JPH0457684B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel water-soluble polymer and its use as a flocculant or drainage/retention aid. Water-soluble polymers include flocculants, drainage and retention aids,
Widely used for other purposes. these are,
Generally, it has a molecular weight of several hundred thousand to tens of millions, and is in the form of powder, paste, or water-in-oil (W/O).
type) as an emulsion. Powdered polymers are difficult to melt and require significant investment in melting equipment. In addition, fine powder dust is generated, which is unfavorable in terms of the working environment. Further, since paste-like products have high viscosity and are difficult to provide in high concentrations, they are not only economically disadvantageous, but also generally have poor product stability. Water-in-oil emulsions have advantages over the former two, such as rapid dispersion and dissolution in water, and simple dissolution equipment, but because they use relatively large amounts of organic solvents,
Not only is it difficult to handle, but it is also economically disadvantageous. Furthermore, when used as a coagulant, problems may arise in the treatment of organic solvents. In addition, the stability of the product is generally not good, such as separation of two layers and creaming during long-term storage. The present inventor has recently endeavored to search for cationic polymers, which are in particular demand in the field of use of water-soluble polymers such as flocculants, and found that they are economically advantageous, easy to handle, and have good product stability. The present invention was achieved by finding a method for producing a good cationic polymer. That is, the present invention is based on the general formula After emulsion polymerization of the monomer represented by () or a mixture of this and other copolymerizable vinyl monomers in water with a monomer composition that yields a water-insoluble polymer, an acid or salt containing 10 obtained by dissolving in water
a water-soluble polymer having a molecular weight of 10,000 to 30,000,000
and a method for using it as a flocculant, drainage/retention aid. The present invention will be explained in more detail below. Examples of monomers represented by the general formula () that are essential components of the water-soluble polymer of the present invention include diethylaminoethyl acrylate, diethylaminoethyl methacrylate, dipropylaminoethyl acrylate, dipropylaminoethyl methacrylate, and dibutyl Examples include aminoethyl methacrylate, diethylaminopropyl methacrylamide, dipropylaminopropyl methacrylamide, dipropylaminopropylacrylamide, dibutylaminopropyl methacrylamide, diptylaminopropylacrylamide, and the like. As the other vinyl monomer () that can be copolymerized with the monomer (), one or more hydrophobic monomers selected from acrylic ester, methacryl ester, acrylonitrile, and styrene are used. It will be done. The proportion of the monomer () to be used is selected within a range such that the resulting polymer is soluble in water containing the acid or salt. For example, in a copolymer of diethylaminoethyl methacrylate and mesyl methacrylate, a water-soluble polymer is obtained in which methyl methacrylate is present in a range of 0 to 30% by weight based on the total monomers. Surfactants used during emulsion polymerization include:
Usual surfactants such as anionic, nonionic, and cationic surfactants can be used, such as sodium alkylbenzene sulfonate, alkyl sulfate, sodium alkyl sulfonate, polyoxyethylene alkyl ether sulfate, and polyoxyethylene alkyl phenyl ether. Examples include sulfates, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, alkyl amines, and betaine types. Generally, a combination of anionic and nonionic surfactants provides a more stable emulsion polymerization pair with less coagulation. As the polymerization catalyst used, common radical polymerization initiators such as peroxides and azo compounds are used, but water-soluble polymerization initiators are particularly preferred. Examples of water-soluble polymerization initiators include peroxides such as ammonium persulfate, potassium persulfate, peracetic acid, hydrogen peroxide, and 2,2'-azobis-2-aminodinopropane hydrochloride, 4,4'-azobis Examples include azo compounds such as -4-cyanopentanoid acid. When a peroxide is used as an initiator, it can be used as a redox-based initiator in the presence of a suitable reducing agent, if necessary. The obtained polymer has a molecular weight of 100,000 to 3,000,000, and various grades can be prepared depending on the purpose. The present inventors have discovered that the emulsion thus obtained is water-insoluble as it is, but becomes water-soluble in water containing an inorganic or organic acid or a salt thereof. As a method for dissolving the emulsion, the emulsion may be added to water to which an acid has been added in advance, or conversely, an acid may be added to an emulsion obtained by adding the emulsion to water. Preferred acids include hydrochloric acid, sulfuric acid, nitric acid, acetic acid, formic acid, maleic acid, fumaric acid, citric acid, tartaric acid, adipic acid, sulfamic acid, and toluenesulfonic acid. Preferred salts include aluminum sulfate,
There are salts of strong acids and weak bases such as aluminum chloride and ferric chloride. The amount of acid or salt used must be such that the polymer becomes water-soluble, and is generally at least equivalent to the amount of the cationic monomer. The emulsion may be dissolved before the resulting water-soluble polymer is used for various purposes. One aspect of the product is that it is preferable to store it in an emulsion state and to make it water-soluble before use because it is easier to dissolve than powdered products and the stability of the polymer in an emulsion state is good. It is. The first use of the resulting water-soluble polymer is as a flocculant. Conventionally, most commercially available flocculants are powder type or paste type, and water-in-oil (W/O) emulsions have also been proposed. However, as mentioned above, these had drawbacks in solubility, handling, etc. However, the flocculant using the water-soluble polymer of the present invention uses an oil-in-water (O/W) emulsion. Since it is manufactured, it is easy to adjust the water solubility, and unlike powder type, special dissolving equipment is not required for dissolution. Generally, in the case of cationic flocculants, the performance may vary depending on the salt type, but the O/W of the present invention
When dissolving the emulsion, it is possible to change the salt type to some extent depending on the type of suspended water such as waste water. When used as a flocculant, the amount of water-soluble polymer used varies depending on the type of wastewater or water to be treated;
In general, for suspended solids (ss), in terms of solid content
It is about 0.05 to 2%. The polymer of the present invention is also effective as a drainage and retention aid in the paper industry. When used as a drainage/retention improver, it is usually dissolved in a concentration of 0.1 to 0.5% by weight. The amount added varies considerably depending on the raw material, machine characteristics, and purpose, but it is used in the range of 0.005 to 0.5% (in terms of solid content) based on the pulp. When the polymer of the present invention is used, the retention of fine fibers and fillers is improved, and the retention of sizing agents and paper strength agents is also improved. In addition, the freeness is improved, making it possible to increase the papermaking speed, reducing the web moisture content, and greatly reducing the amount of steam consumed. In addition to various organic and inorganic acids, aluminum sulfate, which is commonly used in papermaking systems, can be used as the acid or salt used to water-solubilize the emulsion when used as a drainage/retention aid, from the point of view of workability. In addition, it prevents the accumulation of anions such as sulfate ions in white water, prevents corrosion of the machine due to a decrease in pH, a decrease in paper strength, and a decrease in size. savings,
There are benefits such as a reduction in the burden of wastewater treatment. As detailed above, the polymer of the present invention is easy to produce and has many industrially useful uses such as a flocculant, drainage/retention aid, and the like. The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto.
In addition, % in the examples is weight % unless otherwise specified.
shows. Example 1 In a 14-necked flask equipped with a stirring bar, cooling tube, nitrogen introduction tube, and thermometer, 180 g of diethylaminoethyl methacrylate, 120 g of deionized water, and 1% (based on monomer) Emar 10 (Kao Soap Co., Ltd.) were added. ) Emulgen 930 (Kao Soap Co., Ltd.) 2% (based on monomers) was charged, and after deoxidizing by passing nitrogen gas under stirring, the contents of the flask were kept at 15°C. Next, ammonium persulfate 0.36g and sodium bisulfite
0.09 g was added and polymerization was carried out at 15 to 20° C. for 4 hours to obtain a milky white O/W type emulsion (A) of a cationic polymer. After diluting the resulting emulsion to a polymer concentration of 2%, various inorganic and organic acids and salts were added in equivalent amounts to the weight of the emulsion, which easily dissolved and resulted in a colorless and transparent polymer with a molecular weight of 3 million. An aqueous solution could be obtained. The results are shown in Table 1. Example 2 In the method of Example 1, deoxidation was carried out in the same manner, and then the contents of the flask were kept at 50°C and 2.
2'-azobis-2-aminodinopropane hydrochloride
1.08g was added and polymerized at 50 to 55°C for 5 hours to obtain an O/W type emulsion (B) of a cationic polymer. The polymer concentration of the obtained emulsion is 2
After diluting the polymer with tap water so that the polymer had a molecular weight of 830,000 %, various inorganic and organic acids and salts were added in equivalent amounts to the polymer. The results are shown in Table 1. Example 3 In Example 1, the monomers were a mixture of diethylaminoethim methacrylate/methyl methacrylate (90/10 and 70/30) shown in Table 2.
(%)) Emulsions (C) and (D) were obtained by the method of Example 1. The molecular weights were 1,740,000 and 260,000, respectively. Table 2 shows the results of a dissolution test conducted in the same manner as in Example 1. Example 4 The emulsion obtained in Examples 1 to 3 was used as a flocculant. 500 ml of sewage treatment plant digested sludge with a suspension concentration of 2.5% was taken into a beaker and treated with the acids shown in Table 3 to dissolve it while stirring at 150 rpm.
0.2% polymer aqueous solution 0.2~0.3% based on solid content
and stirred for 1 minute. After observing the state of the formed flocs, a dehydration test was conducted using an experimental centrifugal dehydration tester to measure the moisture content of the cake. The results are shown in Table 3.

【table】

【table】

【table】

[Table] Acrylate
MMA: Methyl methacrylate

[Table] Example 5 The emulsion obtained in Example 1 was
After diluting with tap water to 0.2%, 2N−
An equivalent amount of HCl was added to the polymer to obtain a 0.2% aqueous polymer solution. Dilute beaten LBKP in 400 ml Canadian Standard Freeness (CSF) to a 1% concentration. The resulting pulp slurry contains 0.3% pulp for rosin size, 3% pulp for sulfate band, 0.3% pulp for anionic paper strength enhancement, 20% pulp for talc,
0.005 to 0.002% (based on pulp, solid content) of the above-mentioned 0.2% polymer aqueous solution was added and paper was made using a TAPPI hand paper machine. The yield of talc was measured by measuring the talc content in the obtained sheet. The results are shown in Table 4. Example 6 Using the 0.2% aqueous polymer solution obtained in Example 5,
It was evaluated as a water leak improver. Waste cardboard beaten in 350 ml CSF (Canadian Freeness) was diluted to 1% using industrial water. To the obtained pulp slurry, 0.3% of rosin sizing agent to pulp, 3% of sulfuric acid band to pulp, and 0.5% of anionic paper strength agent to pulp are respectively added with stirring. Finally, after adding the above-mentioned aqueous polymer solution to the pulp at 0.02 to 0.1% (in terms of solid content),
Freeness was measured by the TAPPI standard method. The results are shown in Table 5.

【table】

【table】

[Claims]

1 (A) A solid catalyst component in which a porous carrier having a pore radius of 75 to 5000 Å and a pore volume of 0.25 cc/g or more is impregnated with a catalyst component consisting of at least titanium, magnesium, and chlorine, and (B) Using a catalyst system containing at least an organoaluminum compound, ethylene is slurry polymerized in a propane and/or butane solvent in a first step, or ethylene is polymerized in a gas phase, and then ethylene is polymerized in a gas phase in a second step. Random copolymerization of and α-olefin,
The ethylene content in the copolymer produced in this process is 15
~90 mol%, tetralin has an intrinsic viscosity of 0.3 to 10 at 135°C, and is polymerized so that the copolymer produced in the step is 60 to 97% by weight based on the total polymer amount. A method for producing a granular thermoplastic elastomer.

Claims (1)

(However, in the formula, R ₁ is H or CH ₃ , R ₂ , R ₃
is an alkyl group represented by CnH ₂ n+l, n is a positive integer, and A is -O-CH ₂ - or -NH-
It represents _CH2 - _CH2- , and _R1 , _R2 , and _R3 are selected within a range in which the monomer is poorly soluble or insoluble in water. ), or one or two monomers selected from acrylic esters, methacrylic esters, acrylonitrile, and styrene.
A mixture of 30% by weight or less of vinyl monomer based on the total monomers is emulsion polymerized in water with a monomer composition that yields a water-insoluble polymer, and then immersed in water containing acid or salt. A method in which a water-soluble polymer with a molecular weight of 100,000 to 30 million obtained by dissolution is used as a flocculant. 3 General formula (However, in the formula, R ₁ is H or CH ₃ , R ₂ , R ₃
is an alkyl group represented by CnH ₂ n+l, n is a positive integer, and A is -O-CH ₂ - or -NH-
It represents _CH2 - _CH2- , and _R1 , _R2 , and _R3 are selected within a range in which the monomer is poorly soluble or insoluble in water. ), or one or two monomers selected from acrylic esters, methacrylic esters, acrylonitrile, and styrene.
A mixture of 30% by weight or less of vinyl monomer based on the total monomers is emulsion polymerized in water with a monomer composition that yields a water-insoluble polymer, and then immersed in water containing acid or salt. A method in which a water-soluble polymer with a molecular weight of 100,000 to 30 million obtained by dissolving is used as a drainage and retention aid.