CN116333202B - A method for efficiently preparing ethylene-maleic anhydride alternating copolymer - Google Patents
A method for efficiently preparing ethylene-maleic anhydride alternating copolymerInfo
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- CN116333202B CN116333202B CN202310395202.XA CN202310395202A CN116333202B CN 116333202 B CN116333202 B CN 116333202B CN 202310395202 A CN202310395202 A CN 202310395202A CN 116333202 B CN116333202 B CN 116333202B
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- maleic anhydride
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
- C08F210/02—Ethene
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F222/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides, or nitriles thereof
- C08F222/04—Anhydrides, e.g. cyclic anhydrides
- C08F222/06—Maleic anhydride
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Abstract
本发明提供了路易斯酸在制备乙烯‑马来酸酐交替共聚物中的应用。本发明将助催化剂路易斯酸引入共聚合催化体系中，大幅提高了乙烯与马来酸酐的共聚合活性，降低了聚合温度，缩短了聚合反应时间，显著降低了乙烯压力，降低了能耗，避免了高压生产设备，提高了生产运营时的安全系数，进而提高了单体转化率，显著提高了生产效率。而且本发明提供制备方法，简单易行，工艺条件温和，更加适于工业化生产和推广应用。The present invention provides the application of Lewis acid in preparing ethylene-maleic anhydride alternating copolymer. The present invention introduces a co-catalyst Lewis acid into a copolymerization catalytic system, greatly improves the copolymerization activity of ethylene and maleic anhydride, reduces polymerization temperature, shortens polymerization reaction time, significantly reduces ethylene pressure, reduces energy consumption, avoids high-pressure production equipment, improves the safety factor during production operation, and then improves monomer conversion, significantly improves production efficiency. Moreover, the present invention provides a preparation method, which is simple and easy, has mild process conditions, and is more suitable for industrial production and promotion and application.
Description
Technical Field
The invention belongs to the technical field of preparation of ethylene-maleic anhydride alternating copolymers, relates to application of Lewis acid in preparation of ethylene-maleic anhydride alternating copolymers and a preparation method of the ethylene-maleic anhydride alternating copolymers, and particularly relates to application of Lewis acid in preparation of the ethylene-maleic anhydride alternating copolymers and a high-efficiency preparation method of the ethylene-maleic anhydride alternating copolymers.
Background
The ethylene-maleic anhydride alternating copolymer is an alternating copolymer with a copolymerization ratio of ethylene to maleic anhydride of 1:1, and has high thermal stability and good mechanical properties. The polymer main chain contains a large amount of cyclic anhydride groups with high reactivity, and chain extension reaction, such as reaction with amino groups in nylon molecular chains, can be easily carried out to improve the molecular weight, mechanical property and freezing resistance stability of nylon. The polymers are also widely used in adhesive and coating applications, including laminating adhesives, multilayer packaging, hot melt adhesives, wood composites, gap filling, and the like. The low molecular weight ethylene maleic anhydride copolymer may be melted or dissolved in water or solvent to meet many application requirements for liquid applications.
At present, commercial ethylene-maleic anhydride copolymer is mostly obtained by grafting maleic anhydride with polyethylene random copolymer, and representative brands are Fusabond M603 of American Dow company and AC573P of Honival company, and the commercial ethylene-maleic anhydride copolymer can be used as a compatilizer for wood-plastic composite processing and halogen-free flame-retardant wires and cables, and can also be used as a tackifier for vinyl coating to enhance the binding force with aluminum foil, stainless steel, glass, PP, PVC and other materials. The ethylene maleic anhydride copolymer has high market occupation rate, but has the defect of low grafting rate, and cannot be effectively chain-extended. Whereas the ethylene-maleic anhydride alternating copolymer overcomes the above drawbacks. At present, the ethylene-maleic anhydride alternating copolymer is mainly polymerized at high temperature and high ethylene pressure for a long time (Polymer Science U.S. S. R.1983,9, 2151-2160), the production conditions are very harsh, and the production cost is high, which greatly limits the production scale and practical application.
Therefore, how to develop a synthesis method of ethylene maleic anhydride alternating copolymer with mild reaction conditions and low cost, which solves the above problems existing in the prior art, has become one of the focus of attention of many leading researchers in the field.
Disclosure of Invention
In view of the above, the technical problem to be solved by the present invention is to provide the use of lewis acid in the preparation of ethylene-maleic anhydride alternating copolymer and a method for preparing ethylene-maleic anhydride alternating copolymer, especially an efficient method for preparing ethylene-maleic anhydride alternating copolymer. The invention has the advantages of greatly improving the copolymerization activity of ethylene and maleic anhydride after introducing Lewis acid into a polymerization system, shortening the polymerization time, reducing the ethylene pressure, along with simple preparation process, mild condition and strong controllability, and is beneficial to industrial application and commercial popularization.
The present invention provides the use of lewis acids in the preparation of ethylene-maleic anhydride alternating copolymers.
Preferably, the ethylene-maleic anhydride alternating copolymer is prepared by copolymerizing maleic anhydride monomers with ethylene;
The molar ratio of the Lewis acid to the maleic anhydride is (0.1-90): 100;
the lewis acid includes one or more of an organoaluminum compound, an organoboron compound, an organogallium compound, an organozinc compound, a boron trihalide, an aluminum trihalide, a zinc halide, and an iron halide.
Preferably, the application comprises the use of a lewis acid in combination with a free radical initiator;
the action of the lewis acid includes increasing the decomposition rate of the radical initiator and increasing the lifetime of the radical initiator;
The application is particularly the application for improving the preparation efficiency of the ethylene-maleic anhydride alternating copolymer.
Preferably, the use comprises in particular under the combined action of a Lewis acid and a free radical initiator and anhydrous and oxygen-free conditions;
The free radical initiator comprises an organic peroxide and/or an azo compound;
the molar ratio of the free radical initiator to the maleic anhydride is (0.1-90): 100;
the lewis acid acts as a cocatalyst.
Preferably, the lewis acid specifically includes one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, dichloroethylaluminum, diethylaluminum chloride, boron trihalide, aluminum trihalide, gallium trihalide, zinc dihalide, tris (pentafluorophenyl) boron, triphenylboron, tris (p-fluorophenyl) boron, tris (o-fluorophenyl) boron, tris (2, 6-difluorophenyl) boron, tris (3, 5-trifluoromethylphenyl) boron, tris (pentafluorophenyl) aluminum, triphenylaluminum, tris (pentafluorophenyl) gallium and bis (pentafluorophenyl) zinc;
The free radical initiator specifically comprises one or more of dibenzoyl peroxide, azodiisobutyl cyanide, tert-butyl peroxy-2-ethyl hexanoate, lauroyl peroxide, 1-bis (tert-amyl peroxy) cyclohexane, 1-bis (tert-amyl peroxy) -3, 5-trimethylcyclohexane, dicumyl peroxide, tert-amyl peroxyacetate and tert-amyl peroxybenzoate;
The ethylene-maleic anhydride alternating copolymer is an alternating copolymer with a copolymerization ratio of ethylene to maleic anhydride of 1:1.
The invention provides a preparation method of an ethylene-maleic anhydride alternating copolymer, which comprises the following steps:
Under the action of Lewis acid and free radical initiator, maleic anhydride monomer and ethylene are co-reacted in reaction medium under anhydrous and anaerobic condition to obtain ethylene-maleic anhydride copolymer.
Preferably, the reaction medium comprises one or more of an alkane solvent, an arene solvent, a haloalkane solvent, and a haloarene solvent;
the concentration of the maleic anhydride monomer in the reaction medium is 0.1-5.0 mol/L;
The pressure of the ethylene is 1.0-300.0 bar.
Preferably, the molar ratio of the Lewis acid to the maleic anhydride is (0.1-90): 100;
The lewis acid comprises one or more of an organoaluminum compound, an organoboron compound, an organogallium compound, an organozinc compound, a boron trihalide, an aluminum trihalide, a zinc halide, and an iron halide;
the reaction medium comprises one or more of pentane, n-hexane, petroleum ether, cyclohexane, benzene, toluene, xylene, chlorobenzene, and decalin.
Preferably, the free radical initiator comprises an organic peroxide and/or an azo compound;
the molar ratio of the free radical initiator to the maleic anhydride is (0.1-90): 100;
The ethylene-maleic anhydride alternating copolymer is an alternating copolymer with a copolymerization ratio of ethylene to maleic anhydride of 1:1.
Preferably, the time of the copolymerization reaction is 0.1-24 hours;
The temperature of the copolymerization reaction is 30-160 ℃;
the copolymerization reaction further comprises a filtering and/or drying step.
The present invention provides the use of lewis acids in the preparation of ethylene-maleic anhydride alternating copolymers. Compared with the prior art, the method aims at the problems that the production conditions existing in the actual preparation process of the existing ethylene-maleic anhydride alternating copolymer are very harsh, the higher conversion rate can be achieved only by polymerizing for 15-18 hours under the ethylene pressure of 70 ℃ and 300psi, the ethylene pressure is high, the reaction period is long, the requirement on equipment is high, and the production cost is high. The invention creatively applies Lewis acid to the preparation of the ethylene-maleic anhydride alternating copolymer by copolymerization of ethylene and maleic anhydride, and in the reaction process, the Lewis acid can accelerate the decomposition speed of the free radical initiator, improve the content of free radicals in a reaction system, and simultaneously reduce the occurrence of free radical quenching, thereby improving the stability of the free radicals and prolonging the service life of the free radical initiator. In the route for preparing the ethylene-maleic anhydride alternation based on the existing copolymerization of ethylene and maleic anhydride, a free radical initiator is necessary to initiate polymerization, and the copolymer disclosed by the invention is matched with the free radical initiator by adopting Lewis acid, so that the conditions of influencing the action effect of the free radical initiator and the characteristics of the copolymer in similar application are avoided, the reaction effect is greatly improved, and the production aging and the production cost are greatly reduced. Meanwhile, the Lewis acid can activate the maleic anhydride monomer, the activated maleic anhydride double bond lacks electrons, the polarization effect of the monomer is enhanced, and the monomer is easier to be subjected to alternating copolymerization with ethylene, so that the ethylene-maleic anhydride copolymer can be prepared more efficiently under the same condition as the existing preparation process, the production efficiency of the ethylene-maleic anhydride copolymer is improved, and the cost of the ethylene-maleic anhydride copolymer is reduced.
Experimental results show that the catalyst promoter Lewis acid is introduced into the copolymerization catalyst system, so that the copolymerization activity of ethylene and maleic anhydride is greatly improved, the polymerization temperature is reduced, the polymerization reaction time is shortened, the energy consumption is reduced, the monomer conversion rate is improved, and the production efficiency is remarkably improved. The preparation method is simple and feasible, has mild process conditions, and is more suitable for industrial production and popularization and application.
Drawings
FIG. 1 is a nuclear magnetic resonance hydrogen spectrum of an ethylene-maleic anhydride alternating copolymer prepared in example 2 of the present invention;
FIG. 2 is a DSC curve of an ethylene-maleic anhydride alternating copolymer prepared in example 2 of the present invention.
Detailed Description
For a further understanding of the present invention, preferred embodiments of the invention are described below in conjunction with the examples, but it should be understood that these descriptions are merely intended to illustrate further features and advantages of the invention and are not limiting of the invention claims.
All the raw materials of the present invention are not particularly limited in their sources, and may be purchased on the market or prepared according to conventional methods well known to those skilled in the art.
All the raw materials of the present invention are not particularly limited in purity, and the present invention preferably employs analytically pure or conventional purity requirements in the field of ethylene-maleic anhydride alternating copolymer preparation.
The expression of the substituents is not particularly limited in the present invention, and all of them are well known to those skilled in the art, and those skilled in the art can correctly understand the meaning based on the general knowledge.
All raw materials of the invention, the brands or abbreviations of which belong to the conventional brands or abbreviations in the field of the related application are clear and definite, and the person skilled in the art can purchase from the market or prepare by the conventional method according to the brands, abbreviations and the corresponding application.
The present invention provides the use of lewis acids in the preparation of ethylene-maleic anhydride alternating copolymers.
In the present invention, the ethylene-maleic anhydride alternating copolymer is preferably prepared by copolymerizing maleic anhydride monomers with ethylene.
In the present invention, the molar ratio of the Lewis acid to the maleic anhydride is preferably (0.1 to 90): 100, more preferably (0.1 to 50): 100, still more preferably (0.5 to 10): 100, and still more preferably (1 to 5): 100.
In the present invention, the lewis acid preferably includes one or more of an organoaluminum compound, an organoboron compound, an organogallium compound, an organozinc compound, a trihaloboron, a trihaloaluminum, a zinc halide, and an iron halide, and more preferably an organoaluminum compound, an organoboron compound, an organogallium compound, an organozinc compound, a trihaloboron, a trihaloaluminum, a zinc halide, or an iron halide.
In the present invention, the use preferably includes the use of a lewis acid in combination with a free radical initiator. In particular, the Lewis acid according to the invention is preferred as cocatalyst.
In the present invention, the action of the lewis acid preferably includes increasing the decomposition rate of the radical initiator and increasing the life of the radical initiator.
In the present invention, the use is particularly preferably a use for improving the production efficiency of an ethylene-maleic anhydride alternating copolymer.
In the present invention, the application particularly preferably includes under the combined action of a Lewis acid and a radical initiator and under anhydrous and anaerobic conditions.
In the present invention, the radical initiator preferably includes an organic peroxide and/or an azo compound, more preferably an organic peroxide or an azo compound.
In the present invention, the molar ratio of the radical initiator to the maleic anhydride is preferably (0.1 to 90): 100, more preferably (0.5 to 60): 100, still more preferably (1 to 30): 100, still more preferably (1 to 10): 100, still more preferably (1 to 5): 100.
In the present invention, the lewis acid specifically preferably includes one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, dichloroethylaluminum, diethylaluminum chloride, boron trihalide, aluminum trihalide, gallium trihalide, zinc dihalide, tris (pentafluorophenyl) boron, triphenylboron, tris (p-fluorophenyl) boron, tris (o-fluorophenyl) boron, tris (2, 6-difluorophenyl) boron, tris (3, 5-trifluoromethylphenyl) boron, tris (pentafluorophenyl) aluminum, triphenylaluminum, tris (pentafluorophenyl) gallium and bis (pentafluorophenyl) zinc, more preferably trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, dichloroethylaluminum, diethylaluminum chloride, boron trihalide, aluminum trihalide, gallium trihalide, zinc dihalide, tris (pentafluorophenyl) boron, triphenylboron, tris (p-fluorophenyl) boron, tris (o-fluorophenyl) boron, tris (2, 6-difluorophenyl) boron, tris (3, 5-trifluorophenyl) aluminum, tris (pentafluorophenyl) zinc, or pentafluorophenyl) zinc.
In the present invention, the radical initiator specifically preferably includes one or more of dibenzoyl peroxide, azobisisobutyronitrile, t-butyl peroxy-2-ethylhexanoate, lauroyl peroxide, 1-bis (t-amyl peroxy) cycloalkane, 1-bis (t-amyl peroxy) -3, 5-trimethylcyclohexane, dicumyl peroxide, t-amyl peroxyacetate and t-amyl peroxybenzoate, more preferred are dibenzoyl peroxide, azobisisobutyronitrile, t-butyl peroxy 2-ethylhexanoate, lauroyl peroxide, 1-bis (t-amyl peroxy) cycloalkane, 1-bis (t-amyl peroxy) -3, 5-trimethylcyclohexane, dicumyl peroxide, t-amyl peroxyacetate or t-amyl peroxybenzoate.
In the present invention, the ethylene-maleic anhydride alternating copolymer is preferably an alternating copolymer having a copolymerization ratio of ethylene to maleic anhydride of 1:1.
The invention provides a preparation method of an ethylene-maleic anhydride alternating copolymer, which comprises the following steps:
Under the action of Lewis acid and free radical initiator, maleic anhydride monomer and ethylene are co-reacted in reaction medium under anhydrous and anaerobic condition to obtain ethylene-maleic anhydride copolymer.
In the present invention, the reaction medium preferably includes one or more of an alkane solvent, an aromatic hydrocarbon solvent, a halogenated alkane solvent, and a halogenated aromatic hydrocarbon solvent, more preferably an alkane solvent, an aromatic hydrocarbon solvent, a halogenated alkane solvent, or a halogenated aromatic hydrocarbon solvent.
In the present invention, the concentration of the maleic anhydride monomer in the reaction medium is preferably 0.1 to 5.0mol/L, more preferably 1.0 to 4.0mol/L, and still more preferably 2.0 to 3.0mol/L.
In the present invention, the pressure of the ethylene is 1.0 to 300.0bar, more preferably 2.0 to 200.0bar, still more preferably 4.0 to 150.0bar, still more preferably 6.0 to 100.0bar, still more preferably 10.0 to 50.0bar.
In the present invention, the molar ratio of the Lewis acid to the maleic anhydride is preferably (0.1 to 90): 100, more preferably (0.1 to 50): 100, still more preferably (0.5 to 10): 100, and still more preferably (1 to 5): 100.
In the present invention, the lewis acid preferably includes one or more of an organoaluminum compound, an organoboron compound, an organogallium compound, an organozinc compound, a trihaloboron, a trihaloaluminum, a zinc halide, and an iron halide, and more preferably an organoaluminum compound, an organoboron compound, an organogallium compound, an organozinc compound, a trihaloboron, a trihaloaluminum, a zinc halide, or an iron halide.
In the present invention, the reaction medium preferably includes one or more of pentane, n-hexane, petroleum ether, cyclohexane, benzene, toluene, xylene, chlorobenzene, and decalin, more preferably pentane, n-hexane, petroleum ether, cyclohexane, benzene, toluene, xylene, chlorobenzene, or decalin.
In the present invention, the radical initiator preferably includes an organic peroxide and/or an azo compound, more preferably an organic peroxide or an azo compound.
In the present invention, the molar ratio of the radical initiator to the maleic anhydride is preferably (0.1 to 90): 100, more preferably (0.5 to 60): 100, still more preferably (1 to 30): 100, still more preferably (1 to 10): 100, still more preferably (1 to 5): 100.
In the present invention, the ethylene-maleic anhydride alternating copolymer is preferably an alternating copolymer having a copolymerization ratio of ethylene to maleic anhydride of 1:1.
In the present invention, the time for the copolymerization is preferably 0.1 to 24 hours, more preferably 1 to 20 hours, still more preferably 2 to 12 hours, still more preferably 3 to 6 hours.
In the present invention, the temperature of the copolymerization reaction is preferably 30 to 160 ℃, more preferably 50 to 140 ℃, still more preferably 60 to 120 ℃, still more preferably 60 to 100 ℃.
In the present invention, the copolymerization reaction is preferably followed by a filtration and/or drying step, more preferably a filtration or drying step.
In the present invention, the number average molecular weight of the ethylene-maleic anhydride alternating copolymer is preferably 16000 or more.
The invention is a better complete and refined integral technical scheme, further improves the copolymerization activity of ethylene and maleic anhydride, reduces the polymerization temperature, shortens the reaction time, reduces the energy consumption, and better improves the monomer conversion rate and the production efficiency, and the high-efficiency preparation method of the ethylene-maleic anhydride alternating copolymer specifically comprises the following steps:
a process for the preparation of an alternating ethylene-maleic anhydride copolymer comprising the steps of:
under the action of Lewis acid and free radical initiator and anhydrous and anaerobic condition, maleic anhydride monomer and ethylene are copolymerized in reaction medium to obtain ethylene-maleic anhydride copolymer.
Specifically, the lewis acid includes one or more of organoaluminum, organoboron, organogallium, organozinc, boron trihalide, aluminum trihalide, zinc halide, iron halide, and the like.
Specifically, the lewis acid includes one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, dichloroethylaluminum, diethylaluminum chloride, boron trihalide, aluminum trihalide, gallium trihalide, zinc dihalide, tris (pentafluorophenyl) boron, triphenylboron, tris (p-fluorophenyl) boron, tris (o-fluorophenyl) boron, tris (2, 6-difluorophenyl) boron, tris (3, 5-trifluoromethylphenyl) boron, tris (pentafluorophenyl) aluminum, triphenylaluminum, tris (pentafluorophenyl) gallium, and bis (pentafluorophenyl) zinc.
Specifically, the dosage of the Lewis acid is 0.1% -90.0% of the molar quantity of the maleic anhydride.
In particular, the free radical initiator comprises an organic peroxide and/or an azo compound.
Specifically, the free radical initiator comprises one or more of dibenzoyl peroxide (BPO), azobisisobutyronitrile (AIBN), tert-butyl peroxy-2-ethylhexanoate (TBPO), lauroyl Peroxide (LPO), 1-bis (tert-amyl peroxy) cycloalkane, 1-bis (tert-amyl peroxy) -3, 5-trimethylcyclohexane, dicumyl peroxide (DCP), tert-amyl peroxyacetate (TAPA) and tert-amyl peroxybenzoate (TAPB).
Specifically, the dosage of the free radical initiator is 0.1% -90.0% of the molar quantity of maleic anhydride.
Specifically, the reaction medium comprises an organic solvent such as alkane, arene, halogenated alkane, halogenated arene and the like.
Specifically, the organic solvent is one or more of pentane, n-hexane, petroleum ether, cyclohexane, benzene, toluene, xylene, chlorobenzene and decalin.
Specifically, the concentration of the maleic anhydride monomer is 0.1-5.0 mol/L.
Specifically, the ethylene pressure is 1.0-300.0 bar.
Specifically, the reaction time is 0.1-24 hours.
Specifically, the reaction temperature is 30-160 ℃.
Specifically, the copolymerization further comprises a filtering and/or drying step.
Further:
The preparation method of the ethylene-maleic anhydride alternating copolymer can comprise the following steps:
Under the anhydrous and anaerobic condition, adding maleic anhydride into a reaction vessel filled with an organic solvent reaction medium, fully stirring, adding Lewis acid and a free radical initiator, then reacting for 0.1-24 hours at 30-160 ℃, preparing a suspension of the ethylene-maleic anhydride copolymer, and centrifuging or filtering and vacuum drying to obtain a white solid product of the ethylene-maleic anhydride copolymer.
In particular, the lewis acid preferably includes one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, dichloroethylaluminum, diethylaluminum chloride, boron trihalide, aluminum trihalide, gallium trihalide, zinc dihalide, tris (pentafluorophenyl) boron, tris (pentafluorophenyl) aluminum, tris (pentafluorophenyl) gallium, bis (pentafluorophenyl) zinc, preferably one or more of triethylaluminum, triisobutylaluminum, trioctylaluminum, dichloroethylaluminum, diethylaluminum chloride, tris (pentafluorophenyl) boron, tris (pentafluorophenyl) aluminum, bis (pentafluorophenyl) zinc.
Specifically, the organoaluminum according to the present invention preferably includes C2-C20 paraffin trialkylaluminum, that is, C2-C20 paraffin substituted trialkylaluminum, more preferably C2-C17 paraffin trialkylaluminum, more preferably C2-C15 paraffin trialkylaluminum, more preferably C2-C12 paraffin trialkylaluminum, more preferably C2-C8 paraffin trialkylaluminum.
Specifically, the organic boron preferably comprises trialkylboron of C2-C20 alkane, namely C2-C20 alkane substituted trialkylboron, and further comprises triarylboron of C6-C12.
Specifically, the organic gallium preferably comprises C2-C20 paraffin trialkylgallium, namely C2-C20 paraffin substituted trialkylgallium, more preferably C2-C17 paraffin trialkylgallium, more preferably C2-C15 paraffin trialkylgallium, more preferably C2-C12 paraffin trialkylgallium, and more preferably C2-C8 paraffin trialkylgallium.
Specifically, the organoaluminum of the present invention preferably comprises a C2-C20 alkane dialkylzinc, i.e., a C2-C20 alkane substituted dialkylzinc, more preferably a C2-C17 alkane dialkylzinc, more preferably a C2-C15 alkane dialkylzinc, more preferably a C2-C12 alkane dialkylzinc, more preferably a C2-C8 alkane dialkylzinc.
Specifically, the molar ratio of the lewis acid to the maleic anhydride monomer is preferably 0.1% -90.0%, more preferably 0.1% -50.0%, more preferably 0.5% -10.0%, more preferably 1% -10.0%, and more preferably 1% -5.0%.
In particular, the radical initiator according to the invention preferably comprises an organic peroxide and/or an azo compound, more preferably an organic peroxide or an azo compound. The radical initiator is preferably one or more of dibenzoyl peroxide (BPO), azobisisobutyronitrile (AIBN), t-butyl peroxy-2-ethylhexanoate (TBPO), lauroyl Peroxide (LPO), 1-bis (t-amyl peroxy) cyclohexane, 1-bis (t-amyl peroxy) -3, 5-trimethylcyclohexane, dicumyl peroxide (DCP), t-amyl peroxyacetate (TAPA), t-amyl peroxybenzoate (TAPB).
In particular, the reaction medium according to the invention preferably comprises an organic solvent, in particular, the organic solvent preferably comprises one or more of pentane, n-hexane, petroleum ether, cyclohexane, benzene, toluene, xylene, chlorobenzene, decalin.
Specifically, the molar ratio of the free radical initiator to the maleic anhydride monomer is preferably 0.1% -90.0%, more preferably 0.5% -60.0%, more preferably 1% -30.0%, more preferably 1% -10.0%, more preferably 1% -5.0%.
Specifically, the ethylene pressure of the copolymerization is preferably 1.0-300.0 bar, more preferably 2.0-200.0 bar, more preferably 4.0-150.0 bar, more preferably 6.0-100.0 bar, more preferably 10.0-50.0 bar.
Specifically, the temperature of the copolymerization is preferably 30-160 ℃, more preferably 50-140 ℃, still more preferably 60-120 ℃, and still more preferably 60-100 ℃. The copolymerization temperature is associated with copolymerization time, and the higher the temperature of the copolymerization reaction is, the shorter the time is needed, and the specific temperature can be 40-130 ℃.
Specifically, the time for the copolymerization of the present invention is preferably 0.1 to 24 hours, more preferably 1 to 20 hours, still more preferably 2 to 12 hours, and still more preferably 3 to 6 hours.
In particular, the invention is a complete and refined preparation process, improves the polymerization rate and the monomer conversion rate, and is more beneficial to subsequent application, and the copolymerization is preferably further comprises a filtration and/or drying step, more preferably a filtration or drying step.
The ethylene-maleic anhydride alternating copolymer prepared by the preparation method of the ethylene-maleic anhydride copolymer provided by the invention has wide application prospects in the aspects of paint, adhesive, nylon reinforcing agents and the like. In the copolymerization system of the invention, the alternating copolymerization of maleic anhydride and ethylene is catalyzed by Lewis acid and free radical initiator to produce the ethylene-maleic anhydride alternating copolymer. And the polymerization reaction can be carried out in a wide temperature range. The copolymerization method provided by the invention effectively overcomes the limitation of the temperature and the ethylene pressure for preparing the ethylene-maleic anhydride copolymer, overcomes the defects of overhigh polymerization temperature and ethylene pressure, long reaction time period, simple process, easy operation, strong process controllability, mild condition, lower cost, environmental friendliness, simple and easy post-treatment process of the copolymer and the like in the prior art, and is favorable for industrial application and commercial popularization.
The invention provides application of Lewis acid in preparing ethylene-maleic anhydride alternating copolymer and an efficient preparation method of the ethylene-maleic anhydride alternating copolymer. The invention applies Lewis acid to the preparation of the ethylene-maleic anhydride alternating copolymer by copolymerization of ethylene and maleic anhydride, and in the reaction process, the Lewis acid can accelerate the decomposition speed of the free radical initiator, improve the content of free radicals in a reaction system, and simultaneously reduce the occurrence of free radical quenching, thereby improving the stability of the free radicals and prolonging the service life of the free radical initiator. In the route for preparing the ethylene-maleic anhydride alternation based on the existing copolymerization of ethylene and maleic anhydride, a free radical initiator is necessary to initiate polymerization, and the copolymer disclosed by the invention is matched with the free radical initiator by adopting Lewis acid, so that the conditions of influencing the action effect of the free radical initiator and the characteristics of the copolymer in similar application are avoided, the reaction effect is greatly improved, and the production aging and the production cost are greatly reduced. Meanwhile, the Lewis acid can activate the maleic anhydride monomer, the activated maleic anhydride double bond lacks electrons, the polarization effect of the monomer is enhanced, and the monomer is easier to be subjected to alternating copolymerization with ethylene, so that the ethylene-maleic anhydride copolymer can be prepared more efficiently under the same condition as the existing preparation process, the production efficiency of the ethylene-maleic anhydride copolymer is improved, and the cost of the ethylene-maleic anhydride copolymer is reduced.
Experimental results show that the catalyst promoter Lewis acid is introduced into the copolymerization catalyst system, so that the copolymerization activity of ethylene and maleic anhydride is greatly improved, the polymerization temperature is reduced, the polymerization reaction time is shortened, the energy consumption is reduced, the monomer conversion rate is improved, and the production efficiency is remarkably improved. The preparation method is simple and feasible, has mild process conditions, and is more suitable for industrial production and popularization and application.
For further explanation of the present invention, the use of the lewis acid provided in the present invention for preparing the ethylene-maleic anhydride alternating copolymer and a method for preparing the ethylene-maleic anhydride alternating copolymer will be described in detail with reference to examples, but it should be understood that these examples are carried out on the premise of the technical scheme of the present invention, and detailed embodiments and specific operation procedures are given only for further explanation of the features and advantages of the present invention, not limitation of the claims of the present invention, and the scope of protection of the present invention is not limited to the examples described below.
The source of the raw materials in the following examples is not particularly limited, and may be prepared by a preparation method well known to those skilled in the art or commercially available.
Performance test method and standard
The molecular weight of the polymer was measured using a normal temperature gel chromatograph at 40 ℃ with DMF as the mobile phase (containing 0.5wt% n nBu4 Br) and standard polystyrene as the reference.
The glass transition temperature of the polymer is tested by a Differential Scanning Calorimeter (DSC), the temperature rise and fall rate is 10 ℃ per minute, and the scanning range is 25-300 ℃.
The hydrogen spectrum structure of the polymer is measured by a Bruker AV500 nuclear magnetic resonance apparatus at 25 ℃, and the deuterated reagent is deuterated acetone or deuterated dimethyl sulfoxide.
Example 1
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of Al (C 6F5)3, 10mmolAIBN and 2L of toluene) are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 3 hours and then settled in absolute methanol.
The polymerization product M n =42000, molecular weight distribution 1.33, polymer yield 68 g.
Example 2
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 4 hours and then settled in absolute methanol.
The polymerization product M n = 37000, molecular weight distribution 1.32, polymer yield 94 g.
The ethylene-maleic anhydride alternating copolymer prepared in example 2 of the present invention was characterized.
Referring to fig. 1, fig. 1 is a nuclear magnetic resonance hydrogen spectrum of an ethylene-maleic anhydride alternating copolymer prepared in example 2 of the present invention.
Referring to fig. 2, fig. 2 is a DSC curve of the ethylene-maleic anhydride alternating copolymer prepared in example 2 of the present invention.
Example 3
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 10mmolAlEt 3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 6 hours and then settled in absolute methanol.
The polymerization product M n = 18000, molecular weight distribution 1.41, polymer yield 35 g.
Example 4
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 10mmol of Al iBu3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in a 40 ℃ oil bath for reaction for 4 hours and then settled in absolute methanol.
The polymerization product M n = 17300, molecular weight distribution 1.54, polymer yield 16 g.
Example 5
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 10mmol of AlCl 2 Et, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 4 hours and then settled in absolute methanol.
The polymerization product M n = 16000, molecular weight distribution 1.55, polymer yield 17 g.
Example 6
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer and 20mmol of Zn (C 6F5)2, 10mmolAIBN and 2L of toluene) are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 4 hours and then settled in absolute methanol.
The polymerization product M n = 39000, molecular weight distribution 1.25, polymer yield 23 g.
Example 7
Under the protection of high-purity nitrogen, 1.5mol of maleic anhydride monomer, 1mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene) are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 2 hours and then settled in absolute methanol.
The polymerization product M n = 33000, molecular weight distribution 1.45, polymer yield 58 g.
Example 8
Under the protection of high-purity nitrogen, 2mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for 2 hours to react and then settled in absolute methanol.
The polymerization product M n = 36000, molecular weight distribution 1.37, polymer yield 57 g.
Example 9
Under the protection of high-purity nitrogen, 1.5mol of maleic anhydride monomer, 50mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene) are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept at 10bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 1 hour and then settled in absolute methanol.
The polymerization product M n = 36000, molecular weight distribution 1.3, polymer yield 93 g.
Example 10
Under the protection of high-purity nitrogen, 1.5mol of maleic anhydride monomer, 10mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 60 ℃ for 2 hours for reaction and then settled in absolute methanol.
The polymerization product M n = 36800, molecular weight distribution 1.22, polymer yield 113 g.
Example 11
Under the protection of high-purity nitrogen, 1.5mol of maleic anhydride monomer, 50mmol of B (C 6F5)3, 5mmolAIBN and 2L of toluene) are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept at 50bar, and the mixture is placed in an oil bath at 60 ℃ for reaction for 1 hour and then settled in absolute methanol.
The polymerization product M n = 37000, molecular weight distribution 1.27, polymer yield 148 g.
Example 12
Under the protection of high-purity nitrogen, 1.5mol of maleic anhydride monomer, 25mmol of B (C 6F5)3, 20mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 10bar, and the mixture is placed in an oil bath at 100 ℃ for 2 hours for reaction and then settled in absolute methanol.
The polymerization product M n = 35000, molecular weight distribution 1.28, polymer yield 70 g.
Example 13
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer and 20mmol of B (C 6F5)3, 10mmolAIBN and 200mL of toluene) are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 40 ℃ for 2 hours to react, and then the mixture is settled in absolute methanol.
The polymerization product M n =45700, molecular weight distribution 1.33, polymer yield 10 g.
Example 14
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 50 ℃ for reaction for 3 hours and then settled in absolute methanol.
The polymerization product M n = 42400, molecular weight distribution 1.31, polymer yield 24 g.
Example 15
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 70 ℃ for 2 hours to react and then settled in absolute methanol.
The polymerization product M n = 32400, molecular weight distribution 1.28, polymer yield 63 g.
Example 16
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 6bar, and the mixture is placed in an oil bath at 80 ℃ for 2 hours to react and then settled in absolute methanol.
The polymerization product M n = 27000, molecular weight distribution 1.23, polymer yield 45 g.
Example 17
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept at 2bar, and the mixture is placed in an oil bath at 60 ℃ for 2 hours to react and then settled in absolute methanol.
The polymerization product M n =20700, molecular weight distribution 1.27, polymer yield 14 g.
Example 18
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept to be 4bar, and the mixture is placed in an oil bath at 60 ℃ for 2 hours to react and then settled in absolute methanol.
The polymerization product M n = 31200, molecular weight distribution 1.27, polymer yield 36 g.
Example 19
Under the protection of high-purity nitrogen, 1mol of maleic anhydride monomer, 20mmol of B (C 6F5)3, 10mmolAIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept at 20bar, and the mixture is placed in an oil bath at 60 ℃ for 2 hours to react and then settled in absolute methanol.
The polymerization product M n = 66000, molecular weight distribution 1.53, polymer yield 131 g.
Comparative example 1
Under the protection of high-purity nitrogen, 1.5mol of maleic anhydride monomer, 20mmol of AIBN and 2L of toluene are added into a polymerization bottle, the gas in the bottle is replaced by ethylene, the ethylene pressure is kept at 10bar, and the mixture is placed in a 100 ℃ oil bath for reaction for 2 hours and then settled in absolute methanol.
The polymerization product M n = 6000, molecular weight distribution 1.31, polymer yield 4 g.
The invention introduces Lewis acid into the ethylene and maleic anhydride copolymerization catalyst system, reduces the activation energy of the ethylene and maleic anhydride copolymerization reaction, thereby obviously reducing the ethylene pressure, shortening the polymerization reaction time, improving the production efficiency, avoiding high-pressure production equipment and improving the safety factor during production operation.
The use of the lewis acid provided by the present invention in the preparation of an ethylene-maleic anhydride alternating copolymer and an efficient process for the preparation of an ethylene-maleic anhydride alternating copolymer are described in detail above, and specific examples are set forth herein to illustrate the principles and embodiments of the present invention, and the description of the examples above is only intended to aid in understanding the process of the present invention and its core ideas, including the best mode, and to also enable any person skilled in the art to practice the invention, including making and using any devices or systems, and performing any incorporated methods. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims. The scope of the patent protection is defined by the claims and may include other embodiments that occur to those skilled in the art. Such other embodiments are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
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