JPS6221007B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a modified starch that has high viscosity dilution resistance and can be used as a thickener and a polymer flocculant. Conventionally, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, guar gum, etc. have been known as high viscosity thickeners, but they do not have sufficient viscosity dilution resistance, especially at an aqueous solution concentration of 1% or less, and they do not have sufficient resistance to dilution when dissolved. It was not enough to make mamako or to dissolve it after dispersing it in hot water. In addition, cationic modified products of high molecular weight polyacrylamide are known as cationic polymer flocculants, but this requires a complicated drying process and is often supplied in the form of a solution.
It is extremely inconvenient in terms of dilution during use and transportation.
In recent years, starch graft copolymerized with cationic monomers has been proposed, but to date these products have not been provided with sufficient flocculating action. The present inventors conducted intensive research to solve these drawbacks, and as a result, we found that graft-modified starch, in which quaternary ammonium-modified cationic substituents are introduced into both the graft side chain and the backbone polymer, has excellent physical properties for these purposes. The present invention was completed based on these findings. That is, a quaternary ammonium modified cation etherified starch with a degree of substitution of 0.001 to 0.5 is graft copolymerized with an essential monomer containing a quaternary ammonium base, or a hydroxyl group, an alkyl ester carboxylate group, a glycidyl group, or a halogen-containing alkyl group is added to the starch. After graft copolymerizing one or more monomers selected from monomers containing groups etc. as essential monomers, one or two selected from halogenated alkyl quaternary ammonium salts, tertiary amines, quaternized amino alcohols, etc. It is produced by introducing a quaternary ammonium-modified cationic substituent into the starch portion and graft side chain of the backbone polymer using one or more cationizing agents. Furthermore, the present invention also includes introducing a tertiary amine and then quaternizing it in the same manner as the method of introducing quaternary ammonium. Quaternary ammonium-modified cation etherified starches include halogenated alkyl quaternary ammonium salts such as 3-chloro-2-hydroxypropyltrimethylammonium chloride, 3-chloro-2-hydroxypropyltriethylammonium chloride, and 2-chloroethyltrimethylammonium chloride. Examples include cationic etherification agents. As the quaternary ammonium base-containing monomer,
N such as N・N・N-trimethyl-N-acryloyloxyethylammonium chloride, N・N・N-triethyl-N-acryloyloxyethylammonium chloride, 2-hydroxy-3-acryloyloxypropyltrimethylammonium chloride, etc.・N・N-trialkyl-N-acryloyloxyalkyl ammonium salt, N・N・N
-N/N/N- such as trimethyl-N-methacryloyloxyalkylammonium chloride, N/N/N-triethyl-N-methacryloyloxyalkylammonium chloride, 2-hydroxy-3-methacryloyloxypropyltrimethylammonium chloride, etc. Trialkyl-N-methacryloyloxyalkyl ammonium salts are mentioned. Monoethylenically unsaturated alcohols such as (meth)allyl alcohol, monoethylenically unsaturated esters or ethers of polyols (alkylene glycols, glycerin, polyoxyalkylene glycols, etc.) such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)
Acrylate, triethylene glycol (meth)
Hydroxyl group-containing monomers such as acrylate, poly-oxyethylene-oxypropylene (random or block) glycol mono(meth)allyl ether are graft copolymerized to starch, or vinyl acetate etc. are graft copolymerized and then hydrolyzed to form hydroxyl groups. The graft side chain contained in the base polymer is made to act on the hydroxyl group after graft modification with the halogenated alkyl quaternary ammonium salt, which is similar to the agent for etherifying the hydroxyl group of starch, which is the backbone polymer, to convert the quaternary ammonium salt into the graft side chain or the graft side. Introducing starch, which is the chain and backbone polymer. Examples of alkyl ester carboxylate-containing monomers include acrylic acid alkyl esters such as methyl acrylate and ethyl acrylate, and methacrylic acid alkyl esters such as methyl methacrylate and ethyl methacrylate. Examples include trialkylaminoalkyl salt alcohols such as trimethylaminoethyl chloride alcohol, and after graft modification by transesterification with the carboxyalkyl ester, a quaternary ammonium base is introduced. Examples of glycidyl group-containing monomers include glycidyl acrylate, glycidyl methacrylate, glycidyl allyl ether, glycidyl vinyl ether, etc. After grafting these monomers onto starch, tertiary alkyl amines such as trimethylamine and triethylamine are added. A quaternary ammonium base is introduced into the graft side chain by acting on the glycidyl group. Examples of monomers having a halogen-containing alkyl group include halogenated alkyl acrylates and methacrylates such as 3-chloro-2-hydroxypropyl acrylate, and unsaturated halogenated alkyl ethylene monomers such as vinyl chloride and allyl chloride. After graft polymerizing these monomers onto starch, a quaternary ammonium base is introduced into the graft side chain by reacting with a trialkylamine such as trimethylamine or triethylamine. The starch used as a raw material in the present invention is
Natural starches such as potato starch, sweet potato starch, corn starch, waxy corn starch, high amylose corn starch, wheat starch, rice starch, tapioca starch, sago starch and their decomposition products, amylose and amylopectin fractions, cross-linked starches, ethers Examples include modified starch, oxidized starch, esterified starch, acid-treated starch, graft-modified starch, enzyme-treated starch, modified starch such as dextrin, and starch-containing substances such as wheat flour, corn flour, dried sweet potato, and dried tapioca. The graft polymerization reaction between these raw material starches and monomers is carried out using an organic solvent such as methanol or acetone, water, or a mixed solution of these as a solvent.
Using a common graft polymerization initiator such as ceric salt, persulfate, persulfate-sulfite, hydrogen peroxide-Mohr's salt, etc., 0-95℃, preferably 10-60℃.
This can be done in accordance with conventional methods. The graft-modified starch used in the present invention has a graft side chain that is attached to the graft side chain before or after graft polymerization according to a conventional method.
Alternatively, at the same time as graft polymerization, other copolymerizable monomers such as hydroxyl group-containing monomers, monoethylenically unsaturated alcohols such as allyl alcohol, monoethylenically unsaturated esters of polyols (alkylene glycol, glycerin, polyoxyalkylene glycol, etc.) or ethers such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, triethylene glycol (meth)acrylate, poly-
Oxyethylene-oxypropylene (random or blocked) glycol mono(meth)allyl ether (terminal hydroxyl group may be etherified or esterified). Amide group-containing monomer:
(meth)acrylamide, N-alkyl (meth)
Acrylamide e.g. N-methylacrylamide, N-hexylacrylamide, N.N-dialkyl(meth)acrylamide e.g. N.N-
Dimethylacrylamide, N.N-di-n- or i-propylacrylamide, N-hydroxyalkyl (meth)acrylamide, e.g.
Methylol (meth)acrylamide, N-hydroxyethyl (meth)acrylamide. Amino group-containing monomer: monoethylenically unsaturated monomer or amino group-containing ester of dicarboxylic acid (dialkylaminoalkyl ester, dihydroxyalkylaminoalkyl ester, morpholinoalkyl ester, etc.) such as dimethylaminoethyl (meth)acrylate, diethylaminoethyl ( meth)acrylate, morpholinoethyl(meth)acrylate, dimethylaminoethyl fumarate.
Heterocyclic vinyl compounds, such as vinylpyridines (2-vinylpyridine, 4-vinylpyridine,
N-vinylpyridine), N-vinylimidazole, and other water-soluble monomers; vinyl acetate, acrylonitrile, acrylic acid alkyl esters, methacrylic acid alkyl esters, styrene, vinyl chloride, and other nonionic water-insoluble monomers; In the present invention, which requires thickening properties and higher water solubility, water-soluble monomers are preferred, and water-soluble monomers such as hydroxy (meth)acrylate, hydroxypropyl (meth)acrylate, and triethylene glycol (meth)acrylate are preferred. Copolymerizing (meth)acrylate or the like is preferable because it improves the grafting efficiency of the quaternary ammonium salt-containing monomer, which has poor grafting efficiency. Before or after graft polymerization of starch, which is a backbone polymer, a cationized etherification agent such as the above-mentioned halogenated quaternary ammonium salt is used to increase the degree of etherification,
0.001 to 0.5 and modified so that the nitrogen content of the graft side chain in the graft side chain having a quaternary ammonium salt is 0.01 to 3.0 parts based on 100 parts of the main polymer. A graft-modified starch having a target thickening property, that is, a Bruckfield viscosity of 1% aqueous solution at 20° C. of 1000 centipoise or more, has a quaternary ammonium salt in both the backbone polymer and the graft side chain. The thickener using the high-viscosity graft-modified starch obtained by the present invention essentially contains a strong base type quaternary ammonium salt, exhibits thickening properties in a wide pH range from acidity to weak alkalinity, and has bactericidal, preservative, and antiseptic properties. It has excellent adhesion, suspension action, emulsification action, oil resistance, organic solvent resistance, and adsorption to anionic substances such as cellulose and fibers. Binders, thickeners for ceramics and plaster, ice glazes, pesticides, seed spreading agents, protective coatings for seeds and bulbs, papermaking, latex thickeners, protective colloids for paints and synthetic resins, antistatic. It is used as a thickener for agents, soil conditioners, printing pastes, fire extinguishers, etc. When drilling wells such as oil wells, in order to take out the drilling debris to the ground, muddy water is sent into the excavation area through the center of the drill pipe, and is circulated from the outside of the pipe to the ground together with the drilling debris.
By adding 0.1 to 1.0% of the graft-modified starch of the present invention to this muddy water, the amount of muddy water can be reduced by 15 to 30% compared to the case where it is not added. For cosmetics, when the graft-modified starch of the present invention is used in hair products such as hair styling products and shampoos, the graft-modified starch adsorbs to the hair and partially remains even after hair washing, making it easy to set the hair. Because it has a strong affinity with hair, the film does not become dandruff-like and peel off. It can also be used as a thickener for various creams. When the graft-modified starch of the present invention is used as a thickening adhesive for fiber walls, the adhesive strength between the wall surface and the coating material is great, and workability such as troweling is good, resulting in flopping after coating. You can obtain glue that is not used. Conventionally, starch that has not been chemically treated has been used as a binder for compound feed for fish farming, but its thickening effect and cohesive power are weak, so a large amount of starch must be mixed, which can disrupt the nutritional balance. It was not a good thing. When the graft-modified starch of the present invention is used, it exhibits a caking effect in a much smaller amount than conventional starches and is less susceptible to spoilage, thereby preventing deterioration of water quality. The graft-modified starch of the present invention has excellent bactericidal properties and thickening properties, so when preserving fish etc. in a frozen state, by using the graft-modified starch paste of the present invention, excellent viscosity can be achieved just by immersing it in the paste. A thicker layer of ice forms, increasing the strength of the ice layer and extending its shelf life. The polymer flocculant using the graft-modified starch of the present invention is extremely effective in treating domestic wastewater such as sewage and human waste treatment, and all conventional commercially available cationic flocculants are supplied as a dilute aqueous solution, making the product stable over time. Although there were problems in terms of stability, transportation, etc., the product of the present invention is preferable because it can be dissolved in water extremely easily in the same manner as conventional starch. Next, the present invention will be explained in more detail with reference to Examples. Example 1 Trimethylaminoethyl chloride etherified starch with a degree of etherification of 0.06 100 parts water 500 parts N.N.
After adding 10 parts of N-trimethyl-N-acryloyloxyethylammonium chloride, 10 parts of hydroxypropyl methacrylate, 10 parts of ceric ammonium nitrate, and 1 ml of nitric acid (63%), graft modification was performed at 45°C for 1 hour. , neutralization, washing and drying to obtain graft modified starch A. Example 2 100 parts of starch-polyvinyl alcohol graft copolymer with a graft ratio of 35%, 80 parts of water, 100 parts of isopropyl alcohol, 8 parts of 3-chloro-2-hydroxypropyltrimethylammonium chloride
1 part, 40 parts of Glauber's salt were dispersed, and 3% sodium hydroxide was added dropwise under stirring at 40°C, and the starch, which is the backbone polymer, and the polyvinyl alcohol part, which is the graft side chain, were cationized with a quaternary ammonium salt at pH 10.0 to 11.0. After reaction, the mixture was neutralized, washed and dried to obtain graft modified starch B. Example 3 Starch-poly-3-chloro-2 with a grafting rate of 40%
- 100 parts of hydroxypropyl methacrylate was dispersed in 1000 parts of trimethylamine (30% solution) and reacted at 40°C for 5 hours to introduce a quaternary ammonium salt into the graft side chain, then washed and dehydrated. Dispersed in 150 parts of water and 100 parts of acetone,
Add 15 parts of 2-chloroethyltrimethylammonium chloride and dropwise add 3% sodium hydroxide to react at 40°C for 10 hours at pH 10 to 11 to neutralize by introducing quaternary ammonium salt into the backbone polymer and graft side chains. , washed with water, and dried to obtain graft modified starch C. Comparative Example 1 Graft-modified starch D having a quaternary ammonium salt only in the side chain was obtained by performing the same operation as in Example 1 using terminally modified tapioca starch as a raw material instead of the trimethylaminoethyl chloride etherified starch in Example 1.
I got it. Example 4 Degree of etherification of starch, which is the backbone polymer of graft-modified starches A to D, with quaternary ammonium salt,
The nitrogen content of the graft side chain and the Bruckfield viscosity of a 1% aqueous solution at 20°C were determined and shown in Table 1.

[Table] Example 5 A paste-like shampoo was produced using a high-viscosity type carboxymethyl cellulose, which is currently commonly used as a thickening agent, and graft-modified starches A and D of the present invention in the following formulation as a shampoo for hair washing. We conducted a usage test. Thickening agent 2.0 Propylene glycol (plasticizer) 10.0 Water 45.15 Triethanolamine lauryl sulfate (for cleaning) 15.0 Sodium lauryl sulfate (for cleaning)
20.0 Sorbitol polyethylene oxide (modifier)
3.0 Sodium stearate (polishing agent) 2.0 Pigment 0.8 Flavor 0.05 Total amount 100.00wt%

[Table] Example 6 A comparative study was carried out by soaking tuna in ice glaze, which is a type of frozen preservation method, once in a 1% aqueous solution of the graft-modified starch A of the present invention and an additive-free aqueous solution.

[Table] Example 7 Thickening of urea-formalin resin: urea 120g (2.0
PH after mixing and adding 2.5 g of graft modified starch A to 308 g (3.8 mol) of 37% formaldehyde
After adjusting the pH to 8.5 and conducting an addition reaction at 90℃ for 60 minutes, lowering the temperature to 70℃ and adjusting the pH to 6.5, stirring for 60 minutes, cooling to 30℃ and neutralizing, the viscosity of the resin liquid was 700. It was centipoise hot. Comparative Example 2 In the same manner as in Example 7, 2.5 g of graft-modified starch D was added and the same reaction was carried out. The viscosity of the resin liquid is
It was 56 centipoise. Example 8 Organic sludge flocculation filtration test: Excess sludge (solid content: 1%) generated from a sewage treatment plant was used to add 100 ppm of each of the flocculating ability of graft-modified starches A to D and other various flocculants, and 100 ppm was added at 300 rpm. Stir for a minute. Next, this flocculated sludge liquid was poured into a Buchner funnel covered with a 120-mesh plain weave filter cloth, and the amount of filtrate over 15 seconds was measured.
The results are shown in Table-2.

【table】

Claims (1)

[Claims] 1 Quaternary ammonium-modified cation etherified starch with a degree of etherification of 0.001 to 0.5 is used as the backbone polymer,
The graft side chain has a cationic substituent modified with quaternary ammonium, the nitrogen content of the graft side chain is 0.01 to 3.0 parts based on 100 parts of the main polymer, and Bruckfield in a 1% aqueous solution at 20°C. Modified starch with a viscosity of 1000 centipoise or higher.