at a temperature ranging from -120°C to 20°C. 14. The method of claim 13, wherein the contacting is performed at a temperature ranging from -100°C to 0°C. 15. The method of claim 14, wherein the contacting is performed at a temperature ranging from -100°C to -40°C. 16. The method of claim 15, wherein the contacting is performed at a temperature ranging from -90°C to -60°C. 17. The process according to any one of claims 1 to 7 and 13 to 16, wherein the contacting of at least one monoolefin and at least one conjugated diene with the components in the initiator system The method comprises: dissolving each component in the initiator system in a solvent, and aging the obtained mixture to obtain an initiator solution; combining the initiator solution with the monoolefin dissolved in the polymerization solvent and The conjugated dienes are mixed. 18. The method according to claim 17, wherein the aging time is 10 minutes to 10 hours. 19. The method according to claim 18, wherein the aging time is 30 minutes to 5 hours. 20. The method according to claim 19, wherein the aging time is 60 minutes to 120 minutes. 21. The method of claim 17, wherein the aging is performed at a temperature ranging from -100°C to 20°C. 22. The method of claim 21, wherein the aging is performed at a temperature ranging from -100°C to 0°C. 23. The method of claim 22, wherein the aging is performed at a temperature ranging from -100°C to -50°C. 24. The method of claim 23, wherein the aging is performed at a temperature ranging from -90°C to -70°C. 25. The method according to claim 1, wherein, based on the total amount of the monoolefin and the conjugated diene, the content of the monoolefin is 80 to 99.5% by weight; the conjugated diene The content is 0.5 to 20% by weight. 26. The method according to claim 25, wherein, based on the total amount of the monoolefin and the conjugated diene, the content of the monoolefin is 90 to 98% by weight; the conjugated diene The content is 2 to 10% by weight. 27. The method according to any one of claims 1-7, 13-16, 25 and 26, wherein the conjugated diene is isoprene; and/or The monoolefin is isobutylene. 28. The method according to claim 1, wherein the polymerization solvent is one or two or more selected from C ₃ -C ₁₀ aliphatic alkanes.