Patent Application
20250188681
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 and water resistance.
In the papermaking industry, sizing technology is commonly utilized to make paper having water resistance by manipulating the internal sizing and paper surface sizing of the paper. Internal sizing methods commonly involve adding a sizing agent, such as alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), or rosin size, directly to a paper furnish. In general, particles of the sizing agent are capable of forming larger agglomerates, which are adsorbed onto the surfaces of the fibers and fillers of the paper furnish. These particles are generally retained in the wet paper sheet and in the drying section. Influenced by drying temperature, the particles of the sizing agent generally melt and spread onto the fiber surface. Reactive functional groups of the sizing agent direct inward toward the fibers and hydrophobic groups of the sizing agent direct outward away from the fibers. The reactive functional groups react with a hydroxyl group of the cellulose of the fiber, forming a covalent bond and resulting in sizing of the paper.
The present disclosure provides compositions and methods for improving papermaking processes. In some embodiments, a method of improving a papermaking process comprises adding a colloidal particle to a papermaking process water of a papermaking machine, the colloidal particle comprising a polymer embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex, and adding a sizing agent to the papermaking process water, wherein the papermaking process water comprises a recycled fiber and/or a virgin fiber.
In some embodiments, a composition of the present disclosure comprises a colloidal particle comprising a polymer embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex, a sizing agent, and a papermaking process water comprising a recycled fiber.
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 (e.g., colloidal particle and sizing agent), 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, two components, such as a polymer and an inorganic salt, 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 improving sizing agent performance as well as water resistance and/or strength of a paper product. The compositions, which may be aqueous compositions, include a sizing agent and colloidal particle, which may be interchangeably referred to as a “particle” throughout the present disclosure. The particle comprises a polymer embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex.
It has been surprisingly found that the particle significantly improved the performance of the sizing agent disclosed herein. In accordance with the present disclosure, the sizing agent may comprise, for example, an AKD, rosin, an ASA, and any combination thereof. Before adding the sizing agent to papermaking process, the sizing agent may optionally be emulsified with an emulsifying agent, such as cationic starch, to form an aqueous sizing agent emulsion.
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 before, after, and/or with the sizing agent. 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 polymer of the present disclosure, before addition to the papermaking machine because it would be expected that the polymer would interfere with the charged scavenger and destroy its intended function.
The 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 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.
In some embodiments, the polymer has a net negative charge and in other embodiments, the polymer has a net positive charge or a neutral charge. In certain embodiments, the polymer is water-soluble. In some embodiments, the polymer comprises a carboxylic acid group.
For example, the 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 %.
In some embodiments, the 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 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, 2-acrylamido-2-methylpropane sulfonic acid (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 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 polymer comprises a glyoxalated polyacrylamide (GPAM), a polyvinylamine (PVAM), a polyethylenimine (PEI), a polyamidoamine epichlorohydrin (PAE), or any combination thereof.
Additional examples of 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 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 polymer is not particularly limited. In some embodiments, the polymer comprises from about 1 mol % to about 99 mol % of the cationic monomer. For example, the 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 cationic monomer.
In some embodiments, the polymer comprises from about 1 mol % to about 99 mol % of the anionic monomer. For example, the 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 an anionic monomer.
In some embodiments, the polymer comprises from about 1 mol % to about 99 mol % of a non-ionic monomer. For example, the 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 polymer comprises from about 1 mol % to about 99 mol % of a zwitterionic monomer. For example, the 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 polymer disclosed herein comprises from about 1 mol % to about 10 mol % of the cationic monomer and about 1 mol % to about 5 mol % of the anionic monomer. For example, the polymer may comprise from about 5 mol % to about 10 mol % of the cationic monomer, such as about 6 mol %, about 7 mol %, about 8 mol %, or about 9 mol % of the cationic monomer, and about 1 mol %, about 2 mol %, about 3 mol %, about 4 mol %, or about 5 mol % of the anionic monomer.
In some embodiments, the polymer is not a disaccharide or a polysaccharide. In certain embodiments, the polymer excludes monosaccharide monomers. In certain embodiments, the composition or particle disclosed herein excludes a polysaccharide, an anionic polysaccharide, and/or pulp fibers, while in other embodiments, a composition or particle disclosed herein may comprise a polysaccharide, an anionic polysaccharide, and/or pulp fibers. In some embodiments, the polymer excludes a hydroxamic acid group, an isocyanate group, N-bromoamine and/or N-chloroamine. In certain embodiments, the polymer comprises unmodified/unreacted amide and/or amine side chains. In some embodiments, if the polymer 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 polymer is embedded within a colloidal aluminum hydroxide complex and/or a colloidal ferric hydroxide complex.
In some embodiments, a polymer of the present disclosure is a water-soluble amphoteric polymer containing a carboxylic acid group. In certain embodiments, a polymer of the present disclosure may be linear, branched, crosslinked, structured, synthetic, semi-synthetic, natural, and/or functionally modified. A 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 polymer is not particularly limited. In some embodiments, the polymer has a molecular weight ranging from about 10,000 Da to about 10,000,000 Da. For example, the 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 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 polymer of the present disclosure comprises a Huggins constant of about 0.0 to about 1.0. For example, the Huggins constant of a 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; n0=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 n and no are measured using a Cannon Ubbelohde semimicro dilution viscometer, size 75.
In the SEC/MALLS analysis of the present disclosure, the polymer solution was diluted with an aqueous mobile phase (0.3M NaCl, 0.1M 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 polymer provides more dry strength than a crosslinked polymer when complexed with a metal salt, such as PAC. Linearity of the polymer can be defined using Huggins constant, with a lower Huggins constant indicating a more linear polymer.
Certain polymers disclosed herein may have a conformation plot slope of about 0.05 to about 1.0. For example, the 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 polymers of the present disclosure along with their corresponding Huggins constant and conformation plot slope are listed in Table 2.
In some embodiments, the polymer may be crosslinked with the aluminum or iron of the aluminum hydroxide complex or the ferric hydroxide complex. In some embodiments, the 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 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 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 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 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 some embodiments, the colloidal particle is water-insoluble.
In certain embodiments, the colloidal particle is prepared by adding a polymer disclosed herein to an aqueous solvent, such as water, and then adding an aluminum salt and/or ferric salt to the solvent. The polymer and metal salt can be added continuously, intermittently, and in any order. In some embodiments, the polymer and metal salt 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 polymer.
In some embodiments, the solvent comprises a weight ratio of the aluminum salt and/or the ferric salt to the 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 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 polymer.
As an illustrative example, if a weight ratio of PAC (based on Al2O3) to the 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 polymer was about 0.1:1, the aluminum ion would be about 15.9 mol % of the 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 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 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 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 polymer. For example, the colloidal particle may comprise form 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 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 form 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, starch, dewatering agents, microparticles, coagulants, enzymes, and any combination thereof.
As an illustrative example, a composition of the present disclosure may comprise a colloidal particle and a polysaccharide (e.g., starch) and/or a composition of the present disclosure may comprise a sizing agent and a polysaccharide. Additionally or alternatively, when carrying out methods disclosed herein, a polysaccharide may be added before, after, and/or with the colloidal particle and/or the sizing agent.
The present disclosure also provides methods of using the presently disclosed compositions, particles, and/or sizing agents in a papermaking process. For example, a particle (or composition comprising the particle) may be added to a papermaking machine, such as to the papermaking furnish or papermaking process water, before, after, and/or with a sizing agent to increase the performance of the sizing agent and optionally 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 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 before, after, and/or with the sizing agent.
In some embodiments, a composition comprises the 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. %.
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 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 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 polymer.
In certain embodiments, the composition comprises from about 0.01 wt. % to about 10 wt. % of the 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 polymer.
In some embodiments, the 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 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 polymer chain that can promote its interaction with trivalent ions and their derivatives.
In some embodiments, the particle and the sizing agent 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 particle and/or sizing agent.
In some embodiments, the papermaking process water receiving the particle and sizing agent 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 the particle into the furnish. An adjacent pipe may be present and it may add additional chemical, such as a sizing agent. 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.
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 ClnCl(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, compounds, components, particles, polymers, aluminum salts and/or ferric salts can be added at any location or at any time during a papermaking process. Two or more of the components may be added together and/or two or more components may be co-fed into the papermaking process water. For example, the compositions, compounds, components, particles, 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, in a size press, and/or any combination of the foregoing locations. The compositions, compounds, components, salts, polymers, and/or particles can be added to a liquid medium of the papermaking process, such as the furnish.
In some embodiments, the colloidal particle is added to the papermaking process, such as to the furnish, before, after, and/or concurrently with the sizing agent. The colloidal particle and sizing agent may be added at the same location and/or at different locations.
In some embodiments, a composition comprising a colloidal particle is added during a papermaking process, such as to a pulp slurry prior to formation of the paper product. In some embodiments, a sizing agent may be added separately into the papermaking process, such as by co-feeding. In certain embodiments, the colloidal particle and the sizing agent may be premixed prior to addition to the process water (e.g., furnish).
The amount of the colloidal particle added to the papermaking process water is not particularly limited. In some embodiments, from about 0.1 to about 20 lb/ton of the colloidal particle, relative to solid fiber, is added to the papermaking process water, such as to the pulp slurry. For example, from about 0.1 to about 18 lb/ton, from about 0.1 to about 16 lb/ton, from about 0.1 to about 14 lb/ton, from about 0.1 to about 12 lb/ton, from about 0.1 to about 10 lb/ton, from about 0.1 to about 8 lb/ton, from about 0.1 to about 6 lb/ton, from about 0.1 to about 4 lb/ton, from about 0.1 to about 2 lb/ton, or from about 0.1 lb/ton to about 1 lb/ton of the colloidal particle, relative to solid fiber, is added to the papermaking process water, such as to the pulp slurry.
The amount of the sizing agent added to the papermaking process water is not particularly limited. In some embodiments, from about 0.1 to about 20 lb/ton of the sizing agent, relative to solid fiber, is added to the papermaking process water, such as to the pulp slurry. For example, from about 0.1 to about 18 lb/ton, from about 0.1 to about 16 lb/ton, from about 0.1 to about 14 lb/ton, from about 0.1 to about 12 lb/ton, from about 0.1 to about 10 lb/ton, from about 0.1 to about 8 lb/ton, from about 0.1 to about 6 lb/ton, from about 0.1 to about 4 lb/ton, from about 0.1 to about 2 lb/ton, or from about 0.1 lb/ton to about 1 lb/ton of the sizing agent, relative to solid fiber, is added to the papermaking process water, 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 and the sizing agent disclosed herein. The term “treating” as used herein refers to contacting, reacting, mixing, or otherwise bringing together the colloidal particle, the sizing agent, and the component. As noted throughout the present disclosure, the colloidal particle is formed from mixing a polymer and an aluminum salt and/or ferric salt. 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 certain embodiments, a component of the papermaking process is treated with a colloidal particle and sizing agent. In certain embodiments, the component 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/or sizing agent is added to the process water to carry out the “treating” step. The colloidal particle and sizing agent 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.
Any component of the papermaking process may be treated with the compositions, components (e.g., a sizing agent), compounds, and/or colloidal particles disclosed herein. In some embodiments, the component to be treated is selected from the group consisting of a fiber, such as a cellulose fiber (e.g., virgin fiber and/or recycled fiber), a paper sheet, a paper product, a fines particle, a filler particle, a pulp, and any combination thereof.
In accordance with the present disclosure, the term “recycled fiber” includes post-consumer fiber, recovered fiber, and/or mill broke, as defined by the U.S. Environmental Protection Agency (EPA). The EPA defines a “virgin fiber” as a cellulose fiber derived directly from trees and other plants that is newly pulped and previously unused.
The “treating” step of the methods disclosed herein 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, in a size press, and any combination thereof.
The colloidal particle may comprise any one or more of the polymers disclosed herein, such as a polymer comprising a monomer selected from the group consisting of an anionic monomer, a cationic monomer, a non-ionic monomer, a zwitterionic monomer, and any combination thereof.
As noted throughout the present disclosure, the colloidal particle has an average particle size ranging from about 0.1 to about 1,000 microns.
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.
The following examples show that when the colloidal particle disclosed herein is dosed with a sizing agent, a significant and unexpected increase in the sizing response of the sheet is obtained. The colloidal particle itself is not believed to provide any water resistance (sizing) to the sheet but instead acts synergistically with the sizing agent. While use of the colloidal particle has been shown to improve retention within a papermaking system, the increase in sizing response cannot be explained by an improvement in retention of the sizing agent alone.
In one experiment, Product 1 (octadecenyl succinic anhydride, hexadecenyl succinic anhydride, mixed C15-C20 olefins, phosphoric acid ester) was emulsified with Product 2 (water, acrylamide-modified with DMAEM.MCQ, phosphoric acid ester) at a 1:1 product ratio. The colloidal particle was dosed into a recycled board furnish (lab OCC) either before or after the ASA additive (about ten seconds separated the two components added to the furnish).
In another experiment, Product 1 and Product 2 were tested once again. The components of the colloidal particle (e.g., the polyampholyte and the PAC), as well as the colloidal particle itself, were dosed before the ASA additive in a lab OCC and the sizing response was measured. The results are shown in
A study was also carried out using a recycled board furnish from a paper mill. In this study, Product 3 was used, which was a combination of 1) C15-C20 alkenyl succinic anhydride, mixed C15-C20 olefins and 2) about 12 mol % cationic (DADMAC)glyoxalated polyacrylamide (GPAM), along with the colloidal particle. The sizing results from this study are shown in
Additional studies investigating the impact of the colloidal particle on sizing were performed in a simulated gypsum furnish. Here, no impact to sizing was observed with the colloidal particle. While the colloidal particle provides significant strength in both OCC and gypsum furnishes, the sizing improvement was only observed in OCC furnishes.
The gypsum furnish was prepared by mixing about 50/50 OCC/newsprint. Newsprint includes a groundwood mechanical fiber. Although not wishing to be bound by theory, the present inventors believe the groundwood mechanical fiber interferes with the sizing improvement mechanism, but not the strengthening mechanism.
One or more of the following methods may have been carried out in connection with the examples disclosed herein. The steps of the following methods are hereby incorporated by reference in their entirety into 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 530-Size test for paper by ink resistance, 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 | |
|---|---|---|---|
| 63608074 | Dec 2023 | US |
