Crystal form of sodium 2-acrylamido-2-methylpropanesulfonate

Abstract

The present invention relates to a crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate, ATBS.Na, having a powder X-ray diffraction pattern that includes peaks at positions where the 2θ angle (±0.1°) is 11.7°;12.2°;13.2°;13.5°;15.6°;16.8°;17.8°;18.5°;19.1°;20.6°;21.4°;23.3°;25.1°;25.8°;26.9°;29.1°;29.5°;31.0°;33.0°;33.6°;34.4°;35.2°;35.9°;37.1°;38.4°;39.6°;41.1°;42.9°;45.1°;46.0°;47.2°;47.6°.

Description

[Technical Field]

[0001] The present invention relates to the crystalline form of 2-acrylamido-2-methylpropanesulfonic acid. More specifically, the present invention relates to the crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate. The present invention also relates to a method for obtaining the crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate, and polymers obtained from this crystalline form. [Background technology]

[0002] 2-acrylamido-2-methylpropanesulfonic acid, also known as ATBS, is widely used in various fields, including the petroleum and gas industry, mining, construction, textiles, water treatment (seawater desalination, mineral industry, etc.), and cosmetics, as an additive to acrylic fibers, or as a raw material for manufacturing polymers used as dispersants, thickeners, friction reducers, flocculants, or superabsorbents.

[0003] The reaction carried out in the method for producing ATBS corresponds to the following reaction scheme, in which acrylonitrile is present in excess during the reaction to serve as both the reaction solvent and the reagent. Acrylonitrile is brought into contact with fuming sulfuric acid (oleum) and isobutylene.

[0004] [ka]

[0005] One of the by-products that can be generated during this synthesis is acrylamide.

[0006] ATBS is insoluble in acrylonitrile solvent. As a result, the reaction product exists as crystals suspended in the reaction solvent.

[0007] For example, U.S. Patent No. 6,448,347 and Chinese Patent No. 102351744 describe a method for the continuous production of ATBS. The ATBS is then typically separated from acrylonitrile by filtration and subsequently dried.

[0008] To reduce the amount of acrylonitrile and acrylamide remaining in the crystals, it is necessary to dry the ATBS. These two compounds are classified as carcinogenic, mutagenic, or reproductively toxic (CMR). Therefore, in order to lower the levels of acrylonitrile and acrylamide, it is necessary to dehydrate the acrylonitrile as thoroughly as possible by effective filtration, and then dry the ATBS.

[0009] Those skilled in the art will recognize that ATBS crystals have a crystallographic configuration that produces needle-shaped solids.

[0010] Needle-shaped crystals are known to those skilled in the art to have macroscopic properties that make handling and transporting the solid difficult (low solid fluidity, caking, low resistance to shear stress), and processing difficult (low filtration, difficulty in drying, abrasion).

[0011] In the case of ATBS, further problems generally arise from the small particle size of the needle-like crystals, the density of the solid in question, and the explosiveness of the fine dust.

[0012] These macroscopic properties are directly related to the morphology and specific surface area of ​​the crystal. Acicular crystals have a large specific surface area.

[0013] International Publication No. 2009 / 072480, Japanese Patent Publication No. 2008-307822, and Japanese Patent Publication No. 2003-137857 describe the acquisition of ATBS needle-shaped crystals.

[0014] International Publication No. 2018 / 172676, filed by the present applicant, describes a novel form of ATBS crystals referred to as "hydrated crystalline form of ATBS." This novel crystalline form has different physicochemical properties from acicular ATBS and imparts improved properties to polymers containing this novel form of ATBS.

[0015] However, ATBS, in any form, remains a strong acid due to its sulfonic acid functional group and is highly corrosive to metals. Due to the powdery nature of 2-acrylamido-2-methylpropanesulfonic acid powder, there is also a risk of chemical burns from airborne particles coming into contact with skin or eyes, or being inhaled into the lungs during handling.

[0016] ATBS must be in aqueous form when used in polymerization. The aqueous phase may be used as is, i.e., in acid form, or as a salt obtained by reacting the acid with an alkali metal, alkaline earth metal, or a molecule containing an unsubstituted or substituted amine functional group.

[0017] The shelf life of this aqueous solution is generally short. This is because self-polymerization occurs due to exposure to contaminants such as iron or its oxidized forms, which can result from corrosion of metal pipes or containers caused by temperature, UV light, or the acidic form of ATBS. In addition, the temperature rise caused by the self-polymerization of ATBS far exceeds the boiling point of water, increasing the pressure inside the container and potentially causing an explosion. Therefore, self-polymerization poses a certain risk to the safety of personnel and equipment. [Overview of the project] [Problems that the invention aims to solve]

[0018] The applicant has discovered a novel form of ATBS, referred to as "crystalline form of sodium 2-acrylamido-2-methylpropanesulfonic acid." This novel form avoids the intermediate step of forming the ATBS salt from acid, while simultaneously improving its physicochemical and application properties (similar to the "hydrated crystal" form). It also reduces the risks of combustion, corrosion, and self-polymerization. Finally, this crystalline form of the sodium salt has a longer shelf life than an aqueous solution of sodium 2-acrylamido-2-methylpropanesulfonic acid.

[0019] 2-acrylamido-2-methylpropanesulfonate sodium salt will be referred to as "ATBS.Na" below.

[0020] The use of the crystalline form of ATBS.Na according to the present invention is consistent with environmental awareness principles and the impact that industry and humanity have on the planet. The novel form of the product means that it is safer for handlers to use and the energy load is reduced because the chlorination step (chlorination of ATBS) is no longer required during the polymerization of 2-acrylamido-2-methylpropanesulfonic acid, and because it is in powder form (100% in powder compared to a maximum of 50% in solution) which allows for the transport of more active raw material components. Furthermore, the improved shelf life of the product also means a reduction in waste caused by the increased amount of product input required as a result of the performance degradation of overaged products. In addition, the improved performance of polymers obtained from the crystalline form of the sodium salt of the present invention helps to reduce the amount of product required for the applications in which they are used, resulting in a reduction in overall water consumption and greenhouse gas emissions such as CO2. [Means for solving the problem]

[0021] The object of the present invention is a specific form of 2-acrylamido-2-methylpropanesulfonic acid, which will hereafter be referred to as "crystalline form of 2-acrylamido-2-methylpropanesulfonic acid sodium salt".

[0022] The present invention also relates to a method for producing the crystalline form of 2-acrylamido-2-methylpropanesulfonate sodium salt (ATBS.Na).

[0023] The present invention also relates to the use of the aforementioned crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate salt for producing water-soluble, water-swellable, or highly absorbent polymers.

[0024] The present invention also relates to the use of polymers at least partially obtained from the crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate in the following applications: well drilling or cementing; conformance, diversion; open, closed, or semi-closed circuit water treatment; fermentation broth treatment; sludge treatment; construction; paper or cardboard manufacturing; batteries; wood treatment; hydraulic composition (concrete, cement, mortar, and aggregates); cosmetic preparation; detergent preparation; textile manufacturing; geothermal energy; diaper manufacturing; or agriculture.

[0025] Finally, the present invention also relates to the use of polymers at least partially obtained from the crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate as a coagulant, binder, viscosity reducer, thickener, absorbent, water remover, filler retainer, dehydrating agent, conditioning agent, stabilizer, fixative, film-forming agent, sizing agent, superplasticizing agent, clay inhibitor or dispersant. [Modes for carrying out the invention]

[0026] The term "polymer" should be understood to mean a homopolymer or copolymer. The term "copolymer" should be understood to mean a polymer obtained from at least two different monomers. Therefore, it may be a copolymer of at least two monomers selected from hydrophilic anionic monomers, hydrophilic cationic monomers, hydrophilic nonionic monomers, hydrophilic zwitterionic monomers, hydrophobic monomers, and mixtures thereof.

[0027] The term "hydrophilic monomer" refers to an octanol-water partition coefficient K of 1 or less. ow It should be understood that this refers to a monomer having a partition coefficient K ow It is identified in a 1:1 volume ratio octanol-water mixture at 25°C and a pH of 6–8.

[0028] The term "hydrophobic monomer" refers to an octanol-water partition coefficient greater than 1 K ow It should be understood that this refers to a monomer having a partition coefficient K ow It is identified in a 1:1 volume ratio octanol-water mixture at 25°C and a pH of 6–8.

[0029] The terms "crystal" or "crystalline form" refer to a solid material in which its constituent elements (atoms, molecules, or ions, etc.) are arranged in a highly regular microscopic structure, forming a crystalline lattice that extends in all directions. Amorphous solids are not included.

[0030] Octanol-water partition coefficient K ow This represents the concentration (g / L) ratio of monomers between the octanol phase and the aqueous phase. This is defined as follows:

[0031]

number

[0032] According to the definition, a water-soluble polymer is defined as 10 g / L while stirring at 25°C. -1This refers to a polymer that, when dissolved in water at a certain concentration, yields an aqueous solution.

[0033] "X and / or Y" should be understood to mean "X" or "Y" or "X and Y".

[0034] The present invention also includes all possible combinations of the various embodiments disclosed, whether they are preferred embodiments or given as examples. Furthermore, where ranges of values ​​are indicated, limit values ​​are included within those ranges. The disclosure also includes all combinations between the limit values ​​of these ranges. For example, the value range "1 to 20, preferably 5 to 15" means the ranges "1 to 5", "1 to 15", "5 to 20", and "15 to 20", as well as the disclosure of the values ​​1, 5, 15, and 20.

[0035] Crystalline form of sodium salt of 2-acrylamido-2-methylpropanesulfonic acid The present invention relates to the crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate having a powder X-ray diffraction pattern with peaks at 2θ angles of 11.7°; 12.2°; 13.2°; 13.5°; 15.6°; 16.8°; 17.8°; 18.5°; 19.1°; 20.6°; 21.4°; 23.3°; 25.1°; 25.8°; 26.9°; 29.1°; 29.5°; 31.0°; 33.0°; 33.6°; 34.4°; 35.2°; 35.9°; 37.1°; 38.4°; 39.6°; 41.1°; 42.9°; 45.1°; 46.0°; 47.2°; and 47.6°. The uncertainty of these peaks is generally on the order of ±0.1°.

[0036] X-ray crystallography, radiation crystallography, or X-ray diffraction is an analytical technique used to investigate the structure of crystalline materials at the atomic scale. It is based on the physical phenomenon of X-ray diffraction. Diffractometers using a copper source may be employed.

[0037] Powders formed from a specific crystal phase always produce diffraction peaks in the same direction. This diffraction pattern thus forms the true signature of the crystal phase. Therefore, it is possible to identify the nature of each crystal phase within a mixture or pure product.

[0038] This signature is specific to each organic or inorganic compound and is in the form of a list of peaks located at an angle of 2θ (2-theta).

[0039] This technique is used for the characterization of different crystal forms of a substance, also known as polymorphs, which can exist for the same chemical molecule.

[0040] Another aspect of the invention relates to the crystal form of ATBS.Na having a Fourier transform infrared spectrum containing peaks at 3576 cm -1 , 3485 cm -1 , 3310 cm -1 , 3079 cm -1 , 2975 cm -1 , 1658 cm -1 , 1629 cm -1 , 1543 cm -1 , 1403 cm -1 , 1321 cm -1 , 1301 cm -1 , 1205 cm -1 , 1187 cm -1 , 1163 cm -1 , 1046 cm -1 , 980 cm -1 , 629 cm -1 . The uncertainty of these peaks is generally of the order of ±8 cm -1 .

[0041] Infrared measurements are carried out by Fourier transform using, for example, a Perkin Elmer Spectrum 100 spectrometer with an accuracy of 8 cm -1 equipped with a single reflection ATR polarization accessory.

[0042] Fourier transform infrared spectroscopy is the analysis of vibrations emitted, absorbed, or scattered by molecules. This technique is highly sensitive to so-called short interactions (the influence of a unit mesh on bonding). In most cases, the Fourier transform infrared spectra of different crystal systems differ significantly. Therefore, the Fourier transform infrared spectra reflect the details of the crystal structure of organic compounds.

[0043] Generally, and unless otherwise specified, X-ray diffraction patterns and infrared spectra are obtained at 20°C and an absolute pressure of 1 atmosphere (101,325 Pa).

[0044] Another aspect of the present invention relates to a crystalline form of ATBS.Na having a minimum ignition energy of more than 500 mJ, preferably more than 1000 mJ.

[0045] Minimum ignition energy represents the minimum energy required to ignite a compound. This energy can be electrical or thermal. Minimum ignition energy is essential information when considering the risk of explosion during product handling (transportation, storage, reaction, molding, etc.).

[0046] The minimum ignition energy depends on the properties (composition) of the powder and its polymer structure (particle size, crystal form, specific surface area).

[0047] For solids, this energy represents the minimum energy required for an electric spark that is likely to ignite cloud-like dust. The higher the minimum ignition energy, the lower the risk the solid poses when used, handled, or stored.

[0048] The minimum ignition energy is measured according to the NF EN 13821 standard.

[0049] Another aspect of the present invention relates to the crystalline form of ATBS.Na that exhibits four thermal phenomena at 49.8°C, 144.8°C, 169.8°C, and 254.3°C, as determined by differential scanning calorimetry. The uncertainty regarding the observation of these phenomena is generally on the order of 10°C (±10°C), and preferably on the order of 5°C or less.

[0050] The aforementioned thermal phenomenon is measured by differential scanning calorimetry (DSC). This technique uses the measurement of the change in heat associated with the thermal denaturation of a compound when the compound is heated at a constant rate, for example, at a heating rate of 10°C / min.

[0051] Method for producing the crystalline form of sodium salt ATBS.Na The present invention also relates to a method for producing the crystalline form of ATBS.Na, comprising at least the following sequential steps. 1) To form an aqueous solution or aqueous suspension SA2, mix ATBS with an aqueous solution SA1 and at least one sodium salt base, preferably for at least 1 minute; 2) To form suspension S1, distill the aqueous solution SA2 or aqueous suspension SA2 at a pressure of 700 mbar or less; 3) The suspension S1 is subjected to solid-liquid separation, and the crystals of the suspension S1 obtained at the end of step 2) are isolated in the form of composition C1. The resulting crystal is the aforementioned crystalline form of the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid.

[0052] In step 1), "sodium salt base" should be understood to mean at least one inorganic sodium salt Brønsted base, such as sodium hydroxide, sodium carbonate, sodium bicarbonate, or a mixture thereof.

[0053] The temperature and mixing time in step 1) can vary, in particular, depending on the concentration of ATBS. Those skilled in the art will know how to adjust the temperature and mixing time to optimize crystal formation.

[0054] The method for producing the crystalline form of ATBS.Na can be carried out for any form of ATBS, such as needle-shaped or hydrated forms.

[0055] The above manufacturing method may be carried out with ATBS of any purity.

[0056] Therefore, the above method can be implemented as a subsequent step in any type of ATBS manufacturing method. Furthermore, it can be applied to ATBS of any form, whether amorphous or crystalline, that has already been obtained.

[0057] Step 1 of the method for producing the crystalline form of ATBS.Na): ATBS is produced by the manufacturing methods described above (acrylonitrile, fuming sulfuric acid, and isobutylene). ATBS may be in the form of a fine powder, or it may be molded under controlled conditions by methods such as compression, granulation, or extrusion.

[0058] The addition of ATBS to the aqueous solution SA1 may be carried out before, after, or in parallel with the sodium salt base, preferably in parallel. Preferably, the aqueous solution SA1 is water.

[0059] The sodium salt base may be added as an aqueous solution. In this case, part or all of the aqueous solution of the sodium salt base may be aqueous solution SA1.

[0060] Advantageously, the concentration of ATBS sodium salt in the aqueous solution or aqueous suspension SA2 is 1% by weight to the saturation concentration, preferably 10% by weight to the saturation concentration, more preferably 20% by weight to the saturation concentration, more preferably 30% by weight to the saturation concentration, more preferably 40% by weight to the saturation concentration, and even more preferably 50% by weight to the saturation concentration, based on the weight of the aqueous solution or aqueous suspension SA2.

[0061] The ATBS and the sodium salt base may be added all at once or in several stages. It is preferable that they be added all at once.

[0062] When added in several stages, the ATBS and the sodium salt base are added in portions.

[0063] When the ATBS and the sodium salt base are added in portions, there is no limit to the number of portions, and advantageously there are at least two portions, preferably at least three portions.

[0064] There are no restrictions on the order in which the ATBS and the sodium salt base are added. They may be added simultaneously (i.e., in parallel), one by one in sequence (first the ATBS, then the sodium salt base, or vice versa), or in a different manner (first portion of ATBS, then first portion of the sodium salt base, then second portion of ATBS, then second portion of the sodium salt base, etc.), and preferably they are added simultaneously.

[0065] If these are added one by one in sequence or by other means, the addition of the second compound (whether the ATBS or the sodium salt base) may begin before the addition of the first compound is completed.

[0066] The first portion F1 of ATBS advantageously corresponds to at least 1 mol%, preferably at least 5 mol%, more preferably at least 10 mol%, even more preferably at least 15 mol%, and even more preferably at least 20 mol% of the total ATBS present in the aqueous solution or aqueous suspension SA2.

[0067] The second portion F2 of ATBS advantageously corresponds to at least 1 mol%, preferably at least 5 mol%, more preferably at least 10 mol%, even more preferably at least 15 mol%, and even more preferably at least 20 mol% of the total ATBS present in the aqueous solution or aqueous suspension SA2.

[0068] The third portion F3 of ATBS advantageously corresponds to at least 1 mol%, preferably at least 5 mol%, more preferably at least 10 mol%, even more preferably at least 15 mol%, and even more preferably at least 20 mol% of the total ATBS present in the aqueous solution or aqueous suspension SA2.

[0069] In a particular embodiment, the method is carried out continuously, in which case the ATBS and the sodium salt base are added continuously.

[0070] The amount of ATBS in the aqueous solution or aqueous suspension SA2 is advantageously 10 to 90% by weight, preferably 20 to 85% by weight, and more preferably 30 to 80% by weight, relative to the total weight of the aqueous solution or aqueous suspension SA2.

[0071] The mixing step 1) (ATBS + sodium salt base) is advantageously carried out at a temperature of 0 to 90°C, preferably 5 to 60°C, more preferably 10 to 40°C, in order to obtain an aqueous solution or aqueous suspension SA2.

[0072] In certain embodiments, the aqueous solution or aqueous suspension SA2 may contain one or more organic solvents.

[0073] In some embodiments, the aqueous solution SA1 may contain one or more organic solvents.

[0074] The amount of organic solvent may vary depending on the temperature and the amount of ATBS or sodium salt base. This amount is not limited as long as it does not prevent obtaining the aforementioned crystalline form of the sodium salt of ATBS. Methods for determining this limit are well known to those skilled in the art and are common practice. Generally, aqueous solutions or aqueous suspensions SA2 contain more water (by volume) than organic solvent.

[0075] The one or more organic solvents are advantageously selected from the following compounds: - Organic acids, preferably carboxylic acids containing 1 to 8 carbon atoms; - Preferably amides containing 1 to 8 carbon atoms; - Alcohols that preferably contain 1 to 8 carbon atoms; - Preferably ketones containing 3 to 8 carbon atoms; - Ethers, which are advantageously composed of 2 to 8 carbon atoms; - Preferably esters containing 2 to 8 carbon atoms; - Alkanes, preferably containing 4 to 8 carbon atoms, more preferably 5 to 6 carbon atoms; - Preferably halogenated hydrocarbon compounds containing 1 to 8 carbon atoms; - Preferably nitriles containing 1 to 8 carbon atoms; or - These mixtures.

[0076] When an organic solvent is used in the present invention, the temperature can be adjusted so that the solvent-water mixture remains in a liquid state.

[0077] These compounds may be linear or branched. They may be saturated or contain unsaturated bonds. Unsaturated bonds correspond to double or triple bonds (e.g., C=C or C≡C).

[0078] The organic solvent is preferably selected from acrylonitrile, isopropanol, acrylic acid, acetic acid, or a mixture thereof. The organic solvent is preferably acrylonitrile.

[0079] The organic solvent is generally a liquid at the temperature in which steps 2) and 3) are carried out. Furthermore, it is advantageously partially miscible with water, and preferably completely miscible with water.

[0080] The aforementioned organic solvent may, if necessary, be used to solubilize impurities or by-products present with the ATBS used to form the aqueous solution or aqueous suspension SA2. However, ATBS is not necessarily soluble in the aforementioned solvent.

[0081] In preferred embodiments of the present invention, the aqueous solution or aqueous suspension SA2 does not contain an organic solvent.

[0082] In a preferred embodiment of the present invention, the aqueous solution SA1 does not contain an organic solvent.

[0083] The time for mixing the aqueous solution SA1 and the ATBS is advantageously at least 1 minute, preferably 1 to 600 minutes, more preferably 5 to 400 minutes, and even more preferably 10 to 240 minutes.

[0084] The compounds in step 1) can be mixed using a variety of techniques. Examples, but not limited to, include stirrers, loop reactors, static mixers, microreactors, piston reactors, stirred filter dryers such as Nutsche, paddle mixers, double cone mixers, plowshare mixers, and disc mixers.

[0085] The pH in step 1) is advantageously controlled to be 6-14, preferably 8-14, more preferably 10-14, even more preferably 12-14, and even more preferably 13-14.

[0086] The amount of ATBS.Na in the aqueous solution SA2 or aqueous suspension is advantageously 10 to 90% by weight, preferably 20 to 90% by weight, preferably 30 to 90% by weight, preferably 50 to 90% by weight, preferably 20 to 85% by weight, and more preferably 30 to 80% by weight, based on the total weight of the aqueous solution or aqueous suspension SA2.

[0087] Step 2 of the method for producing the crystalline form of ATBS sodium salt): The distillation of the aqueous solution or aqueous suspension SA2 is carried out at a pressure of 700 mbar or less. This distillation is generally carried out in a vacuum distillation apparatus, which is typically an evaporator. Therefore, it is also referred to as "vacuum distillation" in this specification.

[0088] When an aqueous solution or aqueous suspension SA2 is distilled, the formation of the sodium salt of ATBS typically begins by passing it through an evaporator. Thus, ATBS, at least one sodium salt base, and crystalline solid particles of the sodium salt of ATBS coexist in the aqueous solution or aqueous suspension SA2.

[0089] The aqueous solution or aqueous suspension SA2 may be distilled using an evaporator. This may be a falling film evaporator, a rising film evaporator, a scraped thin film evaporator, a short-pass evaporator, a forced-circulation evaporator, a helical tube evaporator, or a flash evaporator. It may also be a continuous stirring reactor. Preferably, the distillation is carried out in a scraped thin film evaporator, a short-pass evaporator, or a forced-circulation evaporator. More preferably, the distillation is carried out in a scraped thin film evaporator.

[0090] Generally, an evaporator is a device that includes an inlet for the solution to be processed (aqueous solution or aqueous suspension SA2), an outlet for discharging the distilled solvent (water and any organic solvent), and an outlet for discharging the suspension S1.

[0091] The residence time of the aqueous solution or aqueous suspension SA2 in a distillation apparatus (preferably under reduced pressure), which is preferably an evaporator, i.e., the distillation time at a pressure of 700 mbar or less, is preferably between 1 second and 600 seconds, preferably between 3 seconds and 300 seconds, and more preferably between 30 seconds and 100 seconds. The residence time corresponds to the time required to carry out step 2), i.e., the time required to produce suspension S1 by distillation of the aqueous solution or aqueous suspension SA2. In other words, if an evaporator is used, it is the residence time of the ATBS (and / or the crystalline form of its sodium salt) between the inlet and outlet of the apparatus. This residence time varies depending on the amount of water (and any organic solvent), ATBS.Na, and sodium salt base present in the aqueous solution or aqueous suspension SA2. To those skilled in the art, methods for adjusting this residence time to obtain the crystalline form of ATBS.Na depending on the amount of components of the aqueous solution or aqueous suspension SA2 are well known.

[0092] The distillation may be carried out in a vertical or horizontal evaporator. Preferably, it is carried out in a vertical evaporator.

[0093] The aqueous solution or aqueous suspension SA2 can be circulated in a parallel or countercurrent flow with respect to the vapor generated by evaporation. Preferably, it is circulated in a countercurrent flow with respect to the vapor in the distillation apparatus. In other words, the aqueous solution or aqueous suspension SA2 is preferably introduced into the distillation apparatus, preferably into the evaporator, in a parallel or countercurrent flow with respect to the distilled solvent.

[0094] The aqueous solution SA2 or aqueous suspension SA2 may be circulated in one or more evaporators in series before obtaining the suspension S1. Preferably, it is circulated in a single evaporator.

[0095] The pressure during distillation is advantageously between 1 and 700 mbar absolute pressure (1 mbar = 100 Pa). It is preferably less than 700 mbar absolute pressure, more preferably less than 600 mbar absolute pressure, more preferably less than 500 mbar absolute pressure, more preferably less than 400 mbar absolute pressure, more preferably less than 300 mbar absolute pressure, more preferably less than 200 mbar absolute pressure, more preferably less than 100 mbar absolute pressure, and even more preferably less than 50 mbar absolute pressure, and advantageously greater than 1 mbar absolute pressure. Absolute pressure corresponds to pressure relative to zero pressure (vacuum).

[0096] Generally, the pressure during distillation is preferably in the range of 10 to 700 mbar, preferably 20 to 700 mbar, preferably 40 to 700 mbar, more preferably 40 to 600 mbar, more preferably 40 to 500 mbar, more preferably 40 to 400 mbar, more preferably 40 to 300 mbar, more preferably 40 to 200 mbar, and more preferably 40 to 100 mbar.

[0097] In a particular embodiment, step 2) includes step 2') (optionally performed) to assist in the evaporation of the solvent. Step 2') consists of raising the temperature of the aqueous solution or aqueous suspension SA2, in other words, the distillation according to step 2') is carried out under heating.

[0098] In some embodiments, in step 2), the aqueous solution or aqueous suspension SA2 is preferably heated to a temperature of 5°C to 95°C, preferably greater than 10°C to 60°C, and more preferably greater than 20°C to 40°C.

[0099] The heating during distillation can be carried out by various techniques. Examples, but not limited to, include heating with steam, heating with hot water, heating with electricity, heating by vapor compression, or heating using a heat pump. Therefore, the distillation apparatus may be a double-walled type in which a high-temperature heat-conducting fluid circulates between two walls.

[0100] The aqueous solution or aqueous suspension SA2 is preferably heated to a temperature of over 5°C to 95°C, preferably over 10°C to 60°C, and more preferably over 20°C to 40°C.

[0101] When the aqueous solution or aqueous suspension SA2 is heated, the temperature is preferably higher than the temperature in step 1).

[0102] The temperature of the aqueous solution or aqueous suspension SA2 is advantageously raised at a gradient of 0.1 to 10°C / hour, preferably 0.2 to 9°C / hour, more preferably 0.3 to 8°C / hour, and even more preferably 0.5 to 5°C / hour.

[0103] In some embodiments, the temperature of the aqueous solution or aqueous suspension SA2 is advantageously raised in a gradient of 10 to 150°C / hour, preferably 30 to 110°C / hour, more preferably 50 to 100°C / hour, and even more preferably 60 to 90°C / hour.

[0104] The temperature rise does not have to be constant throughout the entire process. For example, the aqueous solution or aqueous suspension SA2 may be heated at a rate of 5°C per hour for the first three hours, and then at a rate of 10°C per hour until the final temperature is reached.

[0105] According to another specific embodiment of the present invention, step 2) may include step 2'') (optionally performed) after or instead of step 2'), which helps to increase the productivity and profitability of the method of the present invention by promoting the crystallization of the sodium salt of the ATBS to the crystalline form. Step 2'') consists of lowering the temperature of the aqueous solution or aqueous suspension SA2.

[0106] The aqueous solution or aqueous suspension SA2 is advantageously cooled to a temperature of 5 to less than 95°C, preferably 10 to less than 60°C, more preferably 20 to less than 40°C, and even more preferably 10 to 40°C.

[0107] In some embodiments, step 2) further includes a cooling step.

[0108] The cooling step is advantageously carried out at a temperature of 5°C to 95°C, preferably more than 10°C to 60°C, and more preferably more than 10°C to 40°C.

[0109] In some embodiments, the temperature in the cooling step is reduced in a gradient of 0.1 to 8°C / hour, preferably 0.2 to 8°C / hour, more preferably 0.3 to 8°C / hour, and even more preferably 0.5 to 5°C / hour.

[0110] In some embodiments, the temperature of the cooling step is advantageously lower than the heating temperature of step 2) and / or step 1).

[0111] In some embodiments, the cooling step is performed on an aqueous solution or aqueous suspension SA2, and / or on a concentrated aqueous solution or aqueous suspension SA2, and / or on a suspension S1.

[0112] If the aqueous solution or aqueous suspension SA2 is cooled (step 2''), the temperature is advantageously lower than the temperature in step 2) and step 2') which is performed optionally.

[0113] According to a preferred embodiment, the temperature in step 2'') is the same as or lower than the temperature in step 1).

[0114] In some embodiments, no organic solvent or aqueous solution is added in step 2'' to obtain ATBS.Na crystals.

[0115] The temperature of the aqueous solution or aqueous suspension SA2 is advantageously decreased at a gradient of 0.1 to 8°C / hour, preferably 0.2 to 8°C / hour, more preferably 0.3 to 8°C / hour, and even more preferably 0.5 to 5°C / hour.

[0116] The rate of temperature decrease does not have to be constant throughout the entire process. For example, the aqueous solution or aqueous suspension SA2 may be cooled at a rate of 5°C per hour for the first 3 hours, and then at a rate of 8°C per hour until the final temperature is reached.

[0117] While the aqueous solution or aqueous suspension SA2 is being cooled, crystals of the sodium salt of ATBS are formed, and suspension S1 is obtained.

[0118] In certain embodiments, crystals of a previously obtained sodium salt of ATBS may be added during this step for the purpose of modifying the formation of suspension S1, a process referred to as crystal seeding, which allows for better control of the crystallization temperature, crystal size, particle size distribution, purity of the final product, and possibly yield. Crystals of sodium salt of ATBS added by this method have a powder X-ray diffraction pattern that advantageously includes peaks at positions where 2θ(±0.1°) is 11.7°;12.2°;13.2°;13.5°;15.6°;16.8°;17.8°;18.5°;19.1°;20.6°;21.4°;23.3°;25.1°;25.8°;26.9°;29.1°;29.5°;31.0°;33.0°;33.6°;34.4°;35.2°;35.9°;37.1°;38.4°;39.6°;41.1°;42.9°;45.1°;46.0°;47.2°;47.6°.

[0119] According to a particular embodiment of the present invention, the solvent distilled in step 2) can be partially or entirely recycled to form an aqueous solution SA1 of ATBS in step 1). In other words, the distilled solvent is advantageously at least partially recycled into an aqueous solution SA1 of ATBS.

[0120] According to another specific embodiment of the present invention, the distilled solvent may be partially or entirely recycled, with or without a pretreatment step, in step 4), which is optionally performed, to wash the sodium salt crystals of ATBS obtained after the solid-liquid separation of step 3).

[0121] The resulting suspension S1 advantageously contains 30 to 90% by weight of crystalline ATBS.Na relative to the total weight of the suspension S1. Preferably, it is 50 to 90% by weight, more preferably 30 to 80% by weight, and even more preferably 50 to 60% by weight.

[0122] In step 2), the pH is advantageously greater than 10, preferably greater than 11, more preferably greater than 12, and even more preferably 13-14.

[0123] Step 3 of the method for producing the crystalline form of sodium salt of ATBS): The ATBS.Na crystals contained in the suspension S1 obtained at the end of step 2) are isolated in the solid-liquid separation step and become composition C1.

[0124] The solid-liquid separation step can be carried out using a variety of techniques. Examples, but not limited to, include the use of a centrifuge, decanter, filter press, agitated filter, belt filter, disc filter, or rotary drum filter. The solid-liquid separation is preferably carried out using a centrifuge. The solid-liquid separation may also be carried out by gravity sedimentation.

[0125] Step 3) is advantageously carried out at a temperature of -20 to 40°C, preferably -5 to 30°C.

[0126] After step 3) of solid-liquid separation, the ATBS sodium salt crystals are preferably not dried.

[0127] The content of ATBS sodium salt crystals in the isolated composition C1 is advantageously 40-99% by weight, preferably 60-99% by weight, more preferably 60-98%, and even more preferably 80-99% by weight, relative to the weight of composition C1. The remainder of composition C1 may be water and / or solubilized ATBS sodium salt, and optionally the sodium salt base introduced in step 1).

[0128] After the completion of step 3), the crystal is characterized as a crystal of ATBS sodium salt (ATBS.Na).

[0129] In a particular embodiment, all or part of the liquid phase obtained after the solid-liquid separation is used in the aqueous solution SA1 of step 1).

[0130] In step 4), the pH is advantageously controlled to 6-14, preferably 8-14, more preferably 10-14, even more preferably 12-14, and even more preferably 13-14.

[0131] Step 4 of the method for producing the crystalline form of ATBS.Na): In step 4), which may be performed as desired, composition C1, which contains ATBS.Na crystals obtained at the end of step 3), is washed with a washing solution.

[0132] The washing solution may be water, an aqueous solution of a sodium salt base (which may be saturated or unsaturated), or a solution of ATBS sodium salt (preferably the crystalline form of ATBS.Na) (which may be saturated or unsaturated), and preferably a saturated solution of ATBS.Na.

[0133] Examples of sodium salt solutions include solutions of sodium hydroxide, sodium carbonate, sodium bicarbonate, or mixtures thereof.

[0134] The cleaning solution may contain one or more organic solvents.

[0135] Advantageously, the cleaning solution does not contain organic solvents.

[0136] As already shown in Step 1), the organic solvent is advantageously selected from organic acids, amides, alcohols, ketones, ethers, esters, alkanes, halogenated hydrocarbon compounds, nitriles, or mixtures thereof. The organic solvent is preferably selected from acrylonitrile, isopropanol, acetic acid, or mixtures thereof. More preferably, the organic solvent is acrylonitrile.

[0137] In a particular embodiment, the composition C1 obtained at the end of step 3) is cleaned by spraying a cleaning solution onto the composition C1.

[0138] In a particular embodiment, the composition C1 obtained at the end of step 3) is washed by suspending the composition C1 in the washing solution.

[0139] The weight ratio of the cleaning aqueous solution to composition C1 obtained at the end of step 3) is advantageously 0.05:1 to 10:1, more preferably 0.1:1 to 5:1.

[0140] This washing step is advantageously carried out at a temperature of -5 to 40°C, preferably 0 to 30°C. Those skilled in the art know how to adjust the temperature so as not to solubilize the ATBS.Na crystals.

[0141] The ATBS.Na crystals obtained at the end of step 4), which is performed as desired, can be isolated from the washing solution in the form of composition C2 by a solid-liquid separation step.

[0142] The solid-liquid separation step can be carried out using a variety of techniques. Examples, but not limited to, include the use of vertical or horizontal centrifuges, decanters, filter presses, belt filters, disc filters, push filters, or rotary drum filters. The solid-liquid separation may also be carried out by gravity sedimentation.

[0143] In certain embodiments, all or part of the recovered washing solution may be reused in step 4), with or without the pretreatment step.

[0144] In a particular embodiment, all or part of the recovered washing solution may be used in the aqueous solution SA1 of step 1), with or without a pretreatment step.

[0145] The pH of the washing solution in step 5 is advantageously controlled to 6-14, preferably 8-14.

[0146] Step 5 of the method for producing the crystalline form of ATBS.Na): In step 5), which is performed as desired, composition C1 obtained at the end of step 3) or composition C2 obtained at the end of step 4) is dried.

[0147] The drying step can be carried out using a variety of techniques. Examples, but not limited to, include the use of all convection, conduction, or radiation drying techniques (fluidized bed dryers, through-bed dryers, belt conveyor drying, microwaves, heated agitated filters, high-frequency radiation, infrared radiation, and spraying).

[0148] The drying operation may be carried out under atmospheric pressure, or under reduced pressure.

[0149] The drying step may be carried out discontinuously (batch drying) or continuously.

[0150] Other steps in the method for producing the crystalline form of ATBS.Na: In the process of the above-mentioned manufacturing method, i.e., in steps 1) to 5), and notwithstanding the foregoing steps, at least one polymerization inhibitor may be introduced for the purpose of preventing possible polymerization of ATBS or a salt thereof. This polymerization inhibitor may be selected, not limited to, hydroquinone, paramethoxyphenol, phenothiazine, 2,2,6,6-tetramethyl(piperidine-1-yl)oxyl, 4-hydroxy-2,2,6,6-tetramethyl(piperidine-1-yl)oxyl, phenylenediamine derivatives, or mixtures thereof.

[0151] The polymerization inhibitor is preferably paramethoxyphenol or 4-hydroxy-2,2,6,6-tetramethyl(piperidine-1-yl)oxyl.

[0152] The amount of polymerization inhibitor introduced is advantageously 0.001% to 5% by weight, more preferably 0.01% to 1% by weight, relative to the amount of ATBS introduced in step 1).

[0153] The polymerization inhibitor may be introduced in one or more of the steps of the method. Preferably, an additional amount of the inhibitor is introduced in step 1). More preferably, the polymerization inhibitor is part of the aqueous solution SA1 introduced in step 1).

[0154] The above manufacturing method (steps 1) to 5)) may be carried out continuously or discontinuously (batch manufacturing).

[0155] polymer The present invention also relates to the use of a novel crystalline form of ATBS.Na for the production of polymers.

[0156] Accordingly, the present invention also relates to polymers obtained at least from ATBS that are at least partially present in the crystalline form of ATBS.Na having a powder X-ray diffraction pattern with peaks at 2θ angles of 11,7°;12,2°;13,2°;13,5°;15,6°;16,8°;17,8°;18,5°;19,1°;20,6°;21,4°;23,3°;25,1°;25,8°;26,9°;29,1°;29,5°;31,0°;33,0°;33,6°;34,4°;35,2°;35,9°;37,1°;38,4°;39,6°;41,1°;42,9°;45,1°;46,0°;47,2°;47,6° (±0.1°).

[0157] The polymer is obtained at least partially from the crystalline form of ATBS.Na, and, advantageously, from at least one other monomer selected from hydrophilic nonionic monomers, hydrophilic anionic monomers (different from the crystalline form of ATBS.Na), hydrophilic cationic monomers, hydrophilic zwitterionic monomers, and hydrophobic monomers.

[0158] Therefore, the polymer may be a polymer or homopolymer of multiple different monomers.

[0159] Advantageously, at least 10 mol%, preferably at least 30 mol%, more preferably at least 50 mol%, and even more preferably at least 70 mol%, of the ATBS used to obtain the polymer is the crystalline form of ATBS.Na of the present invention. Even more preferably, 100 mol% of the ATBS is the crystalline form of ATBS.Na of the present invention.

[0160] The polymer preferably contains 1 to 100 mol%, more preferably 2 to 60 mol%, more preferably 3 to 25 mol%, of ATBS, and preferably at least 10 mol%, more preferably at least 30 mol%, more preferably at least 50 mol%, and even more preferably at least 70 mol%, of the crystalline form of ATBS.Na. Even more preferably, 100 mol% of the ATBS used is the crystalline form of ATBS.Na of the present invention.

[0161] In certain embodiments, the polymer advantageously comprises at least 10 mol%, preferably at least 20 mol%, more preferably at least 30 mol%, more preferably at least 40 mol%, more preferably at least 50 mol%, more preferably at least 60 mol%, more preferably at least 70 mol%, more preferably at least 80 mol%, and more preferably at least 90 mol%, and advantageously at least 10 mol%, preferably at least 30 mol%, more preferably at least 50 mol%, and even more preferably at least 70 mol%, the crystalline form of ATBS.Na of the present invention, and even more preferably 100% of the ATBS used is the crystalline form of ATBS.Na of the present invention.

[0162] In certain embodiments, the polymer is a homopolymer of ATBS, and advantageously, at least 10 mol%, preferably at least 30 mol%, more preferably at least 50 mol%, and even more preferably at least 70 mol%, is the crystalline form of ATBS.Na, and even more preferably, 100% of the ATBS used is the crystalline form of ATBS.Na of the present invention.

[0163] In a particular embodiment, the polymer is a homopolymer of the crystalline form of ATBS.Na.

[0164] In a particular embodiment, the polymer is a polymer obtained from ATBS (at least 10 mol% of which is preferably the crystalline form of ATBS.Na) and at least one nonionic monomer.

[0165] Polymer composition The polymer is obtained from the crystalline form of ATBS.Na, and, advantageously, from at least one other monomer that can be selected from hydrophilic nonionic monomers, and / or hydrophilic anionic monomers, and / or hydrophilic cationic monomers, and / or hydrophilic zwitterionic monomers, and / or hydrophobic monomers, and mixtures thereof. The polymer may be a polymer or homopolymer of a plurality of different monomers.

[0166] Advantageously, the hydrophilic nonionic monomers that can be used in the present invention include, in particular, acrylamide, methacrylamide, N-alkylacrylamide, N-alkylmethacrylamide, N,N-dialkylacrylamide (e.g., N,N-dimethylacrylamide or N,N-diethylacrylamide), N,N-dialkylmethacrylamide, alkoxylated esters of acrylic acid, alkoxylated esters of methacrylic acid, N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylformamide (NVF), and N-vinylacetamide. The water-soluble vinyl monomer is selected from the group including N-vinylimidazole, N-vinylsuccinimide, acryloylmorpholine (ACMO), glycidyl methacrylate, glyceryl methacrylate, vinyl acetate, diacetone acrylamide, methacrylic anhydride, acrylonitrile, maleic anhydride, itaconamide, hydroxyalkyl (meth)acrylate, aminoalkyl (meth)acrylate, thioalkyl (meth)acrylate, hydroxyalkyl acrylate, hydroxyalkyl methacrylate, and mixtures thereof. Among the nonionic monomers, the alkyl group is preferably C1-C5, and more preferably C1-C3. The alkyl group is preferably a linear alkyl group. Preferably, the hydrophilic nonionic monomer is acrylamide.

[0167] The polymer preferably contains 0 to 99 mol%, preferably 40 to 98 mol%, and more preferably 75 to 97 mol%, of hydrophilic nonionic monomers.

[0168] Advantageously, apart from the crystalline form of ATBS.Na, the hydrophilic anionic monomers that can be used in the present invention can be selected from a large group. These monomers may have a vinyl functional group (preferably acrylic, malee, fuma, malon, itacone, or allyl) and may contain a carboxylic acid group, a phosphonic acid group, a phosphoric acid group, a sulfate group, or a sulfonic acid group, or another anionic charged group. Examples of suitable monomers include acrylic acid; methacrylic acid; dimethylacrylic acid; itaconic acid; C1-C3 hemiesters of itaconic acid, crotonic acid; maleic acid; fumaric acid; acryloyl chloride, 3-acrylamido-3-methylbutanoic acid; maleic anhydride; and strong acid monomers having a sulfonic acid functional group or a phosphonic acid functional group, such as vinyl sulfonic acid, vinyl phosphonic acid, allyl sulfonic acid, methallyl sulfonic acid, 2-methylidenepropane-1,3-disulfonic acid, 2-sulfoethyl methacrylate, and sulfopropyl methacrylate. Examples include sulfopropyl acrylate, allylphosphonic acid, styrenesulfonic acid, ethylene glycol methacrylate phosphate, 2-acrylamido-2-methylpropanesulfonic acid (ATBS), 2-acrylamido-2-methylpropanedisulfonic acid, 3-allyloxy-2-hydroxypropanesulfonic acid, diethylallylphosphonate, etc.; water-soluble salts of these monomers, such as alkali metal salts (different from the crystalline form of ATBS.Na), alkaline earth metal salts, or ammonium salts; and mixtures thereof. Preferably, the hydrophilic anionic monomer is acrylic acid and / or a salt thereof.

[0169] The polymer advantageously contains 0 to 99 mol%, preferably 5 to 70 mol%, and more preferably 10 to 50 mol%, of hydrophilic anionic monomers (different from the crystalline form of ATBS.Na). Above 5 mol%, these proportions also include monomers of the crystalline form of ATBS.Na according to the present invention.

[0170] In certain embodiments, the hydrophilic anionic monomer, other than the crystalline form of ATBS.Na, may be salinated.

[0171] According to the present inventors, chlorination refers to the -R of the anionic monomer. a The proton of at least one acidic functional group of the (=O)-OH type (in this case R represents P, S, or C) is replaced with a metal cation or an ammonium cation, -R a This means forming a (=O)-OX type salt (where X is a metal cation or an organic cation). In other words, the non-chlorinated form is the acidic form of the monomer, for example, in the case of a carboxylic acid functional group, R b -C(=O)-OH corresponds to the above monomer, while the chloride form of the monomer is R b -C(=O)-O - X + This corresponds to the form of X + This corresponds to an alkali cation or an organic cation. The chlorination of the acidic functional group of the branched-chain water-soluble polymer may be partial or whole. The chlorination form is advantageously equivalent to a salt of an alkali metal (Li, Na, K, etc.), an alkaline earth metal (Ca, Mg, etc.), or an ammonium (e.g., ammonium ion or tertiary ammonium). A preferred salt is a sodium salt.

[0172] The aforementioned chlorination may be carried out before, during, or after polymerization.

[0173] In certain embodiments, the polymer advantageously comprises 1 to 100 mol%, preferably 50 to 100 mol%, of hydrophilic anionic monomers in chloride form. These proportions include monomers in crystalline form of ATBS.Na according to the present invention.

[0174] Advantageously, the hydrophilic cationic monomers that can be used in the present invention are selected from monomers derived from vinyl-type units (preferably acrylamide, acrylic, allyl, or malein), and these monomers have a phosphonium or quaternary ammonium functional group. Particularly, and without limitation, these may be mentioned: diallyldialkylammonium salts such as diallyldimethylammonium chloride (DADMAC); acidified or quaternary salts of dialkylaminoalkyl (meth)acrylamide, e.g., methacrylamide-propyltrimethylammonium chloride (MAPTAC), acrylamide-propyltrimethylammonium chloride (APTAC); acidified or quaternary salts of dialkylaminoalkyl acrylates such as quaternary or chlorinated dimethylaminoethyl acrylate (DMAEA); quaternary or chlorinated dimethylaminoethyl These include acidified or quaternized salts of dialkylaminoalkyl methacrylates such as DMAEMA; acidified or quaternized salts of N,N-dimethylallylamine; acidified or quaternized salts of diallylmethylamine; acidified or quaternized salts of diallylamine; polyvinylamines resulting from the hydrolysis (basic or acidic) of an amide group -N(R2)-CO-R1 (where R1 and R2 are independently hydrogen atoms or alkylated chains having 1 to 6 carbon atoms), such as polyvinylamines obtained from the hydrolysis of polyvinylformamide; polyvinylamines obtained by Hoffmann decomposition; and mixtures thereof. Advantageously, the alkyl group is C1 to C7, preferably C1 to C3, and may be linear, cyclic, saturated, or unsaturated. Preferably, it is quaternized dimethylaminoethyl acrylate.

[0175] Methods for preparing quaternized monomers, such as using an RX-type quaternizing agent in which R is an alkyl group and X is a halogen or sulfate, are well known to those skilled in the art.

[0176] The term "quaternary amine" refers to a molecule that can alkylate a tertiary amine.

[0177] The quaternizing agent may be selected from dialkyl sulfates containing 1 to 6 carbon atoms or alkyl halides containing 1 to 6 carbon atoms. Preferably, the quaternizing agent is selected from methyl chloride, benzyl chloride, dimethyl sulfate, or diethyl sulfate.

[0178] In addition, the present invention also includes DADMAC, APTAC, and MAPTAC monomers in which the counterion is a sulfate ion, fluoride ion, bromide ion, or iodide ion instead of a chloride ion.

[0179] The polymer preferably contains 0 to 20 mol%, more preferably 0 to 6 mol%, of hydrophilic cationic monomers.

[0180] Advantageously, the hydrophilic zwitterionic monomer may be a derivative of a vinyl-type unit (preferably acrylamide, acrylic, allyl, or malein), the monomer having a quaternary amine or ammonium functional group and a carboxylic acid (or carboxylate), sulfonic acid (or sulfonate), or phosphoric acid (or phosphate) functional group. In particular, and without limitation, may be mentioned, 2-((2-(acryloyloxy)ethyl)dimethylammonio)dimethylammonio)ethane-1-sulfonate, 3-((2-(acryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate, 4-((2-(acryloyloxy)ethyl)dimethylammonio)butane-1-sulfonate, [2-(acryloyloxy)ethyl](dimethylammonio)acetate Dimethylaminoethyl acrylate derivatives such as 2-((2-(methacryloyloxy)ethyl)dimethylammonio)ethane-1-sulfonate, 3-((2-(methacryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate, 4-((2-(methacryloyloxy)ethyl)dimethylammonio)butane-1-sulfonate, and [2-(methacryloyloxy)ethyl](dimethylammonio)acetate. Dimethylaminopropylacrylamide derivatives such as noethyl methacrylate derivatives, 2-((3-acrylamidopropyl)dimethylammonio)ethane-1-sulfonate, 3-((3-acrylamidopropyl)dimethylammonio)propane-1-sulfonate, 4-((3-acrylamidopropyl)dimethylammonio)butane-1-sulfonate, [3-(acryloyloxy)propyl](dimethylammonio)acetate, 2-((3-methacrylamidopropyl)dimethylammonio)ethane-1-sulfonate, 3-((3-methacrylamidopropyl)dimethylammonio)propane-1-sulfonate, 4-((3-methacrylamidopropyl)dimethylammonio)butane-1-sulfonate, and [3-(methacryloyloxy)propyl](dimethylammonio)acetate, as well as mixtures thereof.

[0181] Other hydrophilic zwitterionic monomers, particularly those described by the applicant in International Publication No. 2021 / 123599, may also be used.

[0182] The polymer preferably contains 0 to 20 mol%, more preferably 0 to 10 mol%, of a hydrophilic zwitterionic monomer.

[0183] Distribution coefficient K ow Hydrophobic monomers with a value greater than 1 can also be used in the production of polymers according to the present invention. These are preferably selected from the following list: (i) C4~C 30 Alkyl chain, or (ii) arylalkyl (C4~C 30 Alkyl, C4~C 30 (iii) Aryl) chain, or (iv) Propoxylated chain, or (v) Ethoxylated chain, or (v) (meth)acrylic acid ester with ethoxylated and propoxylated chains; Alkylaryl sulfonate (C4~C 30 Alkyl, C4~C 30 Ariel); (i) C4~C 30 Alkyl chain, or (ii) arylalkyl (C4~C 30 Alkyl, C4~C 30 (iii) a propoxylated chain, or (iv) an ethoxylated chain, or (v) a monosubstituted or disubstituted (meth)acrylamide having an aryl chain, or a propoxylated chain; anionic or cationic monomer derivatives of (meth)acrylamide or (meth)acrylic acid having a hydrophobic chain; N-vinylpyridine, and mixtures thereof. The hydrophobic monomer may contain a halogen atom, such as chlorine.

[0184] Among these hydrophobic monomers: -The alkyl group is preferably C4~C 20 And more preferably C4~C8. C6~C 20 Alkyl groups are preferably linear, while C4-C5 alkyl groups are preferably branched. - The arylalkyl group is preferably C7~C 25And more preferably C7~C 15 That is the case. - The ethoxylated chain preferably contains 1 to 200, preferably 6 to 100, and more preferably 10 to 40 -CH2-CH2-O- groups. - The propoxylated chain preferably contains 1 to 50, more preferably 1 to 20 -CH2-CH2-CH2-O- groups.

[0185] Preferred hydrophobic monomers belonging to these classes include, for example, the following: - n-hexyl(meth)acrylate, n-octyl(meth)acrylate, octyl(meth)acrylamide, lauryl(meth)acrylate, lauryl(meth)acrylamide, myristyl(meth)acrylate, myristyl(meth)acrylamide, pentadecyl(meth)acrylate, pentadecyl(meth)acrylamide, cetyl(meth)acrylate, cetyl(meth)acrylamide, oleyl(meth)acrylate, oleyl(meth)acrylamide, erucyl(meth)acrylate, erucyl(meth)acrylamide, N-tert-butyl(meth)acrylamide, 2-ethylhexylacrylate, C4~C 22 Itaconic acid hemiester, C4~C 22 Acidified or quaternary salts of dialkylaminoalkyl (meth)acrylates, C4~C 22 Acidified or quaternized salts of dialkylaminoalkyl(meth)acrylamide, vinylpyridine, acrylamide undecanoic acid, and mixtures thereof. - Cationic allyl derivatives of formula (I) or (II):

[0186] [ka]

[0187] During the ceremony: R: Independently, an alkyl chain containing 1 to 4 carbon atoms; R1: Alkyl or arylalkyl chain containing 8 to 30 carbon atoms; X: A halide selected from the group consisting of bromides, chlorides, iodides, and fluorides, and any negatively charged counterion; Furthermore, preferably, a (meth)acryloyl-type hydrophobic cationic derivative corresponding to formula (III):

[0188] [ka]

[0189] During the ceremony: - A represents O or N-R5 (preferably, A represents N-R5). - R2, R3, R4, R5, R6, R7: Independently, alkyl chains containing hydrogen or 1 to 4 carbon atoms. - Q: An alkyl chain containing 1 to 20 carbon atoms, - R8: Alkyl or arylalkyl chain containing 8 to 30 carbon atoms, - X: A halide selected from the group consisting of bromides, chlorides, iodides, and fluorides, and any negatively charged counterion.

[0190] If the polymer is water-soluble, it is advantageous that it contains less than 5 mol% of hydrophobic monomers, the amount of which is adjusted so that the polymer maintains its water solubility.

[0191] In the present invention, monomers having fluorescent functional groups may be used. Monomers having fluorescent functional groups can be detected by any suitable method, such as fluorescence photometry using a fixed-wavelength fluorometer. Generally, monomers having fluorescent functional groups are detected at excitation and emission maxima, which can be identified using a scanning fluorometer.

[0192] Monomers having fluorescent functional groups are selected from, for example, the following monomers: sodium or potassium styrenesulfonate, styrenesulfonic acid, vinylimidazole and its derivatives, 9-vinylanthracene and its derivatives, N-9-xanthenylacrylamide and its derivatives, allyldibenzosverenol and its derivatives, cinconicin and its derivatives, quininone and its derivatives, cinconinone and its derivatives, N,N-dimethyl-N-[3-[N'-(4-methoxynaphthalimide)]]propyl-N-(2-hydroxy-3-allyloxy)propylammonium hydroxide, and mixtures thereof.

[0193] When functionalized with allyl, vinyl, or acrylic double bonds, other fluorescent compounds can be used, such as pyranine and its derivatives, coumarin and its derivatives, quinolaxin and its derivatives, pinacyanol and its derivatives, xanthohydrol and its derivatives, dabusil and its derivatives, 3-hydroxy-2-methylene-3-(1-naphthyl)propionic acid and its derivatives, rhodamine and its derivatives, N-dibenzoberylacrylamide and its derivatives, naphthalene derivatives, fluorescein and its derivatives, pyrene and its derivatives, carbostyryl and its derivatives, pyrazoline and its derivatives, and mixtures thereof.

[0194] In a preferred embodiment, the polymer does not contain monomers having fluorescent functional groups.

[0195] In certain embodiments, the polymer may comprise at least one cyclic monomer having a hydrolyzable functional group. Advantageously, the cyclic monomer having a hydrolyzable functional group, or the cyclic monomer itself, may be selected from cyclic ketene acetals, thionolactones, and mixtures thereof.

[0196] The cyclic ketene acetal is advantageously selected from 2-methylene-1,3-dioxepane (MDO), 5,6-benzo-2-methylene-1,3-dioxepane (BMDO), 2-methylene-4-phenyl-1,3-dioxolane (MPDL), 2-methylene-1,3,6-trioxocan (MTC), and mixtures thereof. Preferably, it is 2-methylene-1,3-dioxepane (MDO).

[0197] The thionolactone is advantageously selected from dibenzo[c,e]oxepin(7H)-5-thion (DOT), ε-thionocaprolactone, 3,3-dimethyl-2,3-dihydro-5H-benzo[e][1,4]dioxepin-5-thion (DBT), and mixtures thereof. Preferably, it is 3,3-dimethyl-2,3-dihydro-5H-benzo[e][1,4]dioxepin-5-thion.

[0198] In certain embodiments, the polymer may comprise at least one group having an LCST.

[0199] According to the general knowledge of those skilled in the art, a group having an LCST corresponds to a group whose water solubility at a given concentration is modified above a certain temperature and depending on the salt concentration. This is a group that has a heating transition temperature that determines its lack of affinity to the solvent. This lack of affinity to the solvent results in opacity or loss of transparency, which can be due to precipitation, aggregation, gelation, or viscosity increase of the medium. The lowest transition temperature is known as the LCST (lower critical solution temperature). At each concentration of a group having an LCST, a heating transition temperature is observed. It is higher than the LCST, which is the minimum point on the curve. Below this temperature, the polymer is soluble in water, and above this temperature, the polymer loses its solubility in water.

[0200] In a particular embodiment, the polymer may comprise at least one group having UCST.

[0201] According to the general knowledge of those skilled in the art, a group having UCST corresponds to a group whose water solubility at a given concentration is modified below a certain temperature and depending on the salt concentration. This is a group that has a cooling transition temperature that determines the lack of affinity with the solvent. The lack of affinity with the solvent results in opacity or loss of transparency, which can be due to precipitation, aggregation, gelation, or viscosity increase of the medium. The highest transition temperature is known as UCST (upper critical solution temperature). At each concentration of a group having UCST, a cooling transition temperature is observed. It is lower than the UCST, which is the maximum point on the curve. Above this temperature, the polymer is soluble in water, and below this temperature, the polymer loses its solubility in water.

[0202] The amounts of different monomers can be adjusted by those skilled in the art so as not to exceed 100 mol% when producing the polymer according to the present invention.

[0203] According to the present invention, the polymer may have a linear, branched, crosslinked, star-shaped, or comb-shaped structure. This structure can be obtained, according to the general knowledge of those skilled in the art, for example, by selecting initiators, transfer agents, polymerization techniques such as reversible addition-cleavage chain transfer (RAFT) polymerization, nitroxide-mediated polymerization (NMP), or atom transfer radical polymerization (ATRP), incorporating structural monomers, or selecting concentrations.

[0204] The polymer may be further structured with a crosslinking agent. A structured polymer is a non-linear polymer having side chains such that, when dissolved in water, the polymer exhibits a high degree of entanglement, resulting in very high low-gradient viscosities.

[0205] The aforementioned crosslinking agent is advantageous in that, - A structural agent may be selected from the group including polyethylene unsaturated monomers (having at least two unsaturated functional groups), vinyl functional groups, particularly allyl functional groups or acrylic functional groups, for example, methylenebisacrylamide (MBA), triallylamine, or tetraallylammonium chloride, or 1,2-dihydroxyethylenebis-(N-acrylamide). - A monomer having at least two epoxy functional groups - A monomer having at least one unsaturated and one epoxy functional group, - Transport agents such as polyperoxides, polyazoids, and polymercaptant polymers, as well as macroinitiators such as polyols. - Functionalized polysaccharides, - A water-soluble metal composite consisting of the following: * Examples include, but are not limited to, metals with a valency greater than 3, such as aluminum, boron, zirconium, or titanium, and * Ligands having a hydroxyl functional group, Selected from.

[0206] The amount of branching agent in the polymer is advantageously less than 40,000 ppm by weight, preferably less than 10,000 ppm by weight, and more preferably less than 5,000 ppm by weight, relative to the total weight of the monomers of the polymer.

[0207] In a particular embodiment, the amount of branching agent is equal to at least 0.1 ppm by weight, preferably at least 1 ppm by weight, more preferably at least 10 ppm by weight, more preferably at least 100 ppm by weight, and even more preferably at least 1000 ppm by weight, relative to the total weight of the polymer monomer.

[0208] The polymer is water-soluble, and when it contains a branching agent, the polymer remains water-soluble. Those skilled in the art are well aware of the method for adjusting the amount of the branching agent and, in some cases, the amount of the chain transfer agent required to obtain this result.

[0209] In a preferred embodiment, the polymer is a water-soluble polymer that does not contain a branching agent.

[0210] In certain embodiments, the polymer may contain a chain transfer agent.

[0211] The chain transfer agent is preferably methanol; isopropyl alcohol; sodium hypophosphite; calcium hypophosphite; magnesium hypophosphite; potassium hypophosphite; ammonium hypophosphite; formic acid; sodium formate; calcium formate; magnesium formate; potassium formate; ammonium formate; 2-mercaptoethanol; 3-mercaptopropanol; dithiopropylene glycol; thioglycerol; thioglycolic acid; thiohydracrylic acid; thiolactic acid; thiomalic acid; cysteine; aminoethanethiol; thioglycolate; allyl phosphite; allyl mercaptan such as n-dodecyl mercaptan; sodium methallysulfonate; calcium methallysulfonate; magnesium methallysulfonate; potassium methallysulfonate; ammonium methallysulfonate; trialkyl (C 12 ~C 15 ) phosphite, alkyl phosphite such as dioleyl hydrogen phosphite, dibutyl phosphite; dialkyl dithiophosphate such as dioctyl phosphonate; tertiary nonyl mercaptan; 2-ethylhexyl thioglycolate; n-octyl mercaptan; n-dodecyl mercaptan; tertiary dodecyl mercaptan; iso-octyl thioglycolate; 2-ethylhexyl thioglycolate; 2-ethylhexyl mercaptoacetate; polythiol; and mixtures thereof. Preferably, the chain transfer agent is sodium hypophosphite or sodium formate.

[0212] The amount of the transfer agent in the polymer is advantageously 0 to 100,000 ppm by weight, preferably 0 to 10,000 ppm by weight, more preferably 0 to 1,000 ppm by weight, and even more preferably 0 to 100 ppm by weight, relative to the total weight of the monomers of the polymer. If present, the transfer agent corresponds to at least 0.1 ppm by weight, preferably at least 1 ppm by weight, relative to the total weight of the monomers of the polymer.

[0213] In certain embodiments, the polymer does not contain a transfer agent.

[0214] Generally speaking, the polymer does not require the development of any specific polymerization method. In fact, it may be obtained using any polymerization technique well known to those skilled in the art. These include solution polymerization; gel polymerization; precipitation polymerization; emulsion polymerization (aqueous or reversed phase); suspension polymerization; reactive extrusion polymerization; water-in-water polymerization; or micelle polymerization.

[0215] The polymerization described above is generally radical polymerization, preferably by reverse-phase emulsion polymerization or gel polymerization. Radical polymerization includes free radical polymerization using UV initiators, azo initiators, redox initiators, or thermal initiators, as well as controlled radical polymerization (CRP) or matrix polymerization techniques.

[0216] Controlled radical polymerization technologies are not limited to, but include iodine transfer polymerization (ITP), nitroxide-mediated polymerization (NMP), atom transfer radical polymerization (ATRP), reversible addition-cleavage chain transfer (RAFT) polymerization including MADIX (Macromolecular Design by Interchange of Xanthates) technology, various modifications of organometallic radical polymerization (OMRP), and organic heteroatom-mediated radical polymerization (OHRP).

[0217] The polymer may be partially or completely hydrolyzed after treatment.

[0218] The post-hydrolysis treatment is a hydrolysis reaction of the polymer after the polymer has been formed by the polymerization of the monomers. This step involves reacting the hydrolyzable functional groups of the monomer, preferably nonionic functional groups, and more preferably amide or ester functional groups, with a hydrolyzing agent. This hydrolyzing agent may be, for example, an enzyme, an ion exchange resin, or a Brønsted metal acid (e.g., a hydrohalic acid) or a Brønsted base (e.g., an alkali metal hydroxide or alkaline earth metal hydroxide). Preferably, the hydrolyzing agent is a Brønsted base. In the process of this post-hydrolysis treatment of the polymer, the number of carboxylic acid functional groups increases. In fact, carboxylate groups are generated by the reaction of the base with the amide or ester functional groups present in the polymer.

[0219] If the production of the polymer includes a drying step such as spray drying, drum drying, microwave drying, or drying in a fluidized bed, the polymer may be in the form of a liquid, gel, or solid.

[0220] The polymer advantageously has a molecular weight of at least 500,000 g / mol, preferably 500,000 to 40 million g / mol, and more preferably 5 million to 30 million g / mol. The molecular weight is determined by the weight-average molecular weight. The polymer may also have a molecular weight of 5,000 to 100,000 g / mol or 100,000 to 500,000 g / mol.

[0221] The molecular weight is determined by the intrinsic viscosity of the polymer. The intrinsic viscosity may be measured by methods known to those skilled in the art, and can be calculated from reduced viscosity values ​​for different polymer concentrations by a graphing method, which involves plotting the reduced viscosity value (y-axis) against the concentration (x-axis) and extrapolating the curve to zero concentration. The intrinsic viscosity value is plotted on the y-axis, or the least squares method is used. Subsequently, the molecular weight can be determined using the Mark-Houwink formula: [η]=KM α In the formula, [η] represents the intrinsic viscosity of the polymer as determined by the solution viscosity method. K represents the experimental constant. M represents the molecular weight of the polymer. α represents the Mark-Houwink coefficient. K and α vary depending on the specific polymer-solvent system.

[0222] Use of polymers Another aspect of the present invention relates to the use of a polymer obtained from the crystalline form of ATBS.Na.

[0223] The present invention also relates to the use of this polymer in well drilling or cementing; conformance, diversion; open, closed, or semi-closed circuit water treatment; fermentation broth treatment; sludge treatment; construction; paper or cardboard manufacturing; batteries; wood processing; hydraulic composition (concrete, cement, mortar, and aggregates); cosmetic preparation; detergent preparation; textile manufacturing; geothermal energy; diaper manufacturing; or agriculture.

[0224] The present invention also relates to the use of this polymer as a coagulant, binder, absorbent, water remover, filler retainer, dehydrating agent, conditioning agent, stabilizer, fixative, film-forming agent, sizing agent, superplasticizing agent, clay inhibitor or dispersant.

[0225] The present invention and its advantages will be better understood by referring to the following figures and examples provided to illustrate the invention in a non-limiting manner. [Brief explanation of the drawing]

[0226] [Figure 1] Figure 1 shows the proton NMR spectrum of ATBS obtained according to Example 1. [Figure 2]Figure 2 shows the proton NMR spectrum of the ATBS sodium salt (ATBS.Na) crystals obtained according to Example 2a. [Figure 3] Figure 3 shows the X-ray diffraction pattern of ATBS obtained according to Example 1. [Figure 4] Figure 4 shows the X-ray diffraction pattern of the ATBS.Na crystals obtained according to Example 2a. [Figure 5] Figure 5 shows the Fourier transform infrared spectrum of ATBS obtained according to Example 1. [Figure 6] Figure 6 shows the Fourier transform infrared spectrum of the ATBS.Na crystals obtained according to Example 2a. [Figure 7] Figure 7 shows the thermogram of ATBS obtained according to Example 1. [Figure 8] Figure 8 shows the thermogram of the ATBS.Na crystals obtained according to Example 2a. [Figure 9] Figure 9 shows the particle size distribution of ATBS obtained according to Example 1. [Figure 10] Figure 10 shows the particle size distribution of the ATBS.Na crystals obtained according to Example 2a. [Figure 11] Figure 11 shows the optical microscope image of ATBS obtained according to Example 1. [Figure 12a] Figure 12a shows the optical microscope image of the ATBS.Na crystals obtained according to Example 2a. [Figure 12b] Figure 12b shows the optical microscope image of the ATBS.Na crystals obtained according to Example 2b. [Figure 12c] Figure 12c shows the optical microscope image of the ATBS.Na crystals obtained according to Example 2c. [Figure 13] Figure 13 shows the corrosion effect of ATBS used in the acid form (Example 1) or as the sodium salt crystals (Example 2a) on carbon steel plates. [Figure 14] Figure 14 shows a photograph of the ATBS.Na product obtained in solution according to Comparative Example 2b (according to U.S. Patent No. 6331647 (Example 27)). [Figure 15] Figure 15 shows an optical microscope image of ATBS.Na crystals obtained according to Comparative Example 2c (according to International Publication No. 2013 / 079507 (Example 3)). [Figure 16] Figure 16 shows an optical microscope image of the ATBS.Na crystal obtained according to Comparative Example 2d. [Figure 17] Figure 17 shows an optical microscope image of the ATBS.Na crystal obtained according to Comparative Example 2e. [Examples]

[0227] AM = Acrylamide A = Acrylic acid DMEA.MeCl = Dimethylaminoethyl methacrylate methyl chloride

[0228] Example 1: 2-Acrylamido-2-methylpropanesulfonic acid (ATBS) (A H ) synthesis 1522 g of acrylonitrile containing 0.4 wt% water is added to a 2000 ml reactor with a stirrer and double jacket, the mixture is stirred for 1 hour, and the temperature of the sulfonated mixture is maintained at -20°C by cooling with the double jacket of the reactor, and then 180 g of fuming sulfuric acid (18% oleum) with a H2SO4 titer of 104% is added.

[0229] 97 g of isobutylene is added to the sulfonated mixture at a rate of 1.6 g / min.

[0230] When adding isobutylene, the temperature of the mixture is controlled to 45°C. 2-acrylamido-2-methylpropanesulfonic acid particles precipitate from the mixture, and the solid content is approximately 20% by weight. The reaction mixture is filtered through a Buchner funnel and dried under reduced pressure at 50°C. The resulting solid is 2-acrylamido-2-methylpropanesulfonic acid (ATBS A H It is in the form of a very fine white powder.

[0231] Observation with an optical microscope (Figure 11) was performed using ATBS A HThis indicates that the crystals have a needle-like shape.

[0232] Example 2a: 2-acrylamido-2-methylpropanesulfonate sodium salt (ATBS,Na A Na 2a) Formation of the aforementioned crystal form (the present invention) Add 439 g of 22% (by weight in water) sodium hydroxide aqueous solution to a 1000 ml reactor with a stirrer and double jacket. Add 452 g of ATBS A from Example 1. H Add this to the mixture mentioned earlier.

[0233] The mixture is stirred at 10°C for 30 minutes to form an aqueous solution SA2.

[0234] The aqueous solution SA2 is heated to 40°C under reduced pressure of 50 mbar for 20 minutes, then maintained at the same temperature under reduced pressure of 50 mbar for 30 minutes, and cooled to 10°C. The cooling time from 40°C to 10°C is 6 hours. A suspension S1 of ATBS.Na crystals is obtained. The suspension S1 is filtered using a Robatel vertical centrifuge. ATBS.Na A Na A solid of composition C1 containing 80% by weight of crystals of 2a is obtained.

[0235] Observation with an optical microscope (Figure 12a) shows crystal A Na This indicates that 2a has both cylindrical and plate-like forms.

[0236] Example 2b: ATBS sodium salt (ATBS.Na A Na 2b) Formation of the crystal form Except for distilling SA2 under 700 mbar, follow the procedure described in Example 2a to obtain ATBS.Na A Na Prepare crystal 2b.

[0237] Optical microscope observation (Figure 12b) shows crystal A obtained under these conditions. Na 2b is ATBS.Na A prepared in Example 2a. Na This indicates that it is identical to crystal 2a.

[0238] Example 2c: ATBS sodium salt (ATBS.Na A Na Formation of the crystal form in 2c) Except for shortening the cooling time to 3 hours and 45 minutes, the procedure described in Example 2a is followed, and ATBS.Na A Na Prepare 2c crystals.

[0239] Optical microscopy observation (Figure 12c) shows that the crystals obtained under these conditions are ATBS.Na A Na This indicates that it is identical to crystal 2a.

[0240] Comparative Example 2a: Preparation of ATBS.Na crystals under atmospheric pressure (1 bar) (CE-A Na 2a) (Not obtained) The reaction is carried out according to the procedure described in Example 2a, except that SA2 is distilled under atmospheric pressure.

[0241] At the end of the cooling step, the aqueous solution SA2 does not form a suspension S1, making it impossible to perform filtration or centrifugation to isolate the ATBS sodium salt crystals.

[0242] Comparative Example 2b: Preparation of ATBS sodium salt (CE-A Na 2b) (Not obtained) The reaction was carried out according to the conditions described in Example 27 of U.S. Patent No. 6,331,647. Add 124 g of sodium hydroxide and 0.13 g of hydroquinone monomethyl ether to a 5000 ml reactor with a double jacket and a stirrer containing 400 g of water. Stir the medium until all of the sodium hydroxide is dissolved.

[0243] 632g ATBS A H Add the above mixture. Stir the mixture at 10°C for 30 minutes to form an aqueous solution of the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid.

[0244] The resulting aqueous solution is filtered into a 3000 ml reactor equipped with an air purge tube and fitted with a distillation apparatus. The contents are heated and stirred while air is blown in below the water surface at 0.5 cubic feet per hour. The contents are heated to 50°C under reduced pressure of 933 mbar (approximately 700 milliliters of mercury). Once the water is removed, a yellowish, honey-like product is formed. The product is then transferred to a Robatel vertical centrifuge, but no solid was recovered.

[0245] Since a solid sample could not be obtained, observation using an optical microscope was not possible (Figure 14).

[0246] Comparative Example 2c: Preparation of ATBS sodium salt (CE-A Na 2c) (Not obtained) The reaction was carried out according to the conditions described in Example 3 of the International Patent Application Publication No. 2013079507.

[0247] 100 g of ATBS.Na solution (16.77 wt%) is obtained according to Example 1 of International Publication No. 2013079507.

[0248] From the aforementioned ATBS.Na solution, 50 g of solvent (a mixture of acrylonitrile and methanol) is removed under reduced pressure (less than 700 mbar) at room temperature while introducing air into the ATBS.Na solution. ATBS.Na CE-A Na The 2c solid is obtained, filtered, washed with acrylonitrile / methanol, and then dried overnight at 50°C.

[0249] Optical microscopy observation (Figure 15) shows ATBS.Na CE-A Na This indicates that the dried solid of 2c does not correspond to the ATBS.Na crystals according to the present invention.

[0250] Comparative example 2d: ATBS.Na CE-A Na Preparation of 2d (not according to the present invention) The reaction is carried out according to the procedure described in Example 2a, except that SA2 is distilled under 720 mbar.

[0251] ATBS.Na CE-A Na A solid of composition C1 containing 80% by weight of 2d crystals is obtained.

[0252] Optical microscopy observation (Figure 16) shows ATBS.Na CE-A Na This indicates that the 2d crystal does not correspond to the ATBS.Na crystal according to the present invention.

[0253] Comparative example 2e: ATBS.Na CE-A Na Preparation of 2e (not according to the present invention) The reaction is carried out according to the procedure described in Example 2a, except that the cooling time is set to 3 hours and 20 minutes.

[0254] ATBS.Na CE-A Na A solid of composition C1 containing 80% by weight of 2e crystals is obtained.

[0255] Optical microscopy observation (Figure 17) shows ATBS.Na CE-A Na This indicates that the 2e crystal does not correspond to the ATBS.Na crystal according to the present invention.

[0256] Example 3: ATBS A from Examples 1 and 2a H and ATBS.Na A Na NMR analysis of the 2a product ATBS A H and ATBS.Na A Na 2a is analyzed by proton nuclear magnetic resonance (NMR).

[0257] The sample is dissolved in D2O. The NMR spectrometer is a Bruker model with a frequency of 400 MHz and a 5 mm BBO BB- 1 H is attached.

[0258] The two proton spectra (Figures 1 and 2) are similar, and the peak assignments are consistent with the molecular structure of ATBS or its sodium salt.

[0259] Example 4: ATBS A from Examples 1 and 2aH and ATBS.Na A Na Analysis of the 2a product by X-ray diffraction ATBS A H and ATBS.Na A Na The crystals of 2a are pre-ground to form a powder and analyzed by X-ray diffraction over an angular range of 10° to 90°. The apparatus used is a Rigaku MiniFlex II diffractometer equipped with a copper X-ray source.

[0260] ATBS.Na A Na The crystals of 2a (Figure 4) exhibit an X-ray diffraction pattern with characteristic peaks at positions where the 2θ angle (±0.1°) is 11.7°; 12.2°; 13.2°; 13.5°; 15.6°; 16.8°; 17.8°; 18.5°; 19.1°; 20.6°; 21.4°; 23.3°; 25.1°; 25.8°; 26.9°; 29.1°; 29.5°; 31.0°; 33.0°; 33.6°; 34.4°; 35.2°; 35.9°; 37.1°; 38.4°; 39.6°; 41.1°; 42.9°; 45.1°; 46.0°; 47.2°; 47.6°.

[0261] ATBS A H The same peaks are not seen in the X-ray diffraction pattern of (Figure 3).

[0262] Example 5: ATBS A H and ATBS.Na A Na Fourier transform infrared measurement of 2a The apparatus used for Fourier transform infrared measurement is a Perkin Elmer Spectrum 100 with an accuracy of 8 cm equipped with a single reflection ATR polarization accessory -1

[0263] ATBS A H and ATBS.Na A Na The crystals of 2a are sieved through a 100 μm sieve. The particles remaining on the sieve are dried and placed in an oven at 60°C for at least 4 hours.

[0264] ​Place several hundred milligrams of solid on the diamond of the ATR accessory and manually apply pressure using the accessory.

[0265] The following bands (Figure 6) are characteristic of the crystalline form of ATBS sodium salt A Na of 2a: 3576 cm -1 3485 cm -1 3310 cm -1 3079 cm -1 2975 cm -1 1658 cm -1 1629 cm -1 1543 cm -1 1403 cm -1 1321 cm -1 1301 cm -1 1205 cm -1 1187 cm -1 1163 cm -1 1046 cm -1 980 cm -1 629 cm -1 .

[0266] ATBS A H does not show the same peaks in its infrared spectrum (Figure 5).

[0267] Example 6: ATBS A from Examples 1 and 2a H and ATBS.Na A Na 2a product differential scanning calorimetry (DSC) The apparatus used is a Mettler DSC3.

[0268] ATBS A H and ATBS.Na A Na 2a crystals are analyzed under a nitrogen stream with a heating gradient of 10 °C / min. The initial temperature is 30 °C and the product is heated to 350 °C.

[0269] ATBS A HThe thermogram (Figure 7) shows a thermal effect at 195.15°C, which is generally considered to be the melting / decomposition point of ATBS, followed by two exothermic decomposition phenomena at 212.8°C and 288.4°C.

[0270] ATBS.Na A Na The thermogram of crystal 2a (Figure 8) shows four thermal phenomena at 49.8°C; 144.8°C; 169.8°C; and 254.3°C.

[0271] Example 7: ATBS A from Examples 1 and 2a H and ATBS.Na A Na Measurement of the minimum ignition energy (MIE) of the 2a product The minimum ignition energy is measured according to the NF EN 13821 standard.

[0272] The explosion force meter is a vertical Hartmann tube. The dust dispersion system is mushroom-shaped.

[0273] The total induction is less than 25 microhenries. The discharge voltage is 5kV to 15kV. The electrodes are made of brass and spaced at a minimum distance of 6mm.

[0274] Tests were conducted with different energies and dispersion masses, and the results are summarized in the table below.

[0275] ATBS.Na A Na In the aforementioned crystalline form of 2a, needle-shaped ATBS A H It is clear that the risk of explosion is significantly lower than that.

[0276] [Table 1]

[0277] [Table 2]

[0278] Example 8: ATBS A from Examples 1 and 2aH and ATBS.Na A Na 2K A K Particle size measurement of product 2a ATBS A H and ATBS.Na A Na The crystals of 2a are analyzed using laser diffraction to determine their particle size distribution.

[0279] The laser diffraction apparatus used is the Cilas 1190.

[0280] ATBS A H d of the crystal 50 The value is approximately 40 μm, and 90% of the particles are smaller than 100 μm (Figure 9).

[0281] ATBS.Na A Na d of crystal 2a 50 The value is approximately 600 μm, and 90% of the particles are smaller than approximately 1500 μm (Figure 10). ATBS.Na A Na The amount of particles smaller than 325 μm in the crystal of 2a is less than 10%.

[0282] Example 9: Evaluation of the corrosiveness of different forms of ATBS against carbon steel ATBS A H , A Na 2a, and ATBS CE-A Na 20g each of 2c to 2e, 20 x 50mm 2 The material is deposited onto two carbon steel plates of the specified dimensions. The coated plates are placed in a 50°C oven for 15 days. At the same time, an uncoated control plate is placed under the same temperature conditions.

[0283] A photograph of the plate in this condition (Figure 13) shows ATBS.Na A Na Compared to crystal 2a, ATBS A H The plate that was in contact with the material shows visually more pronounced corrosion. These observations are confirmed by weighing the plate before and after the contact period.

[0284] Solid ATBS sodium salt CE-A Na Tests 2c to 2e were also conducted. The results are shown in Table 3.

[0285] [Table 3]

[0286] Example 10a: ATBS.Na A Na Preparation of solution 2a 1000g ATBS.Na A Na The crystalline form of 2a and 1000 g of water are introduced into a 2000 ml double-jacketed reactor equipped with a condenser, pH meter, and stirrer. The pH of the mixture is greater than 12.

[0287] The resulting mixture is an aqueous solution of ATBS.Na at a concentration of 50% by weight.

[0288] Example 10b: ATBS.Na CE-A Na Preparation of solution 2c Crystal ATBS.Na CE-A Na The same protocol as in Example 10a is reproduced, except for the use of 2c.

[0289] Example 10c: ATBS.Na CE-A Na Preparation of 2d solution Crystal ATBS.Na CE-A Na The same protocol as in Example 10a is reproduced, except for the use of 2d.

[0290] Example 10d: ATBS.Na CE-A Na Preparation of solution 2e Crystal ATBS.Na CE-A Na The same protocol as in Example 10a is reproduced, except for the use of 2e.

[0291] Example 11: Acid A H Preparation of a solution of ATBS.Na 800g ATBS A HThe mixture and 650g of water are introduced into a 2000ml double-jacketed reactor equipped with a condenser, pH meter, and stirrer. The pH of the mixture is less than 1.

[0292] Prepare a 50% by weight sodium hydroxide aqueous solution using a dropping funnel. Add this caustic solution to the reaction mixture over a period of 120 minutes. Maintain a temperature below 30°C.

[0293] The final pH of the aforementioned solution is 8-10.

[0294] Add 310 g of 50 wt% sodium hydroxide aqueous solution.

[0295] The resulting mixture is an aqueous solution of ATBS sodium salt at a concentration of 50% by weight.

[0296] Example 12: Effect of ATBS morphology and structure on preservation 500 g of 50% (by weight in water) aqueous solutions of ATBS.Na prepared according to Examples 10a-10d and 11 were stored for 12 months to compare their stability over time by measuring and monitoring the appearance of ATBS.Na homopolymers.

[0297] In parallel, ATBS (Acid A) in different solid forms H or sodium salt A Na The stability of 2a) was also evaluated over the same period.

[0298] In this case, every three months, A H , A Na 2a, and CE-A Na Using the stored ATBS products from 2c to 2e, a fresh 500 g ATBS.Na solution was prepared according to the preparation process described in Example 10a or 11.

[0299] The stability of the solid product was also evaluated by monitoring the amount of ATBS.Na homopolymer present after that time.

[0300] The aforementioned solution was analyzed by liquid-phase steric exclusion chromatography using an Agilent 1260 chromatograph equipped with Aquagel-OH 20, 30, 40, and 50 columns capable of analyzing anionic polymers up to 600,000 g / mol of PEG equivalent.

[0301] The aforementioned ATBS.Na solution was diluted to 2000 ppm (by weight in water) before injection. The UV signal at 250 nm at the column outlet was integrated with respect to the polymer peak, and the results are detailed in Tables 4a and 4b below. A larger signal area indicates a higher polymer abundance and, therefore, lower product stability over time.

[0302] [Table 4a]

[0303] [Table 4b]

[0304] These results demonstrate that the crystalline form of ATBS.Na of the present invention exhibits improved stability during storage, whether stored as a solid or in solution.

[0305] Example 13: Polymer P1-A of AM / ATBS (75 / 25 mol%) Na Preparation of 2a 628.3g of deionized water, 500g of 50% (by weight in water) acrylamide solution, 16.2g of urea, and 268.8g of ATBS.Na A Na Add the crystals from 2a to a 2000 ml beaker.

[0306] The resulting solution is cooled to 0-5°C, transferred to an adiabatic polymerization reactor, and bubbled with nitrogen for 30 minutes to remove all trace amounts of dissolved oxygen.

[0307] Next, - 0.75 g of 2,2'-azobisisobutyronitrile, - 1.5 ml of 5 g / L solution (in water) of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, - 1.5 ml of 3 g / L solution of sodium hypophosphate (in water), - 2.25 ml of 1 g / L solution of tert-butyl hydroperoxide (in water), - 2.25 ml of a 1 g / L solution of ammonium iron(II) sulfate (Mohr's salt) in water. The following is added to the reactor.

[0308] After a few minutes, the nitrogen inlet is shut off and the reactor is closed. The polymerization reaction is carried out for 1 to 5 hours until the temperature reaches its peak. The resulting rubbery gel is cut into particles with a particle size of 1 to 6 mm.

[0309] Next, the gel is dried and pulverized to obtain polymer P1-A in powder form. Na We obtain 2a.

[0310] Example 14: Preparation of comparative polymer P1 of AM / ATBS (75 / 25 mol%) Add 535.1g of deionized water to a 2000ml beaker, cool the solution to 5°C, and add 243.0g of ATBS A H Add the crystals.

[0311] Prepare a 93.90 g 50% (by weight in water) sodium hydroxide solution using a dropping funnel. Immediately after the crystals have completely dissolved, add the caustic solution to the reaction mixture over 120 minutes. Maintain the temperature below 30°C. The final pH of the solution should be 8-10.

[0312] The mixture was completed by adding 500g of 50% (by weight in water) acrylamide solution and 16.2g of urea.

[0313] The resulting solution is cooled to 0-5°C, transferred to an adiabatic polymerization reactor, and bubbled with nitrogen for 30 minutes to remove all trace amounts of dissolved oxygen.

[0314] Next, - 0.75 g of 2,2'-azobisisobutyronitrile, - 1.5 ml of 5 g / L solution (in water) of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, - 1.5 ml of 3 g / L solution of sodium hypophosphate (in water), - 2.25 ml of 1 g / L solution of tert-butyl hydroperoxide (in water), - 2.25 ml of a 1 g / L solution of ammonium iron(II) sulfate (Mohr's salt) in water. The following is added to the reactor.

[0315] After a few minutes, the nitrogen inlet is shut off and the reactor is closed. The polymerization reaction is carried out for 1 to 5 hours until the temperature reaches its peak. The resulting rubbery gel is cut into particles with a particle size of 1 to 6 mm.

[0316] Next, the gel is dried and pulverized to obtain polymer P1-A in powder form. H To obtain.

[0317] ATBS.Na CE-A Na Except for using 2c, the same protocol as in Example 13 was reproduced, and polymer P1-CEA Na Generate 2c.

[0318] ATBS.Na CE-A Na The same protocol as in Example 13 was reproduced, except for the use of 2d, and polymer P1-CEA Na Generate a 2D object.

[0319] ATBS.Na CE-A Na The same protocol as in Example 13 was reproduced except for the use of 2e, and polymer P1-CEA Na Generate 2e.

[0320] Example 15: ATBS.Na A Na Homopolymer P2-A of 2a Na Preparation of 2a 562.1g of deionized water and 389.4g of ATBS.Na A Na Add the crystals from 2a to a 2000 ml beaker.

[0321] The resulting solution is cooled to 5-10°C, transferred to an adiabatic polymerization reactor, and bubbled with nitrogen for 30 minutes to remove all trace amounts of dissolved oxygen.

[0322] Next, - 0.45 g of 2,2'-azobisisobutyronitrile, - 1.5 ml of a 2.5 g / L solution (in water) of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, - 1.5 ml of 1 g / L solution of sodium hypophosphate (in water), - 1.5 ml of 1 g / L solution of tert-butyl hydroperoxide (in water), - Add 1.5 ml of a 1 g / L solution of ammonium iron(II) sulfate (Mohr's salt) in water to the reactor.

[0323] After a few minutes, the nitrogen inlet is shut off and the reactor is closed. The polymerization reaction is carried out for 2 to 5 hours until the temperature reaches its peak. The resulting rubbery gel is cut and dried to obtain a coarse powder, which is then pulverized and sieved to obtain polymer P2-A in powder form. Na We obtain 2a.

[0324] Example 16: Preparation of comparative homopolymer P2 of ATBS Add 427.5g of deionized water to a 2000ml beaker, cool the solution to 5°C, and add 352.1g of ATBS A while stirring. H Add the crystals.

[0325] Prepare a 136.1 g 50% (by weight in water) sodium hydroxide solution using a dropping funnel. Add this caustic solution to the reaction mixture over 120 minutes. Maintain a temperature below 30°C. The final pH of the solution should be 8-10.

[0326] The resulting solution is cooled to 5-10°C, transferred to an adiabatic polymerization reactor, and bubbled with nitrogen for 30 minutes to remove all trace amounts of dissolved oxygen.

[0327] Next, - 0.45 g of 2,2'-azobisisobutyronitrile, - 1.5 ml of a 2.5 g / L solution (in water) of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, - 1.5 ml of 1 g / L solution of sodium hypophosphate (in water), - 1.5 ml of 1 g / L solution of tert-butyl hydroperoxide (in water), - 1.5 ml of a 1 g / L solution of ammonium iron(II) sulfate (Mohr's salt) in water. Add the following to the reactor:

[0328] After a few minutes, the nitrogen inlet is shut off and the reactor is closed. The polymerization reaction is carried out for 2 to 5 hours until the temperature reaches its peak. The resulting rubbery gel is cut and dried to obtain a coarse powder, which is then pulverized and sieved to obtain polymer P2-A in powder form. H To obtain.

[0329] ATBS.Na CE-A Na Except for using 2c, the same protocol as in Example 15 was reproduced to produce polymer P2-CEA Na Generate 2c.

[0330] ATBS.Na CE-A Na Except for using 2d, the same protocol as in Example 15 was reproduced, and polymer P2-CEA Na Generate a 2D object.

[0331] ATBS.Na CE-A Na Except for using 2e, the same protocol as in Example 15 was reproduced, and polymer P2-CEA Na Generate 2e.

[0332] Example 16a: Preparation of polymer P3 of AM / AA / ATBS (75 / 10 / 15 mol%)

[0333] Different monomer amounts, copolymer P3-A Na The experimental protocol of Example 14 is reproduced, except that the acrylamide / acrylic acid / ATBS in 2a is adjusted to achieve the desired molar composition.

[0334] Polymer P3-A H , ATBS A H Prepare using [this method].

[0335] Polymer P3-CEA Na 2c is ATBS.Na CE-A Na Prepare using 2c.

[0336] Polymer P3-CEA Na 2d is ATBS.Na CE-A Na Prepare using 2d.

[0337] Polymer P3-CEA Na 2e is ATBS.Na CE-A Na Prepare using 2e.

[0338] Example 16b: Preparation of polymer P4 of AM / DMEA.MeCl / ATBS (60 / 5 / 35 mol%) Polymer P4-A Na 2a, P'4-A H P4-CEA Na 2c, P4-CEA Na 2d, and P4-CEA Na Prepare 2e according to the preparation process described in Example 16a.

[0339] Example 16c: Preparation of polymer P5 of AM / DADMAC / ATBS (75 / 5 / 20 mol%) Polymer P5-A Na 2a, P5-A H P5-CEA Na 2c, P5-CEA Na 2d, and P5-CEA Na Prepare 2e according to the preparation process described in Example 16a.

[0340] Example 17: Viscosity measurement of polymers P1-P5 The reduced viscosity of the polymers prepared in Examples 13 to 16 was measured at 25°C in a 0.5 M sodium chloride aqueous solution using a Brookfield LVT viscometer fitted with a UL adapter at 60 rpm.

[0341] Preparation of polymer solutions: Dissolve 500 mg of dry polymer in a beaker containing 290 ml of deionized water at a stirring speed of 500 rpm. Add 9.75 g of sodium chloride to the prepared solution. The solution is stirred at 700 rpm for 10 minutes to completely dissolve the salt. The prepared solution is filtered through a 200 μm mesh. Transfer 16 ml of the prepared solution to a cylindrical tube and use it to perform viscosity measurement.

[0342] [Table 5]

[0343] Polymers containing the novel crystalline form of ATBS.Na have a higher viscosity than polymers prepared from conventional forms of ATBS.Na or obtained from other crystalline forms.

Claims

1. A crystalline form of sodium 2-acrylamido-2-methylpropanesulfonate, ATBS.Na, having a powder X-ray diffraction pattern that includes peaks at positions where the 2θ angle (±0.1°) is 11.7°; 12.2°; 13.2°; 13.5°; 15.6°; 16.8°; 17.8°; 18.5°; 19.1°; 20.6°; 21.4°; 23.3°; 25.1°; 25.8°; 26.9°; 29.1°; 29.5°; 31.0°; 33.0°; 33.6°; 34.4°; 35.2°; 35.9°; 37.1°; 38.4°; 39.6°; 41.1°; 42.9°; 45.1°; 46.0°; 47.2°; 47.6°.

2. 3576 cm －１ 、3485 cm －１ 、3310 cm －１ 、3079 cm －１ 、2975 cm －１ 、1658 cm －１ 、1629 cm －１ 、1543 cm －１ 、1403 cm －１ 、1321 cm －１ 、1301 cm －１ 、1205 cm －１ 、1187 cm －１ 、1163 cm －１ 、1046 cm －１ 、980 cm －１ 、629 cm －１ (±8 cm －１ ) having a Fourier transform infrared spectrum including peaks at, the crystalline form of ATBS.Na according to claim 1.

3. A crystalline form of the sodium salt of ATBS.Na according to claim 1 or claim 2, characterized by having a minimum ignition energy of more than 500 mJ.

4. The crystalline form of ATBS.Na according to any one of claims 1 to 3, characterized by exhibiting four thermal phenomena at 49.8°C; 144.8°C; 169.8°C and 254.3°C (±10°C) by differential scanning calorimetry.

5. A method for producing the crystalline form of the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid, ATBS.Na, according to any one of claims 1 to 4, comprising at least the following sequential steps: 1) Aqueous solution or aqueous suspension SA ２ To form 2-acrylamido-2-methylpropanesulfonic acid, aqueous solution SA １ and the step of mixing with at least one sodium salt base; 2) Suspension S １ To form the aqueous solution or aqueous suspension SA ２ The step of distilling at a pressure of 700 mbar or less; 3) The suspension S １ The solid-liquid is separated, and the suspension S obtained at the end of step 2) is obtained. １ The crystals of composition C １ A step of isolating it in that form.

6. The aqueous solution or aqueous suspension SA ２ The amount of ATBS.Na in the aqueous solution or aqueous suspension SA ２ The method according to claim 5, characterized in that it is 10 to 90% by weight of the total weight.

7. Step 2) In the aqueous solution or aqueous suspension SA ２ The method according to claim 5 or claim 6, characterized in that the material is heated, preferably at a temperature of 5°C to 95°C.

8. The method according to any one of claims 5 to 7, characterized in that step 2) further comprises a cooling step, preferably carried out at a temperature of 5°C to 95°C.

9. The method according to any one of claims 5 to 8, characterized in that the temperature of the cooling step is reduced in a gradient of 0.1 to 8°C / hour.

10. The suspension S １ However, the suspension S １ The method according to any one of claims 5 to 9, characterized in that it contains 30 to 90% by weight of ATBS.Na crystalline form based on the total weight.

11. The method according to any one of claims 5 to 10, characterized in that the sodium salt is selected from sodium hydroxide, sodium carbonate, sodium bicarbonate, and mixtures thereof.

12. A polymer at least partially obtained from the crystalline form of ATBS.Na, the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid, having a powder X-ray diffraction pattern that includes peaks at positions where the 2θ angle (±0.1°) is 11.7°; 12.2°; 13.2°; 13.5°; 15.6°; 16.8°; 17.8°; 18.5°; 19.1°; 20.6°; 21.4°; 23.3°; 25.1°; 25.8°; 26.9°; 29.1°; 29.5°; 31.0°; 33.0°; 33.6°; 34.4°; 35.2°; 35.9°; 37.1°; 38.4°; 39.6°; 41.1°; 42.9°; 45.1°; 46.0°; 47.2°; 47.6°.

13. The polymer according to claim 12, characterized in that it is obtained at least partially from the crystalline form of ATBS.Na, and from at least one other monomer selected from hydrophilic nonionic monomers, hydrophilic anionic monomers, hydrophilic cationic monomers, hydrophilic zwitterionic monomers, and hydrophobic monomers.

14. Use of the polymer according to claim 12 or 13 in any application selected from well drilling; well cementing; conformance, diversion; open, closed, or semi-closed circuit water treatment; fermentation broth treatment; sludge treatment; construction; paper or cardboard manufacturing; batteries; wood treatment; hydraulic composition treatment; cosmetic preparation; detergent preparation; textile manufacturing; geothermal energy; diaper manufacturing; or agriculture.

15. Use of the polymer according to claim 12 or claim 13 as a coagulant, binder, absorbent, water remover, filler retainer, dehydrating agent, conditioning agent, stabilizer, fixative, film-forming agent, sizing agent, superplasticizing agent, clay inhibitor, or clay dispersant.

Images