CN113396166B - Process for preparing ethylene-carboxylic acid copolymers - Google Patents

Process for preparing ethylene-carboxylic acid copolymers Download PDF

Info

Publication number
CN113396166B
CN113396166B CN202080011447.2A CN202080011447A CN113396166B CN 113396166 B CN113396166 B CN 113396166B CN 202080011447 A CN202080011447 A CN 202080011447A CN 113396166 B CN113396166 B CN 113396166B
Authority
CN
China
Prior art keywords
carboxylic acid
solvent
ethylene
polar
mixture
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202080011447.2A
Other languages
Chinese (zh)
Other versions
CN113396166A (en
Inventor
宋寅浃
金洪赞
玉长勋
李晶娥
郑婉珠
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Aiskai Zhixin Co ltd
SK Innovation Co Ltd
Original Assignee
Aiskai Zhixin Co ltd
SK Innovation Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Aiskai Zhixin Co ltd, SK Innovation Co Ltd filed Critical Aiskai Zhixin Co ltd
Priority claimed from PCT/KR2020/001308 external-priority patent/WO2020159204A1/en
Publication of CN113396166A publication Critical patent/CN113396166A/en
Application granted granted Critical
Publication of CN113396166B publication Critical patent/CN113396166B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F210/00Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
    • C08F210/02Ethene
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00Processes of polymerisation
    • C08F2/01Processes of polymerisation characterised by special features of the polymerisation apparatus used
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00Processes of polymerisation
    • C08F2/38Polymerisation using regulators, e.g. chain terminating agents, e.g. telomerisation
    • C08F2/40Polymerisation using regulators, e.g. chain terminating agents, e.g. telomerisation using retarding agents
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof

Abstract

In the method of producing an ethylene-carboxylic acid copolymer according to an embodiment of the present invention, a carboxylic acid monomer and a polar co-solvent are introduced into a mixing unit or stored together in a supply unit, respectively, to form a mixture. The mixture and ethylene were injected into the reactor for copolymerization. The reaction kinetics of the carboxylic acid monomer and the polar co-solvent are controlled to inhibit the formation of byproducts.

Description

Process for preparing ethylene-carboxylic acid copolymers
Technical Field
The present invention relates to a process for preparing ethylene-carboxylic acid copolymers.
Background
For example, ethylene-carboxylic acid copolymers such as ethylene-acrylic acid copolymers are used in various articles such as sealants, adhesives, packaging materials, optical films and the like.
The ethylene-carboxylic acid copolymer may be prepared by polymerizing ethylene and a carboxylic acid-based compound (e.g., acrylic acid, methacrylic acid, etc.) as comonomers through a continuous reactor.
The carboxylic acid-based compound has higher self-reactivity than ethylene, and thus may self-polymerize when exposed to high temperature during supply through a flow path, a pump, a compressor, or the like. In this case, a flow path may be blocked or the like, thereby damaging the polymerization apparatus. When the driving temperature of the apparatus is lowered in order to prevent self-polymerization, crystallization of the carboxylic acid-based compound may occur.
When the carboxylic acid-based compound is supplied, a co-solvent may be used together to prevent crystallization and inhibit fouling in the equipment. However, when a polar solvent is used as the co-solvent, the polar solvent may react with the carboxylic acid-based compound to form a by-product.
Further, for example, when a continuous process is performed under severe polymerization conditions of high temperature and high pressure, it may be substantially difficult to perform detailed component analysis and reaction analysis of byproducts in a flow path.
Therefore, it is necessary to control the polymerization process and process parameters so that the self-polymerization of the carboxylic acid-based compound is prevented while additional byproducts can be suppressed.
For example, U.S. patent publication No. 6,852,792 discloses an aqueous dispersion for sealing comprising an ethylene-acrylic acid copolymer, but does not recognize the requirements of the polymerization process design as described above.
Disclosure of Invention
Technical purpose
According to one aspect of the present invention, a method of preparing an ethylene-carboxylic acid copolymer with improved process reliability and polymerization efficiency is provided.
Technical means
In a process for preparing an ethylene-carboxylic acid copolymer, a mixture of a carboxylic acid monomer and a polar co-solvent as an organic solvent is formed. The mixture and ethylene are injected into a reactor to copolymerize the mixture and ethylene. In the formation of the mixture of carboxylic acid monomer and polar cosolvent, the reaction progress index (Reaction Progress Index, RPI) defined by the following formula 1 is adjusted to 1.5 to 1.3X10 7 In the range of seconds K to control the amount of side reaction products of the carboxylic acid monomer and the polar co-solvent:
[ 1]
In formula 1, C Solvent(s) And C Monomer(s) The initial molar concentrations of the carboxylic acid monomer and the polar co-solvent, respectively, T represents the contact time of the carboxylic acid monomer with the polar co-solvent, and T represents the average contact temperature of the carboxylic acid monomer with the polar co-solvent prior to reaction with ethylene.
In some embodiments, the reaction progress index may be in the range of 14.9 to 1.3X10 5 In the range of seconds K.
In some embodiments, the mixture may be further discharged.
In some embodiments, the discharge pressure of the mixture may be greater than the mixing pressure of the carboxylic acid monomer and the polar co-solvent.
In some embodiments, the discharge pressure may be greater than the pressure in the reactor.
In some embodiments, the carboxylic acid monomer and the polar co-solvent may each be introduced into the mixing unit during formation of the mixture. In the discharging of the mixture, the mixture may be moved from the mixing unit to the discharging unit through the transport flow path, and the mixture may be discharged from the discharging unit through the discharging flow path.
In some embodiments, the temperature of the mixture may be maintained above the crystallization temperature of the carboxylic acid monomer and below the self-polymerization temperature of the carboxylic acid monomer.
In some embodiments, the mixture may be contacted with ethylene prior to injection into the reactor.
In some embodiments, a reaction inhibitor between the carboxylic acid monomer and the polar co-solvent may be injected into the mixture.
In some embodiments, the reaction inhibitor may include an amine-based compound.
In some embodiments, chain transfer agent may be further injected into the mixture through the front-end flow path of the reactor.
In some embodiments, the chain transfer agent may include a non-polar organic compound.
In some embodiments, the chain transfer agent may include methyl ethyl ketone or isobutane.
In some embodiments, the following formula 2 may be satisfied:
[ 2]
0.003mol/L≤Cs Solvent(s) Cr Solvent(s) + CTA r CTA CsC≤0.01mol/L
In formula 2, C r Solvent(s) And C r CTA The respective molar concentrations of polar co-solvent and Chain Transfer Agent (CTA) in the front-end flow path of the reactor, and Cs Solvent(s) And Cs CTA The respective chain transfer coefficients (Cs) of the polar co-solvent and chain transfer agent, respectively, relative to ethylene at 200 ℃.
In some embodiments, the carboxylic acid monomer may include acrylic acid and the polar co-solvent may include ethanol.
Effects of the invention
In the process for preparing an ethylene-carboxylic acid copolymer according to exemplary embodiments, a polar co-solvent may be used as a carrier fluid for the carboxylic acid monomer. The crystallization temperature of the mixture of polar co-solvent and carboxylic acid monomer may be lower than the crystallization temperature of the pure carboxylic acid monomer. Accordingly, a decrease in process yield or process efficiency due to crystallization or self-polymerization can be prevented.
In exemplary embodiments, parameters of the carboxylic acid monomer and the polar co-solvent may be adjusted such that side reactions between the carboxylic acid monomer and the polar co-solvent may be suppressed while properly controlling the reaction properties. Accordingly, deterioration of physical properties of the polymer product can be prevented by suppressing side reaction products generated from carboxylic acid monomers, and residual side reaction products in the product can also be prevented. In addition, the copolymerization yield, conversion, and molecular weight distribution of the product can be appropriately controlled.
In exemplary embodiments, the side reaction products can be effectively suppressed by control of the process conditions without decreasing the process efficiency and without adding a separate analysis device for the side reaction products in a high temperature and high pressure flow path, for example.
Drawings
Fig. 1 is a schematic process flow diagram illustrating a method of preparing an ethylene-carboxylic acid copolymer according to an exemplary embodiment.
Fig. 2 is a schematic process flow diagram illustrating a method of preparing an ethylene-carboxylic acid copolymer, according to some example embodiments.
Fig. 3 to 11 are graphs showing the change with time of the amount of ethyl acrylate produced.
Detailed Description
According to an exemplary embodiment of the present invention, there is provided a method for preparing an ethylene-carboxylic acid copolymer, in which a carboxylic acid monomer is supplied together with a polar co-solvent to induce copolymerization with ethylene while suppressing side reactions caused by the polar co-solvent.
Hereinafter, the present invention will be described in detail with reference to the accompanying experimental examples and drawings. However, those skilled in the art will appreciate that these embodiments described with reference to the drawings are provided for further understanding of the spirit of the invention and are not limiting of the subject matter to be protected disclosed in the detailed description and the appended claims.
Fig. 1 is a schematic process flow diagram illustrating a method of preparing an ethylene-carboxylic acid copolymer according to an exemplary embodiment.
Referring to fig. 1, a carboxylic acid monomer and a polar co-solvent may be supplied to the introduction unit. For example, the carboxylic acid monomer and the polar co-solvent may be supplied from the carboxylic acid monomer supply unit 10 and the co-solvent supply unit 20 to the mixing unit 30, respectively.
The carboxylic acid monomer may include an unsaturated carboxylic acid capable of initiating a chain polymerization reaction. In exemplary embodiments, (meth) acrylic acid or esters thereof (e.g., (meth) acrylic acid esters) may be used as the carboxylic acid monomer. In the present application, the term "(meth) acrylic" is used to include methacrylic and acrylic.
The polar co-solvent may be mixed with the carboxylic acid monomer and transferred into the reactor, and crystallization and self-polymerization of the carboxylic acid monomer may be inhibited.
For example, the crystallization temperature of the mixture of polar co-solvent and carboxylic acid monomer may be lower than the crystallization temperature of the pure carboxylic acid monomer. Therefore, it is possible to increase the allowable range of the process temperature capable of preventing crystallization, thereby lowering the operating temperature of the apparatus without causing crystallization and reducing the self-polymerization of the carboxylic acid monomer.
In exemplary embodiments, polar organic solvents such as alcohol-based solvents, ether-based solvents, ketone-based solvents, and the like may be used as the polar co-solvent. For example, ethanol, methanol, propanol, butanol, etc. may be used as the alcohol-based solvent.
In a preferred embodiment, ethanol, acetone and/or ethyl acetate may be used as polar co-solvents.
In exemplary embodiments, water may be removed from the polar co-solvent. If water is used as the polar co-solvent, the self-polymerization of the carboxylic acid monomer may be greatly accelerated. Thus, according to an embodiment of the present invention, the above-described organic solvent-based polar co-solvent may be used, so that the crystallization temperature may be lowered without accelerating self-polymerization.
However, when a polar co-solvent is used, the polar co-solvent may react with the carboxylic acid monomer to produce byproducts. For example, when acrylic acid is used as the carboxylic acid monomer and ethanol is used as the polar co-solvent, ethyl acrylate and water may be produced as byproducts resulting from the esterification reaction.
In addition, when acrylic acid is used as the carboxylic acid monomer and ethyl acetate is used as the polar co-solvent, ethyl acrylate may be produced as a by-product through a trans-esterification reaction.
Ethyl acrylate is a polymerizable material and thus can result in a reduction of the acrylic acid content in the chain when preparing ethyl-acrylic acid (EAA) copolymers. If ethyl acrylate is involved in polymerization instead of acrylic acid in the chain, the adhesiveness of the resulting copolymer product may be lowered, and the melting point may be lowered due to the inhibition of the crystal formation of the polymer by the bulky structure. The low melting point may cause blocking (blocking) phenomena to occur in which the particulate polymer products adhere to each other.
When exposed to elevated temperatures, ethyl acrylate can react with water to release ethanol by hydrolysis. Therefore, when ethyl acrylate is contained as a by-product in the copolymer product, residues such as bubbles may be generated on the surface or inside of the processed product.
In addition, ethyl acrylate is a smell-causing substance (odor-causing substance), and even a small amount causes malodor. When a large amount of ethyl acrylate is contained as a by-product, the product may not be suitable for use as, for example, a food package. Therefore, when the ethylene-carboxylic acid copolymer is used as a food packaging material or the like, the residual content of ethyl acrylate in the product is controlled to be less than 6ppm according to the European Union food contact regulations.
In addition, when calculation is performed on the assumption that 6ppm of the side reaction product remains in the final product by the plant process simulation model in order to control the side reaction product in advance, the actual side reaction product in the discharge unit 40 needs to be controlled at a level of, for example, 600ppm or less.
In addition, when ethyl acrylate is produced by the esterification reaction, water is also produced. As a result, water can accelerate dimerization and self-polymerization of carboxylic acid monomers, as described above.
In order to suppress or reduce the side effects due to the above-described side reaction caused by the use of the polar co-solvent, according to an exemplary embodiment to be described below, the mixing characteristics and the transport characteristics of the carboxylic acid monomer and the polar co-solvent in the flow path for transporting the carboxylic acid monomer and the polar co-solvent including, for example, the mixing unit 30 and the discharging unit 40 may be adjusted.
In the ethylene-carboxylic acid copolymer production process, it is not easy to predict the extent of the production of side reaction products due to the co-solvent input by pilot/laboratory equipment. In fact, when the side reaction products due to the introduction of ethanol are evaluated by pilot/laboratory tests for preparing ethylene-carboxylic acid copolymers, the residual amount of the side reaction products in the products cannot be detected. However, it was confirmed that ethyl acrylate in the final product was detected at a significant level as a result of injecting ethanol as a co-solvent into the actual polymerization process at the same molar ratio.
Thus, there is a need to control and design process variables to suppress side reaction products without the need for additional analysis equipment and reaction analysis results.
Thus, according to exemplary embodiments, the Reaction Progress Index (RPI) (to be described later) may be adjusted to inhibit side reactions between carboxylic acid monomers and polar co-solvents.
[ 1]
In formula 1, C Solvent(s) And C Monomer(s) The initial molar concentrations of carboxylic acid monomer and polar co-solvent in the flow path or storage unit through which the carboxylic acid monomer and polar co-solvent are mixed and introduced, respectively.
t represents the contact time between the carboxylic acid monomer and the polar co-solvent. For example, t may refer to the time from when the carboxylic acid monomer is introduced into mixing unit 30 with the polar co-solvent to when it is discharged from discharge unit 40 to encounter ethylene stream 55.
T may represent the average contact temperature of the carboxylic acid monomer with the polar co-solvent. For example, T may be the average temperature of the initial temperature at which the carboxylic acid monomer is mixed with the polar co-solvent in mixing unit 30 and the temperature that is raised by pressurization prior to encountering the ethylene stream after being discharged from discharge unit 40. For example, T may be an arithmetic average of the temperature in the mixing unit 30 and the temperature in the discharge flow path 45, or an arithmetic average of the temperature in the tank 65 (see fig. 2) and the temperature in the discharge flow path 80.
T andmay be a factor related to the rate of side reactions caused by the use of polar co-solvents. For example, when T and->The esterification reaction may be accelerated as the respective values are increased. t may be a factor related to the reaction time during which side reactions of the carboxylic acid monomer and the polar co-solvent may occur.
In an exemplary embodiment, the RPI may be adjusted to 1.5 to 1.3X10 7 In the range of seconds K. When the value of RPI is less than 1.5 seconds K, the effect of lowering the crystallization temperature by the polar co-solvent may not be sufficiently achieved. If RPI exceeds 1.3X10 7 In seconds K, the esterification reaction may proceed excessively, the above-mentioned side effects may occur, and the regulatory range regarding the side reaction products may be out of the way, thereby not being useful for commercial products.
In a preferred embodiment, the RPI value may be adjusted to 14.9 to 1.3X10 5 In the range of seconds K.
Can adjustT and T to satisfy the RPI range described above, and may not be limited to a specific range.
As described above, RPI, in which process factors that affect the reaction rates and process times at which the reactions may proceed at the respective reaction rates, are combined, may be used as process control variables in processes using various polar co-solvents, as described in equation 1. Therefore, it is not necessary to install a separate analysis device to suppress side reactions of carboxylic acid monomers and analyze the reaction results, and overall side reaction control can be performed.
Furthermore, by adjusting the RPI, the amount of side reaction products can be easily controlled to a desired level. For example, as described with reference to fig. 3-11, the relationship between RPI and side reaction products (e.g., ethyl acrylate) may be substantially linear. Thus, by modulation of RPI, the amount of side reaction products can be substantially finely controlled with high reliability.
Referring again to fig. 1, the carboxylic acid monomer and the polar co-solvent may be supplied to the mixing unit 30 from the carboxylic acid monomer supply unit 10 and the co-solvent supply unit 20, respectively and individually.
For example, the carboxylic acid monomer and the polar co-solvent may each enter the mixing unit 30 via the first and second flow paths 15 and 25, respectively. Thus, the esterification reaction can be suppressed by reducing the contact time between the carboxylic acid monomer and the polar co-solvent.
In some embodiments, one or more additives such as a polymerization initiator, a reaction inhibitor, an antioxidant, and the like may be supplied together to the mixing unit 30 or the tank 65.
The polymerization initiator may include initiators known in the polymerization art. For example, peroxides or peroxy compounds, azo bis-based compounds (azobis-based compounds), and the like can be used as the polymerization initiator.
A reaction inhibitor may be further included to inhibit side reactions of the carboxylic acid monomer and the polar co-solvent. For example, the reaction inhibitor may inhibit the formation of esters by competing with the alcohol.
In some embodiments, amine-based compounds may be used as reaction inhibitors. Examples of the amine-based compound may include alkylamines such as trimethylamine.
In some embodiments, the reaction inhibitor may be added in a molar ratio (input molar ratio) of 10 to the carboxylic acid monomer -6 To 10 -3 . Within the above range, esterification can be sufficiently suppressed without decreasing the polymerization efficiency.
The carboxylic acid monomer and the polar co-solvent mixed by the mixing unit 30 may move to the discharge unit 40 through the transport flow path 35 and may be discharged through the discharge flow path 45 to be copolymerized with ethylene.
The discharge unit 40 may include, for example, a discharge device such as a pump or a compressor (compressor) or the like.
In an exemplary embodiment, the temperatures (e.g., mixing temperature and discharge temperature) in mixing unit 30 and discharge unit 40 may be above the crystallization temperature of the carboxylic acid monomer and may be below the temperature at which the carboxylic acid self-polymerizes.
For example, the temperatures in the mixing unit 30 and the discharging unit 40 may each be adjusted in a range of 20 ℃ to 100 ℃.
In an exemplary embodiment, the discharge pressure of the carboxylic acid monomer and the polar co-solvent (e.g., from discharge unit 40) may be greater than the inlet pressure or mixing pressure in mixing unit 30.
In some embodiments, the discharge pressure may be greater than the copolymerization pressure in the reactor 60.
For example, the discharge pressure may be maintained in the range of 1100 to 2500 bar. Preferably, the discharge pressure may be in the range 1300 to 2300 bar.
Ethylene may be delivered through the third flow path 55 to contact the mixture of carboxylic acid monomer and polar co-solvent supplied through the discharge flow path 45. Thereafter, copolymerization of the carboxylic acid monomer and ethylene may be carried out in reactor 60 to produce an ethylene-carboxylic acid copolymer (e.g., EAA copolymer).
In some embodiments, the polymerization initiator described above may be introduced into the reactor 60 together through the third flow path 55 or through a separate flow path.
In one embodiment, the polymerization initiator may not be introduced into the mixing unit 30, but may be introduced only into the reactor 60. Therefore, the self-polymerization of the carboxylic acid monomer can be prevented from being promoted in advance by the polymerization initiator.
In some embodiments, a chain transfer agent (chain transfer agent) can be introduced during the polymerization process through, for example, the third flow path 55. The molecular weight and molecular weight distribution of the polymer product can be easily controlled within desired ranges using chain transfer agents.
Polar cosolvents may also have a chain transfer effect on the polymerization of ethylene-carboxylic acid comonomers. Therefore, in consideration of the chain transfer coefficient (chain transfer coefficient, cs) of the polar co-solvent, the amounts of the chain transfer agent and the polar co-solvent to be charged can be controlled, so that the molecular weight and molecular weight distribution of the ethylene-carboxylic acid copolymer can be effectively controlled while the effect of injecting the polar co-solvent is achieved.
The chain transfer agent may include, for example, a nonpolar organic compound such as isobutane or propane, etc., or a polar organic compound such as methyl ethyl ketone, isopropyl aldehyde, or vinyl acetate.
In some embodiments, the polar co-solvent may also interact with chain transfer agents inside the reactor to affect molecular weight control.
In some embodiments, the input concentration of polar co-solvent (C) included in the reaction progress index may be adjusted by taking into account the concentration of polar co-solvent and the concentration of chain transfer agent at the front-end of the reactor (e.g., third flow path 55) and their respective chain transfer coefficients Solvent(s) ) So as to satisfy the range represented by the following formula 2.
[ 2]
0.003mol/L≤Cs Solvent(s) C r Solvent(s) + CTA r CTA CsC≤0.01mol/L
C r Solvent(s) And C r CTA The molar concentrations of the polar co-solvent and Chain Transfer Agent (CTA) in the front-end flow path of the reactor, respectively. Cs (cells) Solvent(s) And Cs CTA The respective chain transfer coefficients (Cs values) of the polar co-solvent and Chain Transfer Agent (CTA) with respect to ethylene at 200 ℃.
The chain transfer coefficient is a constant that represents the reactivity of the chain transfer agent that terminates the polymerization reaction of the polymer. As the value of the chain transfer coefficient becomes larger, the amount of chain transfer agent required to reduce the molecular weight of the polymer during polymerization of the polymer becomes smaller.
Specific values of chain transfer coefficients are given in the following documents: such as Polymer Science & Technology, joel R.Fried,2006,2nd ed., p.34-39,Handbook of Polymer synthesis part A,Hans R.Kricheldorf,1991,p.3-5,Polymer Science and engineering,David J.Williams,p.103-104 et al.
For example, outside the range of the chain transfer related values represented in formula 2, chain termination may be overactivated or chain extension may be overadvanced (advanced) to make it difficult to control molecular weight.
In the exemplary embodimentIn embodiments, cs is contemplated Solvent(s) And Cs CTA Can be adjusted under the condition of C r Solvent(s) And C r CTA So as to satisfy the range of formula 2, whereby the influence of the polar co-solvent on the molecular weight and molecular weight distribution of the polymer product can be controlled. For example, the concentration (C Solvent(s) ) To satisfy C of 2 r Solvent(s)
As shown in fig. 1, a mixture of carboxylic acid monomer and polar co-solvent may be mixed with ethylene prior to injection into reactor 60 to increase the polymerization efficiency in reactor 60. In one embodiment, a mixture of carboxylic acid monomer and polar co-solvent, along with ethylene, may be injected into reactor 60.
For example, the polymerization temperature in reactor 60 may be 170 ℃ to 270 ℃. The pressure in the reactor 60 may be 1100 to 2500 bar.
In exemplary embodiments, the ethylene content (e.g., the content of ethylene derived units or blocks) in the total weight of the ethylene-carboxylic acid copolymer may be 60 wt% to 98 wt%, and the carboxylic acid content (e.g., the content of carboxylic acid derived units or blocks) may be 2 wt% to 40 wt%. Within the above range, the purity decrease due to self-polymerization of the carboxylic acid monomer and the ester by-product can be sufficiently prevented. In a preferred embodiment, the ethylene content may be 75 to 97.5 wt% and the carboxylic acid content (e.g., the content of carboxylic acid derived units or blocks) may be 2.5 to 25 wt%.
For example, the weight average molecular weight of the copolymer produced by reactor 60 may be 8000 to 1000000.
According to the above-described exemplary embodiments, by controlling the reaction kinetic properties between the carboxylic acid monomer and the polar co-solvent, crystallization and self-polymerization of the carboxylic acid monomer can be reduced while suppressing side reactions. Accordingly, the above-described side effects due to by-products such as ethyl acrylate can be prevented or reduced while improving the yield and purity of the ethylene-carboxylic acid copolymer.
The above ethylene-carboxylic acid copolymers may be commercialized in the form of, for example, particles (pellet) and used for such uses as adhesive films, sealing materials, insulating coatings, packaging films, and the like.
Fig. 2 is a schematic process flow diagram illustrating a method of preparing an ethylene-carboxylic acid copolymer, according to some example embodiments.
Referring to fig. 2, the carboxylic acid monomer and the polar co-solvent may be stored and supplied together in a storage tank 65. For example, a mixture of carboxylic acid monomer and polar co-solvent may be transferred from the reservoir 65 to the discharge unit 75 via the transfer flow path 70. The mixture may be discharged from the discharge unit 75 through the discharge flow path 80.
The ethylene stored in the ethylene supply unit 50 may move through the third flow path 55 and may be contacted with the mixture of the carboxylic acid monomer and the polar co-solvent supplied through the discharge flow path 80. Thereafter, copolymerization of the carboxylic acid monomer and ethylene may be carried out in reactor 60 to produce an ethylene-carboxylic acid copolymer (e.g., EAA copolymer).
In the embodiment of fig. 2, the process may be designed and performed to meet the RPI range in accordance with the exemplary embodiments described above. For example, t in formula 1 may represent the contact time of the carboxylic acid monomer with the polar co-solvent after introduction into the storage tank 65 until contact with ethylene.
In some embodiments, chain transfer agent may be supplied through the third flow path 55 to satisfy equation 2.
Hereinafter, preferred embodiments are presented to more specifically describe the present invention. However, the following examples are only for the purpose of illustrating the present invention, and it will be apparent to those skilled in the relevant art that these examples do not limit the appended claims, but various changes and modifications can be made within the scope and spirit of the invention. Such changes and modifications are properly included in the appended claims.
Experimental example 1
To simulate the production of side reaction products by contact between carboxylic acid monomer and polar co-solvent, the amount of ethyl acrylate produced in a mixture of Acrylic Acid (AA) containing 200ppm MEHQ (hydroquinone monomethyl ether) as inhibitor, 99.5% purity, alfa-Aeser) and ethanol (EtOH) 99.5% purity, sigma Aldrich (Sigma Aldrich) was measured by sampling over time using a gas chromatograph-flame ionization detector (GC-FID) and adding an internal standard.
In experimental examples 1-1 to 1-9, etOH/AA mixing ratios and contact temperatures were adjusted as described in Table 1.
Fig. 3 to 11 are graphs showing the production amounts of ethyl acrylate over time of experimental examples 1-1 to 1-9, respectively.
As shown with reference to fig. 3 to 11, a trend of linear generation of ethyl acrylate with time can be observed. The relationship between the amount of ethyl acrylate produced (y) and time (x) obtained by linear regression analysis is shown in fig. 3 to 11, respectively.
Specifically, the higher the EtOH/AA molar ratio or the higher the reaction temperature at the same EtOH/AA molar ratio under the same temperature conditions, the more the formation of ethyl acrylate is promoted.
It is desirable to reduce the crystallization temperature of the mixture in discharge unit 40 by introducing a polar co-solvent to achieve a process window that is capable of preventing self-polymerization and crystallization of carboxylic acid monomers. Thus, in order to properly mix the carboxylic acid monomer and the polar co-solvent and supply the mixture to the reactor 60, the minimum contact time (or residence time) of the mixture is set to 0.1 seconds.
As described above, to meet the regulatory standard (regulatory standard) of 6ppm of the side reaction product (ethyl acrylate) in the final product, the allowable level of ethyl acrylate in the discharge unit 40 in the plant process simulation model was set to 600ppm.
The Reaction Progress Index (RPI) according to the shortest contact time of 0.1 seconds (lower limit) and RPI (upper limit) at a contact time corresponding to 600ppm (upper limit of ethyl acrylate formation) for each experimental example were calculated and are shown in table 1.
TABLE 1
Referring to Table 1, when RPI is adjusted to be between 1.5 and 1.3X10 7 In the range between seconds and K, it was confirmed that the amount of the side reaction product (ethyl acrylate) can be easily controlled to be equal to or less than the target value while securing a wide process operation range by introducing the polar co-solvent. When the RPI is less than 1.5, the polar co-solvent cannot be effectively introduced into the reactor. When RPI exceeds 1.3X10 7 At seconds K, the ethyl acrylate in the final product may be out of manageable regulatory limits and may cause the side effects described above.
In addition, RPI (lower limit) at which the shortest contact time was set to 1 second and RPI (upper limit) at which the actual ethyl acrylate regulatory standard of 6ppm was satisfied in order to obtain a sufficient process operating range by the polar co-solvent were calculated and are described in table 2. Specifically, the contact time corresponding to 6ppm was calculated from the relational expression of the ethyl acrylate production amount (y) according to the time (x) described in fig. 3 to 11, respectively.
TABLE 2
Referring to Table 2, it can be confirmed that when RPI is adjusted to be 14.9 and 1.3X10 5 Between seconds and K, the amount of side reaction products may be suppressed below the practical standard while the contact time of the polar co-solvent may actually be increased.
Experimental example 2
The molar concentration of the chain transfer agent and the molar concentration of the polar co-solvent at the front-end flow path of the reactor 60 were measured by a process simulation model of the polymerization process of the ethylene-acrylic acid copolymer, and the value of formula 2 described above was calculated therefrom.
TABLE 3
As described above, the molecular weight and molecular weight distribution of the copolymer can be appropriately adjusted within the numerical range of formula 2. In addition, the influence on the molecular weight distribution by using the polar co-solvent can be appropriately controlled within the numerical range of formula 2.
For example, when the value of formula 2 is less than the lower limit (0.003 mol/L), the total amount of the compound having chain transfer activity in the reactor may be insufficient, and thus the average molecular weight of the product may become excessively large or the molecular weight distribution may become excessively broad. When the value of formula 2 is larger than the upper limit (0.01 mol/L), the total amount of the compound having chain transfer activity in the reactor increases, and thus the average molecular weight of the product may become too small or the molecular weight distribution may become too narrow.
Referring to table 3, it was confirmed that the calculated value of formula 2 can be maintained within the range of formula 2 because the chain transfer effect of the polar co-solvent itself reduces the content of the chain transfer agent even if the polar co-solvent is newly introduced.

Claims (14)

1. A process for preparing an ethylene-carboxylic acid copolymer comprising the steps of:
forming a mixture of a carboxylic acid monomer and a polar co-solvent as an organic solvent without introducing ethylene, maintaining the temperature of the mixture in the range of 25-75 ℃, wherein the carboxylic acid monomer is (meth) acrylic acid or (meth) acrylic acid ester, and the polar co-solvent is selected from the group consisting of an alcohol-based solvent, an ether-based solvent, and a ketone-based solvent; and
injecting the mixture and ethylene into a reactor to copolymerize the mixture and ethylene,
wherein the step of forming a mixture of the carboxylic acid monomer and the polar co-solvent comprises adjusting a Reaction Progress Index (RPI) defined by the following formula 1 to 1.5 to 1.3X10 7 In the range of seconds K to control the amount of side reaction products of the carboxylic acid monomer and the polar co-solvent:
[ 1]
Wherein in formula 1, C Solvent(s) And C Monomer(s) The initial molar concentrations of the polar co-solvent and the carboxylic acid monomer, respectively, T represents the contact time of the carboxylic acid monomer with the polar co-solvent after mixing the carboxylic acid monomer with the polar co-solvent until contact with ethylene, and T represents the average contact temperature of the carboxylic acid monomer with the polar co-solvent before reaction with ethylene.
2. The method for producing an ethylene-carboxylic acid copolymer according to claim 1, wherein the reaction progress index is 14.9 to 1.3 x 10 5 In the range of seconds K.
3. The method of preparing an ethylene-carboxylic acid copolymer as claimed in claim 1, further comprising the step of discharging the mixture.
4. The method for producing an ethylene-carboxylic acid copolymer according to claim 3, wherein the discharge pressure of the mixture is greater than the mixing pressure of the carboxylic acid monomer and the polar co-solvent.
5. The process for preparing an ethylene-carboxylic acid copolymer as claimed in claim 4, wherein the discharge pressure is greater than the pressure in the reactor.
6. A process for preparing an ethylene-carboxylic acid copolymer according to claim 3, wherein the step of forming the mixture comprises introducing the carboxylic acid monomer and the polar co-solvent each into a mixing unit,
wherein the step of discharging the mixture comprises:
moving the mixture from the mixing unit to a discharge unit through a transport flow path; and
the mixture is discharged from the discharge unit through a discharge flow path.
7. The process for preparing an ethylene-carboxylic acid copolymer of claim 1, wherein the mixture is contacted with ethylene prior to injection into the reactor.
8. The method of preparing an ethylene-carboxylic acid copolymer according to claim 1, further comprising the step of injecting a reaction inhibitor between the carboxylic acid monomer and the polar co-solvent into the mixture.
9. The method of preparing an ethylene-carboxylic acid copolymer of claim 8, wherein the reaction inhibitor comprises an amine-based compound.
10. The method for producing an ethylene-carboxylic acid copolymer according to claim 1, further comprising the step of injecting a chain transfer agent into the mixture through a front-end flow path of the reactor.
11. The method of making an ethylene-carboxylic acid copolymer as claimed in claim 10, wherein the chain transfer agent comprises a non-polar organic compound.
12. The method of making an ethylene-carboxylic acid copolymer of claim 11, wherein the chain transfer agent comprises methyl ethyl ketone or isobutane.
13. The method for producing an ethylene-carboxylic acid copolymer according to claim 10, wherein the following formula 2 is satisfied:
[ 2]
0.003mol/L≤Cs Solvent(s) C r Solvent(s) +Cs CTA C r CTA ≤0.01mol/L
Wherein in formula 2, C r Solvent(s) And C r CTA The respective molar concentrations of the polar co-solvent and the chain transfer agent in the front-end flow path of the reactor, respectively, and
Cs solvent(s) And Cs CTA The polar co-solvent and the chain transfer agent are each relative to ethylene at 200 ℃, respectivelySelf chain transfer coefficient (Cs).
14. The method of making an ethylene-carboxylic acid copolymer of claim 1, wherein the carboxylic acid monomer comprises acrylic acid and the polar co-solvent comprises ethanol.
CN202080011447.2A 2019-02-01 2020-01-29 Process for preparing ethylene-carboxylic acid copolymers Active CN113396166B (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
KR10-2019-0013255 2019-02-01
KR20190013255 2019-02-01
KR10-2020-0006278 2020-01-17
KR1020200006278A KR20200096126A (en) 2019-02-01 2020-01-17 Method of producing ethylene-carboxylic acid compolymer
PCT/KR2020/001308 WO2020159204A1 (en) 2019-02-01 2020-01-29 Method for producing ethylene-carboxylic acid copolymer

Publications (2)

Publication Number Publication Date
CN113396166A CN113396166A (en) 2021-09-14
CN113396166B true CN113396166B (en) 2024-02-02

Family

ID=72048465

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202080011447.2A Active CN113396166B (en) 2019-02-01 2020-01-29 Process for preparing ethylene-carboxylic acid copolymers

Country Status (2)

Country Link
KR (1) KR20200096126A (en)
CN (1) CN113396166B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115651109B (en) * 2022-10-02 2024-02-02 中化国际聚合物(连云港)有限公司 Agglomeration agent for producing elastomer and preparation method thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103237823A (en) * 2010-09-30 2013-08-07 陶氏环球技术有限责任公司 Ethylene-based interpolymers and processes to make the same
CN104870481A (en) * 2012-12-28 2015-08-26 陶氏环球技术有限责任公司 Method to improve the feeding of a carboxylic acid comonomer into a high pressure reactor
CN107873035A (en) * 2015-06-30 2018-04-03 陶氏环球技术有限责任公司 High-pressure free radical polymerize

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6852792B1 (en) 2000-04-13 2005-02-08 E. I. Du Pont De Nemours And Company Coating composition containing a low MFI ethylene acrylic acid copolymer
US7598321B2 (en) * 2005-08-10 2009-10-06 E. I. Du Pont De Nemours And Company Ethylene acid copolymer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103237823A (en) * 2010-09-30 2013-08-07 陶氏环球技术有限责任公司 Ethylene-based interpolymers and processes to make the same
CN104870481A (en) * 2012-12-28 2015-08-26 陶氏环球技术有限责任公司 Method to improve the feeding of a carboxylic acid comonomer into a high pressure reactor
CN107873035A (en) * 2015-06-30 2018-04-03 陶氏环球技术有限责任公司 High-pressure free radical polymerize

Also Published As

Publication number Publication date
KR20200096126A (en) 2020-08-11
CN113396166A (en) 2021-09-14

Similar Documents

Publication Publication Date Title
EP2121592B1 (en) A free radical initiator system and a high pressure, freeradical polymerization process for producing a low density polyethylene polymer
CN104619730B (en) The manufacture method of dispersion stabilizer for suspension polymerization and vinyl resin
JP5048517B2 (en) Method for producing (meth) acrylic syrup
JP5032498B2 (en) Method for free radical polymerization of vinyl monomers
JPH07121968B2 (en) Copolymerization of ethylene with methanol
WO2012084787A1 (en) Process for the preparation of ethylene copolymers in the presence of free-radical polymerization initiator by copolymerizing ethylene, a bi- or multifunctional comonomer and optionally further comonomers
US9109064B2 (en) Ethylene polymerization process using an inhibitor
EP2673307B1 (en) Free radical polymerisation of ethylene initiated by organic peroxides with high productivity
TWI383998B (en) Herstellung von vinylacetat-vinylester-mischpolymerisaten mit geringem gehalt an hochsiedenden vinylestern
CN113396166B (en) Process for preparing ethylene-carboxylic acid copolymers
EP4209519A1 (en) Method for preparing eva copolymer with high ethylene content by solution polymerization under a low to a medium pressure
JPS6270488A (en) Additive of fuel oil and fuel oil improved in flowability
EP3119821B1 (en) Secondary suspending agent for suspension polymerisation reaction
RU2625314C2 (en) Application of mercaptomethyl complex esters as chain transmission agents
JP4249614B2 (en) High pressure polymerization of ethylene
CN112210024A (en) Lubricant composition and method for preparing copolymer using the same
SK3982001A3 (en) Continuous dosing of very fast initiators during polymerization reactions
US20220242980A1 (en) Method for Producing Ethylene-Carboxylic Acid Copolymer
JP5406596B2 (en) Method for producing polymer emulsion
CN114573736B (en) Method for reducing volatile matter content in poly (methyl) acrylic ester
TWI518100B (en) Method for producing methacrylic polymer
EP3404048B1 (en) Method for preparing vinyl chloride based polymer
CN109153744B (en) Process for producing vinyl alcohol polymer
KR100569219B1 (en) Method of reducing the content of residual monomers in emulsion polymers
WO2018115790A1 (en) Use of at least one phenolic compound to stabilise ethylene copolymerisation reactions

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
CB02 Change of applicant information

Address after: Seoul, South Kerean

Applicant after: SK INNOVATION Co.,Ltd.

Applicant after: Aiskai Zhixin Co.,Ltd.

Address before: Seoul, South Kerean

Applicant before: SK INNOVATION Co.,Ltd.

Applicant before: SK Global Chemical Co.,Ltd.

CB02 Change of applicant information
GR01 Patent grant
GR01 Patent grant