Method for paper production

FIELD: pulp-and-paper industry, in particular paper or board production.

SUBSTANCE: claimed method includes providing of slurry containing cellulose fiber and at least sizing agent interacting with cellulose. Sizing agent is selected from group containing ketene dimmers and acid anhydrides. Cationic vinyl polymer obtained by additional polymerization, containing aromatic units and anionic vinyl polymer obtained by additional polymerization and having molecular mass from 6000-100000 are introduced into slurry. Then obtained slurry is dehydrated and paper leaf is formed.

EFFECT: increased effectiveness of sizing, dehydration and retention.

11 cl, 3 tbl, 2 ex

 

The present invention relates to a method for producing paper or paperboard, including the introduction of two different polymers in aqueous cellulosic suspension, and one is a cationic vinyl polymer obtained additive polymerization containing aromatic units, and the other anionic polymer having srednevekovoy molecular weight in the range of from about 6,000 to about 100,000 selected from the group consisting of vinyl polymers, additive obtained by polymerization, and condensation polymers.

Background of invention

Internal sizing agent is usually injected at the end of the wet method of producing the paper, causing the paper ability to adsorb the liquid is reduced. Commonly used sizing agents are sizing agent on the basis of derivatives of rosin and a sizing agent that interacts with cellulose, especially dimers of Ketanov and anhydrides of carboxylic acids. Multipurpose office paper should be pretty much glued to function properly in modern high-speed copiers. One way to get paper that is fully taped, i.e. has a number of Cobb60below 30 or the contact angle of water droplets on the paper where the angles greater than 80 degrees through 10 indicate Ho is Osee sizing, is the introduction of a larger amount of sizing agent in the suspension. However, the probability of the inevitability of problems at a paper mill increases, as well as the cost of production.

In addition to introducing the pulp suspension sizing substances in suspension imposed dewatering and retention agents. As the name indicates, the latter agents improve both the dewatering and retention of the pulp suspension. Unexpectedly, it was found that in accordance with the present invention the efficiency of the sizing is improved by introduction of at least two different types of polymers in the pulp suspension, in which the polymers act as dewatering and retention agents. Thus, the application of this method has a positive effect on the sizing, dewatering and retention. There is also an impact on the suspension having a high conductivity.

The closest analogue of the present invention is U.S. patent 5595629, which describes a method of producing paper with improved retention and dehydration by adding a cationic polymer containing an aromatic group and an anionic polymer, which is a formaldehyde condensate naphtalenesulfonic acid. The reference is not described anionic vinyl additive polymer. In U.S. patent 5595629 not the ferocious also ketene dimers and acid anhydrides, in this patent does not mention the efficiency of the sizing.

According to the present invention is installed, which is especially improved sizing can be obtained by the method of producing paper or paperboard, containing ensuring the suspension containing cellulose and at least a sizing substance, dehydration specified suspension from forming in the sheet of paper, so the suspension is injected cationic vinyl polymer obtained additive polymerization containing aromatic units and anionic polymer having srednevekovoy molecular weight in the range of from about 6,000 to about 100,000 selected from the group consisting of vinyl polymers, additive obtained by polymerization, and condensation polymers.

Detailed description of the invention

The present invention is not limited to specific types of pulp suspensions, but may be applied to the cellulosic suspension containing the original or regenerated cellulose and various fillers such as calcium carbonate. the pH of the suspension may vary from acid, which is present in the case, when using a sizing agent, derived from rosins, to neutral or alkaline. If you are using a sizing agent that interacts with the pulp, the pH of the pulp suspension is one who depart from neutral to alkaline, i.e. in the range of from about 5 to about 10, which also makes possible the inclusion of materials of inorganic fillers in suspension, for example, precipitated calcium carbonate and clay. Two different polymer is conveniently administered in sufficiently dilute suspension containing lignosellus, commonly called the diluted mass, having a concentration of from 0.1 to 3.0 wt.% in relation to the dry fibers.

How, moreover, does not depend on the type of sizing agent, thus any sizing the substance or mixture sizing substances may be present in the pulp suspension. Preferably the pulp suspension contains a sizing agent that interacts with cellulose, typically present in amounts of from 0.01 to 5 wt.% relative to the dry fiber, and has a pH value when sizing a substance that interacts with cellulose, is still functioning properly, i.e. pH in the range from 5 to 10. Suitable sizing agents that interact with cellulose are dimers of Ketanov, multimer of Ketanov, acid anhydrides, organic isocyanates, carbamylcholine and mixtures thereof, where the dimer Ketanov and anhydrides of carboxylic acids are preferred.

According to the present method in the pulp suspension is injected cationic vinyl polymer obtained addition the th polymerization, containing aromatic units and anionic vinyl polymer obtained additive polymerization with srednevekovoy molecular weight in the range of from about 6,000 to about 100,000. Typically, the cationic polymer is introduced into the suspension until the introduction of the anionic polymer. Usually for the introduction of the cationic polymer should stage or phase shift, whereas the anionic polymer is injected after any stage, providing a significant shift, but before the molding of a sheet of paper.

Cationic vinyl polymer obtained additive polymerization containing aromatic units

Cationic vinyl polymer obtained additivepolymerization containing aromatic units can be linear or branched and contains a monomer having anionic or potentially anionic group, if the total charge of the polymer is cationic. However, the cationic polymer is preferably produced by polymerization of the reaction mixture is essentially free from monomers having anionic groups or groups which can become anionic in aqueous compositions. The cationic polymer may be homopolymer or copolymer containing cationic aromatic monomers, cationic non-aromatic monomers and nonionic monomers, the latter are non-aromatic. Suitable cationic vinyl polymer content is t cationic aromatic monomers, selected from the group consisting of acrylamide, (meth)acrylamide, acrylate and (meth)acrylate, therefore, the abovementioned cationic monomers preferably have at least one aromatic group covalently linked to the nitrogen atom either directly or via a hydrocarbon group, which may have heteroatoms. Preferably the cationic vinyl polymer obtained additive polymerization containing aromatic units, contains aromatic (meth)acrylamide and/or (meth)acrylate monomers present in the polymer in an amount of from about 2 mol.% to about 97 mol.%. Cationic vinyl polymer obtained additive polymerization containing aromatic units, are eligible to receive a cationic polymerization of the monomer or the reaction mixture containing Monomeric mixture containing a cationic monomer represented by the General formula (I):

in which R1represents N or CH3; R2and R3represent independently from each other hydrogen or alkyl group having from 1 to 3 carbon atoms, usually 1-2 carbon atoms; A1represents O or NH; B1represents alkylenes group having from 2 to 8 carbon atoms, preferably from 2 to 4 carbon atoms, hydroxypropranolol group or Hydra is citylevel group; Q represents a Deputy containing aromatic group, preferably phenyl group or substituted phenyl group, which may be attached to the nitrogen through alkalinous groups, typically with from 1 to 3 carbon atoms, preferably 1-2 carbon atoms, and preferably Q is a benzyl group (-CH2-C6H5); X-is an anionic counterion, typically a halide like chloride. Examples of suitable monomers represented by the General formula (I)include Quaternary monomers, obtained by processing benzylchloride dialkylaminoalkyl(meth)acrylates, such as dimethylaminoethyl(meth)acrylate, diethylaminoethyl(meth)acrylate and dimethylaminopropyl(meth)acrylate, and dialkylaminoalkyl (meth)acrylamides, such as dimethylaminoethyl(meth)acrylamide, diethylaminoethyl(meth)acrylamide, dimethylaminopropyl(meth)acrylamide and diethylaminopropyl(meth)acrylamide. Preferred cationic monomers of General formula (I) include dimethylaminoethylacrylate Quaternary salt, dimethylaminoethylmethacrylate Quaternary salt and dimethylaminopropyl(meth)acrylamidophenylboronic Quaternary salt.

Cationic vinyl polymer may be homopolymers derived from a cationic monomer having an aromatic group is, or a copolymer obtained from a monomer mixture comprising a cationic monomer having an aromatic group, and one or more copolymerizate monomers. Suitable copolymerizate non-ionic monomers include monomers represented by the General formula (II):

in which R4represents N or CH3; R5and R6each represents a hydrocarbon group, suitably alkyl, having from 1 to 6, suitably from 1 to 4, usually 1 to 2 carbon atoms; And2represents O or NH;2represents alkylenes group with from 2 to 8 carbon atoms, suitably from 2 to 4 carbon atoms, or hydroxypropranolol group or, alternatively, a and b are both zero, so there is a simple relationship between C and N (O=C-NR5R6). Examples of suitable copolymerizate monomers of this type include(meth)acrylamide; acrylamidoethyl monomers like N - alkyl(meth)acrylamides and N,N-dialkyl(meth)acrylamides, for example, N-n-propylacetamide, N-isopropyl(meth)acrylamide, N-n-butyl(meth)acrylamide, N-isobutyl(meth)acrylamide and N-tert-butyl(meth)acrylamide; and dialkylaminoalkyl(meth)acrylamide, such as dimethylaminoethyl(meth)acrylamide, diethylaminoethyl(meth)acrylamide, dimethylaminopropyl(meth)acrylamide and diethylaminopropyl(meth)acrylamide; acilitating is the following monomers, this dialkylaminoalkyl(meth)acrylates, such as dimethylaminoethyl(meth)acrylate, diethylaminoethyl(meth)acrylate, tert-butylaminoethyl(meth)acrylate and dimethylaminoethylmethacrylate; and vinylamide, for example, N-vinylformamide and N-vinylacetate. Preferred copolymerizate nonionic monomers include acrylamide and methacrylamide, i.e. the (meth)acrylamide, and the main polymer is preferably acrylamidoethyl polymer.

Suitable copolymerizate cationic monomers include monomers represented by the General formula (III):

in which R7represents N or CH3; R8and R9represents preferably a hydrocarbon group, suitably, the alkyl group having from 1 to 3 carbon atoms; R10can represent hydrogen or preferably a hydrocarbon group, preferably alkyl group having from 1 to 8 carbon atoms, usually 1-2 carbon atoms; And3represents O or NH;3represents alkylenes group with from 2 to 4 carbon atoms, preferably from 2 to 4 carbon atoms, or hydroxypropranolol group, and X-is an anionic counterion, typically a methyl sulfate or halide such as chloride. Examples of suitable cationic copolymerizate monomial is s include additive salt of the acid and Quaternary ammonium salt dialkylaminoalkyl(meth)acrylate and dialkylaminoalkyl(meth)acrylamides, above, usually derived from acids like HCl, H2SO4etc. or quaternized agents such as methyl chloride, dimethylsulfate etc.; and diallyldimethylammoniumchloride. Preferred copolymerizate cationic monomers include dimethylaminoethyl(meth)greatmajority Quaternary salt, diallyldimethylammoniumchloride and dimethylaminopropyl(meth)acrylamidophenylboronic Quaternary salt. Copolymerizate anionic monomers like acrylic acid, methacrylic acid, taconova acid, different from sulphonated vinyl additive monomers, etc. can be used preferably in small quantities.

Cationic vinyl polymer obtained additivethe polymerization can be obtained from the monomer mixture, usually containing from 1 to 99 mol.%, suitably from 2 to 50 mol.% and preferably from 5 to 20 mol.% cationic monomer having an aromatic group, preferably represented by the General formula (I), and from 99 to 1 mol.%, suitably, from 98 to 50 mole% and preferably from 95 to 65 mol.% other copolymerizate monomers which preferably contain acrylamide or methacrylamide ((meth)acrylamide), and Monomeric mixture suitably contains from 98 to 50 mole% and preferably from 95 to 80 mol.% (meth)acrylamide, and Stalin the e up to 100% is preferable amount units according to formulas I and II.

Alternative cationic polymer may be a polymer, subjected aromatic modifying agent containing an aromatic group. Suitable modifying agents of this type include benzylchloride, benzylbromide, N-(3-chloro-2-hydroxypropyl)-N-benzyl-N,N-dimethylammoniumchloride and N-(3-chloro-2-hydroxypropyl)pyridinethione. Suitable polymers for such aromatic modifications include vinyl polymers produced additive polymerization. If the polymer contains tertiary nitrogen, which can be quaternity modifying agent, the use of such agents usually leads to the fact that the polymer becomes cationic. Alternative polymer being an aromatic modifications may be cationic, for example cationic vinyl polymer obtained additive polymerization.

Typically, the charge density of the cationic polymer is in the range from 0.1 to 6.0 mEq/g dry polymer, suitably from 0.2 to 4.0, and preferably from 0.5 to 3.0. Srednevekovaja molecular weight cationic polymer is usually at least about 500,000, suitably above about 1000000, preferably above about 2000000. The upper limit is not critical; it can be about 30000000, usually 20000000 and eligible 10000000.

Cationic vinyl polymer obtained additive polymerizes is her may be in suspension in quantities which can vary within wide limits depending on, inter alia, on the type of suspension, salt content, type of salts, filler content, type of filler, attachment points etc., are Usually cationic vinyl polymer obtained additive polymerization, enter in the number that gives the best sizing, dewatering and retention than is obtained when you enter anionic vinyl polymer obtained additive polymerization. The cationic polymer is usually injected in an amount not less than 0,002%, often at least 0.005 wt.%, with respect to the dry pulp weight, while the upper limit is usually 1.0% and suitably 0.5 wt.%.

Anionic polymer additive obtained by polymerization

In addition to the above cationic vinyl polymer obtained additive polymerization containing aromatic units in the cellulose suspension is injected anionic polymer having srednevekovoy molecular weight in the range of from about 6,000 to about 100,000 selected from the group consisting of vinyl polymers, additive obtained by polymerization, and condensation polymers. The anionic polymer may be linear, branched or crosslinked, more suitably essentially linear and are usually water-soluble or water-dispersible. Anionic polymer, exceptthat can be homopolymer or copolymer containing at least two different types of monomers. Preferably the anionic polymer is a vinyl polymer obtained stepwise polymerization, having srednevekovoy molecular weight of from about 6,000 to about 100,000. Suitable anionic polymers derived additive polymerization, are polymers obtained from the reaction mixture containing vinyl unsaturated monomers, preferably vinyl unsaturated monomers containing aromatic units having one or more anionic groups or groups that become anionic in aqueous solutions, suitably by at least one sulphonate group. Examples of anionic groups attached to the vinyl unsaturated monomers are phosphate groups, phosphonate groups, sulfate groups, sulfonic, sulfate groups, carboxyl groups, carboxylate groups, such as groups of acrylic acid, methacrylic acid, ethylacrylate acid, crotonic acid, basis of itaconic acid, maleic acid or their salts, alcoholate groups, maleic acid and phenolic groups, i.e. the replacement family and nattily. Groups bearing an anionic charge, usually salts are alkali metal, alkaline earth metal or ammonium. Anionic VI the sludge polymer, the obtained additive polymerization may equally contain cationic groups, such as monomers having a cationic group, although preferably only ionic groups present in the vinyl polymer obtained stepwise polymerization, are anionic. Preferred anionic groups are from linear to aromatic monomers with vinyl (ethylene) unsaturation, such as styrene, i.e. styrelseledamot. If anionic polymer additive obtained by polymerization, is a copolymer, the said polymer can be obtained from the reaction mixture containing the non-ionic vinyl unsaturated monomers, such as acrylamide, (meth)acrylamide. Anionic vinyl polymer obtained additive polymerization may contain from about 20 mol.% to about 100 mol.% anionic monomers containing at least one anionic charge.

Suitable anionic condensation polymers having srednevekovoy molecular weight in the range of from about 6,000 to about 100,000, are condensed from an aldehyde, such as formaldehyde, with one or more aromatic compounds containing one or more anionic groups, and optionally other comonomers used in the polycondensation, such as urea and melamine. Examples of suitable aromatic compounds, the content is related anionic group, include benzene and naphthaleneamine compounds containing anionic groups, such as phenolic compounds, and Nataliya compounds containing anionic groups, such as phenol, naphthol, resorcinol and its derivatives, aromatic acids and their salts, such as phenol, phenol, nattylove and Nataliya acid and salt, usually, sulfonic acids and sulfonates, such as benzosulfimide and sulfonate, killswitches and sulfonates, naphthalenesulfonate and sulfonate, phenolsulfonate and sulfonate. Examples of suitable anionic condensation polymers include anionic benzylideneamino and naphthaleneamine condensation polymers, preferably naphthalenesulfonates and naphthalenesulfonates condensation polymers.

Srednevekovaja molecular weight anionic vinyl polymer obtained additive polymerization, and condensation polymer is in the range from about 60,000 to about 100,000. The lower limit is suitably from about 7000, preferably from about 8000, preferably from approximately 15,000, preferably from about 25,000, while the upper limit is suitably up to about 80000, preferably up to approximately 75,000, preferably up to about 45000, preferably up to about 40,000. Any combination of lower and upper limit can b the th preferred interval. If the anionic polymer is a vinyl polymer obtained additive polymerization, the preferred interval srednevekovoi molecular weight is from about 10,000 to about 100,000, more preferably from about 15,000 to approximately 75,000, most preferably from about 25,000 to about 45000.

The anionic polymer may have a degree of anionic substitution DSAranging in a wide range depending, among other things, on the type of polymer; DSAis usually from 0.01 to 2.0, suitably from 0.02 to 1.8, and preferably from 0.025 to 1.5; and the degree of aromatic substitution DSOmay be from 0.001 to 1.0, usually from 0.01 to 1.0, suitably from 0.02 to 0.7, and preferably from 0.025 to 0.5. If anionic polymer contains cationic groups, the degree of cation substitution DSCmay be, for example, from 0 to 0.2, suitably from 0 to 0.1, and preferably from 0 to 0.05; and the anionic polymer has a total anionic charge. Usually the density of the anionic charge of the anionic polymer is in the range from 0.1 to 6.0 mEq/g dry polymer, suitably from 0.5 to 5.0, and preferably from 1.0 to 5.0.

The anionic polymer may be in suspension in quantities which can vary depending on, among other things, on the type of raw materials, salt content, type of salts, filler content, type of filler, precise and introducing etc. Usually anionic polymer is administered in an amount which gives the best sizing, dewatering and retention than is obtained when not providing the introduction of the anionic polymer, is injected cationic vinyl polymer obtained additive polymerization. Anionic polymer is usually injected in an amount not less than 0.001 wt.%, often at least 0.005 wt.%, with respect to the dry pulp, whereas the upper limit is typically 3.0 wt.% and are eligible to 1.0 wt.%.

In accordance with one preferred variant of the present invention the cationic vinyl polymer obtained additive polymerization containing aromatic units may be provided as an aqueous composition, suitably an aqueous solution, preferably containing additional cationic polymers, such as synthetic cationic polymers, and polymers found in nature. Suitable synthetic cationic polymers are vinyl polymers, additive obtained by polymerization, such as acrylamidoethyl polymers or galatsaray polymers. Other synthetic cationic polymers include cationic condensation polymers, such epigallocatechin polymers, such as polymers formed by the interaction of aliphatic amines and epichlorohydrin, polyamidoamine polymers, polyethylenimine of polim the frames. Preferred natural cationic polymers are cationic polysaccharides, in particular cationic starch and cationic starch with aromatic substitution. The aqueous solution preferably contains a cationic vinyl polymer obtained additive polymerization containing aromatic units in vast quantities, i.e. at least 50 wt.%, although the effects are present at much lower levels, falling to number not less than 10 wt.%. Other cationic polymers mentioned in this paragraph can also be entered separately.

In accordance with another preferred variant of the present invention, the suspension is injected inorganic microdispersed materials, such anionic particles containing silicon oxide, polysilicon acid and clay smectite type. Inorganic anionic microdispersed material may be injected into the suspension separately, or preferably it is contained in the aqueous compositions containing anionic polymer.

Furthermore, the method can also be used in obtaining paper and paperboard from pulp suspensions having a high conductivity. In such cases, the conductivity of the suspension, which is dewatered on a wire grid, is usually not less than 1.0 MS/cm, suitably not less than 2.0 MS/cm and preferably at least 3.5 MSM/see PR the project can be measured by standard equipment, such as, for example, the device WTW LF 539 supplied by the company Christian Berner. The above values are eligible is determined by measuring the conductivity of the pulp suspension which is served or is present in the paper machine headbox, or, alternatively, by measuring the conductivity of white water obtained by dewatering the suspension. High levels of conductivity mean high content of salts (electrolytes), which may be due to the materials used for production of raw materials, various additives introduced into raw materials, fresh water supplied in the method, etc. in Addition, the salt content is usually higher in the ways in which white water is heavily recycled, which can lead to significant accumulation of salts in the water circulating in the way.

The invention is further illustrated by the following examples, which, however, is not intended to be limiting thereof. Parts and percentages relate to mass parts and wt.% in relation to the dry fibers, respectively, unless otherwise noted. All connections input when loading, calculated as dry material, unless otherwise noted. In the examples of good holding shows at low turbidity in the white water, i.e. fines and filler remain in the molded sheet. Turbidity is below 120 is acceptable, and below 90 I have is in this series of experiments, excellent. The rate of dehydration should also be low. The sizing of the paper is determined by the contact angle of water drops on the paper. The wetting angles greater than 80 degrees through 10 indicate good sizing.

Example 1

Used pulp weight (3%) is 80:20 mixture of Kraft pulp from hard/soft wood. In the pulp weight enter the crushed filler calcium carbonate(GCC) (KIC)) with the concentration of the filler 40% on a dry solid. The resulting composition was diluted to 0.3% before introduction of additional chemicals. Chemical additives are expressed as % of dry solid matter in the composition.

In this example, use two pieces: one with low conductivity of 500 Ás/cm (composition I), the other having a high conductivity of 4.0 Ás/cm (composition II). Conductivity regulate the addition of sodium sulfate. In the composition of the injected dispersion containing traditional sizing substance of the dimer setena and 1% cationic starch. After these introductions introduce or 0.1% of the aromatic cationic polyacrylamide having benzyldimethylammonium group ((A-FRAMES) (A-PAM), or 0.1% of traditional nonaromatic cationic polyacrylamide ((P-FRAMES) (T-PAM)before introducing or 0.1% of Zola silicon oxide, or 0.1% of anionic polystyrenesulfonate ((PSS)(PSS)), having the th srednevekovoy molecular weight of 70000. The entered number of compounds listed in tables I and II. Retention characteristics and dehydration molded compositions appreciate the time dimension dehydration using a dynamic drainage analyzer (DDA unit). A lower value in this experiment means better efficiency. Retention assessed by measuring the turbidity of white water turbidity meter 156 from the company Novasin. Lower turbidity value means a higher retention of solid particles in DDA device. In addition, the sizing of the molded, dried and utverzhdenii paper evaluated by measuring the contact angle of water through 10 with using the device for determining the dynamic absorption and contact angle (DAT) from the company Fibro Systems. A higher value of the contact angle means the best efficiency sizing.

td align="center"> 0,2
Table I
Composition II (high conductivity)
ExperimentThe amount of the dimer of ketene (kg/ton dry pulp)Type cationic polyacrylamideType anionic linkTurbidityObeso accommodations (C)Angle SMA-zivania through 10 (C)
Control*NoNo3907,8Below 10
10,2T-PAMThe Sol of silicon oxide816,9229,6
20,2A-PAMPSS474,5444,6
30,3T-RAMThe Sol of silicon oxide906,6480,8
40,3A-PAMPSS434,4784,6
50,4T-PAMThe Sol of silicon oxide906,77to 89.9
60,4A-PAMPSS474,4794,4
*Neither cationic polyacrylamide or anionic compound is not entered, other conditions are the same as for experiments 1 and 2.

As shown in table I, the introduction of a cationic vinyl polymer obtained additive polymerization containing aromatic units and anionic vinyl polymer obtained additive polymerization, significantly increases not only dehydration and Ude the lid, but also the efficiency of the sizing.

Table II
Composition I (low conductivity)
ExperimentThe amount of the dimer of ketene (kg/ton dry pulp)Type cationic polyacrylamideType anionic linkTurbidityObeso accommodations (C)Angle SMA-zivania through 10 (C)
Control*0,3NoNo4205,6Below 35
10,3T-PAMThe Sol of silicon oxide1004,883,3
20,3A-PAMPSS763,5of 87.8
*Neither cationic polyacrylamide or anionic compound is not entered, other conditions are the same as for experiments 1 and 2.

Example 2

Use. the same composition as in example 1, but in this example, the conductivity of the composition is adjusted to 400 Ás/see

Sizing dispersion, the same as in example 1, is introduced into the composition, followed by the introduction of cationic starch. Osinovka for sizing is 0.03% (calculated as active dimer of ketene on a dry composition for cationic starch - 1,0%. After these introductions impose 0.1% aromatic cationic polyacrylamide having benzyldimethylammonium group, before the introduction of 0.07% anionic polystyrenesulfonate with different srednevekovoy molecular weight as indicated in table III, and anionic naphthalenesulfonate respectively. Input connections are shown in table III. Retention characteristics and dehydration molded compositions appreciate the time dimension dehydration using DDA unit. Retention assessed by measuring the turbidity of white water turbidity meter 156 from the company Novasin. In addition, the sizing of the molded, dried utverzhdenii paper evaluated by measuring the contact angle of water through 10 using a DAT device.

Table III
ExperimentSrednevekovaja molecular weight anionic polymerTurbidityDehydration (C)The wetting angle through 10 (C)
Control *No125of 5.4Below 30
18000278of 5.0591
2200002754,9594
3350001564,89of 92.7
4750001504,0388
51000001473,8285
67800001303,1769,2
1)polystyrenesulfonate;2)naphthalenesulfonate.

*Neither cationic polyacrylamide or anionic compound is not entered, other conditions are the same as for experiments 1-6.

Experiments 1-5 correspond to the present invention, i.e. anionic polymer has srednevekovoy molecular weight in the range of from about 6000 to 100000. As can be seen from table III, the effectiveness of the ring is greatly increased, while at the same time the characteristics of turbidity and dehydration are high for experiments 1-5 compared with the control. In addition, when comparing experiment 6 experiments 1-5 (last five correspond to the invention) shows that the effectiveness of the sizing is much more, while at the same time turbidity still indicates good retention. In addition, the wetting angle of 69.2, as obtained in experiment 6, is unacceptable is th degree of sizing. Thus, the overall characteristics of experiments 1-5 in relation to retention, dehydration, and several sizing clearly exceeds the experiment 6.

1. The method of producing paper or paperboard, including obtaining a suspension containing cellulosic fibers and at least a sizing substance that interacts with cellulose selected from the group consisting of ketonovyh dimers and anhydrides of acids, dehydration specified suspension from forming in the sheet of paper, characterized in that the suspension is injected cationic vinyl polymer obtained additive polymerization containing aromatic units and anionic vinyl polymer obtained additive polymerization with srednevekovoy molecular weight in the range of from about 6000 to about 100000.

2. The method according to claim 1, wherein the anionic polymer has srednevekovoy molecular weight in the range of from about 6000 to about 80000.

3. The method according to any one of claims 1 and 2, characterized in that the anionic polymer additive obtained by polymerization, contains aromatic monomers.

4. The method according to claim 3, characterized in that aromatic monomers have at least one sulphonate group.

5. The method according to claim 1, characterized in that the anionic polymer additive obtained by polymerization is polistirolo the methanesulphonate.

6. The method according to claim 1, characterized in that the anionic polymer is injected into the slurry in an amount of roughly 0.005 to about 1.0 wt.% with respect to the dry pulp weight.

7. The method according to claim 1, characterized in that the cationic vinyl polymer obtained additive polymerization containing aromatic units, has srednevekovoy molecular weight at least about 500,000.

8. The method according to claim 1, characterized in that the cationic vinyl polymer obtained additive polymerization, obtained from the reaction mixture containing from about 1 to about 99 mol.% cationic monomer having an aromatic group.

9. The method according to claim 1, characterized in that the cationic monomer having an aromatic group represented by the formula (I)

in which R1represents N or CH3;

R2and R3represent independently from each other hydrogen or alkyl group having from 1 to 3 carbon atoms;

A1represents O or NH;

B1represents alkylenes group having from 2 to 8 carbon atoms;

Q represents a Deputy containing aromatic group;

X-is an anionic counterion.

10. The method according to claim 1, characterized in that the cationic poly vinyl is EP, the obtained additive polymerization containing aromatic units, enter the amount from 0.002 to 1.0 wt.% with respect to the dry pulp weight.

11. The method according to claim 1, characterized in that the suspension containing cellulose fibers, has a conductivity of at least 1,0 MSM/see



 

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26 cl, 5 tbl, 3 ex

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41 cl, 6 tbl, 6 ex

The invention relates to the technology of making paper lichtovannaya

The invention relates to the production of compositions for paper sizing and can be used in the paper industry

Fixer for mustard // 2222351
The invention relates to pharmaceutical industry and relates fixer for mustard plasters containing emulsifying substance as an adhesive component in the amount of 1.0-30.0 wt.h., the filler in the amount of 1.0-30.0 wt.h., water as solvent a to 100 wt.h

FIELD: polymers.

SUBSTANCE: claimed method includes polymerization of one or more water soluble monomers in aqueous salt solution in presence of polymer dispersant, wherein polymer dispersant represents copolymer of monomer (M) mixture containing at least one cationic monomer and at least one monomer, such as tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate or monomer of general formula I wherein R1 is hydrogen or methyl; R2 is hydrogen or C1-C2-alkyl; R3 is hydrogen, C1-C4-alkyl, phenyl or benzyl; n = 1-4; x = 1-50, and monomer (M) mixture essentially having no water insoluble monomers; and/or polymer dispersant may be obtained by monomer (M) mixture polymerization in reaction mixture essentially having no organic solvents. Also disclosed are aqueous polymer dispersion and application thereof as retention agent in paper production, as thickening agent or agent for soil amelioration. Method for paper production from aqueous suspension includes addition of abovementioned polymer dispersion.

EFFECT: polymer dispersion of high stability, high active substance content, low cationic charge, and good retention characteristics.

FIELD: paper industry.

SUBSTANCE: aqueous composition includes 0.01 to 45 % by weight of anionic organic polymeric particles and silica-based colloidal anionic particles at weight ratio between them from 20:1 to 1:50. Silica-based colloidal anionic particles are prepared by modifying silica with aluminum or amine. Anionic organic polymeric particles are prepared by polymerization of ethylenically-unsaturated monomers with multifunctional ramification agents and/or multifunctional cross-linking agents. Composition is prepared by combining the two types of particles. Papermaking method comprises adding above-prepared composition to pulp composed of cationic polymer fibers.

EFFECT: imp drying and retention properties of aqueous composition.

16 cl, 4 tbl, 4 ex

FIELD: polymer materials and papermaking industry.

SUBSTANCE: invention relates to aqueous silicon-containing composition containing anionic organic polymer comprising at least one aromatic group and silica-based anionic particles in aggregated form or microgel form. Anionic organic polymer, in particular, contains at least one aromatic group and silica-based anionic particles in amount at least 0.01% of the total mass of composition. Composition contains essentially no sizing substance capable of reacting with cellulose, whereas anionic organic polymer containing at least one aromatic group is not naphthalenesulfonate-formaldehyde condensate. Invention also relates to methods for preparing the composition and to utilization thereof as a substance providing dehydration and retention in paper making process. Invention further relates to a paper making process using aqueous suspension containing cellulose fibers and optionally filler, wherein aqueous silicon-containing composition and at least one charged organic polymer are added to pulp.

EFFECT: improved dehydration and/or retention in paper making process and increased storage stability.

20 cl, 4 tbl, 4 ex

FIELD: pulp-and-paper industry, in particular, sizing of paper with the use of aqueous composition.

SUBSTANCE: method involves producing aqueous composition of cellulose filaments and dehydrating paper web; adding aqueous composition to cellulose suspension, said aqueous composition comprising sizing substance aggregates; producing aqueous composition by mixing in any order before adding into aqueous suspension of aqueous solution containing at least one coagulant and aqueous dispersion containing sizing substance. Zeta-potential of composition is below 20 mV.

EFFECT: increased efficiency and simplified method.

26 cl, 5 tbl, 3 ex

FIELD: paper-and-pulp industry.

SUBSTANCE: process of manufacturing cellulose products such as paper articles is accomplished by simultaneously or continuously adding at least one aluminum compound and at least one water-soluble silicate, in particular at least one product of reaction of monovalent cation silicate with bivalent metal ions, to fluid cellulose pulp such as paper pulp. Compositions are also described comprising at least one aluminum compound and at least one water-soluble metal silicate and cellulose products including at least one water-soluble metal silicate complex.

EFFECT: improved retention and drainage allowing manufacture of high-quality cellulose products.

25 cl, 6 tbl, 27 ex

FIELD: inorganic chemistry.

SUBSTANCE: invention relates to composition containing water-soluble silicate complex of general formula (1-y)M2O*yM'O*xSiO2, wherein M is monovalent cation; M' - bivalent cation; x = 2-4; y = 0.005-0.4; y = 0.001-0.25. Method for production of said composition includes mixing of silicates with monovalent and bivalent cations.

EFFECT: composition useful in production of cellulose sheet.

23 cl, 17 ex, 18 tbl

The invention relates to aqueous sols on the basis of silicon dioxide, a process for the production of sols on the basis of silicon dioxide and methods of producing paper that sols are used as additives

The invention relates to water solu containing particles on the basis of silicon dioxide, to a method for producing particles on the basis of silicon dioxide and a method for producing paper

The invention relates to a rheology modifiers to achieve the thickening effect, regulating the expiry of water retention and other properties of aqueous systems
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