Ethylene / (methyl) acrylate copolymer as well as preparation method and application thereof

Abstract

The invention belongs to the field of olefin polymerization, and relates to an ethylene / (methyl) acrylate copolymer as well as a preparation method and application thereof. The copolymer comprises 85-95 mol% of a structural unit derived from ethylene and 5-15 mol% of a structural unit derived from (methyl) acrylate; the number average molecular weight of the copolymer ranges from 2000 g / mol to 5500 g / mol; and the (meth) acrylate is inserted into the main chain of the copolymer in a proportion of 70 mol% or more. The ethylene / (methyl) acrylate copolymer disclosed by the invention has relatively high comonomer content, meanwhile, the proportion of comonomers inserted into a main chain is relatively high, and the ethylene / (methyl) acrylate copolymer has good solubility in hydrocarbon solvents and even aliphatic hydrocarbons and can be used as a quenching agent in olefin solution polymerization; and the enough molecular weight enables the quenching agent to basically not enter the solvent and unreacted monomers in the separation process, and a purification system does not need to be independently arranged in a recovery system, so that the investment cost and the operation cost of the device are saved.

Description

Technical Field

[0001] The present invention belongs to the field of olefin polymerization. Specifically, it relates to an ethylene / (meth)acrylate copolymer, a preparation method of the ethylene / (meth)acrylate copolymer, and an application of the ethylene / (meth)acrylate copolymer in olefin solution polymerization. Background Art

[0002] When producing polyolefins by solution polymerization process, a quenching agent is usually required to prevent further polymerization of unreacted monomers downstream of the reactor. After polymerization, the solvent and / or unreacted monomers are usually removed from the final product through separation and / or recovery steps. The solvent and / or monomers can then be recycled back to the polymerization process. Small molecule polar compounds, such as water or methanol, are usually used as quenching agents. However, such small molecule quenching agents will be present in the solvent and unreacted monomers during the separation and recovery process. Usually, a purification device needs to be added to avoid the small molecule quenching agent being recycled into the reaction system to poison the catalyst. The purification device needs to be regenerated frequently, and the scavengers used are also expensive. At the same time, it will increase the complexity of the process and the operating cost.

[0003] Macromolecular quenching agents are not easily incorporated into the solvent and unreacted monomers during the separation process, which will well solve the above problems. However, if the molecular weight of the macromolecular quenching agent is too large or the structure is inappropriate, it may be insoluble in the polyolefin solution downstream of the reactor, thus affecting the catalyst inactivation effect.

[0004] Therefore, there is a need in the art to develop an improved quenching agent with a suitable molecular weight, chain structure, and solubility in hydrocarbon solvents. Summary of the Invention

[0005] The object of the present invention is to provide a functionalized ethylene copolymer quenching agent, a preparation method of the copolymer, and an application of the copolymer in olefin solution polymerization.

[0006] The first aspect of the present invention provides an ethylene / (meth)acrylate copolymer, the copolymer comprising 85 - 95 mol% of structural units derived from ethylene and 5 - 15 mol% of structural units derived from (meth)acrylate; the number average molecular weight of the copolymer is between 2000 - 5500 g / mol; the proportion of (meth)acrylate inserted into the main chain of the copolymer is above 70 mol%.

[0007] The second aspect of the present invention provides a preparation method of the above ethylene / (meth)acrylate copolymer, the method comprising: copolymerizing ethylene and (meth)acrylate monomers present in an inert solvent in the presence of a catalyst system, and then separating the resulting copolymer from the solvent;

[0008] wherein, the catalyst system comprises:

[0009] (i) Component a, the main catalyst, is at least one selected from the compounds represented by formula (I);

[0010]

[0011] In formula (I), R 1 and R 2 and R 3 are the same or different and are each independently a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group. These groups are linear, branched or cyclic and are optionally further substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group, and L is a ligand;

[0012] (ii) Component b is at least one selected from the compounds represented by formula (II) and the compounds represented by formula (III):

[0013]

[0014] In formula (II), R 4 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group. These groups are linear, branched or cyclic and are optionally further substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 1 -C 6 carbonyl group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group;

[0015] In formula (III), R 5 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C20 A hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group, these groups being linear, branched or cyclic and optionally substituted by a halogen atom, C 1 -C 10 alkyl group, C 1 -C 10 alkoxy group, C 1 -C 6 carbonyl group, C 6 -C 10 aryl group or C 6 -C 10 aryloxy group is further substituted.

[0016] The third aspect of the present invention provides the use of the ethylene / (meth)acrylate copolymer in the solution polymerization of olefins.

[0017] The fourth aspect of the present invention provides a method for the solution polymerization of olefins, comprising the following steps: polymerizing a polymerization monomer in the presence of a solvent, a catalyst and the above-mentioned ethylene / (meth)acrylate copolymer.

[0018] The ethylene / (meth)acrylate copolymer of the present invention has a high comonomer content, and at the same time, the proportion of comonomer inserted into the main chain is high. It has good solubility in hydrocarbon solvents, even in aliphatic hydrocarbons, and can be used as a quenching agent in the solution polymerization of olefins. And the sufficient molecular weight enables the quenching agent to basically not enter the solvent and unreacted monomers during the separation process, so that a separate purification system does not need to be set up in the recovery system, saving the investment cost and operation cost of the device.

[0019] Other features and advantages of the present invention will be described in detail in the following specific embodiments section. Specific Embodiments

[0020] The following details the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only for illustrating and explaining the present invention and are not used to limit the present invention.

[0021] The present invention provides an ethylene / (meth)acrylate copolymer, which copolymer comprises 85 to 95 mol% of structural units derived from ethylene and 5 to 15 mol% of structural units derived from (meth)acrylate. Preferably, the copolymer comprises 88 to 94 mol% of structural units derived from ethylene and 6 to 12 mol% of structural units derived from (meth)acrylate; the number-average molecular weight of the copolymer is between 2000 and 5500 g / mol, preferably between 2500 and 3500 g / mol; the proportion of (meth)acrylate inserted into the main chain of the copolymer is more than 70 mol%.

[0022] According to the present invention, the term "proportion of (meth)acrylate inserted into the main chain of the copolymer" refers to the ratio of the molar amount of the structural units derived from (meth)acrylate on the polymer main chain to the total molar amount of the structural units derived from (meth)acrylate in the copolymer, which is preferably more than 80 mol%, more preferably more than 85 mol%, and even more preferably more than 90 mol%.

[0023] The copolymer of the present invention has good hydrocarbon solubility. Specifically, the solubility of the copolymer in a hydrocarbon solvent at 60 °C is greater than 0.35 wt%. The hydrocarbon solvent includes both aromatic hydrocarbons and aliphatic hydrocarbons. Further, the solubility of the copolymer in an aromatic hydrocarbon solvent at 60 °C is greater than 0.8 wt%, preferably greater than 1.5 wt%, more preferably greater than 5 wt%, and even more preferably greater than 10 wt%. The copolymer of the present invention also has good solubility in an aliphatic hydrocarbon solvent. Specifically, the solubility of the copolymer in an aliphatic hydrocarbon solvent at 60 °C is greater than 0.35 wt%, preferably greater than 0.5 wt%, more preferably greater than 0.6 wt%, and even more preferably greater than 0.8 wt%.

[0024] According to the present invention, the (meth)acrylate may be at least one of the compounds represented by formula (A).

[0025]

[0026] In formula (A), R a is a hydrogen atom or a methyl group, and R b is a linear or branched C 1 -C 10 alkyl group, preferably a linear or branched C 1 -C 8 alkyl group; wherein C 1 -C 8The alkyl group can be linear or branched, including but not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-ethylhexyl. Specifically, the (meth)acrylate is preferably at least one of methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate and 2-ethylhexyl methacrylate.

[0027] The present invention also provides a method for preparing the above ethylene / (meth)acrylate copolymer, which method comprises: copolymerizing ethylene present in an inert solvent with (meth)acrylate in the presence of a catalyst system, and then separating the resulting copolymer from the solvent;

[0028] Wherein, the catalyst system comprises:

[0029] (i) Component a, a main catalyst, selected from at least one of the compounds represented by formula (I);

[0030]

[0031] In formula (I), R 1 , R 2 , R 3 are the same or different and are each independently a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group. These groups are linear, branched or cyclic and are optionally further substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group. L is a ligand; preferably, in formula (I), R 1 , R 2 , R 3 are the same or different and are each independently a hydrogen atom, a substituted or unsubstituted C 1 -C 10 hydrocarbyl group, a substituted or unsubstituted C 1 -C 10 alkoxy group or a substituted or unsubstituted C 6 -C 10Aryloxy groups, these groups being linear, branched or cyclic and optionally substituted by a halogen atom, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 6 -C 8 aryl or C 6 -C 8 aryloxy further substituted, L being Me 2 SO; more preferably, R 1 、R 2 、R 3 are the same or different and each independently is a hydrogen atom, a substituted or unsubstituted C 1 -C 6 alkyl, a substituted or unsubstituted C 1 -C 6 alkoxy or a substituted or unsubstituted C 6 -C 8 aryloxy, these groups being linear, branched or cyclic and optionally substituted by a halogen atom, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 6 -C 8 aryl or C 6 -C 8 aryloxy further substituted;

[0032] (ii) Component b, selected from at least one of the compounds represented by formula (II) and the compounds represented by formula (III):

[0033]

[0034] In formula (II), R 4 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl, a substituted or unsubstituted C 1 -C 20 alkoxy or a substituted or unsubstituted C 6 -C 20 aryloxy, these groups being linear, branched or cyclic and optionally substituted by a halogen atom, C 1 -C 10 alkyl, C 1 -C 10 alkoxy, C 1 -C 6 carbonyl, C 6 -C 10 aryl or C 6 -C 10The aryloxy group is further substituted; preferably, in formula (II), R 4 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 10 alkyl group, a substituted or unsubstituted C 8 -C 16 conjugated cycloalkyl group, a substituted or unsubstituted C 1 -C 10 alkoxy group or a substituted or unsubstituted C 6 -C 10 aryloxy group. These groups are linear, branched or cyclic and are optionally substituted by a halogen atom, a C 1 -C 6 alkyl group, a C 1 -C 6 alkoxy group, a C 1 -C 3 carbonyl group, a C 6 -C 8 aryl group or a C 6 -C 8 aryloxy group is further substituted;

[0035] In formula (III), R 5 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbon group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group. These groups are linear, branched or cyclic and are optionally substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group is further substituted; preferably, in formula (III), R 5 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 10 alkyl group, a substituted or unsubstituted C 8 -C 16 conjugated cycloalkyl group, a substituted or unsubstituted C 1 -C 10 alkoxy group or a substituted or unsubstituted C 6 -C 10 aryloxy group. These groups are linear, branched or cyclic and are optionally substituted by a halogen atom, a C 1 -C 6 alkyl group, a C 1 -C 6Alkoxy, C 1 -C 3 Carbonyl, C 6 -C 8 Aryl or C 6 -C 8 Is further substituted with aryloxy.

[0036] According to some specific embodiments of the present invention, the component a is at least one of palladium 2-(bis(2-methoxyphenyl)phosphino)benzenesulfonate, palladium 2-(bis(2-phenoxyphenyl)phosphino)benzenesulfonate, and palladium 2-(bis(2-methoxyphenyl)phosphino)-4-methylbenzenesulfonate.

[0037] According to some specific embodiments of the present invention, the component b is at least one of 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butylphenol, 2,4,6-tri-tert-butylphenol, and 2,6-di-tert-butyl-α-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadienylidene)-p-tolyloxy radical (galvinoxyl radical).

[0038] The catalyst system used in the present invention only requires a main catalyst and component b, and may not require conventional cocatalysts (such as alkylaluminums, alkylaluminoxanes, organoboron compounds, etc.) in the field of olefin polymerization.

[0039] The inert solvent used in the preparation method of the present invention can be various inert solvents commonly used in the field of olefin polymerization, including aliphatic hydrocarbon solvents and / or aromatic hydrocarbon solvents; preferably, the inert solvent is C 6 -C 12 alkane and / or C 6 -C 10 monocyclic aromatic hydrocarbon; wherein the C 6 -C 12 alkane is preferably at least one of n-hexane, iso-hexane, n-heptane, iso-heptane, n-octane, iso-octane, and cyclohexane; the C 6 -C 10 monocyclic aromatic hydrocarbon is preferably toluene and / or xylene; more preferably, the inert solvent is at least one of n-hexane, iso-hexane, cyclohexane, and toluene, and most preferably toluene.

[0040] According to the present invention, the addition of component b can improve the polymerization reaction activity. The inventors found in the research that premixing the (meth)acrylate with component b in the catalyst system to obtain a premix, and then mixing it with other components of the polymerization reaction system can further improve the reaction activity. Specifically, the premixing time is preferably 1 to 30 minutes, more preferably 2 to 15 minutes, and further preferably 3 to 10 minutes.

[0041] The preparation method of the present invention can improve the insertion rate of the comonomer in the main chain. Therefore, without a too high comonomer addition amount, the copolymer can have a high comonomer content. Specifically, in the polymerization reaction system, the concentration of the (meth)acrylate can be 5 mol / L or less, preferably 2 mol / L or less, more preferably 1 mol / L or less.

[0042] According to the present invention, preferably, the molar ratio of the (meth)acrylate to the component b in the catalyst system is 50:1 to 500:1, preferably 100:1 to 350:1, more preferably 150:1 to 300:1.

[0043] According to the present invention, preferably, in the catalyst system, the molar ratio of the main catalyst based on Pd atoms to the component b is 1:1 to 1:200, preferably 1:3 to 1:100, more preferably 1:4 to 1:50, and further preferably 1:5 to 1:30.

[0044] The copolymerization of the present invention can be carried out in a continuous or semi - continuous operation, or in a batch operation.

[0045] The copolymerization can adopt mild process conditions. Specifically, the temperature of the copolymerization can be 20 - 150 °C, preferably 40 - 120 °C, more preferably 60 - 100 °C; the pressure of the copolymerization can be 10 MPa or less, preferably 0.01 - 5 MPa, more preferably 0.1 - 2 MPa.

[0046] For ethylene / (meth)acrylate copolymers, to obtain a high comonomer content, a high - pressure free - radical reaction is usually required. The present invention adopts the coordination polymerization as described above, and a high comonomer content can be achieved at a lower pressure.

[0047] The separation of the obtained copolymer from the solvent can adopt various separation methods commonly used in the field of olefin polymerization, such as evaporation. This step can usually also remove the unreacted monomers at the same time.

[0048] The preparation method of the copolymerization further includes drying the copolymer after separating and removing the solvent and unreacted monomers.

[0049] The ethylene / (meth)acrylate copolymer of the present invention can be applied to olefin solution polymerization. Specifically, it can be used as a quenching agent.

[0050] Furthermore, the present invention provides an olefin solution polymerization method, including the following steps: in the presence of a solvent, a catalyst, and the above - mentioned ethylene / (meth)acrylate copolymer, polymerize the polymerization monomers.

[0051] Preferably, based on the molar amount of the comonomer in the copolymer per mole of the catalyst, the addition amount of the copolymer is at most 100 mol, preferably at most 50 mol, and more preferably at most 30 mol.

[0052] The present invention will be further described below in conjunction with examples, but the scope of the present invention is not limited to these examples.

[0053] The content of the comonomer in the product was determined by the following method: Nuclear magnetic resonance hydrogen spectrum measurement was carried out at room temperature using deuterated chloroform as a solvent. Taking the chemical shifts of 3.59 ppm and 3.66 ppm as the signals of the MA unit on the polymer chain and the MA unit at the chain end respectively, the MA content in the product and the proportion of MA inserted into the copolymer main chain were calculated by comparing the peak areas.

[0054] The number-average molecular weight was determined by the following method: High-temperature GPC was used for measurement. The PL-GPC 220 type gel permeation chromatography of Polymer Laboratory company was adopted. The sample was dissolved in 1,2,4-trichlorobenzene with a concentration of 1.0 mg / ml. The test temperature was 150 °C and the solution flow rate was 1.0 ml / min. The molecular weight of polystyrene was used as an internal reference to establish a standard curve, and the molecular weight of the sample was calculated according to the elution time.

[0055] The method for determining and calculating the proportion of (meth)acrylate inserted into the copolymer main chain is as follows: Nuclear magnetic resonance hydrogen spectrum measurement was carried out at room temperature using deuterated chloroform as a solvent. Taking the chemical shifts of 3.59 ppm and 1.25 ppm as the signals of the MA unit on the polymer chain and the polyethylene unit respectively, the proportion of (meth)acrylate inserted into the copolymer main chain was calculated by comparing the peak areas.

[0056] The catalyst PSPd-1 used was prepared by the following method:

[0057]

[0058] An 2 Preparation of P(OMe)

[0059] An 2 PNEt 2 (103 g, 325 mmol) in methanol (200 mL) was heated to 65 °C and stirred for 4 hours. After cooling to room temperature, the solution was concentrated in vacuo to obtain a white solid An 2 P(OMe) (88.5 g, yield 99%). 1 H NMR(CD 2 Cl 2 ): δ = 3.68(d, 3H, POCH 3), 3.82 (s, 6H, 2OCH3), 6.9 - 7.4 (m, 8H, arom); 31 P NMR (CD 2 Cl 2 ): δ = 101.7 ppm.

[0060] Preparation of phosphonic acid ligand 1a

[0061] At 0 °C, n-hexyllithium (25 ml, 62 mmol, 2.5 M hexane solution) was added dropwise to a solution of benzenesulfonic acid (5.2 g, 32.9 mmol) in 60 mL of tetrahydrofuran. After warming to room temperature and stirring for 20 h, a solution of bis[2-((oxo)diphenylphosphino)phenyl] ether (9.1 g, 32.9 mmol) in 20 mL of tetrahydrofuran was added dropwise to the solution and stirring was continued for 16 h. Then ammonium chloride (3.4 g, 62 mmol) was added thereto, and the mixture was concentrated under reduced pressure and 100 mL of water was added to the crude product. This mixture was washed twice with 80 mL of methyl tert-butyl ether and acidified to pH = 2 with concentrated hydrochloric acid. The aqueous phase was extracted twice with 120 mL of dichloromethane, the combined organic phases were dried over anhydrous magnesium sulfate, filtered, and the filtrate was cooled to -35 °C until white crystals precipitated. The solid was collected and dried to obtain phosphonic acid ligand 1a (3.72 g, yield 28%). 1 1H NMR (C 2 D 2 Cl 4 , 400 MHz, -25 °C) δ = 9.25 (d, 1 JPH = 607 Hz, PH), 6.7 - 8.2 (m, 12H, arom), 3.79 (s, 6H, 2OCH 3 ).

[0062] PdCl 2 Preparation of PdCl(TMEDA)

[0063] A solution of palladium(II) chloride (1.76 g, 10 mmol) in 50 mL of methanol was heated to reflux until dissolved, and after cooling to 20 °C, 2 mL of tetramethylethylenediamine (TMEDA) was added thereto, and a yellow solid precipitated. The yellow solid was collected, washed with diethyl ether, and dried under vacuum to obtain the product (2.5 g, yield 90%).

[0064] PdMe 2 Preparation of PdMe(TMEDA)

[0065] PdCl 2(TMEDA) (2.37 g, 8 mmol) was dispersed in 30 mL of diethyl ether and cooled to -30 °C, and a diethyl ether solution of methyllithium (12 mL, 1.44 M) was added dropwise thereto. The temperature was gradually raised to 0 °C during stirring and maintained for 1 hour, and a grayish-white suspension gradually formed. 10 mL of cold water was slowly added to this mixture and stirred until the diethyl ether phase became clear and the aqueous phase was black. The organic phase was separated, dried over anhydrous sodium sulfate, and concentrated in vacuo to obtain colorless crystals PdMe 2 (TMEDA) (1.2 g, yield 60%). 1 H NMR (200 MHz, CD 3 COCD 3 ) 303 K, 0.34 (s, 3H, PdMe), 2.40 (s, 6H, NMe 2 ), 2.57 (s, 2H, CH 2 ); 183 K, -0.36 (s, PdMe), 2.20 (dd, J(H,H) = 10 Hz, CHH-CHH), 2.33 (s, NMeAfe), 2.34 (s, NMeAfe), 2.96 (dd, J(H,H) = 10 Hz, CHH-CHH).

[0066] Preparation of 1a-PdTMEDA

[0067] At room temperature, phosphine sulfonic acid ligand 1a (1 g, 2.49 mmol) and PdMe 2 (TMEDA) (0.63 g, 2.49 mmol) were dissolved in dioxane, and with the generation of bubbles, the product rapidly precipitated from the solution. After the mixture was stirred for an additional 60 minutes, it was filtered, and the solid phase was washed with diethyl ether and dried under reduced pressure to obtain 1a-PdTMEDA (1.4 g, yield 98%) 1 H NMR (400 MHz, DMSO-d6) δ = 7.7 - 6.8 (m, 20H), 6.35 (m, 4H), 3.49 (s, 12H, OCH3), 2.30 (s, 4H, NCH2), 2.13 (s, 12H, NCH3), 0.10 (6H, Pd-CH3).

[0068] Preparation of PSPd-1

[0069] At room temperature, 1a-PdTMEDA (115 mg, 0.20 mmol) was suspended in 50 mL of dimethyl sulfoxide and stirred, and then the solvent was removed by vacuum concentration. This process was repeated until the solid was completely dissolved in DMSO. It was concentrated under reduced pressure, and diethyl ether was added to the remaining solid, and the solid was filtered (90.1 mg, yield 76%) 11H NMR (600 MHz, CD2Cl2, 25 °C): δ 8.06 (ddd, 3JHH = 8.0 Hz, 4JPH = 4.9, 4JHH = 1.0, 1H, 6-H), 7.55 (vt, J = 7.6, 2H, 10-H), 7.48 (vt, J = 7.5, 2H, 12-H), 7.45 (br, 1H, 5-H), 7.31 (vt, J = 7.6, 1H, 4-H), 7.25 (ddd, 3JHH = 11.3。

[0070] Other catalysts were prepared by changing the structure of the phosphonic acid ligand according to the above preparation method.

[0071] Examples 1-4

[0072] This example is used to illustrate the ethylene / (meth)acrylate copolymer of the present invention and its preparation method. The preparation is carried out in a 1.8 L reactor, which is equipped with mechanical stirring and a jacket, connected to an ethylene pipeline, and the reaction temperature is regulated by the oil bath temperature in the jacket.

[0073] The preparation method is as follows:

[0074] (1) According to the conditions in Table 1, methyl acrylate (MA) and 2,6-di-tert-butyl-4-methylphenol (BHT) were premixed for 5 minutes to obtain a premix.

[0075] (2) 1000 mL of toluene, 0.084 g of palladium (II) 2-(bis(2-methoxyphenyl)phosphino)benzenesulfonate (PSPd-1) and the premix were added into the reactor. The temperature in the reactor was set at 80 °C, ethylene was continuously introduced into the reactor, and the reactor pressure was set at 10 bar. After half an hour, the addition of ethylene was stopped, and acidified ethanol was injected to terminate the reaction. After depressurization, the reaction solution was poured into a flask, the solvent and unreacted monomers were evaporated, and it was placed in a vacuum oven and dried at 70 °C for 24 hours. The polymerization results and characterization data are shown in Table 1.

[0076] Table 1

[0077]

[0078] Examples 5-8

[0079] This example is used to illustrate the ethylene / (meth)acrylate of the present invention and its preparation method. The preparation is carried out in a 1.8 L reactor, which is equipped with mechanical stirring and a jacket, connected to an ethylene pipeline, and the reaction temperature is regulated by the oil bath temperature in the jacket.

[0080] The preparation method is as follows:

[0081] (1) According to the conditions in Table 2, methyl acrylate (MA) and 2,6-di-tert-butyl-4-methylphenol (BHT) were premixed for 5 minutes to obtain a premix.

[0082] (2) 1000 mL of toluene, 0.092 g of palladium (II) bis(2-phenoxyphenyl)phosphine benzenesulfonate (PSPd-2), and the premix were added into a reactor. The temperature in the reactor was set at 80 °C, ethylene was continuously introduced into the reactor, and the reactor pressure was set at 10 bar. After half an hour, the addition of ethylene was stopped, and acidified ethanol was injected to terminate the reaction. After depressurization, the reaction solution was poured into a flask, the solvent and unreacted monomers were evaporated, and it was placed in a vacuum oven and dried at 70 °C for 24 hours. The polymerization results and characterization data are shown in Table 2.

[0083] Table 2

[0084]

[0085] Examples 9-10

[0086] Copolymers were prepared according to the method of Example 1-2, except that an equimolar amount of methyl methacrylate (MMA) was added instead of methyl acrylate as the comonomer to obtain ethylene / methyl methacrylate copolymers. The polymerization conditions, results, and characterization data are shown in Table 3.

[0087] Example 11

[0088] Copolymers were prepared according to the method of Example 3, except that an equimolar amount of n-butyl acrylate (BA) was added instead of methyl acrylate as the comonomer to obtain ethylene / n-butyl acrylate copolymers. The polymerization conditions, results, and characterization data are shown in Table 3.

[0089] Table 3

[0090]

[0091] Examples 12-14

[0092] Copolymers were prepared according to the method of Example 2, except that different component b was used instead of BHT to obtain ethylene / methyl acrylate copolymers. The polymerization conditions, results, and characterization data are shown in Table 4.

[0093] Example 15

[0094] Copolymers were prepared according to the method of Example 2, except that the polymerization temperature was 100 °C and the pressure was 1.2 MPa to obtain ethylene / methyl acrylate copolymers. The polymerization conditions, results, and characterization data are shown in Table 4.

[0095] Example 16

[0096] The copolymer was prepared according to the method of Example 2, except that the temperature of the polymerization reaction was 60 °C and the pressure was 0.8 MPa to obtain an ethylene / methyl acrylate copolymer. The polymerization conditions, results and characterization data are shown in Table 4.

[0097] Table 4

[0098]

[0099] Examples 17-20

[0100] The copolymer was prepared according to the methods of Examples 1-4, except that the comonomer was not premixed with component b, but the respective components were directly added to the reactor for mixing. The polymerization results and characterization data are shown in Table 5.

[0101] Table 5

[0102] Example Content of comonomer in product (mol%) Proportion inserted into main chain (mol%) 17 9.2 72.3 18 5.3 76.5 19 7.8 74.2 20 9.8 79.3

[0103] Comparative Examples 1-4

[0104] The copolymer was prepared according to the methods of Examples 17-20, except that component b was not added. The polymerization results and characterization data are shown in Table 6.

[0105] Table 6

[0106] Comparative Example Content of comonomer in product (mol%) Proportion inserted into main chain (mol%) 1 3.1 31.3 2 2.2 36.2 3 2.8 33.8 4 3.2 38.5

[0107] Table 7 shows the polymerization activity data of some examples and comparative examples.

[0108] Table 7

[0109] Example / Comparative Example <![CDATA[Activity (10 4 g mol -1 h -1 )]]> Example 1 45 Example 2 10 Example 3 13 Example 4 18 Example 17 31 Example 18 7 Example 19 9 Example 20 14 Comparative Example 1 18 Comparative Example 2 5 Comparative Example 3 7 Comparative Example 4 12

[0110] Test Example 1

[0111] The solubility of the copolymers prepared in the test examples and comparative examples was tested.

[0112] 1 g of the copolymer was added to a vial containing 5 g of toluene or heptane, heated to 60 °C and stirred for 30 minutes. The undissolved solid was filtered off, the solvent was evaporated, the solute was weighed, and the solubility was calculated. The results are shown in Table A.

[0113] Table A

[0114]

[0115]

[0116] Examples 21-42 and Comparative Examples 5-8

[0117] Quenching effects of the copolymers prepared in Test Examples 1 - 20 and Comparative Examples 1 - 4.

[0118] Add 5 mL of hexane and 1 mg of rac-Me 2 Si(2-Me-4-Ph-Ind) 2 ZrCl 2 and 2 mg of [PhNMe 2 H][B(C 6 F 5 ) 4 into a vial. Then add the toluene solution of the copolymers prepared in Test Examples 1 - 20 at 5 wt% to the vial and stir for 5 minutes. Then, add 1 mL of 1-hexene to each vial, stir at 60 °C for half an hour, then evaporate the liquid in the vial to dryness, weigh the residual solid, and calculate the hexene conversion rate. Comparative Example 9 is the same as Test Examples 21 - 42 except that the ethylene / (meth)acrylate copolymer is not added. The quenching results are shown in Table B.

[0119] Table B

[0120]

[0121]

[0122] It can be seen from the data in Table B that the ethylene / (meth)acrylate copolymer of the present invention has excellent catalyst quenching effect.

[0123] The embodiments of the present invention have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

[0124] The endpoints and any values disclosed in this document are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this document.

Claims

1. An ethylene / (meth)acrylate copolymer, characterized in that, the copolymer comprises 85 to 95 mol% of structural units derived from ethylene and 5 to 15 mol% of structural units derived from (meth)acrylate; the number-average molecular weight of the copolymer is between 2000 and 5500 g / mol; the proportion of (meth)acrylate inserted into the main chain of the copolymer is above 70 mol%.

2. The ethylene / (meth)acrylate copolymer according to claim 1, wherein, the copolymer comprises 88 to 94 mol% of structural units derived from ethylene and 6 to 12 mol% of structural units derived from (meth)acrylate; the number-average molecular weight of the copolymer is between 2500 and 3500 g / mol; the proportion of (meth)acrylate inserted into the main chain of the copolymer is above 80 mol%, preferably above 85 mol%, more preferably above 90 mol%.

3. The ethylene / (meth)acrylate copolymer according to claim 1, wherein, the solubility of the copolymer in a hydrocarbon solvent at 60 °C is greater than 0.35 wt%.

4. The ethylene / (meth)acrylate copolymer according to claim 3, wherein, the solubility of the copolymer in an aromatic hydrocarbon solvent at 60 °C is greater than 0.8 wt%, preferably greater than 1.5 wt%, further preferably greater than 5 wt%, more preferably greater than 10 wt%.

5. The ethylene / (meth)acrylate copolymer according to claim 3, wherein, the solubility of the copolymer in an aliphatic hydrocarbon solvent at 60 °C is greater than 0.35 wt%, preferably greater than 0.5 wt%, further preferably greater than 0.6 wt%, more preferably greater than 0.8 wt%.

6. The ethylene / (meth)acrylate copolymer according to any one of claims 1-5, wherein, the (meth)acrylate is at least one of the compounds represented by formula (A), In formula (A), R a is a hydrogen atom or a methyl group, and R b is a linear or branched C 1 -C 10 alkyl group, preferably a linear or branched C 1 -C 8 alkyl group; preferably, the (meth)acrylate is at least one of methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate and 2-ethylhexyl methacrylate.

7. A process for preparing the ethylene / (meth)acrylate copolymer according to any one of claims 1-6, the process comprises: in the presence of a catalyst system, copolymerizing ethylene and (meth)acrylate present in an inert solvent, and then separating the resulting copolymer from the solvent; wherein the catalyst system comprises: (i) Component a, the main catalyst, selected from at least one of the compounds represented by formula (I); In formula (I), R 1 , R 2 , R 3 are the same or different and each independently is a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group, these groups being linear, branched or cyclic and optionally further substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group, and L is a ligand; (ii) Component b, selected from at least one of the compounds represented by formula (II) and the compounds represented by formula (III): In formula (II), R 4 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group, these groups being linear, branched or cyclic and optionally further substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 1 -C 6 carbonyl group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group; In formula (III), R 5 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 20 hydrocarbyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group or a substituted or unsubstituted C 6 -C 20 aryloxy group, these groups being linear, branched or cyclic and optionally further substituted by a halogen atom, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a C 1 -C 6 carbonyl group, a C 6 -C 10 aryl group or a C 6 -C 10 aryloxy group.

8. The preparation method according to claim 7, wherein, In formula (I), R 1 and R 2 and R 3 are the same or different and each independently is a hydrogen atom, a substituted or unsubstituted C 1 -C 10 hydrocarbyl group, a substituted or unsubstituted C 1 -C 10 alkoxy group or a substituted or unsubstituted C 6 -C 10 aryloxy group, and these groups are linear, branched or cyclic and are optionally further substituted by a halogen atom, a C 1 -C 6 alkyl group, a C 1 -C 6 alkoxy group, a C 6 -C 8 aryl group or a C 6 -C 8 aryloxy group, L is Me 2 SO; preferably, R 1 and R 2 and R 3 are the same or different and each independently is a hydrogen atom, a substituted or unsubstituted C 1 -C 6 alkyl group, a substituted or unsubstituted C 1 -C 6 alkoxy group or a substituted or unsubstituted C 6 -C 8 aryloxy group, and these groups are linear, branched or cyclic and are optionally further substituted by a halogen atom, a C 1 -C 6 alkyl group, a C 1 -C 6 alkoxy group, a C 6 -C 8 aryl group or a C 6 -C 8 aryloxy group.

9. The preparation method according to claim 8, wherein, The component a is at least one of palladium 2-(bis(2-methoxyphenyl)phosphino)benzenesulfonate, palladium 2-(bis(2-phenoxyphenyl)phosphino)benzenesulfonate, and palladium 2-(bis(2-methoxyphenyl)phosphino)-4-methylbenzenesulfonate).

10. The preparation method according to claim 7, wherein, In formula (II), R 4 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 10 alkyl group, a substituted or unsubstituted C 8 -C 16 conjugated cycloalkyl group, a substituted or unsubstituted C 1 -C 10 alkoxy group or a substituted or unsubstituted C 6 -C 10 aryloxy group, and is optionally further substituted by a halogen atom, a C 1 -C 6 alkyl group, a C 1 -C 6 alkoxy group, a C 1 -C 3 carbonyl group, a C 6 -C 8 aryl group or a C 6 -C 8 aryloxy group; In formula (III), R 5 is selected from a hydrogen atom, a substituted or unsubstituted C 1 -C 10 alkyl group, a substituted or unsubstituted C 8 -C 16 conjugated cycloalkyl group, a substituted or unsubstituted C 1 -C 10 alkoxy group or a substituted or unsubstituted C 6 -C 10 aryloxy group, and these groups are linear, branched or cyclic and are optionally further substituted by a halogen atom, a C 1 -C 6 alkyl group, a C 1 -C 6 alkoxy group, a C 1 -C 3 carbonyl group, a C 6 -C 8 aryl group or a C 6 -C 8 aryloxy group.

11. The preparation method according to claim 10, wherein, The component b is at least one of 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butylphenol, 2,4,6-tri-tert-butylphenol, and 2,6-di-tert-butyl-α-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadienylidene)-p-tolyloxy radical.

12. The preparation method according to any one of claims 7-11, wherein, The inert solvent is an aliphatic hydrocarbon solvent and / or an aromatic hydrocarbon solvent; preferably C 6 -C 12 alkane and / or C 6 -C 10 monocyclic aromatic hydrocarbon; the C 6 -C 12 alkane is preferably at least one of n-hexane, iso-hexane, n-heptane, iso-heptane, n-octane, iso-octane, and cyclohexane; the C 6 -C 10 monocyclic aromatic hydrocarbon is preferably toluene and / or xylene; preferably, the inert solvent is at least one of n-hexane, iso-hexane, cyclohexane, and toluene.

13. The preparation method according to any one of claims 7-11, wherein, The (meth)acrylate is premixed with the component b in the catalyst system, and the premixing time is preferably 1 to 30 minutes, more preferably 2 to 15 minutes, and further preferably 3 to 10 minutes.

14. The preparation method according to any one of claims 7-11, wherein, In the copolymerization reaction system, the concentration of the (meth)acrylate is 5 mol / L or less, preferably 2 mol / L or less, and more preferably 1 mol / L or less.

15. The preparation method according to any one of claims 7-11, wherein, The molar ratio of the (meth)acrylate to the component b in the catalyst system is 50:1 to 500:1, preferably 100:1 to 350:1, and more preferably 150:1 to 300:

1.

16. The preparation method according to any one of claims 7-11, wherein, In the catalyst system, the molar ratio of the component a to the component b based on Pd atoms is 1:1 to 1:200, preferably 1:3 to 1:100, more preferably 1:4 to 1:50, and further preferably 1:5 to 1:

30.

17. The preparation method according to any one of claims 7-11, wherein, The temperature of the copolymerization is 20 to 150 °C, preferably 40 to 120 °C, and more preferably 60 to 100 °C; the pressure of the copolymerization is 10 MPa or less, preferably 0.01 to 5 MPa, and more preferably 0.1 to 2 MPa.

18. The application of the ethylene / (meth)acrylate copolymer according to any one of claims 1-6 in olefin solution polymerization.

19. The application according to claim 18, wherein, The ethylene / (meth)acrylate copolymer is used as a quenching agent.

20. An olefin solution polymerization method, comprising the following steps: In the presence of a solvent, a catalyst, and the ethylene / (meth)acrylate copolymer according to any one of claims 1-6, a polymerization monomer is subjected to a polymerization reaction.

21. The olefin solution polymerization method according to claim 20, wherein, The amount of the copolymer added is at most 100 mol, preferably at most 50 mol, more preferably at most 30 mol, based on the molar amount of the comonomer in the copolymer per mole of the catalyst.

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