Patent Application
20240263400
The present disclosure generally relates to the field of papermaking. More particularly, the disclosure relates to compositions and particles that may be used in a papermaking process.
A papermaking process may include the steps of pulping wood or some other source of papermaking fibers and producing a paper material from the pulp, the paper mat being an aqueous slurry of cellulosic fiber. Next, the slurry may be deposited on a moving papermaking wire or fabric and a sheet may be formed from the solid components of the slurry by draining the water. The sheet is then pressed and dried to further remove water and, in some instances, the process may include rewetting the dry sheet by passing it through a size press and further drying it to form a paper product.
When conducting a papermaking process, a number of factors need to be considered to assure the quality of the resulting paper product. For example, when draining water from the slurry, care should be taken to retain as many fibers as possible. Additionally, the process should be carried out in a manner such that the resulting sheet has adequate strength.
The ability to form paper of superior strength at minimal cost is important to the manufacture of paper products. Paper strength is dependent upon a number of factors, including choice of fibers, refining methods, press loading, and chemical additives employed. There has been an increase in the use of lower quality fiber sources and the use of such fibers often leads to the need for increased refining, greater press loads, and/or chemical additives.
Greater refining usually results in undesirable paper properties, such as increased paper density, reduced tear, decreased porosity, and slower production times. Increasing press loads has mechanical limitations, such as sheet crushing, and can also lead to inefficient paper production. Thus, chemical additives are commonly added to the papermaking process to enhance the properties of paper. These additives can be used to increase the strength, such as internal strength, surface strength, compressive strength, bursting strength, dry strength, and tensile breaking strength, of the paper product.
The present disclosure provides compositions, particles, components, and methods for improving papermaking processes.
In some embodiments, the present disclosure provides an aqueous colloidal composition, comprising a colloidal particle comprising a cationic polymer embedded within a colloidal hydroxide complex, wherein the colloidal particle comprises an anionic component.
In some embodiments, an overall charge of the colloidal particle is positive.
In some embodiments, the anionic component comprises a polymer. The polymer may comprise, for example, a monomer selected from the group consisting of acrylamide, acrylic acid, naphthalene sulfonic acid, formaldehyde, glyoxalated polyacrylamide, and any combination thereof. In certain embodiments, the polymer comprises acrylamide and acrylic acid. In some embodiments, the polymer comprises from about 1 mol % to about 30 mol % of the acrylic acid. In some embodiments, the polymer has a weight average molecular weight from about 10 kDa to about 5,000 kDa.
In certain embodiments, the anionic component comprises colloidal silica, carboxymethyl cellulose, a micropolymer, or any combination thereof.
In some embodiments, the aqueous colloidal composition comprises a pH of about 6 to about 8.5.
In some embodiments, the colloidal hydroxide complex is a colloidal ferric hydroxide complex or a colloidal aluminum hydroxide complex.
In certain embodiments, the cationic polymer comprises an anionic monomer, a non-ionic monomer, a zwitterionic monomer, and any combination thereof. In some embodiments, the cationic polymer comprises a monomer selected from the group consisting of acrylamide, methacrylamide, 2-(dimethylamino)ethyl acrylate (“DMAEA”), 2-(dimethylamino)ethyl methacrylate (“DMAEM”), 3-(dimethylamino)propyl methacrylamide (“DMAPMA”), 3-(dimethylamino)propyl acrylamide (“DMAPA”), 3-methacrylamidopropyl-trimethyl-ammonium chloride (“MAPTAC”), 3-acrylamidopropyl-trimethyl-ammonium chloride (“APTAC”), N-vinyl pyrrolidone (“NVP”), diallyldimethylammonium chloride (“DADMAC”), diallylamine, 2-(acryloyloxy)-N,N,N-trimethylethanaminium chloride (“DMAEA.MCQ”), 2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride (“DMAEM.MCQ”), N,N-dimethylaminoethyl acrylate benzyl chloride (“DMAEA.BCQ”), N,N-dimethylaminoethyl methacrylate benzyl chloride (“DMAEM.BCQ”), 2-acrylamido-2-methylpropane sulfonic acid (“AMPS”), 2-acrylamido-2-methylbutane sulfonic acid (“AMBS”), acrylamide tertbutylsulfonate (“ATBS”), [2-methyl-2-[(1-oxo-2-propenyl)amino]propyl]-phosphonic acid, acrylic acid, methacrylic acid, maleic acid, itaconic acid, a salt of any of the foregoing monomer units, and any combination thereof.
In some embodiments, the cationic polymer comprises a glyoxalated polyacrylamide (GPAM), a polyvinylamine (PVAM), a polyethylenimine (PEI), a polyamidoamine epichlorohydrin (PAE), or any combination thereof.
In certain embodiments, the colloidal particle is water-insoluble.
In some embodiments, the cationic polymer comprises from about 1 mol % to about 50 mol % of a cationic monomer.
In some embodiments, a weight ratio of the aluminum hydroxide and/or the ferric hydroxide to the cationic polymer in the colloidal particle is from about 0.1:99 to about 99:0.1.
In certain embodiments, the colloidal particle has an average particle size ranging from about 0.01 to about 1,000 microns.
In some embodiments, the cationic polymer comprises a carboxylic acid. In some embodiments, the cationic polymer comprises from about 1 mol % to about 8 mol % of the carboxylic acid.
In certain embodiments, the polymer of the anionic component and/or the cationic polymer is linear.
In some embodiments, at least a portion of the cationic polymer is ionically bonded to at least a portion of the anionic component.
The present disclosure also provides a pulp fiber comprising a first layer adsorbed onto a surface of the pulp fiber, and a second layer disposed on the first layer, wherein the first layer comprises a colloidal particle comprising a cationic polymer embedded within a colloidal hydroxide complex, and wherein the second layer comprises an anionic component. In certain embodiments, the first layer consists of or consists essentially of the colloidal particle. In certain embodiments, the second layer consists of or consists essentially of the anionic component.
In some embodiments, an overall charge of the colloidal particle is positive.
In some embodiments, the anionic component comprises a polymer, the polymer comprising a monomer selected from the group consisting of acrylamide, acrylic acid, naphthalene sulfonic acid, formaldehyde, glyoxalated polyacrylamide, and any combination thereof. In certain embodiments, the polymer comprises acrylamide and acrylic acid. In some embodiments, the polymer comprises from about 1 mol % to about 30 mol % of the acrylic acid. In some embodiments, the polymer has a weight average molecular weight from about 10 kDa to about 5,000 kDa.
In some embodiments, the colloidal hydroxide complex is a colloidal ferric hydroxide complex or a colloidal aluminum hydroxide complex.
In certain embodiments, the cationic polymer comprises an anionic monomer, a non-ionic monomer, a zwitterionic monomer, and any combination thereof. In some embodiments, the cationic polymer comprises a monomer selected from the group consisting of acrylamide, methacrylamide, DMAEA, DMAEM, DMAPMA, DMAPA, MAPTAC, APTAC, NVP, DADMAC, diallylamine, DMAEA.MCQ, DMAEM.MCQ, DMAEA.BCQ, DMAEM.BCQ, AMPS, AMBS, ATBS, [2-methyl-2-[(1-oxo-2-propenyl)amino]propyl]-phosphonic acid, acrylic acid, methacrylic acid, maleic acid, itaconic acid, a salt of any of the foregoing monomer units, and any combination thereof.
In some embodiments, the cationic polymer comprises a GPAM, a PVAM, a PEI, a PAE, or any combination thereof.
In some embodiments, the colloidal particle is water-insoluble.
In certain embodiments, the cationic polymer comprises from about 1 mol % to about 50 mol % of a cationic monomer.
In some embodiments, a weight ratio of the aluminum hydroxide and/or the ferric hydroxide to the cationic polymer in the colloidal particle is from about 0.1:99 to about 99:0.1.
In some embodiments, the colloidal particle has an average particle size ranging from about 0.01 to about 1,000 microns.
In certain embodiments, the cationic polymer comprises a carboxylic acid. In some embodiments, the cationic polymer comprises from about 1 mol % to about 8 mol % of the carboxylic acid.
In some embodiments, the polymer of the anionic component and/or the cationic polymer is linear.
In certain embodiments, at least a portion of the cationic polymer is ionically bonded to at least a portion of the anionic component.
In some embodiments, a pulp furnish or a paper sheet comprises the fiber.
The present disclosure also provides a method of improving a papermaking process. The method comprises adding a colloidal particle to a papermaking machine, the colloidal particle comprising a cationic polymer embedded within a colloidal hydroxide complex, and adding an anionic component to the papermaking machine.
In some embodiments, the colloidal hydroxide complex is a colloidal aluminum hydroxide complex or a colloidal ferric hydroxide complex.
In some embodiments, at least some of the colloidal particle is added to the papermaking machine before the anionic component.
In certain embodiments, from about 0.1 to about 100 lb/ton of the colloidal hydroxide complex, relative to solid fiber, is added to the papermaking machine. In some embodiments, from about 0.1 to about 100 lb/ton of the anionic component, relative to solid fiber, is added to the papermaking machine.
In some embodiments, the colloidal particle and the anionic component are added to a thin stock, a thick stock, a headbox, before the headbox, after the headbox, before a press section, or any combination thereof.
Also disclosed in the present application is a method of improving a papermaking process. The method comprises adding a composition to a papermaking machine, wherein the composition comprises a cationic polymer and an aluminum salt and/or a ferric salt, wherein the composition comprises a weight ratio of the aluminum salt and/or the ferric salt to the cationic polymer from about 0.05:1 to 100:1, and adding an anionic component to the papermaking machine.
In certain embodiments, at least some of the composition is added to the papermaking machine before the anionic component.
In some embodiments, from about 0.1 to about 100 lb/ton of the cationic polymer, relative to solid fiber, is added to the papermaking machine. In some embodiments, from about 0.1 to about 100 lb/ton of the aluminum salt and/or ferric salt, relative to solid fiber, is added to the papermaking machine. In certain embodiments, from about 0.1 to about 100 lb/ton of the anionic component, relative to solid fiber, is added to the papermaking machine.
In some embodiments, the composition and the anionic component are added to a thin stock, a thick stock, a headbox, before the headbox, after the headbox, before a press section, or any combination thereof.
In some embodiments, the composition comprises from about 0.01 wt. % to about 10 wt. % of the cationic polymer.
In certain embodiments, the cationic polymer comprises a Huggins constant of about 0.0 to about 1. In certain embodiments, the cationic polymer comprises a conformation plot slope of about 0.05 to about 1.
In some embodiments, the aluminum salt is selected from the group consisting of aluminum chloride, aluminum chloride hydrate, aluminum sulfate, alum, PAC, aluminum chlorohydrate, a compound having the formula AlnCl(3n-m)(OH)m, wherein m is an integer from 0-100, n is an integer from 1-100, and m is less than 3n, and any combination thereof.
In some embodiments, the ferric salt is selected from the group consisting of ferric chloride, ferric sulfate, a polyferric salt, and any combination thereof.
In certain embodiments, the papermaking machine comprises a papermaking process water and the composition and the anionic component are added to the papermaking process water.
In some embodiments, the papermaking process water comprises a member selected from the group consisting of a fiber, a paper sheet, a fines particle, a filler particle, a pulp, and any combination thereof.
In some embodiments, the method may further comprise forming a colloidal particle in the papermaking process water. In certain embodiments, the colloidal particle comprises the cationic polymer embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex. In some embodiments, the colloidal particle is formed in the absence of a fiber and/or in the presence of a fiber.
In certain embodiments, the composition and the anionic component exclude a polysaccharide, an anionic polysaccharide, and/or a fiber. In certain embodiments, the cationic polymer and the anionic component exclude a hydroxamic acid group, an isocyanate group, N-bromoamine and/or N-chloroamine.
The foregoing has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter that form the subject of the claims of this application. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent embodiments do not depart from the spirit and scope of the disclosure as set forth in the appended claims.
A detailed description of the invention is hereafter described with specific reference being made to the drawings in which:
Various embodiments of the presently disclosed technology are described below. The relationship and functioning of the various elements of the embodiments may be better understood by reference to the following detailed description. However, embodiments are not limited to those explicitly described below.
Unless otherwise indicated, an alkyl group as described herein alone or as part of another group is an optionally substituted linear or branched saturated monovalent hydrocarbon substituent containing from, for example, one to about sixty carbon atoms, such as one to about thirty carbon atoms, in the main chain. Examples of unsubstituted alkyl groups include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, i-pentyl, s-pentyl, t-pentyl, and the like.
The terms “aryl” or “ar” as used herein alone or as part of another group (e.g., arylene) denote optionally substituted homocyclic aromatic groups, such as monocyclic or bicyclic groups containing from about 6 to about 12 carbons in the ring portion, such as phenyl, biphenyl, naphthyl, substituted phenyl, substituted biphenyl or substituted naphthyl. The term “aryl” also includes heteroaryl functional groups. It is understood that the term “aryl” applies to cyclic substituents that are planar and comprise 4n+2 electrons, according to Huckel's Rule.
“Cycloalkyl” refers to a cyclic alkyl substituent containing from, for example, about 3 to about 8 carbon atoms, preferably from about 4 to about 7 carbon atoms, and more preferably from about 4 to about 6 carbon atoms. Examples of such substituents include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and the like. The cyclic alkyl groups may be unsubstituted or further substituted with alkyl groups, such as methyl groups, ethyl groups, and the like.
“Heteroaryl” refers to a monocyclic or bicyclic 5- or 6-membered ring system, wherein the heteroaryl group is unsaturated and satisfies Huckel's rule. Non-limiting examples of heteroaryl groups include furanyl, thiophenyl, pyrrolyl, pyrazolyl, imidazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, isoxazolyl, oxazolyl, isothiazolyl, thiazolyl, 1,3,4-oxadiazol-2-yl, 1,2,4-oxadiazol-2-yl, 5-methyl-1,3,4-oxadiazole, 3-methyl-1,2,4-oxadiazole, pyridinyl, pyrimidinyl, pyrazinyl, triazinyl, benzofuranyl, benzothiophenyl, indolyl, quinolinyl, isoquinolinyl, benzimidazolyl, benzoxazolinyl, benzothiazolinyl, quinazolinyl, and the like.
Compounds of the present disclosure may be substituted with suitable substituents. The term “suitable substituent,” as used herein, is intended to mean a chemically acceptable functional group, preferably a moiety that does not negate the activity of the compounds. Such suitable substituents include, but are not limited to, halo groups, perfluoroalkyl groups, perfluoro-alkoxy groups, alkyl groups, alkenyl groups, alkynyl groups, hydroxy groups, oxo groups, mercapto groups, alkylthio groups, alkoxy groups, aryl or heteroaryl groups, aryloxy or heteroaryloxy groups, aralkyl or heteroaralkyl groups, aralkoxy or heteroaralkoxy groups, HO—(C═O)— groups, heterocylic groups, cycloalkyl groups, amino groups, alkyl- and dialkylamino groups, carbamoyl groups, alkylcarbonyl groups, alkoxycarbonyl groups, alkylaminocarbonyl groups, dialkylamino carbonyl groups, arylcarbonyl groups, aryloxy-carbonyl groups, alkylsulfonyl groups, and arylsulfonyl groups. In some embodiments, suitable substituents may include halogen, an unsubstituted C1-C12 alkyl group, an unsubstituted C4-C6 aryl group, or an unsubstituted C1-C10 alkoxy group. Those skilled in the art will appreciate that many substituents can be substituted by additional substituents.
The term “substituted” as in “substituted alkyl,” means that in the group in question (i.e., the alkyl group), at least one hydrogen atom bound to a carbon atom is replaced with one or more substituent groups, such as hydroxy (—OH), alkylthio, phosphino, amido (—CON(RA)(RB), wherein RA and RB are independently hydrogen, alkyl, or aryl), amino(-N(RA)(RB), wherein RA and RB are independently hydrogen, alkyl, or aryl), halo (fluoro, chloro, bromo, or iodo), silyl, nitro (—NO2), an ether (—ORA wherein RA is alkyl or aryl), an ester (—OC(O)RA wherein RA is alkyl or aryl), keto (—C(O)RA wherein RA is alkyl or aryl), heterocyclo, and the like.
When the term “substituted” introduces a list of possible substituted groups, it is intended that the term apply to every member of that group. That is, the phrase “optionally substituted alkyl or aryl” is to be interpreted as “optionally substituted alkyl or optionally substituted aryl.”
The term “aluminum salt” as used herein refers to an inorganic compound containing an aluminum ion, which includes, but is not limited to, alum, aluminum chloride, aluminum sulfate, PAC, and aluminum chlorohydrate. An aluminum salt is the compound that contributes aluminum ions in water solutions. It may include, but is not limited to, aluminum sulfate, aluminum chloride, aluminum phosphate, aluminum nitrate, and aluminum acetate.
The term “ferric salt” as used herein refers to an inorganic compound containing a ferric ion, which includes, but is not limited to, ferric chloride, ferric sulfate, polyferric sulfate, and polyferric chloride. A ferric salt is the compound that contributes ferric ions in water solutions. It may include, but is not limited to, ferric sulfate, ferric chloride, ferric phosphate, ferric nitrate, and ferric acetate.
The terms “co-feed,” “co-feeding,” “co-fed,” and the like refer to the addition of two or more components, ingredients, chemicals, and the like, to a location, such as a reaction vessel, storage container, and/or the papermaking machine, separately but essentially/substantially at the same time and location. For example, components selected from a cationic polymer, an inorganic salt, an anionic component, and any combination thereof, may be fed into a location in the wet end of a papermaking machine, such as the furnish, through separate injection pipes. Each pipe may continuously or intermittently inject chemical at the same time to a single location in the papermaking machine or to two or more locations in the papermaking machine that are in close proximity to each other (e.g., within about 1 to about 12 inches, such as from about 1 to about 10 inches, from about 1 to about 8 inches, or from about 1 to about 6 inches).
The term “degree of crosslinking” refers to how many connection bonds, on average, connect one polymer chain to another polymer chain. For example, a polymer sample with an average chain length of 1000 monomer units, wherein 10 monomer units are connected to another chain has a degree of crosslinking of 1%.
The terms “paper” or “paper product” as used herein encompass all types of fiber webs, such as paper, paperboard, board, tissue, towel, and/or sheet materials that contain paper fibers, such as natural and/or synthetic fibers including cellulosic fibers, wood fibers, cotton fibers, fibers derived from recycled paper, rayon, nylon, fiberglass, and polyolefin fibers, for example.
The term “weight average molecular weight” refers to the molecular weight average of polymer determined by static light scattering measurement, specifically by Size-Exclusion-Chromatography/Multi-Angle-Laser-Light-Scattering (SEC/MALLS) technique. The polymer of the present disclosure has a weight average molecular weight of from about 10,000 to about 10,000,000 Daltons.
The term “average particle size” refers to the average size of particles determined by a dynamic light scattering particle size analyzer when particles are less than 10 microns and by a laser diffraction size analyzer when the particle size is between 1 and 1,000 microns. The particle of the present disclosure has an average particle size of from about 0.01 to about 1,000 microns.
The present disclosure provides compositions, particles and methods of using the compositions and particles in papermaking processes. In some embodiments, the compositions and particles are used in methods for increasing the strength, such as the dry strength, of a paper product. The compositions, which may be aqueous compositions, include a colloidal particle, which may be interchangeably referred to as a “particle” throughout the present disclosure. The particle comprises a cationic polymer embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex. In some embodiments, the colloidal hydroxide complex comprises an anionic component. In certain embodiments, an overall charge of the particle is positive before addition of the anionic component. In certain embodiments, an overall charge of the particle is positive after addition of the anionic component. In some embodiments, an overall charge of the particle is negative after addition of the anionic component.
It has been surprisingly found that the particle significantly improved paper product strength compared to the polymer alone. Even more surprisingly, the inventors discovered that the addition of an anionic component further improved paper product strength. In some embodiments, the particle of the present disclosure is formed by mixing a trivalent ion, such as an aluminum salt and/or a ferric salt, with a polymer and the resulting mixture is added to a papermaking machine. In a typical papermaking process, however, if a trivalent ion, such as a polyaluminum chloride, is to be added to the process water, it is added alone as a charged scavenger. One of ordinary skill in the art would not attempt to combine it with other compounds, such as the cationic polymer of the present disclosure and/or the anionic component, before addition to the papermaking machine because it would be expected that the cationic polymer and/or anionic component would interfere with the charged scavenger and destroy its intended function.
The cationic polymer of the present disclosure is chemically and/or physically entangled and/or embedded in the colloidal aluminum hydroxide and/or colloidal ferric hydroxide complex.
The anionic component of the present disclosure associates with and/or bonds to the colloidal hydroxide complex and/or at least a portion of the cationic polymer. In some embodiments, at least a portion of the cationic polymer is ionically bonded to at least a portion of the anionic component. For example, an ionic bond may be formed between a cationically charged monomer of the cationic polymer and an anionically charged monomer of the anionic component.
In some embodiments, the anionic component comprises a polymer having a net/overall anionic charge. In certain embodiments, the polymer is a linear polymer. The polymer of the anionic component may comprise any monomer disclosed herein, such as a cationic, anionic, non-ionic, and/or zwitterionic monomer, so long as the polymer has a net/overall negative charge.
In certain embodiments, the polymer comprises a monomer selected from the group consisting of acrylamide, acrylic acid, naphthalene sulfonic acid, formaldehyde, glyoxalated polyacrylamide, and any combination thereof.
In some embodiments, the polymer comprises acrylamide and acrylic acid. For example, the polymer may comprise from about 1 mol % to about 30 mol % of the acrylic acid and about 70 mol % to about 99 mol % of the acrylamide. In certain embodiments, the polymer may comprise from about 1 mol % to about 20 mol %, from about 1 mol % to about 15 mol %, from about 1 mol % to about 10 mol %, from about 1 mol % to about 8 mol %, from about 1 mol % to about 5 mol %, from about 5 mol % to about 8 mol %, from about 5 mol % to about 10 mol %, from about 5 mol % to about 15 mol %, or from about 5 mol % to about 20 mol % of acrylic acid.
In some embodiments, the polymer of the anionic component comprises anionic GPAM.
In still further embodiments, the anionic component may comprise colloidal silica, carboxymethyl cellulose, a micropolymer, or any combination thereof.
The weight average molecular weight of the anionic component, such as the polymer of the anionic component, is not particularly limited. In some embodiments, the polymer has a weight average molecular weight from about 10 kDa to about 5,000 kDa, such as from about 10 kDa to about 4,000 kDa, from about 10 kDa to about 3,000 kDa, from about 10 kDa to about 2,000 kDa, from about 10 kDa to about 1,000 kDa, from about 10 kDa to about 750 kDa, from about 10 kDa to about 500 kDa, from about 10 kDa to about 400 kDa, from about 10 kDa to about 300 kDa, from about 10 kDa to about 200 kDa, from about 10 kDa to about 150 kDa, from about 10 kDa to about 100 kDa, from about 50 kDa to about 150 kDa, from about 50 kDa to about 200 kDa, from about 50 kDa to about 250 kDa, from about 50 kDa to about 300 kDa, from about 50 kDa to about 400 kDa, from about 50 kDa to about 500 kDa, from about 100 kDa to about 800 kDa, from about 100 kDa to about 600 kDa, from about 100 kDa to about 400 kDa, or from about 100 kDa to about 250 kDa.
The cationic polymer may include one or more anionic monomers, one or more cationic monomers, one or more non-ionic monomers, one or more zwitterionic monomers, or any combination of these monomers, so long as the cationic polymer has an overall/net positive charge.
In certain embodiments, the cationic polymer is water-soluble. In some embodiments, the cationic polymer comprises a carboxylic acid group.
For example, the cationic polymer may comprise from about 1 mol % to about 50 mol % of the carboxylic acid, such as about 1 mol % to about 40 mol %, about 1 mol % to about 30 mol %, about 1 mol % to about 20 mol %, about 1 mol % to about 10 mol %, about 10 mol % to about 50 mol %, about 20 mol % to about 50 mol %, about 30 mol % to about 50 mol % or about 40 mol % to about 50 mol % of the carboxylic acid.
In some embodiments, the cationic polymer comprises from about 1 mol % to about 8 mol %, from about 1 mol % to about 7 mol %, from about 1 mol % to about 6 mol %, from about 1 mol % to about 5 mol %, from about 1 mol % to about 4 mol %, from about 1 mol % to about 3 mol %, or from about 1 mol % to about 2 mol % of the carboxylic acid, such as about 1 mol %, about 2 mol %, about 3 mol %, about 4 mol %, about 5 mol %, about 6 mol %, about 7 mol %, or about 8 mol % of the carboxylic acid.
Illustrative, non-limiting examples of non-ionic monomers that may be included in the cationic polymer may be selected from acrylamide, methacrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, N-isopropylacrylamide, N-vinylformamide, N-vinylmethylacetamide, N-vinyl pyrrolidone, hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, N-tert-butylacrylamide, N-methylolacrylamide, diallylamine, allylamine, and the like.
Illustrative, non-limiting examples of anionic monomers include acrylic acid, and its salts, including, but not limited to sodium acrylate, and ammonium acrylate, methacrylic acid, and its salts, including, but not limited to sodium methacrylate, and ammonium methacrylate, AMPS, the sodium salt of AMPS, sodium vinyl sulfonate, styrene sulfonate, maleic acid, and its salts, including, but not limited to the sodium salt, and ammonium salt, sulfonate itaconate, sulfopropyl acrylate or methacrylate or other water-soluble forms of these or other polymerizable carboxylic or sulphonic acids, sulfomethylated acrylamide, allyl sulfonate, sodium vinyl sulfonate, itaconic acid, acrylamidomethylbutanoic acid, fumaric acid, vinylphosphonic acid, vinylsulfonic acid, allylphosphonic acid, sulfomethylated acrylamide, phosphonomethylated acrylamide, and the like.
Illustrative, non-limiting examples of cationic monomers include dialkylaminoalkyl acrylates and methacrylates and their quaternary or acid salts, including, but not limited to, dimethylaminoethyl acrylate methyl chloride quaternary salt, dimethylaminoethyl acrylate methyl sulfate quaternary salt, dimethylaminoethyl acrylate benzyl chloride quaternary salt, dimethylaminoethyl acrylate sulfuric acid salt, dimethylaminoethyl acrylate hydrochloric acid salt, dimethylaminoethyl methacrylate methyl chloride quaternary salt, dimethylaminoethyl methacrylate methyl sulfate quaternary salt, dimethylaminoethyl methacrylate benzyl chloride quaternary salt, dimethylaminoethyl methacrylate sulfuric acid salt, dimethylaminoethyl methacrylate hydrochloric acid salt, dialkylaminoalkylacrylamides or methacrylamides and their quaternary or acid salts, such as acrylamidopropyltrimethylammonium chloride, dimethylaminoethyl acrylate methyl chloride quaternary salt, dimethylaminoethyl acrylate benzyl chloride quaternary salt, dimethylaminoethyl methacrylate methyl chloride quaternary salt, dimethylaminoethyl methacrylate benzyl chloride quaternary salt, methacrylarnidopropyl trimethylammonium chloride, dimethylaminopropyl acrylamide methyl sulfate quaternary salt, dimethylaminopropyl acrylamide sulfuric acid salt, dimethylaminopropyl acrylamide hydrochloric acid salt, methacrylamidopropyltrimethylammonium chloride, dimethylaminopropyl methacrylamide methyl sulfate quaternary salt, dimethylaminopropyl methacrylamide sulfuric acid salt, dimethylaminopropyl methacrylamide hydrochloric acid salt, diethylaminoethylacrylate, diethylaminoethylmethacrylate, diallyldiethylammonium chloride, diallyldimethylammonium chloride, and the like.
Illustrative, non-limiting examples of zwitterionic monomers include N,N-dimethyl-N-acryloyloxyethyl-N-(3-sulfopropyl)-ammonium betaine, N,N-dimethyl-N-acrylamidopropyl-N-(2-carboxymethyl)-ammonium betaine, N,N-dimethyl-N-acrylamidopropyl-N-(3-sulfopropyl)-ammonium betaine, N,N-dimethyl-N-acrylamidopropyl-N-(2-carboxymethyl)-ammonium betaine, 2-(methylthio)ethyl methacryloyl-S-(sulfopropyl)-sulfonium betaine, 2-[(2-acryloylethyl)dimethylammonio]ethyl 2-methyl phosphate, 2-(acryloyloxyethyl)-2′-(trimethylammonium)ethyl phosphate, [(2-acryloylethyl)dimethylammonio]methyl phosphonic acid, 2-methacryloyloxyethyl phosphorylcholine (MPC), 2-[(3-acrylamidopropyl)dimethylammonio]ethyl 2′-isopropyl phosphate (AAPI), 1-vinyl-3-(3-sulfopropyl)imidazolium hydroxide, (2-acryloxyethyl) carboxymethyl methylsulfonium chloride, 1-(3-sulfopropyl)-2-vinylpyridinium betaine, N-(4-sulfobutyl)-N-methyl-N, N-diallylamine ammonium betaine (MDABS), N,N-diallyl-N-methyl-N-(2-sulfoethyl)ammonium betaine, and the like.
In some embodiments, the cationic polymer comprises a monomer selected from the group consisting of acrylamide, DMAEA, DMAEM, DMAPMA, DMAPA, MAPTAC, APTAC, NVP, DADMAC, DMAEA.MCQ, DMAEM.MCQ, DMAEA.BCQ, DMAEM.BCQ, AMPS, AMBS, ATBS, [2-methyl-2-[(1-oxo-2-propenyl)amino]propyl]-phosphonic acid, acrylic acid, methacrylic acid, maleic acid, itaconic acid, a salt of any of the foregoing monomer units, and any combination thereof.
In some embodiments, the cationic polymer comprises a GPAM, a PVAM, a PEI, a PAE, or any combination thereof.
Additional examples of cationic polymers can be found in Table 1.
In Table 1, DAAM refers to diacetone acrylamide, AAEM refers to acetoacetoxyethyl methacrylate, and MAA refers to methacrylic acid. In some embodiments, the cationic polymer comprises about 90 mol % acrylamide, about 8 mol % DMAEA.MCQ and about 2 mol % itaconic acid.
The mole percentage of each monomer in the cationic polymer is not particularly limited. In some embodiments, the polymer comprises from about 1 mol % to about 50 mol % of the cationic monomer. For example, the cationic polymer may comprise from about 1 mol % to about 45 mol %, from about 1 mol % to about 40 mol %, from about 1 mol % to about 35 mol %, from about 1 mol % to about 30 mol %, from about 1 mol % to about 25 mol %, from about 1 mol % to about 20 mol %, from about 1 mol % to about 15 mol %, from about 1 mol % to about 10 mol %, from about 1 mol % to about 5 mol %, from about 5 mol % to about 50 mol %, from about 5 mol % to about 45 mol %, from about 5 mol % to about 40 mol %, from about 5 mol % to about 35 mol %, from about 5 mol % to about 30 mol %, from about 5 mol % to about 25 mol %, from about 5 mol % to about 20 mol %, from about 5 mol % to about 15 mol %, or from about 5 mol % to about 10 mol % of a cationic monomer.
In some embodiments, the polymer comprises from about 0 mol % to about 50 mol % of the anionic monomer. For example, the cationic polymer may comprise from about 0 mol % to about 49 mol %, from about 0 mol % to about 45 mol %, from about 0 mol % to about 40 mol %, from about 0 mol % to about 35 mol %, from about 0 mol % to about 30 mol %, from about 0 mol % to about 25 mol %, from about 0 mol % to about 20 mol %, from about 0 mol % to about 15 mol %, from about 0 mol % to about 10 mol %, from about 0 mol % to about 5 mol %, from about 1 mol % to about 5 mol %, from about 1 mol % to about 10 mol %, from about 1 mol % to about 15 mol %, from about 1 mol % to about 20 mol %, from about 1 mol % to about 25 mol %, from about 1 mol % to about 30 mol %, from about 1 mol % to about 35 mol %, from about 1 mol % to about 40 mol %, or from about 1 mol % to about 49 mol % of an anionic monomer.
In some embodiments, the cationic polymer comprises from about 1 mol % to about 99 mol % of a non-ionic monomer. For example, the cationic polymer may comprise from about 1 mol % to about 90 mol %, from about 1 mol % to about 80 mol %, from about 1 mol % to about 70 mol %, from about 1 mol % to about 60 mol %, from about 1 mol % to about 50 mol %, from about 1 mol % to about 40 mol %, from about 1 mol % to about 30 mol %, from about 1 mol % to about 20 mol %, from about 1 mol % to about 10 mol %, from about 10 mol % to about 99 mol %, from about 20 mol % to about 99 mol %, from about 30 mol % to about 99 mol %, from about 40 mol % to about 99 mol %, from about 50 mol % to about 99 mol %, from about 60 mol % to about 99 mol %, from about 70 mol % to about 99 mol %, from about 80 mol % to about 99 mol %, or from about 90 mol % to about 99 mol % of a non-ionic monomer.
In some embodiments, the cationic polymer comprises from about 0 mol % to about 99 mol % of a zwitterionic monomer. For example, the cationic polymer may comprise from about 1 mol % to about 90 mol %, from about 1 mol % to about 80 mol %, from about 1 mol % to about 70 mol %, from about 1 mol % to about 60 mol %, from about 1 mol % to about 50 mol %, from about 1 mol % to about 40 mol %, from about 1 mol % to about 30 mol %, from about 1 mol % to about 20 mol %, from about 1 mol % to about 10 mol %, from about 10 mol % to about 99 mol %, from about 20 mol % to about 99 mol %, from about 30 mol % to about 99 mol %, from about 40 mol % to about 99 mol %, from about 50 mol % to about 99 mol %, from about 60 mol % to about 99 mol %, from about 70 mol % to about 99 mol %, from about 80 mol % to about 99 mol %, or from about 90 mol % to about 99 mol % of a zwitterionic monomer.
In certain embodiments, the cationic polymer disclosed herein comprises from about 5 mol % to about 15 mol % of the cationic monomer and about 0 mol % to about 5 mol % of the anionic monomer, and about 80 mol % to about 95 mol % of the non-ionic monomer, wherein the cationic polymer comprises a greater mol percentage of the cationic monomer as compared to the anionic monomer. For example, the cationic polymer may comprise from about 5 mol % to about 15 mol % of the cationic monomer, such as about 6 mol %, about 7 mol %, about 8 mol %, about 9 mol %, about 10 mol %, about 11 mol %, about 12 mol %, about 13 mol %, or about 14 mol % of the cationic monomer, about 1 mol %, about 2 mol %, about 3 mol %, about 4 mol %, or about 5 mol % of the anionic monomer, and about 82 mol %, about 84 mol %, about 86 mol %, about 88 mol %, about 90 mol %, about 92 mol %, or about 94 mol % of the non-ionic monomer.
In some embodiments, the cationic polymer and/or the anionic component is not a disaccharide or a polysaccharide. In certain embodiments, the cationic polymer and/or anionic component excludes monosaccharide monomers. In certain embodiments, the composition or particle disclosed herein excludes a polysaccharide, an anionic polysaccharide, and/or pulp fibers. In some embodiments, the cationic polymer and/or anionic component excludes a hydroxamic acid group, an isocyanate group, N-bromoamine and/or N-chloroamine. In certain embodiments, the cationic polymer and/or anionic component comprises unmodified/unreacted amide and/or amine side chains. In some embodiments, if the cationic polymer and/or anionic component comprises amide and/or amine side chains, less than 10% of those side chains, such as less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1% or 0%, are modified/reacted with other functional groups before the cationic polymer and/or anionic component is embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex.
In some embodiments, a cationic polymer of the present disclosure is a water-soluble amphoteric polymer containing a carboxylic acid group. In certain embodiments, a cationic polymer of the present disclosure may be linear, branched, crosslinked, structured, synthetic, semi-synthetic, natural, and/or functionally modified. A cationic polymer of the present disclosure can be in the form of a solution, a dry powder, a liquid, or a dispersion, for example.
The weight average molecular weight of the cationic polymer is not particularly limited. In some embodiments, the cationic polymer has a weight average molecular weight ranging from about 10,000 Da to about 10,000,000 Da. For example, the cationic polymer may have a molecular weight ranging from about 10,000 Da to about 5,000,000 Da, from about 10,000 Da to about 3,000,000 Da, from about 10,000 Da to about 1,000,000 Da, from about 10,000 Da to about 750,000 Da, from about 10,000 Da to about 500,000 Da, from about 10,000 Da to about 250,000 Da, from about 10,000 Da to about 100,000 Da, from about 10,000 Da to about 50,000 Da, from about 100,000 Da to about 10,000,000 Da, from about 500,000 Da to about 10,000,000 Da, from about 750,000 Da to about 10,000,000 Da, from about 1,000,000 Da to about 10,000,000 Da, from about 3,000,000 Da to about 10,000,000 Da, from about 5,000,000 Da to about 10,000,000 Da or from about 8,000,000 Da to about 10,000,000 Da.
As additional examples, the weight average molecular weight of the cationic polymer may be from about 200,000 Da to about 1,000,000 Da, such as from about 200,000 Da to about 800,000 Da, from about 200,000 Da to about 600,000 Da, or from about 300,000 to about 500,000 Da.
In some embodiments, the cationic polymer of the present disclosure comprises a Huggins constant of about 0.0 to about 1.0. For example, the Huggins constant of a cationic polymer disclosed herein may be from about 0.1 to about 0.9, about 0.1 to about 0.8, about 0.1 to about 0.7, about 0.1 to about 0.6, about 0.1 to about 0.5, about 0.1 to about 0.4, about 0.1 to about 0.3, about 0.1 to about 0.2, about 0.2 to about 0.8, about 0.2 to about 0.7, or about 0.2 to about 0.6.
The Huggins Equation is an empirical equation used to relate the reduced viscosity of a dilute polymer solution to the concentration of the polymer in solution. The Huggins equation states:
where ηs is the specific viscosity of a solution at a given concentration of a polymer in solution, [η] is the intrinsic viscosity of the solution, kH is the Huggins coefficient, and c is the concentration of the polymer in solution.
The Huggins equation is a useful tool because it can be used to determine the intrinsic viscosity [η] or IV, from experimental data by plotting ηs/c versus the concentration of the solution, c.
The Huggins constant may be calculated as follows:
where “RSV” stands for reduced specific viscosity and “IV” stands for intrinsic viscosity. The RSV is measured at a given polymer concentration and temperature and calculated as follows:
wherein η=viscosity of polymer solution; η0=viscosity of solvent at the same temperature; and c=concentration of polymer in solution. The units of concentration “c” are (grams/100 ml or g/deciliter). Therefore, the units of RSV are dL/g. In accordance with the present disclosure, for measuring RSV, the solvent used is 1.0 molar sodium nitrate solution. The polymer concentration is typically about 0.1 to about 1.0 g/dL. The RSV is measured at about 30° C. The viscosities η and η0 are measured using a Cannon Ubbelohde semimicro dilution viscometer, size 75.
In the SEC/MALLS analysis of the present disclosure, the cationic polymer solution was diluted with an aqueous mobile phase (0.3M NaCl, 0.1 M NaH2PO4, 25 ppm NaN3) to about 0.05%. About 200 μL of the solution was injected into a set of TSKgel PW columns (TSKgel GMPW+GMPW+G1000PW), and the mobile phase had a flow rate of about 1.0 mL/min. Bovine serum albumin (BSA) was used as standard for multiangle light scattering detector normalization. The calibration constant of the RI detector was verified with sodium chloride (NaCl).
The inventors discovered that a linear cationic polymer provides more dry strength than a crosslinked cationic polymer when complexed with a metal salt, such as PAC. Linearity of the cationic polymer can be defined using Huggins constant, with a lower Huggins constant indicating a more linear cationic polymer.
Certain cationic polymers disclosed herein may have a conformation plot slope of about 0.05 to about 1.0. For example, the cationic polymers may have a conformation plot slope of about 0.1 to about 1.0, about 0.2 to about 1.0, about 0.3 to about 1.0, about 0.4 to about 1.0, about 0.5 to about 1.0, about 0.05 to about 0.5, about 0.05 to about 0.3, or about 0.05 to about 0.1.
SEC/MALLS characterizes LCB (long chain branching) in macromolecules through conformation plots. A conformation plot is a log-log plot of the rms radius (radius of gyration, Rg) versus molar mass (M). Light scattering implemented as SEC/MALLS can effectively and rapidly characterize branching in polymers. Polymers with LCB exhibit lower slopes than the corresponding linear polymer, which differ depending on the extent of LCB. A conformation plot can be constructed by SEC/MALLS analysis (see AN1005: Identifying short-chain branched polymers with conformational analysis, Wyatt Technology, Chris Deng, Ph.D., the disclosure of which is incorporated into the present application in its entirety).
The conformation plot is acquired by taking the mean radius of gyration calculated based on the molecular weight at each point and the corresponding molecular weight on the chromatogram, and a corresponding slope is calculated from the conformation plot.
A linear polymer should have higher conformation slope, such as from about 0.5 to 1, about 0.6 to 1, about 0.7 to 1, or about 0.8 to 1. A crosslinked polymer should have a lower conformation slope, typically below about 0.5, such as from about 0 to about 0.4, about 0 to about 0.3, about 0 to about 0.2, or about 0 to about 0.1.
Illustrative, non-limiting examples of cationic polymers of the present disclosure along with their corresponding Huggins constant and conformation plot slope are listed in Table 2.
In some embodiments, the cationic polymer may be crosslinked with the aluminum or iron of the aluminum hydroxide complex or the ferric hydroxide complex. In some embodiments, the cationic polymer has a degree of crosslinking greater than 1%, greater than 2%, greater than 3%, greater than 4%, greater than 5%, greater than 6%, greater than 7%, greater than 8%, greater than 9% or greater than 10%. In certain embodiments, the cationic polymer has a degree of crosslinking less than about 50%, less than about 40%, less than about 30% or less than about 20%. For example, the cationic polymer may have a degree of crosslinking from about 1% to about 50%, from about 5% to about 50%, from about 10% to about 50%, from about 15% to about 50%, from about 20% to about 50%, from about 30% to about 50%, from about 2% to about 25%, from about 2% to about 20%, from about 2% to about 15%, from about 2% to about 10%, from about 3% to about 25%, from about 3% to about 20%, from about 3% to about 15%, from about 3% to about 10%, from about 4% to about 25%, from about 4% to about 20%, from about 4% to about 15% or from about 4% to about 10%.
In some embodiments, the crosslink is formed from an interaction/reaction of an anionic monomer and the iron and/or aluminum. For example, the cationic polymer may comprise a carboxylic acid group and a crosslink may be formed from a reaction/interaction between the carboxylic acid group and the iron and/or aluminum.
An aqueous medium may comprise the colloidal particle (thereby forming an aqueous colloidal composition) and the aqueous medium may have a pH, for example, from about 2 to about 8.5, from about 4.5 to about 8.5, from about 5.5 to about 8.5, from about 6 to about 8.5, from about 5.5 to about 8, from about 6 to about 8 or from about 7 to about 8. In some embodiments, the aqueous medium comprises a pH from about 3.5 to about 8.5. In certain embodiments, the aqueous medium comprises an anionic component. In some embodiments, the colloidal particle is water-insoluble.
In certain embodiments, the colloidal particle is prepared by adding a cationic polymer disclosed herein to an aqueous solvent, such as water, and then adding an aluminum salt and/or ferric salt, and optionally an anionic component, to the solvent. The cationic polymer, metal salt, and optional anionic component can be added continuously, intermittently, and in any order. In some embodiments, the cationic polymer, metal salt, and optional anionic component are co-fed into the solvent.
In some embodiments, the solvent comprises about 0.01 wt. % to about 10 wt. % of the polymer, such as from about 0.01 wt. % to about 9 wt. %, about 0.01 wt. % to about 8 wt. %, about 0.01 wt. % to about 7 wt. %, about 0.01 wt. % to about 6 wt. %, about 0.01 wt. % to about 5 wt. %, about 0.01 wt. % to about 4 wt. %, about 0.01 wt. % to about 3 wt. %, about 0.01 wt. % to about 2 wt. %, or about 0.01 wt. % to about 1 wt. % of the cationic polymer.
In certain embodiments, the solvent comprises from about 0 wt. % to about 1 wt. % of the anionic component, such as from about 0.1 wt. % to about 1 wt. %, about 0.2 wt. % to about 1 wt. %, about 0.3 wt. % to about 1 wt. %, about 0.4 wt. % to about 1 wt. %, about 0.5 wt. % to about 1 wt. %, about 0.6 wt. % to about 1 wt. %, about 0.7 wt. % to about 1 wt. %, about 0.8 wt. % to about 1 wt. %, about 0.9 wt. % to about 1 wt. %, or about 0.3 wt. % to about 0.6 wt. %.
In some embodiments, the solvent comprises a weight ratio of the aluminum salt and/or the ferric salt to the cationic polymer from about 0.05:1 to 100:1. For example, the solvent may comprise a weight ratio of the aluminum salt and/or the ferric salt to the cationic polymer from about 0.1:1, about 0.5:1, about 1:1, about 5:1, about 10:1, about 20:1, about 30:1, about 40:1, about 50:1, about 60:1, about 70:1, about 80:1, or about 90:1. In some embodiments, the solvent comprises more aluminum salt and/or ferric salt than cationic polymer.
As an illustrative example, if a weight ratio of PAC (based on Al2O3) to the cationic polymer was about 1:1, the aluminum ion would be about 159 mol % of the polymer. As an additional, non-limiting example, if a weight ratio of PAC to cationic polymer was about 0.1:1, the aluminum ion would be about 15.9 mol % of the cationic polymer.
The aqueous solvent may have a pH from, for example, about 1.0 to about 6.5 and, after at least some of the polymer and metal salt have been added, the pH may be raised to about 7.0, about 7.5, about 8.0, about 8.5, or higher. In some embodiments, the pH of the composition may be raised by adding a base, such as sodium hydroxide, diluting the composition with water, etc. In certain embodiments, the pH of the composition is raised by adding it to a papermaking process water, wherein a pH of the papermaking process water may be from, for example, about 6.5 to about 8.5. While an amount of colloidal particle may form in the composition before the pH is raised, the substantial majority or all of the colloidal particle forms after the pH is raised.
The colloidal particle has a weight ratio of aluminum hydroxide and/or ferric hydroxide to the cationic polymer from about 0.1:99 to about 99:0.1. For example, the weight ratio may be from about 0.1:50 to about 50:0.1, from about 0.1:25 to about 25:0.1, from about 0.1:10 to about 10:0.1, from about 0.1:5 to about 5:0.1 or from about 0.1:2 to about 2:0.1. In certain embodiments, a weight ratio of the aluminum hydroxide and/or ferric hydroxide to the cationic polymer is from about 0.1:1 to about 2:1. In some embodiments, a weight ratio of the aluminum hydroxide and/or ferric hydroxide to the cationic polymer is from about 0.1:1 to about 0.9:1 or 0.1:1 to about 0.5:1.
The colloidal particle comprises from about 1 wt. % to about 99 wt. % of the cationic polymer. For example, the colloidal particle may comprise from about 5 wt. % to about 99 wt. %, from about 5 wt. % to about 95 wt. %, from about 10 wt. % to about 99 wt. %, or from about 10 wt. % to about 90 wt. % of the cationic polymer.
The colloidal particle comprises from about 1 wt. % to about 99 wt. % of the aluminum hydroxide and/or the ferric hydroxide. For example, the colloidal particle may comprise from about 5 wt. % to about 99 wt. %, from about 5 wt. % to about 95 wt. %, from about 10 wt. % to about 99 wt. %, or from about 10 wt. % to about 90 wt. % of the aluminum hydroxide and/or the ferric hydroxide.
The colloidal particle has an average particle size ranging from about 0.01 to about 1,000 microns. For example, the average particle size may be from about 0.05 to about 100 microns, from about 0.05 to about 80 microns, from about 0.05 to about 60 microns, from about 0.05 to about 40 microns, from about 0.05 to about 20 microns, from about 0.05 to about 10 microns, from about 0.1 to about 50 microns, from about 0.1 to about 40 microns, from about 0.1 to about 30 microns, from about 0.1 to about 20 microns, or from about 0.1 to about 10 microns.
As additional examples, the average particle size may be from about 50 nm to about 500 nm, such as from about 50 nm to about 400 nm, about 50 nm to about 300 nm, about 100 nm to about 200 nm, about 100 nm to about 300 nm, or about 100 nm to about 400 nm.
In some embodiments, the colloidal particle has a zeta potential ranging from about −50 to about +70 mV. For example, the colloidal particle may have a zeta potential ranging from about −40 to about +60, about −30 to about +50, about −20 to about +40, about −10 to about +30, or about 0 to about +30 mV.
In some embodiments, an aqueous composition may comprise at least about 0.01 wt. % of the colloidal particles, based on the dosage of the particles to the aqueous slurry of cellulosic fiber, such as a papermaking furnish.
In some embodiments, the composition comprises greater than 0.01 wt. % of the particles to about 10 wt. % of the particles, such as greater than about 0.02 wt. %, greater than about 0.05 wt. %, greater than about 1 wt. %, greater than about 2 wt. %, or greater than about 3 wt. % to about 5 wt. % of the particles. The percentages in this paragraph refer to the dosage of particles relative to solid fiber dispersed in the furnish.
The compositions and/or particles disclosed herein may include additional papermaking additives including, but not limited to, strength agents, fillers, retention aids, optical brighteners, pigments, sizing agents, starch, dewatering agents, microparticles, coagulants, enzymes, and any combination thereof.
The present disclosure also provides methods of using the presently disclosed compositions, components, and particles in a papermaking process. For example, a composition, component, and/or particle may be added to a papermaking machine, such as to the papermaking furnish or papermaking process water, in order to increase the strength of the resulting paper product.
In some embodiments, a composition comprising the particle is added to the papermaking machine. For example, the cationic polymer may be premixed with a trivalent ion, such as an aluminum salt and/or a ferric salt, in an aqueous medium to form the particle and the resulting mixture may be added to the papermaking machine.
In some embodiments, a composition comprises the cationic polymer and inorganic salt, such as the aluminum salt and/or the ferric salt. This composition may optionally comprise an amount of a colloidal particle as defined herein, such as from about 0 wt. % to about 20 wt. %, about 0 wt. % to about 15 wt. %, about 0 wt. % to about 10 wt. %, about 0 wt. % to about 5 wt. %, or about 0 wt. % to about 1 wt. %, as well as an amount of an anionic component as defined herein.
The composition may be an aqueous composition comprising a pH from about 1 to about 14, such as from about 1 to about 10, from about 1 to about 9, from about 1 to about 8.5, from about 3 to about 14, from about 3 to about 10, from about 3 to about 8.5, from about 3.5 to about 8.5, from about 5 to about 14, from about 5 to about 10 or from about 5 to about 8. In certain embodiments, the composition comprises a pH of about 1 to about 7, such as from about 3 to about 5.
In some embodiments, the composition comprises a weight ratio of the aluminum salt and/or the ferric salt to the cationic polymer from about 0.05:1 to 100:1. For example, the composition may comprise a weight ratio of the aluminum salt and/or the ferric salt to the cationic polymer from about 0.1:1, about 0.5:1, about 1:1, about 5:1, about 10:1, about 20:1, about 30:1, about 40:1, about 50:1, about 60:1, about 70:1, about 80:1, or about 90:1. In some embodiments, the composition comprises more aluminum salt and/or ferric salt than cationic polymer.
In certain embodiments, the composition comprises from about 0.01 wt. % to about 10 wt. % of the cationic polymer. For example, the composition may comprise from about 0.01 wt. % to about 9 wt. %, from about 0.01 wt. % to about 8 wt. %, from about 0.01 wt. % to about 7 wt. %, from about 0.01 wt. % to about 6 wt. %, from about 0.01 wt. % to about 5 wt. %, from about 0.01 wt. % to about 4 wt. %, from about 0.01 wt. % to about 3 wt. %, from about 0.01 wt. % to about 2 wt. %, or from about 0.01 wt. % to about 1 wt. % of the cationic polymer.
In some embodiments, the cationic polymer comprises one or more anionic monomers. The pH of the aqueous composition may be adjusted such that it is greater than the lowest pKa value of a monomer of the cationic polymer. The pKa of an anionic monomer equals the pH value while 50% anionic monomer carries an anionic charge. When the solution pH is higher than the pKa, more anionic charge sites will appear on the cationic polymer chain that can promote its interaction with trivalent ions and their derivatives. If the aqueous composition comprising the cationic polymer is being added separately from the inorganic salt and optionally the anionic component, such as when the cationic polymer, inorganic salt, and/or anionic component are being co-fed, the pH of the aqueous composition comprising the cationic polymer may be adjusted as described herein.
In some embodiments, the cationic polymer and the aluminum salt and/or ferric salt, and optionally the anionic component, are co-fed into a location, such as into a reaction vessel, a storage tank, the papermaking machine, etc. Other components, such as retention aids, dewatering agents, strength aids, etc., may also be co-fed alongside the cationic polymer, anionic component, and/or inorganic salt. In some embodiments when the cationic polymer, inorganic salt, and optional anionic component are co-fed into a location, the particle is formed in the location, such as in a reaction vessel, a storage tank, and/or a papermaking machine, such as in the furnish. In some embodiments, the papermaking process water receiving the cationic polymer, inorganic salt and/or colloidal particle, and optional anionic component, has a near-neutral pH, such as a pH from about 5.5 to about 8.5 or from about 6 to about 8.
For example, an injection pipe may lead to a location in the papermaking furnish and the pipe may inject polymer into the furnish. An adjacent pipe may be present and it may add additional chemical, such as inorganic salt. In certain embodiments, a third pipe, which may also be adjacent to the first and/or second pipes, may add an anionic component. Each chemical addition may be continuous or intermittent, for example. Since the injection pipes are adjacent or substantially adjacent to one another, the chemicals are fed to substantially the same location in the furnish at substantially the same time. The chemicals may interact in the furnish and form a colloidal particle comprising the anionic component.
Thus, in some embodiments, a colloidal particle comprising the anionic component is formed in the furnish or process water and optionally a colloidal particle comprising the anionic component is additionally or alternatively added to the furnish or process water. In some embodiments, a colloidal particle comprising the anionic component may form in a composition before the composition is added to the paper furnish or process water and optionally a colloidal particle comprising the anionic component may form in the furnish or process water.
Any appropriate aluminum salt may be selected and used with the presently disclosed innovation. In some embodiments, the aluminum salt is selected from the group consisting of aluminum chloride, aluminum chloride hydrate, aluminum sulfate, alum, PAC, aluminum chlorohydrate, a compound having the formula AlnCl(3n-m)(OH)m, wherein m is an integer from 0-100, n is an integer from 1-100, and m is less than 3n, and any combination thereof.
Any appropriate ferric salt may be selected and used with the presently disclosed innovation. In some embodiments, the ferric salt is selected from the group consisting of ferric chloride, ferric sulfate, a polyferric salt, and any combination thereof.
The compositions, components, particles, cationic polymers, aluminum salts and/or ferric salts can be added at any location or at any time during a papermaking process. Two, three, or more of the chemicals may be added together and/or two, three, or more of the chemicals may be co-fed into the papermaking machine. For example, the compositions, components, particles, cationic polymers, aluminum salts and/or ferric salts may be added together, separately, and/or co-fed to the thin stock, the thick stock, the headbox, before the headbox, after the headbox, before a press section, and/or any combination of the foregoing locations. The composition, salts, cationic polymers, components, and/or particles can be added to a liquid medium of the papermaking process, such as the process water or furnish.
In some embodiments, the cationic polymer is added to the papermaking process, such as to the furnish, before, after, and/or concurrently with the aluminum and/or ferric salt. The cationic polymer and aluminum and/or ferric salt may be added at the same location and/or at different locations.
In some embodiments, the anionic component (or at least a portion of the anionic component) is added to the papermaking process, such as to the furnish, before, after, and/or concurrently with the cationic polymer, the aluminum and/or ferric salt, and/or the colloidal particle. For example, the cationic polymer (or a portion thereof), aluminum and/or ferric salt (or a portion thereof), and/or the colloidal particle (or a portion thereof) may be added to the papermaking process water followed by the addition of the anionic component (or a portion thereof). The anionic component, cationic polymer, aluminum and/or ferric salt, and/or the colloidal particle may be added at the same location and/or at different locations, in any order.
In some embodiments, a composition comprising any one or more of aluminum salt, ferric salt, cationic polymer, anionic component, and particle is added during a papermaking process, such as to a pulp slurry prior to formation of the paper product. In some embodiments, one or more of the aluminum salt, ferric salt, cationic polymer, anionic component and particle may be added separately into the papermaking process, such as by co-feeding. In certain embodiments, the aluminum and/or ferric salt, the cationic polymer, and optionally the anionic component are premixed prior to addition to the pulp slurry. In other embodiments, the aluminum and/or ferric salt and the cationic polymer are premixed prior to addition to the pulp slurry and subsequently, the anionic component, or a portion thereof, is added to the pulp slurry.
The amount of cationic polymer and aluminum and/or ferric salt added to the papermaking process is not particularly limited. In some embodiments, from about 0.1 to about 100 lb/ton of the aluminum and/or ferric salt, relative to solid fiber, is added to the papermaking machine/process, such as to the pulp slurry. For example, from about 0.1 to about 75 lb/ton, from about 0.1 to about 50 lb/ton, from about 0.1 to about 25 lb/ton, from about 1 to about 30 lb/ton or from about 1 to about 20 lb/ton of the aluminum and/or ferric salt, relative to solid fiber, is added to the papermaking process, such as to the pulp slurry.
In some embodiments, from about 0.1 to about 100 lb/ton of the cationic polymer, relative to solid fiber, is added to the papermaking machine/process, such as to the pulp slurry. For example, from about 0.1 to about 75 lb/ton, from about 0.1 to about 50 lb/ton, from about 0.1 to about 25 lb/ton, from about 1 to about 30 lb/ton or from about 1 to about 20 lb/ton of the cationic polymer, relative to solid fiber, is added to the papermaking process, such as to the pulp slurry.
In some embodiments, from about 0.1 to about 100 lb/ton of the anionic component, relative to solid fiber, is added to the papermaking machine/process, such as to the pulp slurry. For example, from about 0.1 to about 75 lb/ton, from about 0.1 to about 50 lb/ton, from about 0.1 to about 25 lb/ton, from about 1 to about 30 lb/ton or from about 1 to about 20 lb/ton of the anionic component, relative to solid fiber, is added to the papermaking process, such as to the pulp slurry.
The present disclosure also provides methods of improving a papermaking process that include the step of treating a component of the papermaking process with the colloidal particle comprising the anionic component disclosed herein. The term “treating” as used herein refers to contacting, reacting, mixing, or otherwise bringing together the colloidal particle, optionally comprising the anionic component, and the component of the papermaking process.
In some embodiments, the colloidal particle is water-insoluble and has an average particle size ranging from about 0.01 to about 1,000 microns. In some embodiments, the colloidal particle is formed in the absence of paper fibers. For example, the colloidal particle may be formed prior to addition to the papermaking process and contact paper fibers only after formation and addition to the papermaking process.
In some embodiments, all of the anionic component may be added to the colloidal particle prior to addition to the papermaking process water, none of the anionic component may be added to the colloidal particle prior to addition to the papermaking process water, or a portion of the anionic component may be added to the colloidal particle prior to addition to the papermaking process water and a portion of the anionic component may be added to the papermaking process water after the colloidal particle has been added to the papermaking process water.
In certain embodiments, a component of the papermaking process is treated with a colloidal particle comprising the anionic component. In certain embodiments, the component of the papermaking process is located in the papermaking process water, such as the water of the thin stock, thick stock, furnish, pulp slurry, etc., and the particle and anionic component are added to the process water to carry out the “treating” step. In certain embodiments, a cationic polymer and inorganic salt, such as an aluminum salt and/or ferric salt, are added to the process water before, after, and/or with the anionic component. The cationic polymer, salt, and anionic component may be added together in a single composition, may be added separately in any order, and/or may be co-fed into the process water. In these embodiments, all or at least some of the colloidal particles comprising the anionic component are formed in the process water. If the cationic polymer and salt are added together in a single composition, the composition may optionally comprise some colloidal particles.
Any component of the papermaking process may be treated with the compositions and/or particles disclosed herein. In some embodiments, the component to be treated is selected from the group consisting of a fiber, such as a cellulose/pulp fiber, a paper sheet, a paper product, a fines particle, a filler particle, and any combination thereof.
Additionally, the “treating” step can be carried out at one or more locations throughout the papermaking process, such as before the headbox, in the headbox, after the headbox, before a press section, and any combination thereof.
The methods of the present disclosure may be used, for example, to produce a coated fiber, such as a cellulose/pulp fiber, a paper sheet, a paper product, a fines particle, a filler particle, and any combination thereof. In some embodiments, after carrying out a method disclosed herein, a coated pulp fiber may be produced, wherein the pulp fiber comprises a first layer adsorbed onto a surface of the pulp fiber and a second layer disposed on the first layer.
Typically, the first layer is applied by adding the colloidal particle of the present disclosure to the pulp fiber. For example, the colloidal particle may be added to papermaking process water comprising the pulp fiber and the colloidal particle may be adsorbed onto a surface of the pulp fiber. Then, any anionic component of the present disclosure may be added to the papermaking process water. The anionic component may bond to the first layer, thereby forming a second layer on the fiber comprising the anionic component. In some embodiments, at least a portion of the cationic polymer is ionically bonded to at least a portion of the anionic component. In certain embodiments, a paper sheet comprises the fiber.
The foregoing may be better understood by reference to the following examples, which are intended for illustrative purposes and are not intended to limit the scope of the disclosure or its application in any way.
In one experiment, the inventors observed signs of incomplete retention of the colloidal hydroxide complex disclosed herein on the fiber via an increase in the amount of foam in the paper furnish. This indicated that the colloidal hydroxide complex was not performing as efficiently as possible. The inventors hypothesized that the issue could be remedied by adding an anionic component with the colloidal hydroxide complex to the paper furnish. It was considered that such an addition would balance the charge and allow the (net cationic) colloidal hydroxide complex to more effectively adsorb onto the fiber surface.
To test for paper dry strength performance, several anionic components were dosed into a recycled board furnish (at about 2 lb/ton) after addition of about 8 lb/ton of a colloidal aluminum hydroxide complex (CHC), which included a cationic polymer comprising a mole percentage of 8/2/90 methyl chloride quat (MCQ)/AA/AcAm.
One trial included only the colloidal hydroxide complex, which was dosed at about 8 lb/ton. Samples were added to the wet end of the papermaking system (dilute suspension of fiber in water). Sheets were then formed in a handsheet mold, pressed, and dried. The resulting sheets were allowed to equilibrate at about 23° C. and about 50% relative humidity for about 18 hours before strength testing. Strength tests included tensile strength, short span compression strength (SCT or STFI), burst strength, and ring crush strength (RCT).
As can be seen in
Anionic Component 1 was colloidal silica, Anionic Component 2 was a naphthalene sulfonic acid/formaldehyde co-polymer, Anionic Component 3 was an anionic GPAM, Anionic Component 5 was carboxymethyl cellulose, and Anionic Component 6 was a 50 mol % ammonium acrylate acrylic acid polymer.
Further testing was carried out to assess the optimal properties of the anionic component for enhancing the performance of the colloidal hydroxide complex. A series of polyacrylamide-based anionic polymers were made to have the same charge (about 12 mol % acrylic acid) and varying molecular weights, as shown in
Anionic Component 7 was an acrylamide-based polymer comprising about 12 mol % acrylic acid and having a weight average molecular weight of about 210 kDa, Anionic Component 8 was an acrylamide-based polymer comprising about 12 mol % acrylic acid and having a weight average molecular weight of about 510 kDa, and Anionic Component 9 was an acrylamide-based polymer comprising about 12 mol % acrylic acid and having a weight average molecular weight of about 860 kDa.
A similar study was carried out with a variety of anionic components having about the same weight average molecular weight and increasing anionic charge. The results are shown in
The colloidal hydroxide complex was dosed at about 8 lb/ton and the anionic components were dosed at about 6 lb/ton. Anionic Component 10 was an acrylamide-based polymer comprising about 8 mol % acrylic acid and having a weight average molecular weight of about 520 kDa and Anionic Component 11 was an acrylamide-based polymer comprising about 16 mol % acrylic acid and having a weight average molecular weight of about 500 kDa.
Another study was carried out to test the importance of order of addition of the anionic component relative to the colloidal hydroxide complex. The inventors discovered that dosing the anionic component (Anionic Component 4) after the colloidal hydroxide complex provided optimal performance, as can be seen in
One or more of the following protocols, the steps of which are incorporated into the present application in their entirety, can be used to carry out the experiments disclosed in the present application: TAPPI Method T 205—Forming handsheets for physical tests of pulp, TAPPI Method T 220—Physical testing of pulp handsheets, TAPPI Method T 807—Bursting strength, TAPPI Method T 826—Short span compressive strength of containerboard, and TAPPI Method T 822—Ring crush of paperboard (rigid support method).
All of the compositions and methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While this invention may be embodied in many different forms, there are described in detail herein specific preferred embodiments of the invention. The present disclosure is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. In addition, unless expressly stated to the contrary, use of the term “a” is intended to include “at least one” or “one or more.” For example, “a polymer” is intended to include “at least one polymer” or “one or more polymers.”
Any ranges given either in absolute terms or in approximate terms are intended to encompass both, and any definitions used herein are intended to be clarifying and not limiting. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all subranges (including all fractional and whole values) subsumed therein.
Any composition disclosed herein may comprise, consist of, or consist essentially of any element, component and/or ingredient disclosed herein or any combination of two or more of the elements, components or ingredients disclosed herein.
Any method disclosed herein may comprise, consist of, or consist essentially of any method step disclosed herein or any combination of two or more of the method steps disclosed herein.
The transitional phrase “comprising,” which is synonymous with “including,” “containing,” or “characterized by,” is inclusive or open-ended and does not exclude additional, un-recited elements, components, ingredients and/or method steps.
The transitional phrase “consisting of” excludes any element, component, ingredient, and/or method step not specified in the claim.
The transitional phrase “consisting essentially of” limits the scope of a claim to the specified elements, components, ingredients and/or steps, as well as those that do not materially affect the basic and novel characteristic(s) of the claimed invention.
Unless specified otherwise, all molecular weights referred to herein are weight average molecular weights and all viscosities were measured at 25° C. with neat (not diluted) polymers.
As used herein, the term “about” refers to the cited value being within the errors arising from the standard deviation found in their respective testing measurements, and if those errors cannot be determined, then “about” may refer to, for example, within 5%, 4%, 3%, 2%, or 1% of the cited value.
Furthermore, the invention encompasses any and all possible combinations of some or all of the various embodiments described herein. It should also be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.
| Number | Date | Country | |
|---|---|---|---|
| 63483205 | Feb 2023 | US |
