EP1092064B9 - Method for making paper and cardboard - Google Patents
Method for making paper and cardboard Download PDFInfo
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- EP1092064B9 EP1092064B9 EP99923647A EP99923647A EP1092064B9 EP 1092064 B9 EP1092064 B9 EP 1092064B9 EP 99923647 A EP99923647 A EP 99923647A EP 99923647 A EP99923647 A EP 99923647A EP 1092064 B9 EP1092064 B9 EP 1092064B9
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- Prior art keywords
- emulsion
- polymer
- branched
- process according
- water
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
- D21H23/04—Addition to the pulp; After-treatment of added substances in the pulp
- D21H23/06—Controlling the addition
- D21H23/14—Controlling the addition by selecting point of addition or time of contact between components
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
- D21H21/06—Paper forming aids
- D21H21/10—Retention agents or drainage improvers
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
- D21H23/76—Processes or apparatus for adding material to the pulp or to the paper characterised by choice of auxiliary compounds which are added separately from at least one other compound, e.g. to improve the incorporation of the latter or to obtain an enhanced combined effect
- D21H23/765—Addition of all compounds to the pulp
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/20—Macromolecular organic compounds
- D21H17/33—Synthetic macromolecular compounds
- D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D21H17/37—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/63—Inorganic compounds
- D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
- D21H17/68—Water-insoluble compounds, e.g. fillers, pigments siliceous, e.g. clays
Definitions
- the present invention relates to the technical sector of papermaking.
- the invention relates to a method for the production of paper or cardboard retention, and other properties, improved.
- bentonite to the paste, which may optionally be added to other mineral products, such as aluminum sulphates, or even synthetic polymers, in particular polyethylene imine (see for example documents DE-A-2,262,906 and US-A-2,368,635 ).
- EP 0 574 335 a a major improvement by proposing the use of polymers (especially polyacrylamides) branched in the form of a powder.
- the invention overcomes the disadvantages mentioned above.
- This method makes it possible to obtain a markedly improved retention of fines and fillers without any reverse effect.
- An additional feature of this improvement is also improved the dewatering properties.
- the branched polyacrylamide (or more generally the branched (co) polymer) is introduced into the suspension, very preferably, in the form of a water-in-oil inverse emulsion, at a rate of 0.03 to one per thousand. (0.03 to 1% o, ie 30 to 1000 g / t) by weight of active ingredient (polymer) relative to the dry weight of the fibrous suspension, preferably from 0.15 to 0.5 per thousand, ie 150 at 500 g / t.
- the inverse polymer emulsion is diluted with water and inverted (solubilized) by this dilution before its introduction, as described above.
- the polymer is prepared by water-in-oil inverse emulsion polymerization.
- this polymer can then be used (ie injected or introduced into the mass or paste to be flocculated) either in the form - preferably - of this inverse emulsion after its dissolution in water, or in the form of a powder obtained by drying (in particular by spray-drying or "spray-drying") of the inverse emulsion of the polymerization, and then redissolving this powder in water, for example at a concentration of the order of 5 g of active polymer / liter, the solution thus obtained being then injected into the dough at substantially the same polymer dosages.
- the branched (co) polyacrylamide is a cationic copolymer of acrylamide and an unsaturated cationic ethylenic monomer selected from the group comprising dimethylaminoethyl acrylate (ADAME), dimethylaminoethyl methacrylate (MADAME), quaternized or salified by different quaternizing acids and agents, benzyl chloride, methyl chloride, alkyl- or aryl chlorides, dimethyl sulphate, dimethyldiallylammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (APTAC), and methacrylamidopropyltrimethylammonium chloride (MAPTAC),
- ADAME dimethylaminoethyl acrylate
- MADAME dimethylaminoethyl methacrylate
- benzyl chloride methyl chloride, alkyl- or aryl chlorides, dimethyl sulphate, dimethyldially
- this copolymer is branched by a branching agent consisting of a compound having at least two reactive groups selected from the group comprising double bonds, aldehyde bonds or epoxy bonds.
- branching agent consisting of a compound having at least two reactive groups selected from the group comprising double bonds, aldehyde bonds or epoxy bonds.
- a branched polymer is a polymer which has branches, groups or branches on the chain which are generally arranged in a plane and not in the three directions, unlike a crosslinked polymer ( "Cross-linked”); such branched, high molecular weight polymers are well known as flocculants.
- Crosslinked polymer "Cross-linked”
- These branched polyacrylamides are distinguished from the crosslinked polyacrylamides in that in the latter, the groups are arranged three-dimensionally to give substantially insoluble products of infinite molecular weight.
- the branching may preferably be carried out during (or possibly after) the polymerization, for example by reaction of two soluble polymers having counterions, or by reaction with formaldehyde or a polyvalent metal compound. Often, the branching takes place during the polymerization by addition of a branching agent, and this solution will be clearly preferred according to the invention. These branching polymerization processes are well known.
- Branching agents which can be incorporated include ionic branching agents such as polyvalent metal salts, formaldehyde, glyoxal, or preferably covalent crosslinking agents which will copolymerize with the monomers, preferably diethylenically unsaturated monomers (such as the family of diacrylate esters such as PEG polyethylene glycol diacrylates) or polyethylene, of the type conventionally used for the crosslinking of water-soluble polymers, and in particular methylenebisacrylamide (MBA) or any of the other known acrylic branching agents.
- ionic branching agents such as polyvalent metal salts, formaldehyde, glyoxal, or preferably covalent crosslinking agents which will copolymerize with the monomers, preferably diethylenically unsaturated monomers (such as the family of diacrylate esters such as PEG polyethylene glycol diacrylates) or polyethylene, of the type conventionally used for the crosslinking of water-soluble polymers, and in particular methylenebis
- crosslinking agents are often identical to the crosslinking agents, but the crosslinking can be avoided, when it is desired to obtain a branched and not crosslinked polymer, by an optimization of the polymerization conditions such as concentration during the polymerization, type and amount of polymerization. transfer agent, temperature, type and amount of initiators, and the like.
- the branching agent is methylenebisacrylamide (MBA), introduced at a rate of five to two hundred (5 to 200) moles per million moles of monomers, preferably 5 to 50 moles.
- MBA methylenebisacrylamide
- the amount of branched polyacrylamide introduced into the suspension to be flocculated is between thirty and thousand grams of active polymer / tonne of dry pulp (30 and 1000 g / t), or between 0.03 per thousand and one per thousand, of preferably from 150 to 500 g / t; it has been observed that if the amount is less than 0.03% o (0.03 per thousand), no significant retention is obtained; likewise, if this quantity exceeds 1% o (1 per thousand), no proportional improvement is observed; however, unlike linear cationic polyacrylamides, as described in the documents EP-A-0 017 353 and EP 0 235 893 referred to in the preamble, there is no reverse effect of dispersion by recirculation in the closed circuits of the excess polymer not retained on the sheet.
- the amount of branched polyacrylamide introduced is between 0.15 and 0.5 per thousand (0.15 and 0.5% o) of the quantity of the dry pulp, ie between 150 g / t and 500
- the branched polymer be prepared as an inverse emulsion (water-in-oil) to achieve the improvement of the invention.
- emulsions and their method of preparation are well known to those skilled in the art.
- the invention was all the more difficult to realize that it is important to remain in the field of branched polymers and not to go into the field of crosslinked polymers.
- the border between the two zones is very easily crossed, in fact irreversibly.
- the difficulty of developing the invention is measured, and it is the Claimant's merit that it has tackled the use of this technology in the field of manufacturing the paper, which poses particular problems and presents very stringent quality requirements.
- the branched powdered polymers of the aforementioned EP 0 574 335 had already made significant progress with regard to the properties and the papermaking process.
- the improvement was of the order of 20 to 40% depending on the properties.
- a “moderately branched" polymer for example 10 ppm branching with respect to the active material, will be used in a preferred manner, but not limited to.
- the polymer either in the form of its synthetic inverse emulsion, dissolved or "inverted” in water, or in the form of the solution in the water of the powder obtained by drying the said synthetic emulsion, in particular by spray drying.
- Spray drying is a method also known to those skilled in the art. Refer to the tests below to verify that the results are comparable.
- Bentonite also called “swelling smectic clay", of the montmorillonite family, is well known and there is no need to describe it here in detail; these compounds, formed of microcrystallites, have on the surface sites with a high cation exchange capacity that can retain water (see for example document US-A-4,305,781 , which corresponds to the document EP-A-0 017 353 , mentioned above, and the FR-A-2,283,102 ).
- a semi-sodium bentonite which is introduced just upstream of the headbox, is preferably used at a rate of 0.1 to 0.5 percent (0.1 to 0.5%) of the dry weight of the fibrous suspension.
- filler use may be kaolins, ground “GCC” or CaCO3, precipitated CaCO3 or "PCC”, and the like.
- Injection or introduction of the branched polymer in inverse emulsion is carried out before a shearing step in the paper pulp (or fibrous mass to be flocculated) more or less diluted according to the practice of the person skilled in the art, and generally in the pulp.
- thin paper ie a pulp diluted to about 0.7 - 1.5% solids such as cellulose fibers, optional fillers, and the various conventional papermaking additives.
- fractionally introduced will be introduced a portion of the emulsion branched polymer, according to the invention, at the stage of preparation of the thick paste or "thick stock” to approx. 5% or more solids, or even in the preparation of the thick slurry before a shear step.
- the UL viscosity results are as follows:
- EM140CT standard emulsion of very high molecular weight containing no branching agent.
- EM140L standard high molecular weight emulsion containing no branching agent.
- EM140LH Medium molecular weight emulsion containing no branching agent.
- EM140BD crosslinked emulsion containing no transfer agent and 5 ppm crosslinking agent.
- SD 102 spray-dried emulsion R 102, and powder obtained dissolved in water at 5 g of active polymer / liter.
- the paste used is diluted to a consistency of 1.5%. 2.24 g of pulp are taken, ie 149 g of pulp at 150% and then diluted to 0.4% with clear water.
- the crosslinked polymers 1, 4, 9, 12 are not of interest for the flocculation and retention of fines and fillers despite the high rate of shear applied during processing on the fibrous mass (and not applied to the polymer itself), here 1500 rpm, which is characteristic of this type of microparticulate retention system. They show a low capture of the charges and colloidal materials because no reduction of turbidity is observed.
- the combination with bentonite does not significantly improve retention efficiency and only slightly improves drainage efficiency.
- the combination according to the invention of a branched polymer in inverse emulsion and bentonite provides a net gain in charge retention and total retention, and is found to be superior to the known linear polymer / bentonite system.
- the coagulation power is higher for a branched polymer in emulsion, which results in an excellent reduction of the turbidity at 30 '(30 min.).
- the R 52 test and the R 102 test show that the invention makes it possible to obtain branched products having higher UL viscosities than those accessible by a gel polymerization as described in US Pat. EP 0 574 335 (FO 4198). Any attempt to achieve such highly advantageous UL viscosity values by a powdered gel polymerization route would result in a product that is completely insoluble and therefore totally unusable in the industry.
- Test SD 102 shows that the polymer used in the form of a solution in the water of the powder obtained by drying the inverse emulsion of the synthesis of the polymer behaves as the polymer used in the form of the solution in the water of said synthesis inverse emulsion. In particular, there is no degradation of the polymer during the spray drying step.
- test R 52 can be usefully compared to the test FO 4198 (powder) because the polymers have the same chemistry, therefore the same cationicity, and the same% MBA, while the R 52 used according to the invention is very higher than the powder in terms of dripping and retention (96.3 to be closer to 83.6); the NTU turbidity will also be compared after 30 minutes. , of 32 compared to 75 NTU units.
- the invention therefore relates to a method for producing a sheet of paper or cardboard or the like, using a retention agent, which consists of an acrylic (co) polymer as described above, branched, in inverse emulsion, and which is characterized in that its UL viscosity is> 3, or> 3.5 or> 4.
- Said agent can be used either in inverted emulsion with water, or in solution of the powder obtained by drying the emulsion, as described above.
- the contents of B are mixed in A with stirring. After mixing the phases, the emulsion is sheared for 1 minute in order to create the inverse emulsion. The emulsion is then degassed by bubbling nitrogen and after 20 minutes, the gradual addition of metabisulfite leads to initiation and then polymerization.
- the emulsion is then incorporated with its reversing surfactant in order subsequently to release the polymer in the aqueous phase.
- the invention relates to a method for producing a sheet of paper or cardboard or the like employing retention agents described above, characterized in that they consist of, or comprise, at least one (co) polymer of the type described, branched, prepared in inverse emulsion, intended to cooperate with a secondary retention agent after an intermediate step of shearing the paper pulp, as well as processes for producing sheets of paper, cardboard or the like, using the agents described above in the process according to the invention, and the sheets of paper, cardboard and the like thus obtained.
- retention agents described above consist of, or comprise, at least one (co) polymer of the type described, branched, prepared in inverse emulsion, intended to cooperate with a secondary retention agent after an intermediate step of shearing the paper pulp, as well as processes for producing sheets of paper, cardboard or the like, using the agents described above in the process according to the invention, and the sheets of paper, cardboard and the like thus obtained.
- Said agent may be used either in inversion emulsion with water, or in solution of the powder obtained by drying the emulsion, as described above.
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Abstract
Description
La présente invention concerne le secteur technique de la fabrication du papier.The present invention relates to the technical sector of papermaking.
L'invention concerne un procédé pour la fabrication d'un papier ou d'un carton à rétention, et autres propriétés, améliorées.The invention relates to a method for the production of paper or cardboard retention, and other properties, improved.
Lors de la fabrication du papier, du carton ou analogue, il est bien connu d'introduire dans la pâte des agents de rétention dont la fonction est de retenir un maximum de fines et de charges dans la feuille. Les effets bénéfiques qui découlent de l'utilisation d'un agent de rétention sont essentiellement :
- l'augmentation de la production et la diminution des coûts de fabrication : économie énergétique, marche plus régulière de la machine, rendement plus élevé en fibres, fines, charges et de produits d'ennoblissement anioniques, plus faible acidité dans le circuit liée a une diminution de l'utilisation de sulfate d'alumine et donc amoindrissement des problèmes de corrosion ;
- l'amélioration de la qualité : meilleure formation et meilleur épair ; amélioration du taux d'humidité de la feuille, de l'opacité, du lisse, du pouvoir absorbant et diminution de la porosité du papier.
- increased production and lower manufacturing costs: energy saving, more regular machine operation, higher yield of fibers, fines, fillers and anionic finishing products, lower acidity in the circuit related to reduction in the use of alumina sulphate and thus lessening of corrosion problems;
- quality improvement: better training and better looking; improvement of the leaf moisture content, opacity, smoothness, absorbency and decrease of paper porosity.
Depuis longtemps, on a proposé d'ajouter a la pâte de la bentonite, celle-ci pouvant être éventuellement additionnée à d'autres produits minéraux, tels que des sulfates d'aluminium, voire des polymères synthétiques, notamment du polyéthylène-imine (voir par exemple documents
Dans le document
Dans le document
Dans le document
Dans les notes présentées à l'occasion de cours à Seattle, 11-13 octobre 1989, et publiées sous le titre "Supercoagulation in the control of wet end chemistry by synthetic polymer and activated bentonite", R. Kajasvirta a décrit le mécanisme de la supercoagulation de la bentonite activée en présence d'un copolyacrylamide cationique, sans en préciser la nature exacte. Ce procédé présente les mêmes inconvénients que précédemment.In notes presented at the course of lectures in Seattle, October 11-13, 1989, and published under the title "Supercoagulation in the control of wet end polymer by polymer and activated bentonite", R. Kajasvirta described the mechanism of the supercoagulation of the activated bentonite in the presence of a cationic copolyacrylamide, without specifying the exact nature thereof. This process has the same disadvantages as before.
Enfin, le
L'invention pallie les inconvénients rappelés ci-dessus.The invention overcomes the disadvantages mentioned above.
Elle vise un procédé perfectionné du type en question, qui consiste à ajouter, à la suspension ou masse fibreuse ou pâte à papier à floculer, comme agent de rétention principal, un agent qui consiste en, ou comprend, un polyacrylamide ramifié selon la revendication 1 et comme décrit a été préparé en émulsion inverse ou eau-dans-huile, et de la bentonite comme second agent de rétention (système dit « dual », de type dit également « microparticulaire »).It relates to an improved process of the type in question, which consists in adding, to the suspension or fibrous mass or paper stock to be flocculated, as main retention agent, an agent which consists of, or comprises, a branched polyacrylamide according to
Par le vocable « se présente en émulsion inverse » ou des vocables analogues, se rapportant au polymère utilisé (cad tel qu'injecté ou introduit dans la pâte à floculer) selon l'invention, l'homme de métier comprendra que l'on désigne l'émulsion inverse eau-dans-huile qui est dissoute dans l'eau avant son injection ou son introduction dans la masse ou pâte à floculer (cette dissolution dans l'eau provoque ce que l'on nomme l'« inversion » de l'émulsion inverse eau-dans-huile initiale; ces procédés sont bien connus de l'homme de métier).By the term "is in inverse emulsion" or similar terms, referring to the polymer used (ie as injected or introduced into the flocculant paste) according to the invention, the skilled person will understand that we designate the water-in-oil inverse emulsion which is dissolved in the water before its injection or its introduction into the mass or paste to be flocculated (this dissolution in the water causes what is called the "inversion" of the initial water-in-oil emulsion, these processes are well known to those skilled in the art).
Les additions du polymère et de la bentonite sont séparées par une étape de cisaillement, par exemple au niveau de la pompe de mélange dite « fan pump ». On se référera dans ce domaine à la description du
On se référera également au
Il est possible de remplacer la bentonite, comme agent de rétention secondaire, par un kaolin tel que décrit dans la demande de
Ce procédé permet d'obtenir une rétention nettement améliorée de fines et de charges et ce sans effet inverse. On améliore également, ce qui est une caractéristique supplémentaire de ce perfectionnement, les propriétés d'égouttage.This method makes it possible to obtain a markedly improved retention of fines and fillers without any reverse effect. An additional feature of this improvement is also improved the dewatering properties.
Le polyacrylamide ramifié (ou plus généralement le (co)polymère ramifié) est introduit dans la suspension, de manière tout à fait préférée, sous la forme d'émulsion inverse eau-dans-huile , à raison de 0,03 à un pour mille (0,03 a 1 %o, soit 30 à 1000 g/t) en poids de matière active (polymère) par rapport au poids sec de la suspension fibreuse, de préférence de 0,15 à 0,5 pour mille, soit 150 à 500 g/t.The branched polyacrylamide (or more generally the branched (co) polymer) is introduced into the suspension, very preferably, in the form of a water-in-oil inverse emulsion, at a rate of 0.03 to one per thousand. (0.03 to 1% o, ie 30 to 1000 g / t) by weight of active ingredient (polymer) relative to the dry weight of the fibrous suspension, preferably from 0.15 to 0.5 per thousand, ie 150 at 500 g / t.
De manière connue de l'homme de métier, l'émulsion inverse de polymère est diluée à l'eau et inversée (solubilisée) par cette dilution avant son introduction, comme décrit plus haut.In a manner known to those skilled in the art, the inverse polymer emulsion is diluted with water and inverted (solubilized) by this dilution before its introduction, as described above.
Cette sélection de la forme émulsion inverse permet, dans l'application papetière pour la rétention de charges et de fines, d'atteindre un niveau de performances inégalé jusqu'alors. L'utilisation de polymères ramifiés permet de plus de mieux retenir la bentonite sur la feuille, comme décrit dans le brevet
On comprendra qu'il est essentiel selon l'invention que le polymère soit préparé par une polymérisation en émulsion inverse eau-dans-huile. Par contre, ce polymère peut ensuite être utilisé (cad injecté ou introduit dans la masse ou pâte à floculer) soit sous la forme - de préférence - de cette émulsion inverse après sa dissolution dans de l'eau, soit sous la forme d'une poudre obtenue par séchage (notamment par séchage par pulvérisation ou « spray-drying ») de l'émulsion inverse de la polymérisation, puis redissolution de cette poudre dans de l'eau, par exemple à une concentration de l'ordre de 5 g de polymère actif / litre, la solution ainsi obtenue étant alors injectée dans la pâte sensiblement aux mêmes dosages de polymère.It will be understood that it is essential according to the invention that the polymer is prepared by water-in-oil inverse emulsion polymerization. On the other hand, this polymer can then be used (ie injected or introduced into the mass or paste to be flocculated) either in the form - preferably - of this inverse emulsion after its dissolution in water, or in the form of a powder obtained by drying (in particular by spray-drying or "spray-drying") of the inverse emulsion of the polymerization, and then redissolving this powder in water, for example at a concentration of the order of 5 g of active polymer / liter, the solution thus obtained being then injected into the dough at substantially the same polymer dosages.
Le (co)polyacrylamide ramifié est un copolymère cationique d'acrylamide et d'un monomère éthylénique cationique non saturé, choisi dans le groupe comprenant l'acrylate de dimethylaminoethyl (ADAME), le methacrylate de dimethylaminoethyle (MADAME), quaternisés ou salifiés par différents acides et agents quaternisants, benzyle chlorure, méthyle chlorure, alkyl- ou aryle chlorures, diméthylsulfate, le chlorure de dimethyldiallylammonium (DADMAC), le chlorure d'acrylamidopropyltrimethylammonium (APTAC), et le chlorure de methacrylamidopropyltrimethylammonium (MAPTAC),The branched (co) polyacrylamide is a cationic copolymer of acrylamide and an unsaturated cationic ethylenic monomer selected from the group comprising dimethylaminoethyl acrylate (ADAME), dimethylaminoethyl methacrylate (MADAME), quaternized or salified by different quaternizing acids and agents, benzyl chloride, methyl chloride, alkyl- or aryl chlorides, dimethyl sulphate, dimethyldiallylammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (APTAC), and methacrylamidopropyltrimethylammonium chloride (MAPTAC),
De manière connue, ce copolymère est ramifié par un agent de ramification constitué par un composé présentant au moins deux groupements réactifs choisis dans le groupe comprenant des doubles liaisons, des liaisons aldéhydes ou des liaisons époxy. Ces composés sont bien connus et sont décrits par exemple dans le document
Comme on le sait, un polymère ramifié, ("branched"), est un polymère qui présente sur la chaîne des branches, des groupements ou des ramifications disposées globalement dans un plan et non pas dans les trois directions, contrairement à un polymère réticulé (« cross-linked »); de tels polymères ramifiés, à haut poids moléculaire, sont bien connus comme agents floculants. Ces polyacrylamides ramifiés se distinguent des polyacrylamides réticulés par le fait que dans ces derniers, les groupements sont disposés tridimensionnellement pour conduire à des produits pratiquement insolubles et de poids moléculaire infini.As is known, a branched polymer is a polymer which has branches, groups or branches on the chain which are generally arranged in a plane and not in the three directions, unlike a crosslinked polymer ( "Cross-linked"); such branched, high molecular weight polymers are well known as flocculants. These branched polyacrylamides are distinguished from the crosslinked polyacrylamides in that in the latter, the groups are arranged three-dimensionally to give substantially insoluble products of infinite molecular weight.
On pourra effectuer la ramification de préférence durant (ou éventuellement après) la polymérisation, par exemple par réaction de deux polymères solubles présentant des contre-ions, ou par réaction sur du formaldéhyde ou un composé de métal polyvalent. Souvent, la ramification s'effectue durant la polymérisation par addition d'un agent ramifiantt, et cette solution sera nettement préférée selon l'invention. Ces procédés de polymérisation avec ramification sont bien connus.The branching may preferably be carried out during (or possibly after) the polymerization, for example by reaction of two soluble polymers having counterions, or by reaction with formaldehyde or a polyvalent metal compound. Often, the branching takes place during the polymerization by addition of a branching agent, and this solution will be clearly preferred according to the invention. These branching polymerization processes are well known.
Les agents de ramification que l'on peut incorporer comprennent des agents de ramification ioniques comme les sels de métal polyvalent, le formaldéhyde, le glyoxal, ou encore, et de préférence, des agents de réticulation covalents qui vont copolymériser avec les monomères, de préférence des monomères à insaturation diéthylénique (comme la famille des esters de diacrylates comme les diacrylates de polyéthylène glycols PEG) ou polyéthylénique, du type que l'on utilise classiquement pour la réticulation des polymères solubles dans l'eau, et notamment le méthylènebisacrylamide (MBA) ou encore un quelconque des autres agents de ramification acryliques connus.Branching agents which can be incorporated include ionic branching agents such as polyvalent metal salts, formaldehyde, glyoxal, or preferably covalent crosslinking agents which will copolymerize with the monomers, preferably diethylenically unsaturated monomers (such as the family of diacrylate esters such as PEG polyethylene glycol diacrylates) or polyethylene, of the type conventionally used for the crosslinking of water-soluble polymers, and in particular methylenebisacrylamide (MBA) or any of the other known acrylic branching agents.
Ces agents sont souvent identiques aux agents de réticulation, mais la réticulation peut être évitée, lorsque l'on souhaite obtenir un polymère ramifié et non pas réticulé, par une optimisation des conditions de polymérisation telles que concentration lors de la polymérisation, type et quantité d'agent de transfert, température, type et quantité d'initiateurs, et analogues.These agents are often identical to the crosslinking agents, but the crosslinking can be avoided, when it is desired to obtain a branched and not crosslinked polymer, by an optimization of the polymerization conditions such as concentration during the polymerization, type and amount of polymerization. transfer agent, temperature, type and amount of initiators, and the like.
En pratique, l'agent de ramification est le méthylène bis acrylamide (MBA), introduit a raison de cinq à deux cents (5 a 200) moles par million de moles de monomères, de préférence 5 à 50.In practice, the branching agent is methylenebisacrylamide (MBA), introduced at a rate of five to two hundred (5 to 200) moles per million moles of monomers, preferably 5 to 50 moles.
Avantageusement, la quantité de polyacrylamide ramifié introduite dans la suspension à floculer est comprise entre trente et mille grammes de polymère actif / tonne de pâte sèche (30 et 1000 g / t), soit entre 0,03 pour mille et un pour mille, de préférence de 150 à 500 g / t ; on a observé que si la quantité est inférieure à 0,03 %o (0,03 pour mille), on n'obtient aucune rétention significative; de même, si cette quantité excède 1 %o (1 pour mille), on n'observe aucune amélioration proportionnelle; toutefois, contrairement aux polyacrylamides cationiques linéaires, tels que décrits dans les documents
Comme déjà dit, il importe que le polymère ramifié soit préparé sous forme d'émulsion inverse (eau-dans-huile) pour réaliser le perfectionnement de l'invention. De telles émulsions et leur procédé de préparation sont bien connues de l'homme de métier.As already stated, it is important that the branched polymer be prepared as an inverse emulsion (water-in-oil) to achieve the improvement of the invention. Such emulsions and their method of preparation are well known to those skilled in the art.
Cette approche était condamnée dans le
Il n'était donc pas évident de considérer a fortiori les émulsions inverses eau dans huile dont la teneur en huile est évidemment élevée.It was therefore not obvious to consider a fortiori the inverse emulsions water in oil whose oil content is obviously high.
L'invention était d'autant plus difficile à réaliser qu'il est important de rester dans le domaine des polymères ramifiés et de ne pas passer dans le domaine des polymères réticulés. Or, on sait que techniquement, surtout à l'échelle de production industrielle, la frontière entre les deux zones est très facilement franchie, de manière d'ailleurs irréversible. Comme la zone de ramification est très étroite, on mesure la difficulté de mise au point de l'invention, et c'est le mérite du Demandeur que de s'être attaqué à l'emploi de cette technologie dans le domaine de la fabrication du papier, qui pose des problèmes particuliers et présente des exigences de qualité très sévères.The invention was all the more difficult to realize that it is important to remain in the field of branched polymers and not to go into the field of crosslinked polymers. However, we know that technically, especially at the scale of industrial production, the border between the two zones is very easily crossed, in fact irreversibly. As the branching zone is very narrow, the difficulty of developing the invention is measured, and it is the Claimant's merit that it has tackled the use of this technology in the field of manufacturing the paper, which poses particular problems and presents very stringent quality requirements.
Le risque d'échec était d'autant plus important, ce qui explique peut être le fait que cette technologie n'ait pas été employée, que les émulsions réticulées ne sont pas connues pour procurer un avantage particulier dans le papier.The risk of failure was all the more important, which may explain the fact that this technology has not been used, that cross-linked emulsions are not known to provide a particular advantage in paper.
Par rapport aux polymères linéaires, les polymères ramifiés en poudre du EP précité 0 574 335 avaient déjà apporté un progrès important en ce qui concerne les propriétés et le process de fabrication du papier. L'amélioration était de l'ordre de 20 à 40 % selon les propriétés.Compared with linear polymers, the branched powdered polymers of the
Avec les présentes émulsions ramifiées, on atteint une amélioration de l'ordre de 50 à 60 %, ce qui n'était pas prévisible puisque l'on savait, d'autre part, que les produits réticulés ne fonctionnaient pas.With the present branched emulsions, an improvement of the order of 50 to 60% is reached, which was not foreseeable since it was known, on the other hand, that the crosslinked products did not work.
On comparera à ce sujet les essais 11 (R52) - selon l'invention et 13 (FO 4198) - selon le brevet
Selon l'invention, on utilisera de manière préférée, mais non limitative, un polymère « moyennement ramifié », par exemple à 10 ppm de ramifiant par rapport à la matière active.According to the invention, a "moderately branched" polymer, for example 10 ppm branching with respect to the active material, will be used in a preferred manner, but not limited to.
Comme déjà indiqué plus haut, on pourra utiliser le polymère soit sous la forme de son émulsion inverse de synthèse, dissoute ou « inversée » dans l'eau, soit sous la forme de la solution dans l'eau de la poudre obtenue par séchage de ladite émulsion de synthèse, notamment par séchage par pulvérisation. Le séchage par pulvérisation est un procédé également connu de l'homme de métier. On se référera aux essais ci-dessous pour vérifier que les résultats sont comparables.As already indicated above, it is possible to use the polymer either in the form of its synthetic inverse emulsion, dissolved or "inverted" in water, or in the form of the solution in the water of the powder obtained by drying the said synthetic emulsion, in particular by spray drying. Spray drying is a method also known to those skilled in the art. Refer to the tests below to verify that the results are comparable.
La bentonite, dénommée également "argile smectique gonflante", de la famille des montmorillonites, est bien connue et il n'y a pas lieu de la décrire ici en détail ; ces composés, formés de microcristallites, comportent en surface des sites présentant une forte capacité d'échange cationique susceptible de retenir l'eau (voir par exemple document
On utilise de préférence une bentonite semi-sodique, que l'on introduit juste en amont de la caisse de tête, à raison de 0,1 à 0,5 pour cent (0,1 à 0,5%) du poids sec de la suspension fibreuse.A semi-sodium bentonite, which is introduced just upstream of the headbox, is preferably used at a rate of 0.1 to 0.5 percent (0.1 to 0.5%) of the dry weight of the fibrous suspension.
Comme charge (« filler »), on pourra utiliser les kaolins, le « GCC » ou CaCO3 broyé, le CaCO3 précipité ou « PCC », et analogues.As filler, use may be kaolins, ground "GCC" or CaCO3, precipitated CaCO3 or "PCC", and the like.
L'injection ou introduction du polymère ramifié en émulsion inverse est effectuée avant une étape de cisaillement dans la pâte à papier (ou masse fibreuse à flocculer) plus ou moins diluée selon la pratique de l'homme du métier, et généralement dans la pâte à papier diluée ou « thin stock », cad une pâte diluée à environ 0,7 - 1,5% de matières solides telles que fibres de cellulose, charges éventuelles, et les divers additifs usuels de la fabrication du papier.Injection or introduction of the branched polymer in inverse emulsion is carried out before a shearing step in the paper pulp (or fibrous mass to be flocculated) more or less diluted according to the practice of the person skilled in the art, and generally in the pulp. thin paper, ie a pulp diluted to about 0.7 - 1.5% solids such as cellulose fibers, optional fillers, and the various conventional papermaking additives.
Selon une variante de l'invention, à introduction fractionnée, on introduira une partie du polymère ramifié en émulsion, selon l'invention, au niveau de l'étape de préparation de la pâte épaisse ou « thick stock » à env. 5 % ou plus de matières solides, ou même au niveau de la préparation de la pâte épaisse avant une étape de cisaillement.According to a variant of the invention, fractionally introduced, will be introduced a portion of the emulsion branched polymer, according to the invention, at the stage of preparation of the thick paste or "thick stock" to approx. 5% or more solids, or even in the preparation of the thick slurry before a shear step.
Les exemples suivants illustrent l'invention sans toutefois en limiter la portée.The following examples illustrate the invention without, however, limiting its scope.
Dans un réacteur A, on mélange à température ambiante les constituants de la phase organique de l'émulsion à synthétiser.
- a) - Phase organique
- 252 g d'Exxsol D100
- 18
g de Span 80 - 4 g d'Hypermer 2296
- b) - Dans un bêcher B, on prépare la phase aqueuse de l'émulsion à réaliser en mélangeant :
- 385 g d'acrylamide à 50 %
- 73 g de chlorure d'acrylate éthyl triméthyl
ammonium 80 % - 268 g d'eau
- 0,5 g de méthylène bis acrylamide à 0,25 %
- 0,75 ml du bromate de sodium à 50 g l-1
- 20 ppm d'hypophosphite de sodium par rapport à la matière active
- 0,29 ml de Versenex à 200 g l-1
La réaction terminée, on effectue un « burn out » (traitement au métabisulfite) afin de diminuer la teneur en monomère libre.
L'émulsion est alors incorporée avec son tensio-actif inverse afin de libérer par la suite le polymère en phase aqueuse. Il sera nécessaire d'introduire de 2 à 2,4 % d'alcool éthoxylé. La viscosité Brookfield standard dudit polymère sera de 4,36 cps (viscosité prise à 0,1 % dans une solution 1 M NaCl à 25°C à soixante tours par minute)In a reactor A, the constituents of the organic phase of the emulsion to be synthesized are mixed at ambient temperature.
- a) - Organic phase
- 252 g of Exxsol D100
- 18 g of
Span 80 - 4 g of Hypermer 2296
- b) - In a beaker B, the aqueous phase of the emulsion to be prepared is prepared by mixing:
- 385 g of 50% acrylamide
- 73 g of acrylate ethyl trimethyl
ammonium chloride 80% - 268 g of water
- 0.5 g of 0.25% methylenebisacrylamide
- 0.75 ml of sodium bromate at 50 gl -1
- 20 ppm sodium hypophosphite relative to the active ingredient
- 0.29 ml of Versenex at 200 gl -1
When the reaction is complete, a "burn out" (metabisulphite treatment) is performed in order to reduce the content of free monomer.
The emulsion is then incorporated with its inverse surfactant in order subsequently to release the polymer in the aqueous phase. It will be necessary to introduce 2 to 2.4% ethoxylated alcohol. The standard Brookfield viscosity of said polymer will be 4.36 cps (viscosity taken at 0.1% in a 1 M NaCl solution at 25 ° C. at sixty revolutions per minute).
Selon une variation de la teneur en MBA de 5 à 20 ppm, les résultats en viscosité UL sont les suivants :According to a variation of the MBA content of 5 to 20 ppm, the UL viscosity results are as follows:
(*) : hypophosphite de sodium, agent de transfert.
(1) : regain ionique en %.
(2) : regain de viscosité intrinsèque en %.
EM140CT : émulsion standard de très haut poids moléculaire ne contenant aucun agent ramifiant. EM140L : émulsion standard de haut poids moléculaire ne contenant aucun agent ramifiant.
EM140LH : émulsion de poids moléculaire moyen ne contenant aucun agent ramifiant.
EM140BD : émulsion réticulée ne contenant aucun agent de transfert et 5 ppm d'agent réticulant.
SD 102 : émulsion R 102 séchée par pulvérisation, et poudre obtenue dissoute dans l'eau à 5 g de polymère actif / litre.FO 4198: branched powder containing 20 ppm transfer agent and 5 ppm branching agent (according to
(*): sodium hypophosphite, transfer agent.
(1): ionic increase in%.
(2): intrinsic viscosity increase in%.
EM140CT: standard emulsion of very high molecular weight containing no branching agent. EM140L: standard high molecular weight emulsion containing no branching agent.
EM140LH: Medium molecular weight emulsion containing no branching agent.
EM140BD: crosslinked emulsion containing no transfer agent and 5 ppm crosslinking agent.
SD 102: spray-dried emulsion R 102, and powder obtained dissolved in water at 5 g of active polymer / liter.
On note que les produits linéaires ne développent pas de regain ioniqueRI et voient leur viscosité intrinsèque IV diminuer sous l'effet d'un fort cisaillement (deux des valeurs de IV sont négatives); les produits ramifiés en émulsion développent du regain ionique RI, mais pas de IV ( valeurs < = 0); les produits réticulés développent un fort regain ionique et un très fort regain de IV.It is noted that the linear products do not develop an ionic surgeI and their intrinsic viscosity IV decrease under the effect of a high shear (two of the values of IV are negative); branched emulsion products develop ionic RI but not IV (values <= 0); cross-linked products develop a strong ionic surge and a very strong IV boost.
- avec X :with X:
- ionicité après cisaillement en meq/g.ionicity after shearing in meq / g.
- Y :Y:
- ionicité avant cisaillement en meq/g.ionicity before shearing in meq / g.
- avec V1 :with V1:
- viscosité intrinsèque après cisaillement en dl/gintrinsic viscosity after shear in dl / g
- V2 :V2:
- viscosité intrinsèque avant cisaillement en dl/gintrinsic viscosity before shear in dl / g
Une partie des émulsions citées ci-dessus feront l'objet d'une étude d'efficacité en rétention égouttage sur une « formette automatique de rétention » du Centre Technique du Papier.Some of the emulsions mentioned above will be the subject of an efficiency study in draining retention on an "automatic retention form" of the Center Technique du Papier.
20 % de carbonate de calcium naturel.20% of mechanical pulp
20% natural calcium carbonate.
Collage en milieu neutre avec 2 % d'une émulsion d'alkyle cétène dimère.Bonding in a neutral medium with 2% of a ketene dimeric emulsion.
La pâte utilisée est diluée à une consistance de 1,5 %. On prélève 2,24 g sec de pâte, soit 149 g de pâte à150% puis l'on dilue à 0,4 % avec des eaux claires.The paste used is diluted to a consistency of 1.5%. 2.24 g of pulp are taken, ie 149 g of pulp at 150% and then diluted to 0.4% with clear water.
Le volume de 560 ml est introduit dans le cylindre en plexiglas de la formette automatisée et l'on démarre la séquence.
- t = 0 s, démarrage agitation à 1500 rpm.
- t = 10 s, addition du polymère.
- t = 60 s, réduction automatique à 1000 rpm et addition si nécessaire de la bentonite.
- t = 75 s, arrêt de l'agitation, formation de la feuille avec le vide sous toile puis récupération des eaux blanches.
- t = 0 s, starting agitation at 1500 rpm.
- t = 10 s, addition of the polymer.
- t = 60 s, automatic reduction to 1000 rpm and addition of bentonite if necessary.
- t = 75 s, stopping the agitation, forming the sheet with the vacuum under canvas then recovery of white water.
On effectue alors les opérations suivantes :
- mesure de la turbidité des eaux sans toile.
- dilution d'un bêcher de pâte épaisse pour une nouvelle feuille avec les eaux sous toiles recueillies.
- séchage de la feuille dite 1 ère passe.
- démarrage d'une nouvelle séquence afin de réaliser la feuille dite 2nde passe.
- measurement of the turbidity of water without canvas.
- dilution of a beaker of thick paste for a new leaf with the collected underwater.
- drying of the so-called first pass sheet.
- starting a new sequence in order to make the sheet known as the 2nd pass.
Après 3 passes, l'on change de produits à tester.After 3 passes, we change products to test.
Les analyses suivantes sont alors réalisées :
- mesure des matières en suspension des eaux sous toile (Norme TAPPI : T 656 cm / 83 )
- mesure des cendres des feuilles, (Norme TAPPI : T 211 om - 93 )
- mesure de la turbidité 30' après que les fibres soient déposées afin de connaître l'état du milieu ionique.
- mesure du degré d'égouttabilité de la pâte avec un Canadian Standard Freeness (CSF; Norme TAPPI T 227 om - 94).
- measurement of suspended solids under canvas (TAPPI standard: T 656 cm / 83)
- measurement of leaf ash, (TAPPI standard: T 211 om - 93)
- measuring the turbidity 30 'after the fibers are deposited in order to know the state of the ionic medium.
- measuring the degree of drainability of the pulp with a Canadian Standard Freeness (CSF TAPPI Standard T 227 om - 94).
Notes pour les Tableaux ( I ) et ( II ) ci-après:Notes for Tables (I) and (II) below:
- X =X =
- mesure dite à la première passe.measure said to the first pass.
- R1 =R1 =
- mesure dite à la seconde passe (1 er recyclage)measured in the second pass (1st recycling)
- R2 =R2 =
- mesure dite à la troisième passe (2ème recyclage)measure said to the third pass (2nd recycling)
Les polymères réticulés 1, 4, 9, 12 ne présentent pas d'intérêt quant à la floculation et la rétention des fines et des charges malgré le fort taux de cisaillement appliqué en cours de process sur la masse fibreuse (et non pas appliqué sur le polymère lui-même), ici 1500 tr/min., qui est caractéristique de ce type de système de rétention microparticulaire. Ils montrent une faible capture des charges et matières colloidales car aucune réduction de turbidité n'est observée.The
La combinaison avec la bentonite n'améliore pas de manière significative l'efficacité en rétention et améliore seulement légèrement l'efficacité en égouttage.The combination with bentonite does not significantly improve retention efficiency and only slightly improves drainage efficiency.
Pour le polymère linéaire, son comportement suit la tendance, amélioration des rétentions de charges et de fines.For the linear polymer, its behavior follows the trend, improving the retention of charges and fines.
La combinaison selon l'invention d'un polymère ramifié en émulsion inverse et de bentonite apporte un gain net en rétention de charge et en rétention totale, et se révèle être supérieure au système connu polymère linéaire / bentonite.The combination according to the invention of a branched polymer in inverse emulsion and bentonite provides a net gain in charge retention and total retention, and is found to be superior to the known linear polymer / bentonite system.
Le pouvoir de coagulation est supérieur pour un polymère ramifié en émulsion, ce qui se traduit par une excellente réduction de la turbidité à 30' (30 min.).The coagulation power is higher for a branched polymer in emulsion, which results in an excellent reduction of the turbidity at 30 '(30 min.).
L'essai R 52 et l'essai R 102 montrent que l'invention permet d'obtenir des produits ramifiés présentant des viscosités UL plus élevées que celles accessibles par une polymérisation en gel telle que décrite dans le
L'essai SD 102 montre que le polymère utilisé sous la forme d'une solution dans l'eau de la poudre obtenue par séchage de l'émulsion inverse de la synthèse du polymère se comporte comme le polymère utilisé sous la forme de la solution dans l'eau de ladite émulsion inverse de synthèse. Notamment, on n'observe pas de dégradation du polymère durant l'étape de séchage par pulvérisation.Test SD 102 shows that the polymer used in the form of a solution in the water of the powder obtained by drying the inverse emulsion of the synthesis of the polymer behaves as the polymer used in the form of the solution in the water of said synthesis inverse emulsion. In particular, there is no degradation of the polymer during the spray drying step.
L'essai R 52 peut être utilement comparé à l'essai FO 4198 (poudre) car les polymères présentent la même chimie, donc la même cationicité, et le même % de MBA, tandis que le R 52 utilisé selon l'invention est très supérieur à la poudre en termes d'égouttage et de rétention (96,3 à rapprocher de 83,6); on comparera également la turbidité NTU après 30 min. , de 32 par rapport à 75 unités NTU.The test R 52 can be usefully compared to the test FO 4198 (powder) because the polymers have the same chemistry, therefore the same cationicity, and the same% MBA, while the R 52 used according to the invention is very higher than the powder in terms of dripping and retention (96.3 to be closer to 83.6); the NTU turbidity will also be compared after 30 minutes. , of 32 compared to 75 NTU units.
De telles valeurs de viscosité UL conduisent notamment à un égouttage très amélioré.Such values of UL viscosity lead in particular to a very improved drainage.
L'invention concerne donc un procédé de fabrication d'une feuille de papier ou carton ou analogue, utilisant un agent de rétention, qui consiste en un (co)polymère acrylique tel que décrit ci-dessus, ramifié, en émulsion inverse, et qui est caractérisé en ce que sa viscosité UL est > 3, ou > 3,5 ou > 4. Ledit agent peut être utilisé soit en émulsion inversée à l'eau, soit en solution de la poudre obtenue par séchage de l'émulsion, comme décrit ci-dessus.The invention therefore relates to a method for producing a sheet of paper or cardboard or the like, using a retention agent, which consists of an acrylic (co) polymer as described above, branched, in inverse emulsion, and which is characterized in that its UL viscosity is> 3, or> 3.5 or> 4. Said agent can be used either in inverted emulsion with water, or in solution of the powder obtained by drying the emulsion, as described above.
Dans un réacteur A, on mélange à température ambiante les constituants de la phase organique de l'émulsion à synthétiser.
- a) - Phase organique :
- 252 g d'exxsol D100
- 18
g de Span 80 - 4 g d'Hypermer 2296.
- b) - Dans un bécher B, on prépare la phase de l'émulsion à réaliser en mélangeant
- 378 g d'acrylamide à 50 %
- 102,2 g de chlorure d'acrylamido-propyl triméthyl ammonium (60 %)
- 245,7 g d'eau
- 0,5 g de méthylène bis acrylamide à 0,25 %
- 0,75 ml de bromate de sodium à 50 g/l
- 20 ppm d'hypophosphite de sodium par rapport à la matière active
- 0,29 ml de Versenex à 200 g/l
- a) - Organic phase:
- 252 g of exxsol D100
- 18 g of
Span 80 - 4 g of Hypermer 2296.
- b) - In a beaker B, the phase of the emulsion to be prepared is prepared by mixing
- 378 g of 50% acrylamide
- 102.2 g of acrylamido-propyltrimethylammonium chloride (60%)
- 245.7 g of water
- 0.5 g of 0.25% methylenebisacrylamide
- 0.75 ml of sodium bromate at 50 g / l
- 20 ppm sodium hypophosphite relative to the active ingredient
- 0.29 ml of Versenex at 200 g / l
On mélange le contenu de B dans A sous agitation. Après le mélange des phases, on cisaille l'émulsion au mixer pendant 1 minute afin de créer l'émulsion inverse. L'émulsion est alors dégazée par un bullage d'azote puis après 20 minutes, l'addition progressive du métabisulfite entraîne l'initiation puis la polymérisation.The contents of B are mixed in A with stirring. After mixing the phases, the emulsion is sheared for 1 minute in order to create the inverse emulsion. The emulsion is then degassed by bubbling nitrogen and after 20 minutes, the gradual addition of metabisulfite leads to initiation and then polymerization.
La réaction terminée, on effectue un « burn out » afin de diminuer la teneur en monomère libre.When the reaction is complete, a "burn out" is performed in order to reduce the content of free monomer.
L'émulsion est alors incorporée avec son tensio-actif inverseur afin de libérer par la suite le polymère en phase aqueuse.The emulsion is then incorporated with its reversing surfactant in order subsequently to release the polymer in the aqueous phase.
Les résultats appellent les mêmes commentaires que ceux de l'exemple 1 et confirment le grand intérêt de la présente invention.The results call for the same comments as those of Example 1 and confirm the great interest of the present invention.
L'invention concerne un procédé pour la fabrication d'une feuille de papier ou carton ou analogue mettant en oeuvre des agents de rétention décrits ci-dessus, caractérisés en ce qu'ils consistent en, ou comprennent, au moins un (co)polymère du type décrit, ramifié, préparé en émulsion inverse, destiné à coopérer avec un agent secondaire de rétention après une étape intermédiaire de cisaillement de la pâte à papier, ainsi que les procédés de fabrication de feuilles de papier, carton ou analogue, utilisant les agents décrits ci dessus dans le procédé selon l'invention, et les feuilles de papier, carton et analogues ainsi obtenues.The invention relates to a method for producing a sheet of paper or cardboard or the like employing retention agents described above, characterized in that they consist of, or comprise, at least one (co) polymer of the type described, branched, prepared in inverse emulsion, intended to cooperate with a secondary retention agent after an intermediate step of shearing the paper pulp, as well as processes for producing sheets of paper, cardboard or the like, using the agents described above in the process according to the invention, and the sheets of paper, cardboard and the like thus obtained.
Ledit agent peut être utilisé soit en émulsion inversée à l'eau, soit en solution de la poudre obtenue par séchage de l'émulsion, comme décrit ci-dessus.
(X) = réticulé ; (Y) ramifié; (/) = linéaire
(X) = réticulé ; (Y) = ramifié ; (/) = linéaire
(X) = crosslinked; (Y) branched; (/) = linear
(X) = crosslinked; (Y) = branched; (/) = linear
Claims (12)
- Process for manufacturing a sheet of paper or cardboard or the like having improved retention and dewatering characteristics, of the type using a dual system of branched acrylic polymer and bentonite or a kaolin optionally treated as primary retention agent an as secondary retention agent, the introductions of which are separated by a shearing stage of the fibrous suspension or mass or wood pulp, characterised in that said polymer is a branched acrylic (co)polymer prepared in the form of an invert water-in-oil emulsion which is a cationic copolymer of acrylamide and of an unsaturated cationic ethylenic monomer, selected from the group comprising dimethylaminoethyl acrylate (ADAME), dimethylaminoethyl methacrylate (MADAME), which are quaternised or salified by various acids and quaternising agents, benzyl chloride, methyl chloride, alkyl or aryl chlorides, dimethyl sulphate, dimethyldiallylammonium chloride (DADMAC), acrylamidopropyl- trimethylammonium chloride (APTAC) and methacrylamidopropyl-trimethylammonium chloride (MAPTAC), used either as an emulsion inverted with water or as a solution of the powder obtained by drying the emulsion, and in that its viscosity (UL) is > 3, preferably > 3.5 and preferably > 4.
- Process according to claim 1, characterised in that the branched acrylic (co)polymer prepared as an invert emulsion is introduced into the wood pulp in a concentration from 0.03 to one per thousand (0.03 to 1%o) by weight, that is from 30 to 1000 g/t, of the dry weight of the fibrous wood pulp suspension, preferably from 0.15 to 0.5 per thousand (0.15 to 0.5%o), that is from 150 to 500 g/t.
- Process according to any one of claims 1 to 2, characterised in that the branched acrylic (co)polymer as an invert emulsion is branched by a branching agent formed by a polyfunctional compound containing at least two reactive groups selected from the group comprising double bonds, aldehyde bonds or epoxy bonds.
- Process according to any of claims 1 to 3, characterised in that the branched acrylic (co)polymer as an invert emulsion is branched by a branching agent formed by methylenebisacrylamide (MBA).
- Process according to claim 4, characterised in that the MBA is introduced in a concentration of 5 to 200 moles per million moles of monomers.
- Process according to claim 4 or 5, characterised in that the bentonite is a semi-sodium bentonite used in a proportion of 0.1 to 0.5 per cent (0.1 to 0.5%) of the dry weight of the fibrous suspension.
- Process according to claim 4, 5 or 6, characterised in that the filler-containing pulp used is diluted, then the polymer is added as main retention agent, a shearing stage is carried out, for example in the mixing pump or fan pump, then the bentonite is added as secondary retention agent.
- Process according to claim 7, characterised in that the amount of branched polyacrylamide (or more generally of branched acrylic (co)polymer) introduced either as an invert water-in-oil emulsion inverted with water, or as a solution of the powder obtained by drying the emulsion, is between 0.03 and 1‰, that is between thirty and a thousand grammes/tonne (30 and 1000 g/ t) of dry pulp.
- Process according to claim 7 or 8, characterised in that the amount of branched polyacrylamide (or more generally of branched acrylic (co)polymer) introduced either as an invert water-in-oil emulsion inverted with water, or as a solution of the powder obtained by drying the emulsion, is between 0.15 and 0.5%o (that is between 150 and 500 g/t).
- Process according to claim 7, 8 or 9, characterised in that the bentonite is replaced by kaolin, optionally pretreated with a polyelectrolyte, as secondary retention agent.
- Process according to any of claims 1 to 10, characterised in that the branched polymer prepared as an invert emulsion is injected or introduced (either as an emulsion inverted with water or as a solution of the powder obtained by drying the emulsion) prior to a shearing stage into the more or less dilute wood pulp (or fibrous mass to be flocculated) according to the practice of the person skilled in the art, and generally into the dilute wood pulp or thin stock, in other words a pulp diluted to approximately 0.7 to 1.5% of solid matter, such as cellulose fibres, optional fillers, and the various additives conventional in paper manufacture.
- Process according to any of claims 1 to 10, characterised in that a portion of the branched polymer is introduced as an emulsion during the stage of preparation of the thick pulp or thick stock containing approximately 5% or more of solid matter, or even during the preparation of the thick pulp prior to a shearing stage.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR9807144 | 1998-06-04 | ||
FR9807144A FR2779452B1 (en) | 1998-06-04 | 1998-06-04 | PROCESS FOR PRODUCING PAPER AND CARDBOARD AND NOVEL RETENTION AND DRIPPING AGENTS THEREOF, AND PAPER AND CARDBOARD THUS OBTAINED |
PCT/FR1999/001278 WO1999063159A1 (en) | 1998-06-04 | 1999-06-01 | Method for making paper and cardboard and retention and dewatering agents |
Publications (4)
Publication Number | Publication Date |
---|---|
EP1092064A1 EP1092064A1 (en) | 2001-04-18 |
EP1092064B1 EP1092064B1 (en) | 2003-11-19 |
EP1092064B2 EP1092064B2 (en) | 2009-04-22 |
EP1092064B9 true EP1092064B9 (en) | 2009-10-21 |
Family
ID=9527102
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP99923647A Expired - Lifetime EP1092064B9 (en) | 1998-06-04 | 1999-06-01 | Method for making paper and cardboard |
Country Status (9)
Country | Link |
---|---|
EP (1) | EP1092064B9 (en) |
JP (1) | JP4699608B2 (en) |
KR (1) | KR100685533B1 (en) |
AT (1) | ATE254693T1 (en) |
AU (1) | AU4043999A (en) |
CA (1) | CA2334196C (en) |
DE (1) | DE69912954T3 (en) |
FR (1) | FR2779452B1 (en) |
WO (1) | WO1999063159A1 (en) |
Families Citing this family (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2779752B1 (en) * | 1998-06-12 | 2000-08-11 | Snf Sa | PROCESS FOR PRODUCING PAPER AND CARDBOARD AND NOVEL RETENTION AGENTS THEREOF, AND PAPER AND CARDBOARD THUS OBTAINED |
DE20220979U1 (en) | 2002-08-07 | 2004-10-14 | Basf Ag | Preparation of paper, pasteboard, or cardboard involving cutting of the paper pulp, addition of microparticles of cationic polymer, e.g. cationic polyamide, and a finely divided inorganic component after the last cutting step |
MXPA04003942A (en) * | 2003-05-05 | 2007-06-29 | German Vergara Lopez | Retention and drainage system for the manufacturing of paper, paperboard and similar cellulosic products. |
FR2869626A3 (en) * | 2004-04-29 | 2005-11-04 | Snf Sas Soc Par Actions Simpli | METHOD FOR MANUFACTURING PAPER AND CARDBOARD, NEW CORRESPONDING RETENTION AND DRAINING AGENTS, AND PAPERS AND CARTONS THUS OBTAINED |
DE102004044379B4 (en) | 2004-09-10 | 2008-01-10 | Basf Ag | Process for the production of paper, paperboard and cardboard and use of a retention agent combination |
DE102004063005A1 (en) | 2004-12-22 | 2006-07-13 | Basf Ag | Process for the production of paper, cardboard and cardboard |
DE102008000811A1 (en) | 2007-03-29 | 2008-10-09 | Basf Se | Preparing paper, paperboard and cardboard, comprises shearing the paper material, adding ultrasound treated microparticle system and fine-particle inorganic component to the paper material and dewatering the paper material to form sheets |
CA2735371C (en) | 2008-09-02 | 2013-10-15 | Basf Se | Method for manufacturing paper, board and cardboard using endo-beta-1,4-glucanases as drainage aids |
CA2936031C (en) | 2009-09-15 | 2019-09-03 | Adrian Peter Revington | Techniques for flocculating and dewatering fine tailings |
EP2477707B8 (en) | 2009-09-15 | 2017-07-26 | Suncor Energy Inc. | Process for drying fine tailings |
WO2011050440A1 (en) | 2009-10-30 | 2011-05-05 | Suncor Energy Inc. | Depositing and farming methods for drying oil sand mature fine tailings |
US9404223B2 (en) * | 2012-02-01 | 2016-08-02 | Basf Se | Process for the manufacture of paper and paperboard |
GB2567456B (en) | 2017-10-12 | 2021-08-11 | Si Group Switzerland Chaa Gmbh | Antidegradant blend |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4617362A (en) * | 1984-12-31 | 1986-10-14 | Allied Corporation | Inverse emulsion polymers with improved incorporation of diallyldimethylammonium chloride |
EP0202780B2 (en) † | 1985-04-25 | 1998-12-09 | Ciba Specialty Chemicals Water Treatments Limited | Flocculation processes |
FR2589145A1 (en) * | 1985-10-25 | 1987-04-30 | Snf Sa | Flocculating agent for the treatment of sludges based on branched water-soluble addition polymers |
GB8602121D0 (en) † | 1986-01-29 | 1986-03-05 | Allied Colloids Ltd | Paper & paper board |
ATE118224T1 (en) * | 1988-12-19 | 1995-02-15 | Cytec Tech Corp | HIGH PERFORMANCE POLYMER FLOCCULATING AGENT. |
US5354481A (en) † | 1988-12-19 | 1994-10-11 | Cytec Technology Corp. | Water-soluble highly branched polymeric microparticles |
US5405554A (en) † | 1990-02-08 | 1995-04-11 | Cytec Technology Corp. | High performance dewatering aids |
US5234548A (en) * | 1992-01-02 | 1993-08-10 | Vinings Industries Inc. | Production of paper and paperboard |
FR2692292B1 (en) * | 1992-06-11 | 1994-12-02 | Snf Sa | Method for manufacturing paper or cardboard with improved retention. |
GB9313956D0 (en) * | 1993-07-06 | 1993-08-18 | Allied Colloids Ltd | Production of paper |
GB9410920D0 (en) † | 1994-06-01 | 1994-07-20 | Allied Colloids Ltd | Manufacture of paper |
FR2740482B1 (en) * | 1995-10-30 | 1997-11-21 | Snf Sa | PROCESS FOR IMPROVING RETENTION IN A PAPER, CARDBOARD AND THE LIKE PROCESS |
SE9504081D0 (en) * | 1995-11-15 | 1995-11-15 | Eka Nobel Ab | A process for the production of paper |
JP3614609B2 (en) * | 1996-09-10 | 2005-01-26 | ハイモ株式会社 | Papermaking chemicals, papermaking methods and methods for producing papermaking chemicals |
-
1998
- 1998-06-04 FR FR9807144A patent/FR2779452B1/en not_active Expired - Lifetime
-
1999
- 1999-06-01 KR KR1020007013706A patent/KR100685533B1/en not_active IP Right Cessation
- 1999-06-01 JP JP2000552347A patent/JP4699608B2/en not_active Expired - Lifetime
- 1999-06-01 WO PCT/FR1999/001278 patent/WO1999063159A1/en active IP Right Grant
- 1999-06-01 EP EP99923647A patent/EP1092064B9/en not_active Expired - Lifetime
- 1999-06-01 DE DE69912954T patent/DE69912954T3/en not_active Expired - Lifetime
- 1999-06-01 AT AT99923647T patent/ATE254693T1/en active
- 1999-06-01 CA CA002334196A patent/CA2334196C/en not_active Expired - Lifetime
- 1999-06-01 AU AU40439/99A patent/AU4043999A/en not_active Abandoned
Also Published As
Publication number | Publication date |
---|---|
WO1999063159A1 (en) | 1999-12-09 |
EP1092064A1 (en) | 2001-04-18 |
EP1092064B2 (en) | 2009-04-22 |
JP4699608B2 (en) | 2011-06-15 |
KR100685533B1 (en) | 2007-02-22 |
DE69912954D1 (en) | 2003-12-24 |
KR20010052553A (en) | 2001-06-25 |
AU4043999A (en) | 1999-12-20 |
JP2002517626A (en) | 2002-06-18 |
CA2334196A1 (en) | 1999-12-09 |
EP1092064B1 (en) | 2003-11-19 |
DE69912954T3 (en) | 2010-01-28 |
ATE254693T1 (en) | 2003-12-15 |
CA2334196C (en) | 2008-07-15 |
FR2779452B1 (en) | 2000-08-11 |
FR2779452A1 (en) | 1999-12-10 |
DE69912954T2 (en) | 2004-11-11 |
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