Novel Polymer and Method for Producing the Same

Abstract

The present invention relates to a novel water-soluble dialdehyde-functionalized polymer, a process for its preparation and its use, in particular for applications in the field of the manufacture of paper or cardboard.

Description

Technical Field

[0001] The present invention relates to novel water-soluble dialdehyde-functionalized (advantageously glyoxal-functionalized) polymers, a method for producing the same, and use thereof, particularly for applications in the field of the production of paper or cardboard.

Background Art

[0002] In the paper industry, there is always a demand for improvement of the manufacturing methods for paper or cardboard, especially with regard to cost reduction, yield, productivity, and further final product characteristics.

[0003] Water-soluble dialdehyde-functionalized polyacrylamides are widely used in the manufacturing method of paper, particularly to improve the dry strength of these papers. These water-soluble polyacrylamides are mainly made from nonionic, cationic, anionic, or amphoteric polymers called base polymers, to which dialdehyde is reacted.

[0004] Document US20110056640 describes a method for manufacturing paper that realizes a compound obtained from the reaction of a dialdehyde-functionalized one with an acrylamide / diallyldimethylammonium chloride copolymer. This method only improves drainage.

[0005] Document FR2987375 of the present applicant is an improved method for manufacturing paper that includes a base copolymer containing a polyfunctional compound incorporated during the polymerization of the base copolymer monomer, and its reaction with a dialdehyde. By incorporating the polyfunctional compound, it is possible to improve the dry strength and drainage performance of the paper.

[0006] Document US20170247489 is a method for manufacturing paper that uses a terpolymer obtained by copolymerizing a base polymer with glyoxal, wherein the base polymer is obtained by copolymerizing a primary amide-containing monomer and a cationic monomer.

[0007] Document US10,730,989 relates to a method for producing a (meth)acrylamide copolymer-based papermaking additive.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Non-Patent Documents

[0009]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] Currently, the dialdehyde process (especially glyoxalation) has two main problems.

[0011] The first problem is that commercially available dialdehyde-functionalized (especially glyoxal-functionalized) polyacrylamide products contain a large number of unreacted amide groups, which may react with dialdehyde (especially glyoxal) during storage, leading to continuous cross-linking of the base polyacrylamide molecules and reducing the product's shelf life. In addition, in practice, polyacrylamide contains a relatively small amount, generally less than about 5 mol percent, of ionic monomers, which limits the contribution of the ionic charges of these polymers.

[0012] The second problem relates to the acid treatment used to stop the reaction between the dialdehyde and the base polymer, which is associated with a significant decrease in the viscosity of the polymer aqueous solution. The polymer thus obtained exhibits reduced application performance.

Means for Solving the Problems

[0013] The applicant has surprisingly discovered that the synthesis of a polymer according to a specific method enables an increase in its molecular weight without affecting its viscosity. This increase in the base polymer molecular weight gives the paper improved application performance from the perspective of dry strength compared to existing prior art solutions, improves drainage, and thus enables an increase in the speed of the paper machine, and therefore, productivity is also expected to improve.

[0014] The use of the polymer obtained from the present invention is part of the general principle of improving product performance, more specifically, dry strength and drainage characteristics. The better performance of the polymer according to the present invention enables a reduction in the amount of the product required for application, and therefore, this encompasses reducing greenhouse gas emissions such as carbon dioxide associated with the production and use of synthetic polymers.

[0015] The present invention relates to a water-soluble dialdehyde-functionalized polymer, - at least one cationic or anionic monomer A, and - at least one nonionic monomer B, - At least one structuring system, (i) Different from at least one monomer A, at least one compound I selected from allylsulfonic acid, methallylsulfonic acid, allyldisulfonic acid, methallyldisulfonic acid, salts thereof, and mixtures thereof, and (ii) Different from at least one monomer B, of formula (1)

[0016] [Chemical formula]

[0017] [wherein, R1 and R2 are each independently of the other a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, or a CH2-OH group, [wherein, R1 and R2 are not both hydrogen atoms at the same time (when R2 = H, R1 ≠ H; when R1 = H, R2 ≠ H)] at least one compound II comprising at least one structuring system, and - Optionally, at least one zwitterionic or hydrophobic monomer C, and - Optionally, at least one crosslinking agent, and - Optionally, at least one migrating agent relates to a water-soluble dialdehyde-functionalized polymer.

[0018] This water-soluble dialdehyde-functionalized polymer comprises the following steps: a) The step of forming a solution (S1) comprising at least a first fraction (F1) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II, b) The polymerization 1 (PO1) step of fraction F1 to form a solution of the first gradient polymer (PG1), c) The step of adding a second fraction (F2) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II to the solution containing PG1, d) Step of polymerization 2 (PO2) of fraction F2 to PG1 to form a solution of the second gradient polymer (PG2), and e) Step of adding a third fraction (F3) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II to a solution containing PG2, and f) Step of polymerization 3 (PO3) of fraction F3 to PG2 to form a solution containing the base polymer, and g) Step of diluting the solution containing the base polymer and reacting at least one dialdehyde (preferably glyoxal) with the base polymer to obtain a water-soluble dialdehyde-functionalized polymer (preferably glyoxalated), obtained according to at least one of fraction F1, F2, or F3 contains at least one monomer A, at least one of fraction F1, F2, or F3 contains at least one monomer B, at least one of fraction F1, F2, or F3 contains at least one compound I, at least one of fraction F1, F2, or F3 contains at least one compound II.

[0019] Monomer A is either only cationic or only anionic. It is not a mixture of cationic and anionic monomers.

[0020] When monomer A is anionic, the water-soluble dialdehyde-functionalized polymer does not contain cationic monomers.

[0021] When monomer A is cationic, the water-soluble dialdehyde-functionalized polymer does not contain anionic monomers except for compound I.

[0022] The present invention also relates to a production method for this water-soluble dialdehyde-functionalized polymer (preferably glyoxalated).

[0023] The present invention also relates to a method for manufacturing paper or cardboard, which realizes this water-soluble dialdehyde-functionalized polymer (advantageously, glyoxalated).

[0024] The present invention also relates to the use of this water-soluble dialdehyde-functionalized polymer (advantageously, glyoxal-functionalized) in the recovery of hydrocarbons (oil and / or gas); in the drilling or cementing of wells (especially hydrocarbon wells); in the stimulation of hydrocarbon wells (oil and / or gas), for example, in hydraulic fracturing, conditioning, conversion; in the water treatment of open, closed, or semi-closed circulation; in the treatment of fermentation must; in the treatment of sludge; in construction; in the treatment of timber; in the treatment of hydraulic compositions (concrete, cement, mortar, and aggregates); in mining; in the formulation of cosmetics; in the formulation of detergents; in textile manufacturing; in the geothermal sector; in the manufacture of sanitary napkins; or in agriculture.

[0025] The present invention also relates to the use of the polymer according to the present invention as a flocculant, coagulant, binder, fixing agent, viscosity reducer, thickener, absorbent, anti-friction agent, drainage agent, charge-holding agent, dehydrating agent, conditioning agent, stabilizer, fixing agent, film-forming agent, sizing agent, superplasticizer agent, clay inhibitor, or dispersant.

Embodiments for Carrying Out the Invention

[0026] "Polymer" is used to designate a copolymer produced using a structured system comprising at least two different monomers, namely at least one monomer A (cationic or anionic) and at least one non-ionic monomer B, as well as at least one compound I and at least one compound II. Optionally, it may include at least one zwitterionic monomer and / or one hydrophobic monomer and / or a cross-linking agent and / or a migrating agent.

[0027] A water-soluble polymer means a polymer that, when dissolved at a concentration of 10 g / l in deionized water with stirring at 25 °C, results in an aqueous solution free of insoluble particles. -1

[0028] In the present invention, the first and second gradient polymers are prepolymers.

[0029] Throughout this specification, the viscosity is measured at 25 °C in an aqueous solution using a Brookfield viscometer.

[0030] In this specification, it is considered that a person skilled in the art can determine a suitable speed according to the Brookfield viscometer module and the viscosity range to be measured. In practice, this type of measurement is part of the general knowledge of a person skilled in the art.

[0031] "X and / or Y" according to the present invention designates "X" or "Y", or "X and Y".

[0032] All possible combinations between the various disclosed embodiments, whether these are preferred embodiments or embodiments given by way of example, are equally part of the present invention. In addition, when ranges of values are given, these ranges include the end point values. This disclosure also includes all combinations between the end point values and these ranges of values. For example, the range of values "1 to 20, preferably 5 to 15" includes the ranges "1 to 5", "1 to 15", "5 to 20", and "15 to 20", and the disclosure of the values 1, 5, 15, and 20.

[0033] Hereinafter, before undergoing the reaction with a dialdehyde (advantageously glyoxal) according to step g), the water-soluble base polymer obtained by the method of the present invention is referred to as the base polymer.

[0034] Water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) The present invention relates to a water-soluble dialdehyde-functionalized polymer (advantageously, glyoxalated), which is characterized by the method of obtaining it.

[0035] The water-soluble dialdehyde-functionalized polymer (advantageously, glyoxalated) according to the present invention is - at least one monomer A which is cationic or anionic, and - at least one non-ionic monomer B, and - (i) at least one compound I selected from allyl sulfonic acid, methallyl sulfonic acid, allyl disulfonic acid, methallyl disulfonic acid, salts thereof, and mixtures thereof, which is different from at least one monomer A, and (ii) at least one compound II of formula (1) which is different from at least one monomer B

[0036] [Chemical formula]

[0037] [R1 and R2 are independently of each other a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, or a CH2-OH group, wherein R1 and R2 are not both hydrogen atoms at the same time (when R2 = H, R1 ≠ H; when R1 = H, R2 ≠ H)] and at least one structured system containing at least one compound II and - at least one dialdehyde, advantageously glyoxal, and - optionally, at least one zwitterionic or hydrophobic monomer C, and - optionally, at least one crosslinking agent, and - optionally, at least one migrating agent (advantageously, composed of them).

[0038] Monomer A is either only cationic or only anionic. It is not a mixture of cationic and anionic monomers.

[0039] When monomer A is anionic, the water-soluble dialdehyde-functionalized polymer does not contain a cationic monomer.

[0040] When monomer A is cationic, the water-soluble dialdehyde-functionalized polymer does not contain an anionic monomer except for Compound I.

[0041] Monomer composition Monomer A The water-soluble dialdehyde-functionalized polymer according to the invention (advantageously glyoxalated) is a synthetic polymer. It may contain one or more cationic monomers, or one or more anionic monomers (designated "monomer A").

[0042] Advantageously, the cationic monomer A may in particular be selected from vinyl-type monomers, preferably acrylamide, acrylic, allyl, or maleic having an ammonium functional group, advantageously quaternary ammonium. In particular, but not limited to, the following may be mentioned: dimethylaminoethyl acrylate quaternized (DMAEA), dimethylaminoethyl methacrylate (DMAEMA), diallyldimethylammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (APTAC), and methacrylamidopropyltrimethylammonium chloride (MAPTAC), and mixtures thereof. Preferably, it is diallyldimethylammonium chloride (DADMAC).

[0043] The water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) advantageously contains from 1 to 60 mol%, preferably from 3 to 40 mol%, more preferably from 4 to 30 mol% of the cationic monomer A, and the remaining monomers constituting the water-soluble dialdehyde-functionalized polymer to reach 100 mol% are selected from monomer B and / or monomer C, preferably from monomer B.

[0044] Those skilled in the art know, for example, a method for producing a quaternized monomer by an alkyl halide of the R-X type (where R is an alkyl group (preferably C1-C3) and X is a halogen (R-X may particularly be methyl chloride)). In addition, the present invention also includes DADMAC, APTAC, and MAPTAC type monomers in which the halide counterion is fluoride, bromide, or iodide instead of chloride.

[0045] Advantageously, the anionic monomer A may be selected from a large group. These monomers may have a vinyl type functional group, particularly an acrylic, maleic, fumaric, malonic, itaconic, or allyl functional group. They may also contain a carboxylic acid group, phosphonic acid group, phosphoric acid group, sulfonic acid group, or another group having an anionic charge. Preferred monomers belonging to this class are, for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, acrylamidoundecanoic acid, 3-acrylamido-3-methylbutanoic acid, maleic anhydride, 2-acrylamido-2-methylpropanesulfonic acid (ATBS), vinylsulfonic acid, vinylphosphonic acid, 2-sulfoethyl methacrylate, sulfopropyl methacrylate, sulfopropyl acrylate, allylphosphonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanedisulfonic acid, their salts, and their mixtures. Preferably, it is acrylic acid or itaconic acid, and even more preferably, acrylic acid.

[0046] Thus, in a particular embodiment of the present invention, the anionic monomer may be chlorinated.

[0047] Being chlorinated means that the proton substitution of at least one acid functional group of the anionic monomer A of the -R(O)-OH type (where R = P, S, or C) is replaced by a metal cation to form a salt of the -R(O)-OX type (where X is a metal cation). In other words, the non-chlorinated form corresponds to the acid form of the monomer, for example, R-C(=O)-OH in the case of a carboxylic acid functional group, while the chlorinated form of the monomer corresponds to the R-C(=O)-O-X+ form, where X+ corresponds to an alkali cation. The chlorination of the acid functional groups of the water-soluble dialdehyde-functionalized polymer can be partial or total.

[0048] The chlorinated form preferably corresponds to an alkali metal salt (Li, Na, K...), an alkaline earth metal salt (Ca, Mg...), or an ammonium salt (e.g., ammonium ion or tertiary ammonium). A preferred salt is the sodium salt.

[0049] Chlorination can be carried out before or after polymerization.

[0050] The water-soluble dialdehyde-functionalized anionic polymer (preferably being glyoxalated) preferably contains anionic monomer A in the range of 1 to 99 mol%, preferably in the range of 2 to 70 mol%, more preferably in the range of 3 to 50 mol%, and even more preferably in the range of 5 to 35 mol%. The remaining monomers constituting the water-soluble dialdehyde-functionalized polymer to reach 100 mol% are selected from monomer B and / or monomer C, preferably from monomer B.

[0051] In a particular embodiment of the present invention, when the anionic monomer A is 2-acrylamido-2-methylpropanesulfonic acid (ATBS), it is in its hydrated form. The hydrated form is a specific form of ATBS that can be obtained by the controlled crystallization of the ATBS monomer. Document US10,759,746 describes this hydrated form of ATBS.

[0052] In a preferred embodiment according to the present invention, monomer A is preferably a cationic monomer.

[0053] Monomer B The water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) may contain one or more non-ionic monomers (referred to as "monomer B").

[0054] Advantageously, the non-ionic monomer B may be selected in particular from the group comprising water-soluble vinyl-type monomers. Preferred monomers belonging to this class are, for example, acrylamide, acrylonitrile, methacrylamide, and mixtures thereof. Preferably, this is acrylamide.

[0055] The water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) advantageously contains between 40 and 99 mol%, preferably between 30 and 98 mol%, more preferably between 60 and 97 mol%, even more preferably between 70 and 96 mol% of non-ionic monomer B.

[0056] Monomer C The water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) may contain one or more zwitterionic monomers or hydrophobic monomers (referred to as "monomer C").

[0057] A zwitterionic monomer is an ionic monomer with an overall charge of zero. In practice, a zwitterionic monomer has the same number of cationic and anionic charges.

[0058] Advantageously, the zwitterionic monomers that can be used in the context of the present invention can be selected, in particular, from vinyl-type motifs, in particular derivatives of acrylamide, acrylic, allyl, or maleic. Preferably, this monomer contains an amine or quaternary ammonium functional group and a carboxylic (or carboxylate), sulfonic (or sulfonate), or phosphoric (or phosphate) acid-type functional group. Zwitterionic monomers can be mentioned in particular, but not limited to, derivatives of dimethylaminoethyl acrylate, such as 2-((2-(acryloyloxy)ethyl)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; derivatives of dimethylaminoethyl methacrylate, 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, [2-(methacryloyloxy)ethyl](dimethylammonio)acetate; derivatives of dimethylamino propyl acrylamide, such as 2-((3-acrylamidopropyl)dimethylammonio)ethane-1-sulfonate, 3-((3-acrylamidopropyl)dimethylammonio)propane-1-sulfonate, 4-((3-acrylamidopropyl)dimethylammonio)butane-1-sulfonate, [3-(acryloyl)oxy)propyl](dimethylammonio)acetate, dimethylaminopropyl methylacrylamide; or further, 2-((3-methacrylamidopropyl)dimethylammonio)ethane-1-sulfonate, 3-((3-me dimethylammonio)propane-1-sulfonate, 4-((3-methacrylamidopropyl)dimethylammonio)butane-1-sulfonate, and derivatives such as propyl [3-(methacryloyloxy)](dimethylammonio)acetate, and mixtures thereof may also be selected.

[0059] Other zwitterionic monomers are described by the applicant in document WO2021123599.

[0060] The water-soluble dialdehyde-functionalized polymer according to the invention advantageously comprises from 0.001 to 30 mol%, preferably from 0.01 to 20 mol%, more preferably from 0.1 to 15 mol% of zwitterionic monomer.

[0061] Advantageously, the hydrophobic monomer C is an ester of (meth)acrylic acid having an alkyl chain of C4-C 30 alkyl, propoxylated, ethoxylated, or ethoxylated and propoxylated arylalkyl (C4-C 30 alkyl, C4-C 30 aryl); a derivative of (meth)acrylamide presenting an alkyl chain of C1-C3, propoxylated, ethoxylated, ethoxylated and propoxylated arylalkyl (C4-C 30 alkyl, C4-C 30 aryl), or dialkyl (C4-C 30 alkyl); a derivative of alkylarylsulfonate (C4-C 30 alkyl, C4-C 30 alkyl, C4-C 30 aryl), or mono- or di-substituted amide of (meth)acrylamide presenting an alkyl chain of C4-C 30 alkyl, C4-C 30 aryl), or a derivative of (meth)acrylamide presenting an alkyl chain of C4-C 30 alkyl, propoxylated, ethoxylated, ethoxylated and propoxylated arylalkyl (C4-C 30 alkyl, C4-C 30 aryl), or C4-C 30 dialkyl; alkylarylsulfonate (C4-C 30alkyl, C4-C 30 may be selected from the group consisting of aryl), and mixtures thereof.

[0062] Water-soluble dialdehyde-functionalized polymers (preferably glyoxalated) generally contain less than 1 mol% of hydrophobic monomer C. It can be free of hydrophobic monomer C.

[0063] When the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) according to the invention contains one or more hydrophobic monomers C, they are present in an amount such that the polymer remains water-soluble.

[0064] The amounts of the respective different monomers will be adjusted by those skilled in the art so as not to exceed 100 mol% during the production of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated). Preferably, monomers A and B represent the monomers of 100 mol% of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated).

[0065] Structuring system The structuring system of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) is (i) at least one compound I and (ii) at least one compound II and contains.

[0066] Compound I is selected from allylsulfonic acid, methallylsulfonic acid, allyldisulfonic acid, methallyldisulfonic acid, their salts, and mixtures thereof. Preferably, this is methallylsulfonic acid, for example, sodium methallylsulfonate.

[0067] The chlorinated form preferably corresponds to an alkali metal salt (Li, Na, K...), an alkaline earth metal salt (Ca, Mg...), or an ammonium salt (for example, ammonium ion or tertiary ammonium). A preferred salt is the sodium salt.

[0068] The water-soluble dialdehyde-functionalized polymer preferably contains Compound I in an amount between 500 and 50,000 ppm, preferably between 1,000 and 20,000 ppm, more preferably between 2,000 and 10,000 ppm, based on the total mass of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer.

[0069] Compound II used in the context of the present invention has the formula (1)

[0070]

Chemical formula

[0071] [R1 and R2 are each independently a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, or a CH2-OH group, and R1 and R2 are not both hydrogen atoms (when R2 = H, R1 ≠ H; when R1 = H, R2 ≠ H)] is of this kind.

[0072] Compound II is preferably selected from N,N-dimethylacrylamide, N,N-diethylacrylamide, N,N-isopropylacrylamide, N-methylolacrylamide, and mixtures thereof. Preferably, it is N,N-dimethylacrylamide.

[0073] The water-soluble dialdehyde-functionalized polymer according to the present invention preferably contains Compound II in an amount between 500 and 50,000 ppm, preferably between 1,000 and 20,000 ppm, more preferably between 2,000 and 10,000 ppm, based on the total mass of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer.

[0074] In the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated), the mass ratio of Compound I to Compound II is preferably between 0.01 and 100, more preferably between 0.1 and 10.

[0075] In a preferred embodiment according to the present invention, the amount of Compound I is greater than the amount of Compound II. Accordingly, the mass ratio of Compound I to Compound II is advantageously greater than 1 and 100 or less, preferably greater than 1 and 10 or less.

[0076] Optional The water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) may further contain at least one crosslinking agent. This crosslinking agent can be selected, for example, from vinyl functional groups, especially polyethylene unsaturated monomers such as allyl and acrylic (having at least two unsaturated functional groups), or from monomers having at least two epoxy functional groups. For example, methylene bisacrylamide (MBA), triallylamine, tetraallylammonium chloride, 1,2-dihydroxyethylene bis-(N-acrylamide), and mixtures thereof can be mentioned. Preferably, it is methylene bisacrylamide (MBA).

[0077] The amount of the crosslinking agent in the water-soluble dialdehyde-functionalized polymer is advantageously included between 5 and 5,000 ppm, more preferably between 50 and 3,000 ppm, based on the total mass of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer.

[0078] In a specific embodiment according to the present invention, the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) does not contain a crosslinking agent.

[0079] The water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) according to the present invention may also contain at least one migrating agent selected, for example, from methanol, isopropyl alcohol, sodium hypophosphite, 2-mercaptoethanol, and mixtures thereof. Other migrating agents include xanthates, dithiocarbonates, dithiocarbamates, and trithiocarbonate types, and mixtures thereof, and preferably, it is sodium hypophosphite.

[0080] The amount of the migrating agent in the water-soluble dialdehyde-functionalized polymer is preferably included between 10 and 10,000 ppm, more preferably between 50 and 5,000 ppm, based on the total mass of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer.

[0081] In certain embodiments according to the invention, the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) does not contain a migrating agent.

[0082] Physical characteristics of the base polymer The base polymer preferably has a mass average molecular weight included between 1,000,000 and 25,000,000 Daltons, preferably between 2,000,000 and 15,000,000 Daltons, more preferably between 2,000,000 and 10,000,000 Daltons, for example between 3,000,000 and 10,000,000 Daltons. This is the mass average molecular weight.

[0083] The mass average molecular weight is preferably measured by gel permeation chromatography coupled to a Malls detector.

[0084] The base polymer is preferably obtained and used in liquid form.

[0085] The viscosity of the solution containing the base polymer is preferably included between 1,000 and 50,000 cps, preferably between 2,000 and 20,000 cps, for example between 5,000 and 20,000 cps.

[0086] Renewable origin In a preferred embodiment according to the invention, the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) is manufactured using at least partially renewable and non-fossil origin monomers.

[0087] In the context of the present invention, the term "renewable and non-fossil origin" designates the origin of compounds resulting from biomass or synthesis gas (syngas), i.e., the result of one or more chemical conversions carried out on one or more raw materials of natural and non-fossil origin. The terms "bio-derived" or "bio-based" can also be used to characterize the renewable and non-fossil origin of a compound. The renewable and non-fossil origin of a compound results from a circular economy and includes, for example, renewable and non-fossil raw materials that have been recycled one or more times previously during a recycling process of materials resulting from biomass, such as materials resulting from polymer depolymerization or from the conversion of pyrolysis oil.

[0088] According to the present invention, "at least partially renewable and non-fossil origin" means a bio-derived carbon content comprised between 5% and 100% by weight, preferably at least 30%, more preferably at least 50%, even more preferably at least 70%, more preferably at least 90%, even more preferably at least 100% with respect to the total carbon mass of said compound.

[0089] In the context of the present invention, the standard ASTM D6866-21, method B is used to characterize the bio-derived nature of a compound and to determine the bio-derived content of said compound. The value is expressed as the mass percentage of bio-derived carbon with respect to the total mass of carbon in said compound.

[0090] Gradient The base polymer and the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) according to the present invention are gradient polymers.

[0091] A polymer having a gradient structure is a polymer composed of at least two monomers with a gradual change in monomer composition, different from a block polymer that undergoes a sudden change in composition and also different from a random polymer that does not have a continuous change in composition. In a gradient polymer, due to the gradual change in composition along the length of the polymer chain, interchain and intrachain repulsive forces are not readily observed.

[0092] The gradient can be formed by spontaneous or forced gradients. Spontaneous gradient polymerization is due to differences in monomer reactivity. Forced gradient polymerization involves varying the monomer composition introduced over the entire polymerization time.

[0093] The forced method involves (1) introduction of a first fraction of monomer into the reactor, (2) addition of at least one additional monomer fraction, preferably different from the first, and (3) polymerization of the monomers introduced into the reactor. The polymerization of the monomers is initiated by the introduction of the first fraction.

[0094] The addition of the additional monomer fraction may be carried out in parallel with the introduction of the first fraction of monomer into the reactor (so that the introduction of the fractions can start and end simultaneously). Alternatively, the start of the first monomer supply (first fraction) to the reactor may precede the start of the addition of the second monomer fraction. Alternatively, the first and second fractions can be introduced simultaneously, but the time taken to add the second fraction may be longer than the time taken to add the first fraction to the reactor. This embodiment is also applicable to methods using at least three monomer fractions.

[0095] According to the method of the present invention, the resulting water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) is formed by sequential addition of monomers, i.e., it is preferably a forced gradient.

[0096] The method according to the present invention comprises a first fraction (F1) and at least two additional fractions (F2 and F3). At least one of the fractions F1, F2, and F3 of the method is different from the other fractions. Preferably, the fractions F1, F2, and F3 are different. By different fractions, it means fractions composed of different monomers (ratio and / or properties of monomers) and / or compounds I and II (ratio and / or properties of compounds I and II), respectively.

[0097] Polymerization method A sequential polymerization method of a water-soluble dialdehyde-functionalized polymer (advantageously, glyoxalated) comprises the following steps: a) A step of forming a solution (S1) comprising at least a first fraction (F1) containing at least one monomer selected from monomers A and B and at least one compound selected from compounds I and II; b) A step of polymerization 1 (PO1) of fraction F1 to form a solution of a first gradient polymer (PG1); c) A step of adding a second fraction (F2) containing at least one monomer selected from monomers A and B and at least one compound selected from compounds I and II to the solution containing PG1; d) A step of polymerization 2 (PO2) of fraction F2 to PG1 to form a solution of a second gradient polymer (PG2); e) A step of adding a third fraction (F3) containing at least one monomer selected from monomers A and B and at least one compound selected from compounds I and II to the solution containing PG2; f) A step of polymerization 3 (PO3) of fraction F3 to PG2 to form a solution containing a base polymer; g) A step of diluting the solution containing the base polymer and reacting at least one dialdehyde (advantageously, glyoxal) with the base polymer to obtain a water-soluble dialdehyde-functionalized polymer (advantageously, glyoxalated); and At least one of fractions F1, F2, or F3 contains at least one monomer A, At least one of fractions F1, F2, or F3 contains at least one monomer B, At least one of fractions F1, F2, or F3 contains at least one compound I, At least one of fractions F1, F2, or F3 contains at least one compound II.

[0098] This method may include the addition of additional fractions, but not after step g) of the dialdehyde reaction.

[0099] The improved performance of the polymers obtained by the method of the present invention can possibly be attributed to the fact that the polymerization is carried out sequentially and continuously, i.e., without interruption.

[0100] "Sequentially" means that the polymerization of the monomers of the base polymer takes place in a plurality of fractions and without interruption, i.e., the fractions are added continuously and the polymerization does not stop. It means that the different steps a) - f) are carried out sequentially. In other words, in order to obtain the base polymer at the end of the polymerization, the first fraction of monomers can be poured in (in a fluid form), polymerized to form the first gradient polymer PG1, which continues to polymerize with fraction F2 to form gradient polymer PG2, which itself continues to polymerize with fraction F3. At least one of fractions F1, F2, and F3 is different from the other fractions. Preferably, fractions F1, F2, and F3 are different. By adding different fractions during the polymerization process, it is possible to obtain a gradient in the base polymer composition.

[0101] In certain embodiments, the polymerization can stop after PO1 and / or PO2 and continue at different localizations. In this embodiment, fraction F X added to the gradient polymer PG X+1 formed during the previous steps (X = 1 or 2) polymerizes with and interacts with PG X to form, interact to form PGX+1 is formed and the process continues in subsequent steps to finally obtain the base polymer. When the polymerization is complete, step g) is carried out on the base polymer, following the end of the polymerization or at another time (later). Preferably, it is carried out subsequently. In other words, the base polymer used for step g) no longer continues to polymerize. However, it undergoes a post-treatment that modifies its chemical structure. Since step g) requires dilution of the solution containing the base polymer, it is preferably carried out in a reactor different from the polymerization reactor. The dilution of the base polymer is preferably carried out in water.

[0102] In the polymerization process according to the invention, the sum of the molar percentages of the different fractions of monomers is equal to the sum of the molar percentages of the monomers of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated).

[0103] Step a), formation of a solution (S1) containing a first fraction (F1) Solution (S1) Solution S1 typically - a solvent, - an initiator, - and a first fraction F1 and is composed of.

[0104] The solvent is preferably water or a solvent in which the monomers and the base polymer are soluble. Preferably, the solvent is water.

[0105] The polymerization initiator used may be a compound that dissociates into radicals under the polymerization conditions, for example, organic peroxides, hydroperoxides, hydrogen peroxide, persulfates, azo compounds, and redox pairs. The use of water-soluble initiators is preferred. In some cases, it is advantageous to use a mixture of various polymerization initiators, for example, a mixture of a redox catalyst and an azo compound. Preferably, they are persulfates.

[0106] In a particular embodiment, solution S1 is formed in a polymerization tank by mixing the solvent, the initiator, and fraction F1.

[0107] In this particular embodiment, fraction F1 may be added to the solvent / initiator mixture all at once, in portions, or poured in (in a flowing form), i.e., gradually and continuously (e.g., dropwise). Preferably, fraction F1 is added to the polymerization tank all at once.

[0108] In a particular embodiment of the present invention, the initiator and fraction F1 are poured into the polymerization tank containing the solvent (in a flowing form). They may be added separately or pre-mixed. Preferably, they are added separately.

[0109] In a preferred embodiment of the present invention, the initiator is added continuously throughout the polymerization process. In this case, the initiator is advantageously added in parallel with different fractions during different polymerization steps, as well as during possible aging steps of different gradient polymers (PG1 and PG2) and the base polymer.

[0110] In this preferred embodiment of the present invention, the duration of the initiator pouring is between 50 minutes and 560 minutes, preferably between 130 minutes and 430 minutes.

[0111] The first fraction (F1) Advantageously, fraction F1 contains monomers (A and B and optionally C) between 10 and 45% by weight, preferably between 15 and 40% by weight, based on the total weight of the monomers of the water-soluble dialdehyde-functionalized polymer.

[0112] Fraction F1 advantageously contains monomer A (advantageously cationic) between 0 and 65 mol%, preferably between 5 and 55 mol%, based on the total number of moles of monomers in fraction F1.

[0113] Fraction F1 advantageously contains non-ionic monomer B between 35 and 100 mol%, preferably between 45 and 95 mol%, based on the total number of moles of monomers in fraction F1.

[0114] Fraction F1 preferably contains from 250 to 30,000 ppm, preferably from 500 to 10,000 ppm, more preferably from 1,000 to 7,000 ppm of Compound I, based on the total mass of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated).

[0115] Fraction F1 preferably contains from 250 to 30,000 ppm, preferably from 500 to 10,000 ppm, more preferably from 1,000 to 5,000 ppm of Compound II, based on the total mass of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated).

[0116] The different monomers and compounds contained in fraction F1 are preferably added in the form of a solution. These solutions can be added to the polymer tank, separately or as a mixture, all at once, in portions, or poured in (in a flowing form), i.e., dropwise, to form solution S1. Preferably, the addition is made as a mixture and all at once.

[0117] When fraction F1 is poured in (in a flowing form), the pouring preferably continues for between 10 and 80 minutes, preferably between 40 and 70 minutes.

[0118] In a preferred embodiment, fraction F1 is prepared in the reactor (polymerization tank) before the addition of the initiator.

[0119] In a preferred embodiment, fraction F1 contains at least one monomer A, at least one monomer B, at least one Compound I, and at least one Compound II.

[0120] Step b), Polymerization of fraction F1 to form the first gradient polymer (PG1) Polymerization 1 (PO1) Prior to the polymerization PO1, the atmosphere in the polymerization tank can be replaced with an inert gas such as nitrogen or argon, for example.

[0121] The polymerization PO1 is generally a radical polymerization. A polymerization initiator, in particular, an initiator that dissociates into radicals under the polymerization conditions, can be used.

[0122] The polymerization PO1 generally starts at a temperature included between 70 and 90 °C, preferably between 75 and 85 °C, and then the polymerization temperature is controlled using cooling means so as not to exceed 95 °C.

[0123] The polymerization PO1 typically continues for between 10 and 80 minutes, preferably between 40 and 70 minutes.

[0124] Advantageously, when the first monomer, the solvent, and the initiator are in contact, the polymerization advantageously starts, in other words, the duration of the polymerization PO1 advantageously corresponds to the duration of the injection of fraction F1.

[0125] Gradient polymer (PG1) At the end of the polymerization PO1, a gradient polymer (PG1) is obtained.

[0126] In a particular embodiment according to the invention, the gradient polymer PG1 is aged for between 5 and 60 minutes, preferably between 10 and 30 minutes.

[0127] "Is aged" means that after the polymerization is finished, the temperature of the medium is maintained between 80 and 90 °C in order to allow an increase in viscosity through branching phenomena inside the polymer. This definition of aging applies to all steps of the polymerization process.

[0128] Step c) Addition of the second fraction (F2) to the solution containing PG1 Second fraction F2 Advantageously, fraction F2 contains between 30 and 80% by weight, preferably between 40 and 70% by weight, of monomers (A and B and optionally C) with respect to the total weight of the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated).

[0129] Fraction F2 advantageously contains between 0 and 50 mol%, preferably between 0 and 40 mol%, of monomer A (advantageously cationic) with respect to the total number of moles of monomers in fraction F2.

[0130] Fraction F2 advantageously contains between 0 and 100 mol%, preferably between 60 and 100 mol%, of non-ionic monomer B with respect to the total number of moles of monomers in fraction F2.

[0131] Fraction F2 contains between 250 and 30,000 ppm, preferably between 500 and 10,000 ppm, more preferably between 1,000 and 5,000 ppm, of compound I with respect to the total weight of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated).

[0132] Fraction F2 contains between 250 and 30,000 ppm, preferably between 500 and 10,000 ppm, more preferably between 1,000 and 5,000 ppm, of compound II with respect to the total weight of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated).

[0133] The different monomers and compounds contained in fraction F2 are advantageously added in solution form. These solutions can be added to the polymer tank separately or as a mixture, all at once, in several portions, or poured in (in flowing form). Preferably, the addition is made as a mixture and poured in (in flowing form).

[0134] When fraction F2 is poured in (in a flowing form), the pouring preferably continues for between 10 and 100 minutes, more preferably between 30 and 90 minutes.

[0135] By adding fraction F2 in a flowing form (for example, by dropping), it becomes possible to control the heat generation of a reaction that may otherwise become excessively high even when using a cooler.

[0136] In a preferred embodiment, fraction F2 contains at least one monomer A, at least one monomer B, at least one compound I, and at least one compound II.

[0137] Step d), polymerization of fraction F2 to PG1 to form a second gradient polymer (PG2) Polymerization (PO2) Polymerization PO2 is carried out as a continuation of polymerization PO1, which is carried out under the same time and temperature conditions (preferably 70 - 90 °C).

[0138] Polymerization PO2 preferably continues for between 10 and 100 minutes, more preferably between 30 and 90 minutes.

[0139] Polymerization PO2 starts from the addition of the first monomer of fraction F2.

[0140] Preferably, the duration of polymerization PO2 corresponds to the duration of pouring of fraction F2.

[0141] Gradient polymer (PG2) At the end of polymerization PO2, a gradient polymer (PG2) is obtained.

[0142] In a specific embodiment of the present invention, gradient polymer PG2 is aged for between 5 and 6 minutes, more preferably between 10 and 30 minutes.

[0143] Step e) Addition of a third fraction (F3) to the solution containing PG2 Fraction F3 Advantageously, fraction F3 contains monomers (A and B and optionally C) between 5 and 40% by weight, preferably between 10 and 30% by weight, relative to the total weight of the monomers (A and B and optionally C) of the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated).

[0144] Fraction F3 advantageously contains monomer A (advantageously cationic) between 0 and 50 mol%, preferably between 0 and 35 mol%, relative to the total number of moles of monomers in fraction F3.

[0145] Fraction F3 advantageously contains nonionic monomer B between 50 and 100 mol%, preferably between 65 and 100 mol%, relative to the total number of moles of monomers in fraction F3.

[0146] Fraction F3 advantageously contains compound I between 0 and 10,000 ppm, preferably between 10 and 5000 ppm, more preferably between 20 and 1,000 ppm, relative to the total weight of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated).

[0147] Fraction F3 advantageously contains compound II between 0 and 10,000 ppm, preferably between 0 and 1,000 ppm, relative to the total weight of monomers A and B (and optionally monomer C) of the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated).

[0148] The different monomers and compounds contained in fraction F3 are advantageously added in solution form. These solutions can be added to the polymer tank separately or as a mixture, all at once, in several portions, or poured in (in a flowing form), i.e., dropwise. Preferably, the addition is made as a mixture and poured in (in a flowing form).

[0149] When fraction F3 is poured in (in a flowing form), the pouring advantageously continues for between 10 and 100 minutes, preferably between 30 and 90 minutes.

[0150] By adding fraction F3 in a flow form (e.g., dropping), it becomes possible to control the heat generation of a reaction that may otherwise become excessively high even when a cooler is used.

[0151] In a preferred embodiment, fraction F3 contains at least one monomer B and at least one compound I.

[0152] In one embodiment, the amount of compound I in fraction F3 is less than 500 ppm, preferably less than 300 ppm, preferably less than 200 ppm, and even more preferably less than 100 ppm.

[0153] Such a small amount enables the desired physical and specific properties of the base polymer and, subsequently, the final water-soluble dialdehyde-functionalized polymer.

[0154] Step f), polymerization of fraction F3 to PG2 to form a water-soluble dialdehyde-functionalized polymer Polymerization (PO3) Polymerization PO3 is carried out as a continuation of polymerization PO2, which is carried out under the same time and temperature conditions as PO2 (advantageously, for 10 to 100 minutes, preferably 30 to 90 minutes, at 70 to 90 °C).

[0155] Polymerization PO3 starts from the addition of the first monomer of fraction F3.

[0156] Advantageously, the duration of polymerization PO3 corresponds to the duration of pouring in fraction F3.

[0157] At the end of polymerization PO3, a base polymer is obtained.

[0158] In a specific embodiment according to the present invention, before removing the residual monomers, the base polymer is aged for 5 to 60 minutes, preferably 10 to 30 minutes.

[0159] The reaction is stopped by the addition of excess initiator and / or water, and this step is used to remove residual monomers that may be present in the solution containing the base polymer.

[0160] Optional step The method according to the invention can also include additional steps and is not limited to the steps described above.

[0161] In certain embodiments of the invention, the polymerization method according to the invention can include the addition of additional fractions that make up the base polymer.

[0162] In a preferred embodiment of the invention, the base polymer is aged for between 10 and 100 minutes, preferably between 30 and 90 minutes, after step f) of polymerizing PO3 and prior to step g). When additional fractions are added, the aging is carried out after the last polymerization step and before step g).

[0163] In certain embodiments of the invention, the crosslinking agent and / or the mobility agent are added during at least one of the steps described above.

[0164] In certain embodiments of the invention, the crosslinking agent is added to fraction F1 and / or fraction F2.

[0165] When a crosslinking agent is added, it is preferably selected from the crosslinking agents listed above.

[0166] When a crosslinking agent is added, its amount is preferably between 5 and 5,000 ppm, preferably between 50 and 3,000 ppm, based on the total mass of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) (monomers A, B, and optionally C).

[0167] In certain embodiments of the invention, the mobility agent is added to fraction F1 and / or fraction F2.

[0168] When a migrating agent is added, it is preferably selected from the migrating agents listed above.

[0169] When a migrating agent is added, its amount is preferably included between 10 and 10,000 ppm, preferably between 50 and 5,000 ppm, relative to the total mass of the water-soluble dialdehyde-functionalized polymer (preferably glyoxalated) (monomers A, B, and optionally C).

[0170] Step g), dialdehyde functionalization of the base polymer (preferably glyoxalation) Preferably, the dialdehyde functionalization reaction (preferably glyoxalation) comprises at least the following sequential steps: g1) a step of diluting a solution containing the base polymer (preferably in water) to form a diluted base polymer solution (SD1); g2) an optional step of adjusting the pH of SD1 to at least 10; g3) a step of adding at least one dialdehyde to the solution obtained in step g1) or g2) to form a diluted solution (SD2); g4) an optional step of acidifying the solution obtained in step g3) to a pH included between 2 and 4, preferably between 2.5 and 3.5, to form a diluted solution (SD3) and includes.

[0171] Preferably, in step g1), the amount of the base polymer in the diluted solution (SD1) is included between 1 and 15% by mass, preferably between 2 and 13% by mass. The dilution is preferably carried out in water.

[0172] Preferably, the dialdehyde added in step g3) is selected from the group consisting of glyoxal, glutaraldehyde, furan-dialdehyde, adipaldehyde, succinaldehyde, dialdehyde starch, 2,2-dimethoxyacetaldehyde, diepoxy compounds, and mixtures thereof. Preferably, this is glyoxal.

[0173] Advantageously, the mass concentration in the dialdehyde is between 5 and 30%, preferably between 10 and 25%, more preferably between 15 and 20%, based on the total mass of monomers A and B (optionally C).

[0174] Advantageously, step g3) is carried out at a temperature comprised between 19 and 26 °C with stirring in the reactor. Preferably, and after g2), the pH at the start of the addition of the dialdehyde is maintained between 10 and 11, for example with a soda solution in 10% by mass of water. After the reaction of the dialdehyde with the base polymer in step g3), the viscosity of the aqueous solution increases.

[0175] In certain embodiments according to the invention, if g2) is not carried out, at the end of step g3), the pH is adjusted to at least 8, for example with a soda solution in 10% by mass of water, and the pH is maintained throughout all of step g3).

[0176] In certain embodiments of the invention, the diluted solution (SD2) is used directly and introduced into the paper pulp.

[0177] Step g3) advantageously lasts between 2 and 90 minutes, preferably between 5 and 75 minutes.

[0178] Once the desired viscosity has been reached, step g4) may be carried out.

[0179] Step g4) is preferably carried out in the reactor at a temperature comprised between 19 and 26 °C with stirring, for example by the addition of an acid, such as concentrated sulfuric acid.

[0180] Advantageously, the reaction of dialdehyde formation (advantageously glyoxalation) is monitored by measurements of viscosity, turbidity, delta P... etc.

[0181] At the end of step g4) or g3), a water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) is obtained.

[0182] In certain embodiments of the present invention, step g) includes step g5) which involves adding at least one dialdehyde to the solution obtained in step g4).

[0183] Advantageously, the dialdehyde is selected from the group described above, and preferably it is the same as in step g3).

[0184] In certain embodiments and advantageously, the mass concentration of the dialdehyde added in steps g3) and g5) is between 5 and 30%, preferably between 10 and 25%, more preferably between 15 and 20%, relative to the total mass of monomers A and B (optionally C).

[0185] Advantageously, the mass concentration added in step g3) is the same as the mass concentration added in step g5).

[0186] In certain embodiments of the present invention, the microcrystalline cellulose compound is reacted with a water-soluble dialdehyde-functionalized polymer (advantageously, it is glyoxalated).

[0187] Then, in all of the specific embodiments described above, instead of the water-soluble dialdehyde-functionalized polymer (alone) according to the present invention, a microcrystalline cellulose / water-soluble dialdehyde-functionalized polymer mixture can be added to the paper pulp as an additive.

[0188] Advantageously, the microcrystalline cellulose compound is selected from nanofibrillated cellulose, microfibrillated cellulose, nanocrystalline cellulose, and nanocellulose.

[0189] Advantageously, between 10% and 100% by mass, preferably between 10 and 50% by mass, of the microcrystalline cellulose compound is added to the water-soluble dialdehyde-functionalized polymer (advantageously, it is glyoxalated), relative to the mass of the water-soluble dialdehyde-functionalized polymer.

[0190] The water-soluble dialdehyde-functionalized polymer of the present invention is produced in solution but can be used in solid form. In practice, the solid form is obtained, inter alia, by a method consisting of drying the solution of step g). The technical principles of solid / liquid separation are drying by atomization or spraying (consisting of creating a cloud of fine droplets in a hot gas stream over a controlled time period), drum drying, those of a fluidized bed dryer.

[0191] Paper-making method The present invention also relates to a method for producing paper or cardboard, comprising the steps of: (1) adding a water-soluble dialdehyde-functionalized polymer according to the present invention (advantageously glyoxalated) to an aqueous suspension of fibers; and (2) forming a sheet of paper or cardboard. Accordingly, the present invention relates to the use of a water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) in the paper-making method.

[0192] The various steps in the paper-making production method, cardboard, etc. are known and are in accordance with techniques that are part of the knowledge of those skilled in the art, and since they are known and remain classical knowledge of those skilled in the art, it is not necessary to describe them in more detail. If necessary, reference can be made to the Handbook for Pulp & Paper Technologists, 4 th Edition, G.A. Smook.

[0193] According to the present invention, the water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) is added in the paper-making method before or after the formation of a sheet of paper or cardboard, etc. Accordingly, contacting the cellulose material with the polymer of the present invention is carried out in various ways, particularly according to typical methods known to those skilled in the art.

[0194] Water-soluble dialdehyde-functionalized polymers (advantageously, glyoxalated) can be added to cellulose materials in the form of diluted or undiluted aqueous solutions. It can be applied by impregnation techniques or added directly to the fibrous suspension at any point where dry strength agents are normally introduced in the method for producing paper.

[0195] Therefore, the polymers according to the invention can be introduced into thick or thin paper stocks. It can be added in a mixing pump before the headbox or the filter screen. Preferably, the polymer is introduced before the headbox.

[0196] Preferably, the polymers according to the invention are industrially introduced into the fibrous suspension, i.e., before its dilution with pulp water (thick paper stock). The consistency of the pulp is about 1 to 5% by mass of cellulose fibers.

[0197] The papermaking method according to the invention can be carried out using any type of paper pulp, such as virgin fiber pulp (kraft, sulfite), recycled fiber, deinked pulp, mechanical and thermomechanical pulp, etc.

[0198] Water-soluble dialdehyde-functionalized polymers (advantageously, glyoxalated) are advantageously added directly to the fibrous suspension before sheet formation.

[0199] It can be added at a single point of introduction or at two points of introduction.

[0200] The papermaking method according to the invention may also include the addition of other additives and / or polymers as required, and examples include, but are not limited to, biocides, coagulants, yield improvers, flocculants, and starch.

[0201] Use The present invention also relates to the use of this water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) in the recovery of hydrocarbons (oil and / or gas); in the drilling or cementing of wells; in the stimulation of hydrocarbon wells (oil and / or gas), for example, in hydraulic fracturing, conditioning, conversion; in the water treatment of open, closed, or semi-closed cycles; in the treatment of fermentation mashes; in the treatment of sludge; in construction; in the treatment of timber; in the treatment of hydraulic compositions (concrete, cement, mortar, and aggregates); in mining; in the formulation of cosmetics; in the formulation of detergents; in textile manufacturing; in the geothermal sector; in the manufacture of sanitary napkins; or in agriculture.

[0202] The present invention also relates to the use of a water-soluble dialdehyde-functionalized polymer (advantageously glyoxalated) as a flocculant, coagulant, binder, fixing agent, viscosity reducer, thickener, absorbent, anti-friction agent, drainage agent, charge-holding agent, dehydrating agent, conditioning agent, stabilizer, fixing agent, film-forming agent, sizing agent, high-performance water reducer, clay inhibitor, or dispersant.

[0203] The present invention and the advantages derived therefrom will become more apparent in the following examples given by way of illustration and not limitation of the present invention.

Examples

[0204] List of abbreviations DADMAC: Diallyldimethylammonium chloride (monomer A) AMD: Acrylamide (monomer B) DMAM: Dimethylacrylamide (compound II) SMS: Sodium methallylsulfonate (compound I) SPS: Sodium persulfate (polymerization initiator) MBA: Methylenebisacrylamide (crosslinking agent) PEI: Polyethyleneimine

[0205] Description of the molecular weight characterization of GPC-Malls Gel permeation chromatography is a method that enables the separation of polymers according to their hydrodynamic volume, which is connected to a Malls detector and enables the measurement of light scattering at multiple angles.

[0206] The synthesized polymers are analyzed under the following conditions. - Instrument: GPC-2 - Column: Shodex SB-807-HQ & SB-805 custom - Method Temperature: 30 °C Mobile phase: 0.5 M NaNO3, HEPES (pH = 8), 100 ppm NaN3 Injection: 100 μL Flow rate: 0.3 mL / min Detection: (i) Light scattering detector (MALS): Absolute molar mass (ii) Refractive index measurement (RI): Concentration

[0207] Viscosity is measured using a Brookfield viscometer at 25 °C with a speed of 60 rpm using a Brookfield LVI module.

[0208] Production of Polymers 1-3 (INV) according to the present invention Base Polymer 1 (P1) First order: Gradient Polymer PG1 In a 1 liter reactor equipped with a mechanical stirrer, thermometer, condenser, and nitrogen gas immersion rod, a first fraction F1 containing 140 g of water, 89.3 g of acrylamide (50% by mass in water), 16.7 g of diallyldimethylammonium chloride (64% by mass in water), 1 g of citric acid, 0.5 g of dimethylacrylamide, and 0.87 g of sodium methallylsulfonate is introduced into the reactor. The medium is heated and maintained at a temperature between 79 and 81 °C using a water bath. The addition of 0.05 g of sodium persulfate enables the initiation of this starter and starts the polymerization (PO1) of the monomers to form the first gradient polymer PG1.

[0209] Second order: gradient polymer PG2 Once the exothermic reaction has ended, start the pouring: Add an initiator (44 g of SPS at 0.33% by mass in water) over 130 minutes, and simultaneously add a second fraction F2 consisting of 24.3 g of water, 178.6 g of acrylamide (50% by mass in water), 16.7 g of DADMAC (64% by mass in water), 0.5 g of dimethylacrylamide, and 0.41 g of sodium methallyl sulfonate over 50 minutes. Once fraction F2 has been poured in, age the gradient polymer PG2 for 10 minutes (the polymerization PO2 to form the gradient polymer PG2 occurs during the pouring of fraction F2 and during the aging).

[0210] Third order: base polymer 1 (P1) Next, pour in a third fraction F3 consisting of 115.6 g of water, 89.3 g of acrylamide (50% by mass in water), and 0.01 g of sodium methallyl sulfonate over 60 minutes. At the end of the addition of fraction F3, age the polymer for 10 minutes (the polymerization PO3 to form the polymer occurs during the pouring of fraction F3 and during the aging).

[0211] Once aging is complete, add 140 g of water and 0.15 g of sodium persulfate. When the desired viscosity is reached, stop the reaction by adding 0.6 g of sodium bisulfite (40% by mass in water) and 140 g of water. Apply a new aging for 60 minutes before cooling. The solution containing the base polymer 1 (P1) has a pH of 3.5, 20% by mass of active substance, a viscosity of 4,100 cps, and a molecular weight of 4,300,000 Da obtained by GPC-Malls.

[0212] Glyoxalation of the base polymer 1 (P1) according to the invention (P1-A / B(INV)) Polymer 1-A (P1-A) 64 g of base polymer 1 (P1) and 728 g of water are introduced into a 1-liter reactor equipped with a mechanical stirrer. The reactor is equipped with a pH probe. After stirring for 10 minutes, the pH is adjusted to 10.3 with a soda solution in 10% by mass in water. The temperature is maintained between 20 and 22 °C. 8 g of glyoxal (40% by mass in water) is added. By checking the pH and monitoring the viscosity, it becomes possible to obtain a product of 39 cps after a reaction time of 58 minutes. When the desired viscosity is reached, the reaction is stopped by lowering the pH to less than 3.5 by adding H2SO4 (92% by mass in water), and polymer 1-A (P1-A) according to the present invention is obtained.

[0213] Polymer 1-B (P1-B) The protocol for the production of polymer 1-A is reproduced by changing the amount of glyoxal added, and polymer 1-B (P1-B) according to the present invention is obtained. The composition is summarized in Table 2 (Table 3).

[0214] Base polymers 2 and 3 (P2 and P3) To prepare base polymers 2 (P2) and 3 (P3) according to the present invention, the protocol for the production of polymer 1 is reproduced by changing the composition of different fractions. The composition of the different fractions used to obtain these base polymers is summarized in Table 1a (Table 1).

[0215] Glyoxalation of base polymers 2 and 3 (INV) according to the present invention (P2-A / B and P3-A / B) To obtain polymers 2-A, 2-B, 3-A, and 3-B, the protocol for the production of polymer 1-A / B is reproduced by changing the amount of glyoxal added. Their composition is summarized in Table 2 (Table 3).

[0216] Production of comparative example polymers 4 to 7 (CE1 to CE4) Polymer 4 (CE1) This polymer is produced in one order.

[0217] Into a 1-liter reactor equipped with a mechanical stirrer, thermometer, condenser, and nitrogen gas immersion rod, 526 g of water and 33.1 g of DADMAC (64% by mass in water) are introduced. The pH is adjusted to 2.5 using H2SO4. The medium is heated and maintained at a temperature between 79 and 81 °C using a water bath. 357.8 g of acrylamide (50% by mass in water) is incorporated by continuous pouring over 90 minutes, and a solution of sodium persulfate is incorporated by pouring over 90 minutes. After 10 minutes of aging, 0.6 g of sodium bisulfite (40% by mass in water) is added to react any remaining monomers present. A new aging period of 60 minutes is applied before cooling. The resulting solution containing base polymer 4 (CE1) has a pH of 5.0, 20.1% by mass of active substance, a viscosity of 4,100 cps, and a molecular weight of 429,000 Da obtained by GPC-Malls.

[0218] Glyoxalation of Polymer 4 (CE1-A / B) The protocol for the production of Polymer 1-A is reproduced while varying the amount of glyoxal added. The glyoxalated polymers 4-A (CE1-A) and 4-B (CE1-B) of the comparative examples are obtained, and their compositions are summarized in Table 2 (Table 3).

[0219] Polymer 5 (CE2) According to Example 4 of Document FR2987375, Polymer 5 (CE2) is obtained.

[0220] Glyoxalation of Polymer 5 (CE2-A / B) The protocol for the production of Polymer 1-A is reproduced while varying the amount of glyoxal added. Polymers 5-A (CE2-A) and 5-B (CE2-B) are obtained, and their compositions are summarized in Table 2 (Table 3).

[0221] Polymer 6 (CE3) According to Example 12 of Document FR2987375, Polymer 6 is obtained.

[0222] Glyoxalation of Polymer 6 (CE3-A / B) The protocol for the production of Polymer 1-A is reproduced while varying the amount of glyoxal added. Polymers 6-A (CE3-A) and 6-B (CE3-B) are obtained, and their compositions are summarized in Table 2 (Table 3).

[0223] Polymer 7 (CE4-A / B) Polymer 7 (CE4) is produced according to a protocol that is the same only in two orders for Polymer 1. The compositions of different fractions of the polymerization process for producing Base Polymers 1 to 3 (P1 to P3) according to the present invention and Base Polymers of Comparative Examples (CE1 to CE4) are summarized in Table 1a (Table 1).

[0224] In this Table 1a (Table 1), the monomer content described in each fraction represents the molar mass percentage of the AMD (or DADMAC) monomer with respect to the total molar mass of the corresponding monomer in all fractions. Therefore, for example, the sum of the percentages of the AMD monomer in the three fractions is equal to 100%.

[0225] The contents of Compound I (SMS) and II (DMAM) are expressed in mass ppm with respect to the total mass of the monomers in the three fractions.

[0226] [Table 1]

[0227] The physicochemical properties of these obtained base polymers are described in Table 1b (Table 2) below.

[0228] [Table 2]

[0229] Table 2 (Table 3) describes the viscosities and compositions of glyoxalated Polymers 1 to 3 (P1-A to P3-B) according to the present invention and glyoxalated Polymers CE1-A to CE4-B of Comparative Examples.

[0230]

Table 3

[0231] Applicability test The wet pulp used in all of the applicability examples is obtained by the disintegration of dry pulp to obtain a final aqueous mass concentration of 1%. This is pH-neutral pulp using 100% recycled newsprint fibers.

[0232] Evaluation of drainage performance (DDA) under reduced pressure The DDA (Dynamic Drainage Analyzer) enables the automatic determination of the time (in seconds) required to vacuum-dewater a fibrous suspension on a cloth. The polymer is added to the wet pulp (0.6 liters of pulp to 1.0% mass) in the cylinder of the DDA under agitation at 1000 revolutions per minute. T = 0 s: Agitation of the pulp T = 10 s: Addition of the polymer T = 30 s: Stopping of the agitation and vacuum drainage at 200 mBar for 60 s.

[0233] The pressure under the cloth is recorded as a function of time. As water is discharged from the fibrous mat, air passes through it, which causes a break in the slope on the curve representing the pressure under the cloth as a function of time. The time, expressed in seconds, associated with this break in slope on the curve corresponds to the drainage time. The shorter the time, the better the vacuum drainage.

[0234] Performance in dry-strength applications, 80 g / m -2 basis weight 80 g / m -2 To finally obtain a sheet corresponding to a basis weight of 80 g / m, the necessary amount of pulp is taken as a sample.

[0235] Introduce the wet pulp into a dynamic hand sheet former tank and hold it under stirring. Add different compounds to this pulp according to the previously defined order. Generally, there is a contact time of 30 - 45 seconds between the additions of polymers.

[0236] Make paper hand sheets using an automatic dynamic hand sheet former. Place blotting paper and a forming fabric into the tank of the dynamic hand sheet former, and then start the rotation of the tank at 1000 revolutions per minute -1 to create a water wall. Distribute the treated pulp onto the water wall to form a fibrous mat on the forming fabric.

[0237] After draining the water, recover the fibrous mat, press it under a press with four bars fed out, and then dry it at 117 °C. Pack the obtained sheets overnight in a room with controlled humidity and temperature (50% relative humidity and 23 °C). Then, measure the dryness resistance properties of all the sheets obtained by this procedure.

[0238] Measure the burst strength using a Messmer Buchel M 405 burst tester according to the TAPPI T403 om - 02 standard specification.

[0239] The amount of polymer added is expressed in kg of active polymer per ton of dry fiber. Trials were conducted at 1.5 kg / t and are summarized in Table 3 (Table 4). The results are expressed as a percentage increase compared to nothing (no polymer).

[0240]

Table 4

[0241] It is interesting to note that the polymers of the present invention (P1-A to P3-B) exhibit improved drainage performance (DDA) and mechanical characteristics (rupture; DBL; breakage in the dry state) with respect to polymers manufactured according to conventional methods (CE1-A and CE1-B), or polymers of the prior art (CE2-A to CE4-B).

Claims

1. A water-soluble dialdehyde-functionalized polymer comprising: - at least one monomer A which is cationic or anionic; - at least one monomer B which is nonionic; - at least one structuring system which (i) comprises at least one compound I selected from allylsulfonic acid, methallylsulfonic acid, allyldisulfonic acid, methallyldisulfonic acid, salts thereof, and mixtures thereof; and (ii) at least one compound II of formula (1) 【Chemical 1】 [wherein, R 1 and R 2 are each independently a hydrogen atom, or a methyl group, an ethyl group, an isopropyl group, or a CH 2 -OH group, R 1 and R 2 are not both hydrogen atoms which is different from at least one monomer B and at least one structuring system containing the same; wherein the polymer lacks anionic monomers other than compound I; wherein the polymer is obtained according to the following steps: a) a step of forming a solution (S1) comprising at least a first fraction (F1) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II; b) a step of polymerization 1 (PO1) of fraction F1 to form a solution of a first gradient polymer (PG1); c) a step of adding a second fraction (F2) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II to the solution containing PG1; d) a step of polymerization 2 (PO2) of fraction F2 to PG1 to form a solution of a second gradient polymer (PG2); e) a step of adding a third fraction (F3) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II to the solution containing PG2; f) a step of polymerization 3 (PO3) of fraction F3 to PG2 to form a solution containing a base polymer; g) a step of diluting the solution containing the base polymer and reacting at least one dialdehyde with the base polymer to obtain a water-soluble dialdehyde-functionalized polymer; wherein at least one of fractions F1, F2 or F3 contains at least one monomer A; wherein at least one of fractions F1, F2 or F3 contains at least one monomer B; wherein at least one of fractions F1, F2 or F3 contains at least one compound I; wherein at least one of fractions F1, F2 or F3 contains at least one compound II; ​ ​ Monomer A is different from a mixture of a cationic monomer and an anionic monomer. When monomer A is anionic, the water-soluble dialdehyde-functionalized polymer does not contain a cationic monomer. When monomer A is cationic, the water-soluble dialdehyde-functionalized polymer does not contain an anionic monomer except for Compound I. Water-soluble dialdehyde-functionalized polymer. **Claim 2** The water-soluble dialdehyde-functionalized polymer according to claim 1, wherein at least one of fraction F1, F2, or F3 is different from the other fractions. **Claim 3** The water-soluble dialdehyde-functionalized polymer according to claim 1 or 2, wherein at least one monomer A is cationic. **Claim 4** At least one monomer A is selected from dimethylaminoethyl acrylate quaternized, dimethylaminoethyl methacrylate quaternized, diallyldimethylammonium chloride, propyltrimethylammonium acrylamide chloride, propyltrimethylmethacrylamide ammonium chloride, and mixtures thereof, and the dialdehyde is selected from the group consisting of glyoxal, glutaraldehyde, furan-dialdehyde, adipaldehyde, succinaldehyde, dialdehyde starch, 2,2-dimethoxyethanal, diepoxy compounds, and mixtures thereof. The water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 3. **Claim 5** The water-soluble dialdehyde-functionalized polymer according to claim 1 or 2, wherein at least one nonionic monomer B is selected from acrylamide, acrylonitrile, and methacrylamide, and the dialdehyde is glyoxal. **Claim 6** The water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 5, comprising Compound I in an amount between 500 and 50,000 ppm based on the total mass of monomers A and B. **Claim 7** The water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 6, comprising Compound II in an amount between 500 and 50,000 ppm based on the total mass of monomers A and B. **Claim 8** The water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 7, wherein compound II is selected from N,N-dimethylacrylamide, N,N-diethylacrylamide, N,N-isopropylacrylamide, N-methylolacrylamide, and mixtures thereof.

9. The water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 8, wherein the mass ratio of compound I to compound II is included between 0.01 and 100.

10. A method for sequentially producing a water-soluble dialdehyde-functionalized polymer, comprising the following steps: a) A step of forming a solution (S1) containing at least a first fraction (F1) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II, wherein at least one monomer A is a cationic monomer or an anionic monomer, at least one monomer B is a nonionic monomer, at least one compound I is selected from allylsulfonic acid, methallylsulfonic acid, allyldisulfonic acid, methallyldisulfonic acid, their salts, and mixtures thereof, at least one compound II is of formula (1) which is different from at least monomer B 【Chemical 2】 [R 1 and R 2 are each independently a hydrogen atom, or a methyl group, an ethyl group, an isopropyl group, or a CH 2 -OH group, R 1 and R 2 are not both hydrogen atoms in the step, b) A step of polymerization 1 (PO1) of fraction F1 to form a solution of a first gradient polymer (PG1), c) A step of adding a second fraction (F2) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II to the solution containing PG1, d) A step of polymerization 2 (PO2) of fraction F2 to PG1 to form a solution of a second gradient polymer (PG2), e) A step of adding a third fraction (F3) containing (1) at least one monomer selected from monomers A and B and (2) at least one compound selected from compounds I and II to the solution containing PG2, f) A step of polymerization 3 (PO3) of fraction F3 to PG2 to form a solution containing a base polymer, g) A step of diluting the solution containing the base polymer and reacting at least one dialdehyde with the base polymer to obtain a water-soluble dialdehyde polymer and including At least one of fractions F1, F2, or F3 contains at least one monomer A, At least one of fractions F1, F2, or F3 contains at least one monomer B, At least one of fractions F1, F2, or F3 contains at least one compound I, At least one of fractions F1, F2, or F3 contains at least one compound II, Monomer A is different from a mixture of a cationic monomer and an anionic monomer, When monomer A is anionic, the water-soluble dialdehyde-functionalized polymer does not contain a cationic monomer, When monomer A is cationic, the water-soluble dialdehyde-functionalized polymer does not contain an anionic monomer except for compound I, Method.

11. The method according to claim 10, characterized in that at least one of fractions F1, F2, or F3 is different from the others.

12. The method according to claim 10 or 11, characterized in that the initiator is added continuously throughout the polymerization process and the dialdehyde is glyoxal.

13. The method according to any one of claims 10 to 12, characterized by including an aging step for 10 to 100 minutes after the step f) of polymerization (PO3).

14. The dialdehyde reaction comprises at least the following steps: g1) A step of diluting a solution containing a base polymer to form a diluted solution (SD1) of the base polymer; g2) An optional step of adjusting the pH of SD1 to at least 10; g3) A step of adding at least one dialdehyde to the solution obtained in step g1) or g2) to form a diluted solution (SD2); g4) An optional step of acidifying the solution obtained in step g3) to a pH included between 2 and 4 to form a diluted solution (SD3) The method according to any one of claims 10 to 12, characterized by including these steps.

15. A method for manufacturing paper or cardboard, comprising a step of adding the water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 9 to an aqueous solution of fibers, and a step of forming a sheet of paper or cardboard.

16. Use of the water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 9 in the recovery of hydrocarbons; in well drilling or cementing; in stimulation of hydrocarbon wells; in water treatment in an open circulation; in the treatment of fermentation mashes; in sludge treatment; in construction; in wood processing; in the treatment of hydraulic compositions; in mining; in the formulation of cosmetics; in the formulation of detergents; in textile manufacturing; in the geothermal sector; in the manufacture of sanitary napkins; or in agriculture.

17. Use of the water-soluble dialdehyde-functionalized polymer according to any one of claims 1 to 9 as a flocculant, coagulant, binder, fixing agent, viscosity reducer, thickener, absorbent, anti-friction agent, drainage agent, charge-holding agent, dehydrating agent, conditioning agent, stabilizer, fixing agent, film-forming agent, sizing agent, high-performance water reducer, clay inhibitor, or dispersant.

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