JP3882250B2 - Production method of polyvinyl imidazoline - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing polyvinyl imidazoline. Polyvinylimidazoline is a useful compound as a polymer flocculant.
[0002]
[Prior art]
As a method for producing polyvinyl imidazoline or a salt thereof by reacting a polymer of acrylonitrile or methacrylonitrile with a polyamine, a method using sulfur as a catalyst is known (Japanese Patent Publication No. 42-6271). In the method using sulfur as a catalyst, although the reaction proceeds at a temperature of 100 ° C. or lower, there is a problem that extremely toxic hydrogen sulfide is by-produced during the reaction.
[0003]
Further, as a method of reacting a nitrile compound and a polyamine to form an imidazoline ring, a copper salt (Japanese Patent Publication No. 5-39943) and a zinc salt (Japanese Patent Laid-Open No. 62-195369) are used and heated to 100 ° C. or higher. The method of making it react is known. However, in these methods, although it is known that a reaction between a nitrile compound having one or two nitrile groups and a polyamine proceeds, for example, acrylonitrile (or methacrylonitrile) having a large number of nitrile groups in the molecule. It is not known whether or not the reaction between the polymer of) and polyamine proceeds. There are many nitrile groups in the polymer of acrylonitrile (or methacrylonitrile), and it is widely known that the polymer decomposes easily when heated.
[0004]
Therefore, no method other than a method using a sulfur catalyst has been known as a method for producing polyvinyl imidazoline.
[0005]
[Problems to be solved by the invention]
As described above, the conventional method for producing polyvinyl imidazoline has a problem that hydrogen sulfide is by-produced, and is not sufficiently satisfactory industrially. Therefore, development of a production method that does not produce hydrogen sulfide as a by-product has been desired.
[0006]
[Means for Solving the Problems]
As a result of intensive studies on the production method of polyvinyl imidazoline, the present inventor has no generation of hydrogen sulfide by using a metal oxide or a carboxylic acid as a catalyst, and surprisingly, acrylonitrile (or methacrylonitrile) The inventors have found a novel fact that polyvinyl imidazoline can be produced without thermal decomposition of the polymer, and have completed the present invention.
[0007]
That is, the present invention provides a method for producing a polyvinyl imidazoline or a salt thereof by reacting a polymer containing a nitrile group with a polyamine, in the presence of a metal oxide and a carboxylic acid. Is the law.
[0008]
The present invention is described in further detail below.
[0009]
Examples of the metal oxide in the method of the present invention include aluminum oxide, silicon dioxide, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide, zinc oxide, zirconium oxide, Examples include oxides of rare earth elements such as niobium oxide, molybdenum oxide, silver oxide, cadmium oxide, indium oxide, tin oxide, tantalum oxide, tungsten oxide, rhenium oxide, lead oxide, scandium, yttrium, lanthanum, and cerium. Of these, copper oxide, chromium oxide, manganese oxide, zinc oxide and niobium oxide are particularly preferred because of their improved activity and selectivity. The oxidation degree of the metal element is not particularly limited. For example, in the case of copper, either monovalent or divalent may be used. The metal oxide may be used in a form containing water, for example, a hydroxide. Further, the metal oxide may be used by being supported on a carrier. As the carrier, oxides such as silica and alumina, composite oxides such as silica-alumina and diatomaceous earth, activated carbon, porous glass, ceramic and the like can be used.
[0010]
The metal oxide can be used by mixing with other metal oxides. For example, copper chromite, copper oxide-zinc oxide, etc. can be used.
[0011]
In the method of the present invention, the carboxylic acid is not particularly limited, but formic acid, acetic acid, propionic acid, acetic acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, lauric acid, myristic acid, palmitic acid, stearic acid, 2- Aliphatic saturated monocarboxylic acids such as ethylhexanoic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and other aliphatic saturated dicarboxylic acids, acrylic acid, propiol Aliphatic unsaturated carboxylic acids such as acid, methacrylic acid, crotonic acid, isocrotonic acid, oleic acid, elaidic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, camphoric acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid Carbocyclic such as acid, naphthoic acid, toluic acid, hydroatropic acid, atropaic acid, cinnamic acid Examples include carboxylic acids such as rubonic acids, fluoric acid, tennic acid, nicotinic acid and isonicotinic acid, polymers such as polyacrylic acid and polymethacrylic acid, monochloroacetic acid, dichloroacetic acid and trifluoroacetic acid. . In the method of the present invention, the carboxylic acid may be used in the form of a salt.
[0012]
The catalysts used in the present invention are these metal oxides and carboxylic acids or carboxylic acids. Moreover, there is no restriction | limiting in particular in the ratio of a metal oxide and carboxylic acid, and when both exist, reaction will be accelerated greatly.
[0013]
Under the conditions of the method of the present invention, since the polyamine compound is present, the system becomes strongly basic, and the metal oxide and carboxylic acid do not react to form a metal carboxylate.
[0014]
In the method of the present invention, the form of the catalyst is not particularly limited, and the metal oxide catalyst may be used as a powder or may be used after molding depending on the reaction mode. Since the metal oxide does not dissolve in the reaction product polyvinyl imidazoline, it can be easily separated and reused. Carboxylic acid may be used as a mixture with a metal oxide, or may be used as a mixture with a raw material.
[0015]
In the method of the present invention, an acrylonitrile or methacrylonitrile homopolymer may be used as the raw material containing a nitrile group, and a copolymer may also be used. Monomers that can be copolymerized with acrylonitrile or methacrylonitrile include vinyl halides such as vinyl chloride, vinyl bromide, and vinyl fluoride, vinylidene halides such as vinylidene chloride, acrylic acid, methacrylic acid, itaconic acid, and maleic anhydride. Unsaturated carboxylic acids such as acids and salts thereof, (meth) acrylic acid esters such as methyl (meth) acrylate and ethyl (meth) acrylate, unsaturated ketones such as methyl vinyl ketone and methyl isopropenyl ketone, Vinyl esters such as vinyl acetate and vinyl benzoate, vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, (meth) acrylamide and alkyl-substituted products thereof, vinyl sulfonic acid, (meth) allyl sulfonic acid, p-styrene sulfonic acid, 2 -Acrylamide-2-methyl Propane sulfonic acid, unsaturated sulfonic acid such as (meth) acryloyloxyethyl sulfonic acid and the like, and salts thereof, styrene such as styrene, α-methylstyrene, chlorostyrene, and alkyl or halogen substituted products thereof, allyl alcohol and esters thereof, or Examples thereof include basic vinyl compounds such as ethers, vinyl pyridine, vinyl pyrimidine, vinyl imidazole, dimethylaminoethyl methacrylate, and vinylbenzyl dimethylamine.
[0016]
The starting polyamine used in the process of the present invention is 1,2-diamine. 1,2-diamine is a compound represented by the following formula (1).
[0017]
H ₂ NCHR ¹ CHR ² NHR ³ (1)
(Wherein R ¹ , R ² and R ³ each independently represents hydrogen, aliphatic, araliphatic or aromatic group)
1,2-diamine includes ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, aminoethylpiperazine, and other ethyleneamines, diaminopropane, diaminobutane, diaminopentane, diaminohexane, diaminooctane, diaminononane, Diaminodecane, cyclohexylethylenediamine, benzylethylenediamine, phenylethylenediamine, methoxyphenylethylenediamine, dimethylphenylethylenediamine, tolylethylenediamine, N-cyclohexylethylenediamine, N-benzylethylenediamine, N-phenylethylenediamine, N-methoxyphenylethylenediamine, N-dimethylphenylethylenediamine, N-Tolylechi Njiamin, N- methyl ethylenediamine, N- ethyl ethylene Ji, N- isobutyl ethylenediamine, N- phenyl ethylenediamine, N- (2- aminoethyl) ethylenediamine, and the like.
[0018]
In the method of the present invention, the polymer of polyamine and acrylonitrile or methacrylonitrile can be reacted with a chemical equivalent or an excess of one.
[0019]
In the method of the present invention, the reaction temperature is usually in the range of 60 to 300 ° C. in order to improve the reaction rate, suppress the decomposition of amines and improve the yield of polyvinyl imidazoline, but it may be carried out at 70 to 250 ° C. Further preferred.
[0020]
The process according to the invention is usually carried out in the liquid phase.
[0021]
In the method of the present invention, the reaction may be carried out under normal pressure or under pressure, as long as the raw material is kept in a liquid state, a solution state or a suspension state. In this reaction, ammonia is generated during the reaction, and in the case of a pressure reaction, the pressure increases. However, this ammonia can be removed during the reaction or can be removed after the reaction is completed. . When the reaction temperature exceeds the boiling point of the raw material, a method such as carrying out the reaction under pressure, providing a condenser, or supplying the raw material little by little can be employed.
[0022]
In the method of the present invention, a solvent may or may not be used. As the solvent, it is not preferable to use a solvent that decomposes imidazoline such as water, but any solvent that is inert to the reaction conditions can be used without particular limitation.
[0023]
The method of the present invention may be carried out by continuous reaction, batch reaction or semi-batch reaction. The reaction can be carried out in a fixed bed or a suspension bed.
[0024]
Polyvinylimidazoline can be easily converted to a salt by contact with an acid. Specifically, it can be converted into polyvinyl imidazoline chloride by adding an equivalent aqueous hydrochloric acid solution to water-soluble polyvinyl imidazoline.
[0025]
In the method of the present invention, the reaction product polyvinyl imidazoline may be purified as it is or in the form of a salt.
[0026]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.
[0027]
Example 1
25 g of polyacrylonitrile (average molecular weight 86,000), 60 g of ethylenediamine, 1.5 g of activated zinc white, and 1.5 g of acetic acid were placed in a 200 ml electromagnetically stirred stainless steel autoclave and purged with nitrogen. When the temperature exceeded 100 ° C, the pressure increased to 0.3 MPa at 130 ° C. The temperature was continued to rise to 180 ° C. The autoclave pressure continued to increase and reached 1.7 MPa after 5 hours.
[0028]
When this was cooled, the viscous red solution was removed and poured into acetone to give a pale yellow solid. When this was dried, 48 g of pale yellow polyvinyl imidazoline powder was obtained. When dissolved in methanol and filtered, 1.5 g of insoluble active zinc white could be separated.
[0029]
Example 2
Polyvinylimidazoline was produced in the same manner as in Example 1 except that 40 g of N, N-dimethylformamide was used as a solvent and niobium oxide was used instead of activated zinc white. The pressure of 1.6 MPa increased in 5 hours after reaching 180 ° C.
[0030]
This was cooled and poured into acetone to a pale yellow solid. When this was dried, 39 g of pale yellow polyvinyl imidazoline powder was obtained.
[0031]
Example 3
26 g of polyacrylonitrile (average molecular weight 86,000), 60 g of ethylenediamine, 40 g of methanol, 1.5 g of copper oxide, and 1.5 g of propionic acid were placed in a 200 ml magnetically stirred stainless steel autoclave, purged with nitrogen, and then heated to 220 ° C. Warm up. The pressure reached 3.1 MPa at 220 ° C. After 30 minutes, it was cooled and a viscous brown solution was removed. This was poured into acetone and dried to give 50 g of a brown solid.
[0032]
Example 4
Acrylonitrile, 50 g of styrene copolymer (acrylonitrile 25%), 60 g of ethylenediamine, 1.5 g of activated zinc white, and 1.5 g of acetic acid were placed in a 200 ml electromagnetically stirred stainless steel autoclave, purged with nitrogen, and then heated to 180 ° C. . The pressure after 5 hours became 1.0 MPa.
[0033]
This was cooled and a viscous white solution was taken out. When poured into water, it became a white solid. When this was dried, 56 g of white vinylimidazoline styrene copolymer powder was obtained.
[0034]
Example 5
240 g of polyacrylonitrile (average molecular weight 86,000), 1200 g of ethylenediamine, and 144 g of acetic acid were placed in a 2 l flask and purged with nitrogen. After heating at 90 ° C. for 12 hours, this was cooled, and the viscous red solution was taken out and poured into acetone to give a pale yellow solid. When this was dried, 575 g of pale yellow polyvinyl imidazoline powder, part of which was acetate, was obtained.
[0035]
Example 6
5 g of polyacrylonitrile (average molecular weight 500,000), 50 g of ethylenediamine, and 1 g of acetic acid were placed in a 200 ml flask and purged with nitrogen. After heating at 90 ° C. for 12 hours, this was cooled, and the viscous red solution was removed and poured into acetone to give a white solid. When this was dried, 10 g of polyvinyl imidazoline powder partially converted to acetate was obtained.
[0036]
Example 7
5 g of polyacrylonitrile (average molecular weight 86,000), 10 g of ethylenediamine, 40 g of n-heptane, and 1.5 g of acetic acid were placed in a 200 ml flask, purged with nitrogen, and heated to 95 ° C. After reacting at 95 ° C. for 9 hours, it was cooled, poured into acetone and dried to give 9 g of a white solid.
Example 8
25 g of acrylonitrile and styrene copolymer (acrylonitrile 25%), 50 g of 1,2-propanediamine and 5 g of 2-ethylexanoic acid were placed in a 200 ml flask, purged with nitrogen, and then heated to 130 ° C. This was cooled and a viscous white solution was taken out. When poured into water, it became a white solid. When this was dried, white methylvinylimidazoline-styrene copolymer powder was obtained.
[0037]
【The invention's effect】
The present invention provides a method for producing polyvinyl imidazoline which does not produce hydrogen sulfide as a by-product and does not cause thermal decomposition of a polymer of acrylonitrile (or methacrylonitrile), and is extremely significant industrially.

Claims (8)

  A method for producing polyvinyl imidazoline, which comprises reacting a polymer containing a nitrile group with a polyamine to produce polyvinyl imidazoline or a salt thereof in the presence of a metal oxide and a carboxylic acid. A process for producing polyvinyl imidazoline or a salt thereof by reacting a polymer containing a nitrile group with a polyamine, wherein the process is carried out in the presence of a carboxylic acid (however, a nitrile-containing polymer and an alkylene) This excludes a method in which polyamine is dispersed and reacted using a hydrocarbon wax carboxylated in a hydrocarbon solvent or a polymerized fatty acid polyamide resin .   The production method according to claim 1 or 2, wherein the polymer containing a nitrile group is a homopolymer or copolymer of acrylonitrile or methacrylonitrile. The production method according to any one of claims 1 to 3, wherein the polyamine is a compound represented by the following formula (1).
H ₂ NCHR ¹ CHR ² NHR ³ (1)
(Wherein R ¹ , R ² and R ³ each independently represents hydrogen, an aliphatic group, an araliphatic group or an aromatic group)   Metal oxide is aluminum oxide, silicon dioxide, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide, zinc oxide, zirconium oxide, niobium oxide, molybdenum oxide, silver oxide, The production method according to any one of claims 1 to 4, wherein the production method is cadmium oxide, indium oxide, tin oxide, tantalum oxide, tungsten oxide, rhenium oxide, lead oxide, or an oxide of a rare earth element.   Carboxylic acid is aliphatic saturated monocarboxylic acid, aliphatic saturated dicarboxylic acid, aliphatic unsaturated carboxylic acid, carbocyclic carboxylic acid, heterocyclic carboxylic acid, polyacrylic acid, polymethacrylic acid polymer, monochloroacetic acid, The production method according to any one of claims 1 to 5, wherein the production method is dichloroacetic acid or trifluoroacetic acid.   The process according to any one of claims 1 to 6, wherein the reaction temperature is in the range of 60 to 300 ° C.   The process according to any one of claims 1 to 7, wherein the reaction is carried out in a liquid phase.