The method of obtaining acrylamide polymer containing hydroxamic group
(57) Abstract:Usage: obtain polymers with hydroxamic groups, used as flocculants. The inventive interaction of an aqueous solution acrylamide polymer with a concentration of at least 2 wt.% with a hydroxylamine salt at a molar ratio of hydroxylamine and amide groups in acrylamides the polymer is 0.1 to 2.0 : 1. The reaction is carried out at a pH value of at least 11, a temperature of 40 - 80oC for 1 - 4 h Molecular weight of the original polymer, which can be used acrylamide, 5 104- 15 106. 1 C. p. F.-ly, 7 PL. The invention relates to the synthesis from hydroxamic groups used in the formation of iron complexes; they show a beneficial effect on drilling muds.These polymers are used as flocculants.A method of obtaining these polymers by reacting hydroxylamine with polyacrylamide in aqueous solution at a temperature of 50-80aboutC and the pH value of 6.2 to 6.8. It is noted that this temperature range is optimal for minimizing the decomposition of hydroxylamine while maintaining the reaction rate in a reasonable dinnie examples have a molecular weight in the range 1000-20000.A method of obtaining hydroxamate polymers interaction of hydroxylamine with polyacrylamide at a temperature of 90aboutWith the use of sodium acetate as a buffer.Closest to the claimed is a method for polyacrylamide with hydroxamic groups interaction polyacrylamide (PAA) with hydrochloric acid hydroxylamine in aqueous medium in the presence of sodium hydroxide in an amount to provide a degree of neutralization of hydroxylamine (HA) 80% (the molar ratio of alkali and HA 0,4:0,5-0,7)  the Method allows to obtain PAA content hydroxamate groups of up to 31% In the known methods for decreasing the concentration of hydroxylamine is proportional decrease the reaction rate and efficiency of conversion of hydroxylamine in hydroxamate group. Thus, at low concentrations of hydroxylamine, which was tested by hydroxamate polymers, especially in the case of high-molecular compounds, the reaction rate and efficiency of hydroxylamine are critical parameters for determining the commercial success of the process.The aim of the invention is to provide a process in which the reaction rate and efficiency of use the steps acrylamide polymer with hydroxylamine is the pH value, close to the pKa of the latter. This is because when the pH is equal to pKa, the concentration of hydroxylamine and hydroxylamine salt serving as a catalyst for the reaction, the same.Applicants have found that in the case of polymers the reaction rate suddenly increases with increasing pH and, moreover, there is an optimization of the efficiency of use of hydroxylamine. In accordance with the proposed applicants in a new way, thus, achieved an increase of hydroxamate per unit used hydroxylamine.The invention consists in the fact that interact aqueous solution acrylamide polymer with a molecular weight of 15 10415 106with a salt of hydroxylamine at pH of at least 11. When the molar ratio of hydroxylamine and amide groups in acrylamides the polymer is about 0.1 to 2.0. The reaction temperature 40-80aboutWith time 1-4 hours and the concentration of the polymer solution, at least 2 wt.In this process, the feedstock may be used any water-soluble or water-dispersible acrylamide polymer. Preferred are such compounds as polyacrylamide, polymethacrylamide, etc. but what of iMER, triple polymer, etc., up to 90%, preferably 50% including monoethylene unsaturated comonomer capable copolymerisate with the specified acrylamide. Suitable for these purposes, the copolymers include acrylic acid, methacrylic acid, 2-acrylamide-2-methylpropanesulfonic acid, alkalemia esters of acrylic and methacrylic acids such as methyl acrylate, acrylate, methyl methacrylate, butyl acrylate, telemetries, etc., sodium acrylate, vinyl acetate, vinyl pyrrolidone, styrene, Acrylonitrile, etc. due To the fact that these polymers are used in aqueous solution, then with increasing molecular weight of the polymer is required and a greater dilution of the solution.Among the suitable hydroxylamine salts include phosphate, perchlorate, sulfate, sulfite, hydrochloride, acetate, propionate, etc., is Preferred sulfate.At low reaction time, the degree of hydroxamate in the polymer is relatively low. The increase in time of the interaction leads to a slight increase.The effectiveness of the interaction from the point of view of the degree of hydroxamate increases at lower temperatures, however, the reaction rate decreases. Preferred temperaturregler.As mentioned above, the most important condition for carrying out this process is the pH value.The excess of ammonia formed during the reaction, can be eliminated by heat, vacuum or pumping system with an inert gas.Below are examples illustrating the invention.P R I m e R s 1 and 2. A number of reactions to determine the influence of pH on the interaction of hydroxylamine with polyacrylamide. Used polyacrylamide has a molecular weight of 50000-60000. It was obtained by the polymerization of acrylamide in aqueous solution in the presence of ammonium sulfate or metabisulfite sodium as a catalyst. The reaction with hydroxylamine is carried out at concentrations of polyacrylamide 2.8 mol/l hydroxylamine of 1.27 mol/l (added as hydroxylamine sulphate) at a temperature of 80aboutC. hydroxylamine Sulfate is dissolved in water and treated with an appropriate base upon cooling. The resulting solution is added to a solution of polyacrylamide with stirring and the corresponding temperature. At equal intervals of time selected multiples of the amount of the mixture and analyzed in order to establish unreacted hydroxyl is trated acid with subsequent ion chromatographic analysis released by the hydroxylamine or13WITH NMR. The content of carboxylate define method13WITH NMR. Unreacted hydroxylamine determined by iodometric titration. In table. 1 shows that the highest rates are achieved with high initial pH values (examples 1 and 2). The value of hydroxamate in such experiments is also higher.P R I m e R s 3-6. Polyacrylamide of example 1 and 2 the concentration of 1.41 mol/l (10 wt.) subjected to interaction with NH2HE (in the form of hydroxylamine sulphate concentration was 0.63 mol/l at a temperature of 80aboutC). Add enough NaOH to neutralize the sulfate hydroxylamine and additionally excess Paon, as indicated in the table. 2, which presents the results of kinetic studies. Despite the fact that even the lowest pH value (or the concentration of the base) are quite significant, however, there is still a rapid increase in velocity with increasing concentration.P R I m e R s 7-11. The polymers of examples 1 and 2 are subjected to interaction similar to that described in examples 3-6 except that the concentration of polymer is 0.70 mol/l (5 wt.), and Na2OH 0.32 mol/L. the Results are shown in table. 3.In this case, the end Levels of hydroxamate usually lower than in examples 3-6, where the concentration of the polymer was higher.P R I m e R s 12-15. To obtain the results shown in the table. 4, the polymers of examples 1 and 2 are subjected to interaction similar to examples 3-6 except that the concentration of the polymer is of 0.28 mol/l (2 wt.) Na2OH 0.13 mol/L.P R I m e R s 16-19. Follow the procedure in examples 12-15, with the peculiarity that the concentration of polyacrylamide is 2 wt. and the reaction is carried out at a temperature of 60aboutC. the Results are shown in table. 5.P R I m e R s 20-23. Repeat the procedure of examples 12-15, with the peculiarity that the reaction is carried out at a temperature of 40aboutC. the Results are shown in table. 4. Increases the reaction rate and the level of final hydroxamate when the concentration of NaOH with 2.0 mol/l to 4.0 mol/L. Thus, when the temperature of the 40aboutWith the speed of hydroxamate great at high pH values.P R I m e R s 24-30. Follow the procedure described in examples 1 and 2, with the peculiarity that the polyacrylamide has a molecular weight of about 15 million, using different concentrations of polymer and hydroxylamine in the feedstock, and the reaction is carried out at different meant the ri same ratio polymerizability, there is a growing adoption of hydroxamate with increasing pH values. Comparing the data for examples 27-30 those shown in the table. 5 for a polymer with a lower molecular weight suggests that when conducting the reaction in substantially the same conditions, there is almost the same sensitivity to hydroxamate.P R I m e R 31. Follow the procedure as described in examples 1, 2, but using salt and hydrochloride. Similar ndings.P R I m e R 32. Follow the procedure in examples 1 and 2, with the peculiarity that the polymer is a copolymer (molecular weight 72000) acrylamide and acrylic acid (90:10), with similar ndings.P R I m e R s 33-37. Follow the procedure described in example 32, but instead of the copolymer using the following polymers:
P R I m e R 33 acrylamide (sodium acrylate (60:40), molecular weight of 120,000.P R I m e R 34 polymethacrylamide, molecular weight 2000000.P R I m e R 35 acrylamide/Acrylonitrile (70:30), molecular weight of 8000.P R I m e R 36 acrylamide (acrylate (80:20), molecular weight 8000000.P R I m e R 37 acrylamide/acrylic acid/styrene (80:10:10), a molecular weight of 800000.In each case obtained almost equivalent results.doxylamin in example 40 on phenylhydroxylamine led to the achievement of similar hydroxamate polymer in all cases. 1. The METHOD of OBTAINING ACRYLAMIDE POLYMER CONTAINING HYDROXAMIC GROUP, by treatment of an aqueous solution acrylamide polymer salt of hydroxylamine in the presence of sodium hydroxide at a molar ratio of hydroxylamine salt and an amide group in the original polymer, 0.1 - 2 : 1, characterized in that use acrylamide polymer (mol.m. 5 104- 15 106and the treatment is carried out at a pH of at least 11, at a temperature of 40 - 80oC for 1 to 4 h and the solution concentration of the polymer is at least 2 wt.%:
2. The method according to p. 1, characterized in that as acrylamides of polyacrylamide polymer used.
FIELD: paper-and-pulp industry.
SUBSTANCE: : process comprises preparation of paper pulp, flocculation of pulp, shear force-involving mechanical treatment of pulp, second flocculation of pulp, drainage of pulp on the screen to form sheet, and subsequent drying of sheet. Flocculation is carried out by adding water-soluble optionally having intrinsic viscosity above 3 dl/g. Polymer is further characterized by oscillation delta tangent value at 0.005 Hz above 1.1.
EFFECT: improved drainage and retention on moving screen, and formation process.
10 cl, 1 dwg, 4 tbl, 4 ex
FIELD: chemical industry, chemical technology, polymers.
SUBSTANCE: invention relates to a method for preparing aqueous polymer dispersions of the multipurpose designation. Method for preparing an aqueous dispersion of styrene-acryl copolymer is carried out by preliminary emulsifying a mixture of acrylic monomers with styrene in the presence of emulsifying agent and the following aqueous-emulsion co-polymerization of the reaction mixture in the presence of initiating agent. Monomer mixture comprises additionally acrylamide, and method involves using ammonium persulfate and hydrogen peroxide as an initiating agent. Method involves the successive fractionally dosing feeding ammonium persulfate for two stages followed by addition of a mixture of polymethylsiloxane of molecular mass 55-1000 Da and iron sulfate in their mass ratio = (25-35):1 to the reaction mixture at stirring, cooling the reaction mass and its neutralization to pH = 5-6. Invention provides preparing the stable aqueous polymeric dispersion with diminished size of particles. Invention provides enhancing strength and water resistance of film prepared on its base.
EFFECT: improved preparing method.
1 tbl, 3 ex
FIELD: polymer production.
SUBSTANCE: invention provides composition for preparation of gradient hydrogel polymer material based on copolymers of acrylamide and N,N'-methylene-bis-acrylamide representing following system: (i) mixture of dilute solution containing 2-3% acrylamide, 0.1-0.2% N,N'-methylene-bis-acrylamide, 0.01% ammonium persulfate, and, as viscosity regulator, 0.5-2.0% glycerol or 1:1 mixture of glycerol and polyvinyl alcohol, each taken in amount 3.5-8.0%, in bidistilled water and (ii) and concentrated solution containing 6-45% acrylamide, 0.6-1.0% N,N'-methylene-bis-acrylamide, and 0.04% ammonium persulfate in bidistilled water, said dilute solution constituting 75-80% and said concentrated solution 20-25% of the total weight of the system. Components are distributed in gradient manner in final system. Invention also discloses a method of preparing gradient hydrogel polymer material based on above-indicated copolymers and indicated gradient hydrogel polymer material. Value and direction of gradient of modulus of elasticity of hydrogel polymer materials is controlled by concentration of viscosity regulator.
EFFECT: expanded possibilities for preparing gradient hydrogel polymer materials.
3 cl, 1 tbl, 8 ex
FIELD: polymer production.
SUBSTANCE: invention relates to a method for production of high-molecular weight water-soluble polymers used as flocculant at enterprises of water conditioning, petroleum processing, petrochemistry, iron and nonferrous metallurgy, paper-and-pulp, varnish-and-paint, chemical, and other industries. In particular, invention provides a method for production of high-molecular weight (meth)acrylic anionic flocculant via copolymerization of water-soluble anionic ethylenically unsaturated monomer with nonionic ethylenically unsaturated monomer, the former being salt of (meth)acrylic acids and the latter (meth)acrylic acid amide and ester at salt/amide/ester ratio 100:10:(1-6) or 100:(1-6):10. Proposed method leads to production of high-molecular weight (meth)acrylic anionic flocculant in the form of powder with nearly 100% content of principal substance, which is well dissolved in water.
EFFECT: enhanced efficiency in treatment of various disperse systems (industrial effluents).
3 cl, 4 tbl, 4 ex
FIELD: medicine-destination polymers.
SUBSTANCE: invention relates to biologically stable hydrogels to be employed as endoprosthesis consisting essentially of following components: polyacrylamide including acrylamide, crosslinked methylene-bis-acrylamide, wherein acrylamide and methylene-bis-acrylamide are linked at molar ratio from 150:1 to 1000:1. Hydrogel is rinsed with water or physiologic solution so that it contains about 0.5-3.5% polyacrylamide and less than 50 ppm acrylamide and methylene-bis-acrylamide monomers, while modulus of elasticity of hydrogel is approximately 10 to 700 Pa and its complex viscosity about 2 to 90 Pa*sec. Rinsing stage allows removal of nearly all amounts (even trace amounts) of above-indicated monomers resulting in lower toxicity and higher stability of hydrogel. Biologically stable hydrogel is used as injectable prosthesis to fill soft tissues and also to treat or prevent urinary incontinence or anal incontinence. Hydrogel, obtained in a few stages including combining acrylamide and methylene-bis-acrylamide, initiating radical polymerization, and rinsing with apyrogenic water or physiologic solution, is also useful in treatment or prevention of bladder-ureter reflux in mammalians. In all these cases biologically stable hydrogels contain between 0.5 and 25% polyacrylamide.
EFFECT: enlarged resource for manufacturing endoprostheses.
10 cl, 3 dwg, 7 tbl
FIELD: chemistry of polymers.
SUBSTANCE: invention describes polyelectrolytes synthesized by polymerization of (meth)acrylamide monomers quaternized (meth)acrylamide derivative, (meth)acrylic acid derivative and/or cationic monomers resistant to hydrolysis. Composition of polyelectrolytes is characterized by the following toxicity index: Fi = (Qtr-2QME)/10≤1 wherein Qtr is a general polymer charge; QME is part of monomer charge of ester type. Proposed polyelectrolytes are used for dehydration of cleared slimes, sewage treatment, preparing drinking water or for producing paper or cardboard.
EFFECT: valuable properties of polyelectrolytes.
15 cl, 4 tbl, 12 ex
SUBSTANCE: there is disclosed water-soluble cation-active powdered polymer composition contains, at least, two cationic polymers of different molecular weight. The first cationic polymer consists of component monomers by radical polymerisation in aqueous solution with the second cationic polymer added whereat cation link types of the first and second polymers are matched. The first cationic polymer is a copolymer of cationic and nonionic monomers. Apparent molecular weight of the first cationic polymer is more than 1 million. The first cationic polymer is polymerised in aqueous solution of the second cationic polymer by adiabatic gel polymerisation method. Ratio of the second cationic polymer to the first cationic polymer is 0.01:10 to 1:3. Besides, there is described method of making these polymer compositions and their application as a flocculating additive for solid substance/liquid isolation.
EFFECT: developed effective method of producing water-soluble cationic polymer composition.
15 cl, 20 ex, 1 tbl
SUBSTANCE: invention refers to method for producing biosoluble copolymers of medical acrylamide, vinylpyrrolidone and alkylacrylate to be used for eye medicated film manufacturing. Method consists in radical copolymerisation of acrylamide, vinylpyrrolidone and alkylacrylate in ratio as follows, wt %: acrylamide 50-70, vinylpyrrolidone 15-25, alkylacrylate 15-25. Method includes the procedures as follows. At first water, initiator, acrylamide, vinylpyrrolidone are charged in amount 70-90 % of total vinylpyrrolidone volume. The mixture is heated up to temperature 70-90°C and within 0.5-1 hours stirred vinylpyrrolidone mixture in amount 10-30 wt % of total vinylpyrrolidone, initiator and alkylacrylate volume is ntroduced. Total monomer concentration in the reaction mixture is 5-30 wt %. Within 2-3 hours the mixture is exposed to the specified temperature. Hydrogen peroxide is added in amount 0.1 to 2 wt % of total monomer weight with additional stirring at polymerisation temperature within 1-3 hours. Further the reaction mass is cooled to temperature 30-45°C. Acetone is added to form coacervate copolymer solution. Mixed water - acetone are decanted. Chloroform is added in volumetric ratio coacervate solution - chloroform 1:0.5 to 1:2, and stirred. After that chloroform is separated, water is added to copolymer concentration 10-35 wt %. While stirring acetone is added in volumetric ratio solution - acetone 1:2 to 1:4. Then sediment is filtered, and copolymer is dried at temperature 80-100°C within 2-6 hours.
EFFECT: making of high yield copolymer of fast swelling capacity and solubility in aqueous environments, formability to viscous solutions, prolong drug release.
tbl, 3 ex
SUBSTANCE: there is disclosed water-soluble powdered cation-agent polymer compound containing at least two cationic polymers differing by cationic types with the first cationic polymer made of composing monomers by radical polymerisation in aqueous solution with the second cationic polymer added. The first cationic polymer is polymerised in an aqueous solution of the second cationic polymer by adiabatic gels-polymerisation. Ratio of the second cationic polymer to the first cationic polymer is 0.01:10 to 1:4. Additionally there is disclosed method of producing this polymeric compound applied as an auxiliary flocculative agent in solid/liquid separation.
EFFECT: extended application of the compound.
22 cl, 28 ex, 6 tbl
SUBSTANCE: present invention relates to water-in-water cationic polymer dispersions. A water-in-water polymer dispersion is described, containing cationic polymer A and at least one dispersant B, characterised by that, the said polymer A is formed from: a1) 1 to 60 wt % of cationic monomers of the type of cationised dialkylaminoalkyl (meth)acrylates and a2) 40 to 99 wt % of nonionic monomers, and that said polymeric cationic dispersant B is formed from 100 wt % of cationised dialkylaminoalkyl(meth)acrylamides and has average molecular weight Mw from 75000 to 350000 g/mol. Also described is a method of producing said water-in-water polymer dispersions from cationic polymer A and at least one polymeric cationic dispersant B, characterised by that, in the polymerisation reactor, aqueous solution of the polymeric cationic dispersant B with average molecular weight from 75000 to 350000 g/mol is synthesised from 100 wt % cationised dialkylaminoalkyl(meth)acrylamides, and a monomer mixture a1) 1 to 60 wt % cationised dialkylaminoalkyl (meth)acrylates and a2) 40 to 99 wt % of nonionic monomers, which are combined, with addition of free-radical initiators, and free-radical polymerisation of the monomer mixture is carried out. Also described is use of said water-in-water polymer dispersion as a flocculant in precipitation of solids, preferably in water and treatment of water or waste water purification, in extraction of raw materials, preferably coal, aluminium or petroleum, or as demulsifier in the separation of aqueous mixtures containing oil and/or fat, as a preservative and dehydrating agent in paper production, as thickener, as well as an additive in phytosantitary reagent, optionally together with other biologically active substances as an additive in anti-erosion reagent.
EFFECT: avoiding rheological problems during production of said polymer dispersion, high stability of polymer dispersion with respect to its rheological behaviour during storage.
27 cl, 12 tbl, 18 ex
SUBSTANCE: ophthalmic article is made of hydrogel as a cross-linked polymer matrix and contains at least one water-soluble, non-reactive hydrophilic polymer containing less than 20 mole % of anionic repeating units and repeating units derived from a compound of formula I where R1 is hydrogen or methyl; R2 is H or C1-4 alkyl substituted by at least one hydroxyl group; R3 is C1-4 alkyl substituted by at least one hydroxyl group. The water-soluble hydrophilic polymer has a polymerization degree of 100 to 100,000, and is free of end hydrophobic polymer units. Method for ophthalmic article wettability improvement includes ophthalmic article contacting with a solution containing at least one of the above water-soluble nonreactive hydrophilic polymer, under conditions sufficient for inclusion of an effective lubricant quantity of hydrophilic polymer into the ophthalmic article. The ophthalmic solution contains from 10 m. p. and to 10 wt % of at least one water-soluble, nonreactive hydrophilic polymer.
EFFECT: invention allows to increase the wettability of an ophthalmic article without surface treatment.
29 cl, 1 tbl, 1 ex
SUBSTANCE: initially, seed particles comprising a hydrophobic polymer are introduced into an aqueous suspension. Then, the seed particles are promoted in the aqueous suspension to form a dispersed phase. Thereafter, a hydrophilic monomer comprising an acrylamide monomer having a hydrophobic protecting group in a dispersed phase, with a diacrylamide crosslinker having a hydrophobic protecting group, is polymerized. A polymer particle is obtained which is a hydrogel particle comprising a plurality of hydrophobic protecting groups. At least a portion of the hydrophobic protecting groups is removed from the polymer particle and a hydrophilic particle is obtained. Then, an oligonucleotide is bound to the hydrophilic particle. In one embodiment of the process, a plurality of hydrophobic protecting groups is cleaved from the hydrophilic polymer obtained in the polymerization step and the hydrophobic polymer is extracted from the polymer particle to obtain a hydrogel particle.
EFFECT: invention allows to obtain particles that can effectively bind to polynucleotides.
73 cl, 2 dwg, 1 tbl, 25 ex