JPH0314803A - Sulfonation of aromatic polymer - Google Patents

Abstract

PURPOSE:To enable a high-molecular aromatic polymer to be sulfonated and facilitate washing by separately feeding an aromatic polymer solution and a sulfonating agent to a venturi mixer for sulfonation. CONSTITUTION:An aromatic polymer solution and a sulfonating agent are separately fed to a venturi mixer to conduct sulfonation by mixing both members. Examples of the solvent for the polymer include those inert to the sulfonating agent, such as 1-2C aliphatic halogenated hydrocarbons and 1-3C nitrated hydrocarbons. A preferably sulfonating agent is anhydrous sulfuric acid. The venturi mixer to be used is a tube having constricted middle section and provided with a liquid feed port at that section. The polymer solution or the sulfonating agent flows at a higher velocity in the constricted section through the feed port to be dispersed in fine droplets and at the same time cause vigorous turbulent flow for mixing.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for sulfonating aromatic polymers.

[Prior Art] A method for sulfonating polystyrene in which a polystyrene solution and a sulfonating agent are continuously supplied separately at a rate that satisfies specific conditions to a sulfonation reactor equipped with a high shear force stirrer. is known (for example, Japanese Patent Application Laid-Open No. 83-17
270.3).

[Problems to be Solved by the Invention] However, as the average molecular weight of polystyrene used as a raw material increases, the viscosity of the reaction liquid increases.

As a result, there is a problem that handling becomes difficult and the yield of water-soluble sulfonated polystyrene is extremely reduced. Furthermore, since the stirrer has a complicated structure, there is also the problem that cleaning is difficult.

[Means for Solving the Problems] The present inventor has arrived at the present invention as a result of intensive study on a method for sulfonating aromatic polymers such as high molecular weight polystyrene that is easy to clean. .

That is, the present invention provides a sulfonated aromatic polymer characterized in that when mixing an aromatic polymer and a sulfonating agent for sulfonation, the aromatic polymer solution and the sulfonating agent are separately supplied to a Venturi type mixer. It is a method of conversion.

The aromatic polymer in the present invention may be any polymer having an aromatic nucleus in its main chain or side chain, and examples thereof include vinyl aromatic polymers, aromatic polyethers, aromatic polyesters, and the like.

Examples of the vinyl aromatic polymer include styrene polymers or copolymers, α-methylstyrene polymers or copolymers, and the like. Examples of the styrene copolymer or α-methylstyrene copolymer include styrene or α-methylstyrene copolymer.
Methylstyrene and alkyl (meth)acrylates [methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, stearyl (meth)acrylate, etc.], Fatty acid vinyl [vinyl acetate, vinyl propionate, etc.], aromatic hydrocarbon monomers [vinylnaphthalene, vinyltoluene, p-methylstyrene, etc.], unsaturated carboxylic acids or their anhydrides [(meth)acrylic acid, maleic anhydride acids, itaconic anhydride, etc.], (chlorinated) olefins [alpha-olefins, isoprene, isobutylene, diisobutylene, butadiene, biperylene, chloroprene, etc., monomers containing nitrile groups [(meth)
Examples include copolymers with acrylonitrile and the like.

Examples of the aromatic polyether include poly(2, dimethylphenylene ether).

Examples of the aromatic polyester include polyethylene terephthalate, polyethylene isophthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polycyclohexylene dimethylene terephthalate, polyethylene-2, and tonaphthalate. The aromatic nucleus content in the aromatic polymer is usually at least 10%, preferably at least 20%, based on the weight of the polymer. For example, in the case of a styrene copolymer, the styrene monomer unit content m in the styrene copolymer is usually 15% or more, based on the weight of the copolymer.
Preferably it is 30% or more. In the case of aromatic polyesters, the aromatic nucleus content in the aromatic polyester is usually 10% or more, preferably 20%, based on the weight of the polymer.
% or more.

The molecular weight of the aromatic polymer is usually t,ooo to 20,0
0000, preferably 2,0(to ~1,000
, (1 (to). In the case of styrene polymers or styrene copolymers, the molecular weight is usually 1,000 to 2,
000.000, preferably 2,GoO~t,oo
o, ooo. For aromatic polyethers, the molecular weight is usually t,ooo #t,ooo,ooo
1 Preferably 2,000 to 500,000. In the case of aromatic polyesters, the molecular weight is usually 1
,000 to 1,000,0001 preferably 2,0
00 to 500,000.

In the present invention, the aromatic polymer is sulfonated in solution. As a solvent for making a solution, the number of carbon atoms is usually 1 to 1.
Examples include those that are inert to the sulfonating agent, such as aliphatic halogenated hydrocarbons of 2 and nitrated hydrocarbons usually having 1 to 3 carbon atoms. As aliphatic halogenated hydrocarbons, 1,2
-dichloroethane, methylene dichloride, ethyl chloride,
Carbon tetrachloride,! , 1-dichloroethane, 1,1,2.2
-Tetrachloroethane, chloroform, ethylene dibromide and the like. Examples of nitrated aliphatic hydrocarbons include nitromethane, nitroethane, 1-nitropropane,
Examples include 2-nitropropane. Preferred solvents are halogenated hydrocarbons.

Dissolution of the aromatic polymer depends on the molecular weight of the polymer, but usually 1 to 100 parts by weight of the aromatic polymer is dissolved per 100 parts by weight of the solvent.
Sulfuric anhydride is preferably used as the sulfonating agent in which 100 parts by weight, preferably 5 to 50 parts by weight, is dissolved. Liquid sulfuric anhydride, liquid sulfuric anhydride with nitrogen ● inert gas such as dry air and! Sulfuric anhydride diluted with an inert solvent such as aliphatic halogenated hydrocarbons having 1 to 2 carbon atoms such as , 2-dichloroethane, and ethyl chloride can also be used. The concentration of sulfuric anhydride diluted with an inert gas is usually 1-15% by volume, preferably 3-5% by volume. The concentration of sulfuric anhydride diluted with an inert solvent is normal! -50% by weight, preferably 5-20% by weight. Moreover, a complex of sulfuric anhydride and Lewis base can also be used, which is preferable. Lewis bases include trialkyl phosphates [triethyl phosphate, trimethyl phosphate, etc.], fatty acid alkyl esters [ethyl acetate, ethyl palmitate, etc.]
, ether or thioether [dioxane, thioxane, diethyl ether, etc.]. Preferred Lewis bases are trialkyl phosphates and fatty acid alkyl esters.

In the present invention, the amount of the sulfonating agent used is usually 0.4 to 2 mol, preferably 0.5 to 1.5 mol, per 1 mol of aromatic nucleus units in the aromatic polymer. be.

If the amount of the sulfonating agent is less than 0.4 mol, the dispersibility of the sulfonated reaction product in water will be poor. As the amount of sulfonating agent increases, by-products such as sulfur sulfate increase.

When using a complex of sulfuric anhydride and a Lewis base, the amount of Lewis base used is usually 0.01-1 mole of aromatic nuclear units constituting the total aromatic polymer used in the reaction.
1 molar amount, preferably 0.02 to 0.5 molar amount.

The cherry-type mixer used in the present invention is a mixer in which a tube is squeezed in the middle, and a liquid inlet is provided in the squeezed portion. Polymer solution (or sulfonating agent) at the crest of the tube
The sulfonating agent (or polymer solution) is introduced as a high-speed fluid through the inlet of the constriction part, dispersed into fine droplets, and mixed by creating a state of intense turbulence. The tube is usually a cylindrical straight tube. In order to clarify the invention, the invention will be explained with reference to the drawings. FIG. 2 shows a sectional view of a mixer used in the present invention. Polymer solution (or sulfonating agent)
The polymer solution (or sulfonating agent) introduced from the inlet 1 enters the throttle section 3, where the sulfonating agent (or polymer solution) is added from the sulfonating agent (or polymer solution) inlet.

The linear velocity v1 of the fluid at the throttle [3 is usually 100 to 3,000 cm/sea in the case of liquid and 10#100cm/sea in the case of gas. If the linear velocity Vl is less than 100 cm/SeC in the case of a liquid or less than 10 m/sea in the case of a gas, mixing is insufficient and the amount of water-insoluble sulfonated polymer increases, resulting in an extreme yield of water-soluble sulfonated polymer. decreases to

The diameter from the polymer solution (or sulfonating agent) inlet 1 to the constriction section 3 is usually 10 to 50 mm, and the diameter of the constriction section is usually 1 to 5 mm. The length of the constriction part is the inlet port 4.
It is sufficient if the inner diameter of

Raw materials such as an aromatic polymer solution and a sulfonating agent are supplied to the Venturi mixer 5 by conventional means, such as a raw material placed in a sulfonating agent (or polymer solution) tank 8 or a polymer solution (or sulfonating agent) tank 9. This can be carried out using a pump such as a plunger pump or an injection pump 10, 11 such as a turbo blower.

The polymer solution and sulfonating agent mixed in the Venturi type mixer 5 are usually stored in a large capacity storage tank 6 to complete the sulfonation reaction.

The reaction temperature for sulfonation is usually 0 to 80°C, preferably 10 to 50°C. The reaction is carried out under anhydrous conditions.

The resulting sulfonation reaction products are usually hydroxides, carbonates, or ammonia of alkali metals such as sodium and potassium, alkaline earth metals such as calcium and magnesium, amines such as triethylamine, dimethylamine, laurylamine, It is neutralized and converted into a salt using a neutralizing agent such as an alkylamine such as stearinoleamine or an alkanolamine such as ethanolamine. The solvent is removed by conventional methods such as separation, filtration, and distillation to obtain a water-soluble liquid or powdered sulfonated aromatic polymer.

[Examples] Hereinafter, the present invention will be further explained with reference to Examples, but the present invention is not limited thereto.

Examples 1 to 4 Polystyrene having an average molecular weight of 10,000 or 200,000 was dissolved in 1,2-dichloroethane as a solvent to prepare a 15% by weight polymer solution. Further, as a sulfonating agent, 10% by weight liquid sulfuric anhydride diluted with 1,2-dichloroethane was used. As shown in Table 1, the polymer solution and diluted sulfuric anhydride were separately supplied to the penturi mixer 5 and mixed under the conditions of the fluid linear velocity Vl of the constriction section 3. The polymer solution was introduced through the inlet ltP, and the diluted sulfuric anhydride was introduced through the inlet 4. In addition, the penturi mixer 5 has an inner diameter of 20 mm from the inlet 1 to the throttle part 3.
Inner diameter of constriction part 3 1. The one shown in Figure 2 of sm m was used.

The mixed solution was immediately stored in a storage tank and the sulfonation reaction was completed at a temperature of 20°C. Next, the sulfonation reaction solution was taken out from the storage tank, dissolved in water, and neutralized by adding 30% NaOH aqueous solution. Furthermore, 1,2-dichloroethane was separated by distillation to obtain sodium polystyrene sulfonate. The results are summarized in Table-1. In addition, in the table, the yield of water-soluble sodium polystyrene sulfonate was determined from Table-1. The sulfonation rate is the rate of introduction of sulfonic acid groups per styrene monomer unit in polystyrene.

Comparative Examples 1 to 4 As comparative examples, the polymer solution and the sulfonating agent were separately supplied to the benchmark mixer and the linear velocity Vl of the throttle port was changed in the same manner as in Examples 1 to 4. The results are shown in Table-2.

Table 2 According to the present invention, by adopting simple means, not only aromatic polymers such as low molecular weight polystyrene but also high molecular weight aromatic polymers can be sulfonated, resulting in a high sulfonation rate. Sulfonated polymers can be produced in high yield.

Furthermore, the method of the present invention allows for easy cleaning of the mixer and is extremely excellent as an industrial process.

Because of the above effects, the sulfonated aromatic polymer obtained in the present invention is useful for applications such as antistatic agents for paper or resins, dispersants for inorganic and organic pigments, and water reducing agents for concrete.

[Brief explanation of the drawing]

FIG. 1 is a flow sheet, and FIG. 2 is a sectional view of a venturi mixer. 1: Polymer solution (or sulfonating agent) inlet, 2: Mixture outlet, 3: Squeezing section, 4: Sulfonating agent (or polymer solution) inlet, 5: Bencherry type mixer, 6: Storage tank, 7: Valve , 8: Sulfonating agent (polymer solution) tank, 9: Polymer solution (sulfonating agent) tank, 1011N injection pump drawing engraving Figure 1 Figure 2 Manual correction (method) 1. Incident display address: 11-1 Hitotsubashinohonmachi, Higashiyama-ku, Kyoto City Name (22B) Sanyo Chemical Industries, Ltd. Representative Takehiko Fujimoto 4. Date of amendment order: March 2G, 1999 (shipment date) 5. Number of inventions to be increased due to amendment O. Send drawings with drawing numbers as shown in the attached sheet.

Claims (1)

[Claims] 1. A method for sulfonating an aromatic polymer, which comprises feeding the aromatic polymer solution and the sulfonating agent separately to a Venturi mixer when mixing the aromatic polymer and the sulfonating agent for sulfonation.