JPH1045831A - Production of polyvinylimidazoline - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a polyvinylimidazoline without generating hydrogen sulfide, without causing thermal degradation of a polymer such as acrylonitrile and useful as a polymer coagulant by using a metal salt as a catalyst. SOLUTION: This polyvinylimidazoline is produced by reacting (A) a polymer containing a nitrile group with (B) a polyamine in the presence of (c) a metal salt (preferably, an organic acid salt or an inorganic acid salt of zinc, iron, copper, cobalt, manganese, aluminum, tin, mercury, chromium or cadmium, e.g. zinc acetate). Moreover, the component A is preferably a single polymer or copolymer of acrylonitrile or methacrylonitrile, the component B is preferably a compound of the formula (R<1> to R<3> are each H, an aliphatic group, an aromatic-aliphatic group or an aromatic group) (e.g. ethylenediamine) and the reaction is preferably performed within the range of 100-300 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing polyvinylimidazoline. Polyvinyl imidazoline is a compound useful as a polymer flocculant.

[0002]

2. Description of the Related Art As a method for producing a 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).
No.). In the method using sulfur as a catalyst, although the reaction proceeds at a temperature of 100 ° C. or less, there is a problem that extremely toxic hydrogen sulfide is by-produced during the reaction.

As a method for forming an imidazoline ring by reacting a nitrile compound with a polyamine, copper salts (Japanese Patent Publication No. 5-39943) and zinc salts (JP-A-62-1) are known.
No. 95369), and a method of reacting by heating to 100 ° C. or more is known. However, in these methods, although it is known that the reaction between the nitrile compound having one or two nitrile groups and the polyamine proceeds, for example, acrylonitrile (or methacryloyl) having a large number of nitrile groups in the molecule is known. It is not known whether the reaction between the polymer of nitrile) and the polyamine proceeds. It is widely known that polymers of acrylonitrile (or methacrylonitrile) have a large number of nitrile groups and easily decompose when heated.

Therefore, as a method for producing polyvinylimidazoline, there has been no known method other than a method using a sulfur catalyst.

[0005]

As described above, the conventional method for producing polyvinyl imidazoline has a problem that hydrogen sulfide is produced as a by-product, and is not industrially satisfactory. 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 a method for producing polyvinylimidazoline, the present inventors have found that by using a metal salt as a catalyst, there is no generation of hydrogen sulfide, and surprisingly, acrylonitrile (or The present inventors have found a novel fact that polyvinylimidazoline can be produced without thermal decomposition of a polymer of (methacrylonitrile), and have completed the present invention.

That is, the present invention provides a method for producing a polyvinylimidazoline or a salt thereof by reacting a polymer having a nitrile group with a polyamine, wherein the reaction is carried out in the presence of a metal salt. It is a manufacturing method.

Hereinafter, the present invention will be described in more detail.

[0009] The catalyst used in the process of the present invention is a metal salt. Examples of the metal salt include an organic acid or an inorganic acid salt of zinc, iron, copper, cobalt, manganese, aluminum, tin, mercury, chromium, or cadmium. There is no particular limitation on the degree of oxidation of the metal element, for example, in the case of copper, monovalent,
Either divalent may be used. Further, the metal oxide may be used by being supported on a carrier. As a carrier, silica,
Oxides such as alumina, composite oxides such as silica-alumina and diatomaceous earth, activated carbon, porous glass, and ceramics can be used.

[0010] In the method of the present invention, the metal salt can be used in combination with other metal salts.

In the method of the present invention, the form of the catalyst is not particularly limited. Depending on the reaction mode, the metal salt catalyst may be used in the form of a powder or may be used after being molded.

In the method of the present invention, a homopolymer of acrylonitrile or methacrylonitrile or a copolymer may be used as the raw material containing a nitrile group. Monomers copolymerizable with acrylonitrile or methacrylonitrile include vinyl chloride, vinyl bromide, vinyl halides such as vinyl fluoride, vinylidene halides such as vinylidene chloride, acrylic acid,
Unsaturated carboxylic acids such as methacrylic acid, itaconic acid and maleic anhydride and salts thereof, (meth) acrylates such as methyl (meth) acrylate and ethyl (meth) acrylate, methyl vinyl ketone, methyl isopropenyl Unsaturated ketones such as ketones, vinyl esters such as vinyl acetate and vinyl benzoate, vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, (meth) acrylamide and its alkyl-substituted products, vinyl sulfonic acid, and (meth) allyl sulfonic acid , P-styrenesulfonic acid, 2-acrylamide-2-methylpropanesulfonic acid, unsaturated sulfonic acids such as (meth) acryloyloxyethylsulfonic acid, and salts thereof, styrene, α-
Styrene such as methylstyrene and chlorostyrene and alkyl- or halogen-substituted products thereof, allyl alcohol and esters or ethers thereof, basic vinyl compounds such as vinylpyridine, vinylpyrimidine, vinylimidazole, dimethylaminoethyl methacrylate, and vinylbenzyldimethylamine And the like.

The starting polyamine used in the method of the present invention is 1,2-diamine. 1,2-Diamine 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 represent a hydrogen, aliphatic, araliphatic or aromatic group) 1 , 2-diamines include ethyleneamine such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine and aminoethylpiperazine, diaminopropane, diaminobutane, diaminopentane, diaminohexane, diaminooctane, diaminononane, diamino Decane, cyclohexylethylenediamine, benzylethylenediamine, phenylethylenediamine, methoxyphenylethylenediamine, dimethylphenylethylenediamine, tolylethylenediamine, N-cyclohexylethylenediamine, N-benzyl Ethylenediamine, N
-Phenylethylenediamine, N-methoxyphenylethylenediamine, N-dimethylphenylethylenediamine, N-tolylethylenediamine, N-methylethylenediamine, N-ethylethylenedimine, N-isobutylethylenediamine, N-phenylethylenediamine, N
-(2-aminoethyl) ethylenediamine and the like are exemplified.

In the method of the present invention, the acrylonitrile or methacrylonitrile polymer and the polyamine can be reacted with each other in a chemical equivalent or an excess of one.

In the process of the present invention, the reaction temperature is usually in the range of 100 to 300 ° C. in order to increase the reaction rate, suppress the decomposition of amines, and increase the yield of polyvinyl imidazoline. More preferably, it is performed.

The process according to the invention is usually carried out in the liquid phase.

In the method of the present invention, the reaction can be carried out at normal pressure or under pressure, as long as the raw materials can be kept in a liquid, solution or suspension state. In this reaction, since ammonia is generated during the reaction, the pressure increases in the case of a pressurized reaction, but 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 materials, a method of performing the reaction under pressure, providing a condenser, or supplying the raw materials little by little can be employed.

In the method of the present invention, a solvent may or may not be used. It is not preferable to use a solvent that decomposes imidazoline such as water, but any solvent can be used without particular limitation as long as it is inert to the reaction conditions.

The method of the present invention may be carried out by a continuous reaction, a batch reaction or a semi-batch reaction. The reaction can be carried out on a fixed bed or a suspension bed.

[0021] Polyvinyl imidazoline can be easily converted to a salt by contact with an acid. Specifically, the water-soluble polyvinyl imidazoline can be converted into a polyvinyl imidazoline chloride by adding an equivalent amount of a hydrochloric acid aqueous solution.

In the method of the present invention, the polyvinyl imidazoline as a reaction product may be purified as it is or may be purified in the form of a salt.

[0023]

The present invention provides a process for producing polyvinylimidazoline which does not produce hydrogen sulfide as a by-product and which does not thermally decompose a polymer of acrylonitrile (or methacrylonitrile). is there.

[0024]

EXAMPLES Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited thereto.

Example 1 25 g of polyacrylonitrile (average molecular weight 86,000),
Ethylenediamine (60 g) and zinc acetate (3 g) were placed in a 200 ml electromagnetically stirred stainless steel autoclave, purged with nitrogen, and then heated. When the temperature exceeded 100 ° C., the pressure increased, and reached 0.1 MPa at 130 ° C. The temperature was raised as it was to 180 ° C. The pressure in the autoclave continued to rise and reached 1.9 MPa after 5 hours.

This was cooled and a viscous red solution was taken out. This was poured into acetone to give a pale yellow solid. When this was dried, 49 g of a pale yellow polyvinyl imidazoline powder was obtained.

Example 2 A 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 zinc chloride was used instead of zinc acetate.
In 5 hours after reaching 180 ° C., the pressure of 1.8 MPa increased.

This was cooled and poured into acetone to give a pale yellow solid. When this was dried, 45 g of a pale yellow polyvinyl imidazoline powder was obtained.

Example 3 26 g of polyacrylonitrile (average molecular weight 86,000),
Ethylenediamine (60 g) and copper acetate (3 g) were placed in a 200 ml electromagnetically stirred stainless steel autoclave, purged with nitrogen, and then heated to 220 ° C. 2.5 MPa at 220 ° C
Became. After 30 minutes, it was cooled, the viscous brown solution was taken out, poured into acetone and dried to give 46 g.
A brown solid was obtained.

Example 4 50 g of an acrylonitrile / styrene copolymer (acrylonitrile 25%), 60 g of ethylenediamine, and 3 g of zinc acetate were placed in a 200 ml electromagnetically stirred stainless steel autoclave. 5
The pressure after time became 1.0 MPa.

After cooling, a viscous white solution was taken out and poured into water to give a white solid. When this was dried, 53 g of a white vinylimidazoline styrene copolymer powder was obtained.

Claims (6)

[Claims] 1. A method for producing polyvinyl imidazoline or a salt thereof, comprising reacting a polymer containing a nitrile group with a polyamine, wherein the reaction is carried out in the presence of a metal salt. 2. The method according to claim 1, wherein the polymer containing a nitrile group is a homopolymer or a copolymer of acrylonitrile or methacrylonitrile. 3. The method according to claim 1, 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 represent a hydrogen, an aliphatic, an araliphatic or an aromatic group) 4. The method according to claim 1, wherein the metal salt is an organic acid salt or an inorganic acid salt of zinc, iron, copper, cobalt, manganese, aluminum, tin, mercury, chromium or cadmium. 3. The method according to any one of 3. 5. The method according to claim 1, wherein the reaction temperature is in the range of 100 to 300 ° C. 6. The method according to claim 1, wherein the reaction is carried out in a liquid phase.