Paper making method

FIELD: textile, paper.

SUBSTANCE: method relates to paper production and can be used in pulp-and-paper industry. Method involves the use of cellulose suspension from cellulose fibres and fillers (optional), dehydration of cellulose suspension on grid or sieve so that a sheet can be formed. Then the sheet is dried. In this method there used is polymeric addition which includes ethylenically unsaturated monomer soluble in water or potentially soluble in water, and ethylenically unsaturated monomer containing a reactive group. The latter represents an epoxy group. The polymeric addition used has molar weight which is less than one million. Polymer is obtained from mixture of monomers, which includes acrylamide and glycidyl methacrylate. Thus, the obtained polymer is used as an addition for increase of paper durability in dry condition, in wet condition, as reagent for internal paper sizing and for surface sizing.

EFFECT: increasing paper durability.

17 cl, 2 tbl, 3 ex

 

The present invention relates to a method of manufacturing paper or paperboard. In particular, the present invention relates to improvements in paper strength in wet and dry condition. The present invention also relates to improved methods of sizing paper in bulk and surface sizing.

It is known that the strength characteristics of the paper depend on the strength of the individual cellulose fibers and the ability to form enduring bonds between the cellulosic fibers and from grid cellulose fibers forming a sheet of cellulose. Low quality cellulose fibres can lead to poor strength characteristics. In addition, non-uniform distribution of cellulose fibers, which results in poor molding, also affects the strength of the formed sheet of cellulose.

You know the addition of polymer additives to improve and strength in the wet state during the manufacture of paper, and strength in the dry state are molded so the paper. Typically, such a commercially available polymer additives include natural, modified or partially synthetic water-soluble polymers, such as cationogenic starches, anionic starches, sodium carboxymethyl cellulose, polyacrylamides, anionic polyacrylamides, niskama colerne cationogenic polymers, such as PolyDADMAC (diallyldimethylammoniumchloride), polyamideimides, polyamideimides, polydicyandiamide.

In US-A-3311594 disclosed receipt of aminopolyamide-epichlorhydrine (APAA) resins having high strength in the wet state. These resins receive by the reaction of epichlorohydrin with aminopolyamide and resin APAA bad can be stored in a concentrated form due to the formation of gels, although to a lesser extent than resin GPA (copolymers pixilang of acrylamide with diallyldimethylammoniumchloride). For this reason, reducing the amount of solids in order to reduce the gelation of the resin APAA usually diluted.

Resins based on copolymers pixilang of acrylamide with diallyldimethylammoniumchloride used as a means of increasing the strength of the paper in a dry condition and a temporary increase strength in the wet state. In US-A-4605702 described getting supplements to increase strength in the wet state by glyoxalase acrylamide copolymer, having a molecular weight of approximately from 500 to 6000. The obtained resins have limited stability in aqueous solution and after a short storage even at elevated temperatures to form gels. Therefore, these resins are usually supplied in the form of a relatively dilute aqueous races the thieves, containing only about 5-10 wt.% the resin.

In US-A-5783041 described method for improving the strength characteristics of the paper in a dry condition by adding to the fibrous mass during the manufacture of paper of a solution of a mixture of resins containing aminopolyamide-epichlorhydrine resin, pixillion acrylamide-diallyldimethylammoniumchloride resin and cationogenic resin with a high charge density.

In US-A-3556932 described water-soluble glyoxaline acrylamide polymer agents to increase strength in the wet state. These agents increase the strength in the wet state is made of polymers having a molecular mass less than or equal to about 1000000, although preference is given molecular mass equal to less than about 25,000. These polymers are injected into reaction with glyoxal in a dilute aqueous solution for injection in polymer groups CONHCHOHCHO and to increase the molecular weight of the polymer by crosslinking glyoxal. Low molecular weight polymers and diluted solutions are required for incorporation into the polymer is not less than 6% of groups CONHCHOHCHO without his strong crosslinking or gelation, otherwise the polymers will not be suitable for increasing the strength in the wet state. Even at such low concentrations of solids (thinning) stitching lasts and limits the shelf life of the product. E.g. the measures commercially available products are supplied in the form of solutions containing 10% solids, form gels in about 8 days at room temperature.

In US-A-5041503 attempt to overcome the shortcomings pixillion polyacrylamide by their preparation in the form of microemulsions. Argue that in the microemulsions of the polymer molecules are separated, which prevents the stitching and allows the use of polymers with higher molecular masses. Argue that these polymers are suitable for imparting increased strength in the wet and in the dry state in the production of paper, even if these polymers are crosslinked.

In the publication Takuya Kitaoka et al, entitled "Novel paper strength additives containing cellulose binding domain of cellulase", J Wood Sci (2001) 47: 322-324 described covalently bind proteins containing bind to cellulose domain for anionic polyelectrolytes, modified so that they are reactive to proteins. Anionic polyelectrolytes contain carboxypropyl who are unable to engage in a direct reaction with the protein, and their entering into the reaction with carbodykitstore.com. Then the treated reaction product is combined with the protein containing the binding to cellulose domain, and get a polymer covalently linked to protein. Discovered that as an additive to increase the strength in a dry or what about the wet state, the reaction product is less effective than the usual additives to increase strength in dry and wet condition.

Abstract in Chemical Abstracts (accession number 2004: 222096) described disclosure, similar to that shown in the publication Journal of Wood Science (2001) 47: 322-324.

In recent years there has been a trend towards the regeneration process water used in the production of paper, so that a significant part of the treated fibrous mass of water returned to the process cycle, which reduces the load on the environment due to pollution of watercourses, as well as by reducing the consumption of pure water in the process cycle. The regeneration process water leads to the accumulation of ionic substances such as anionic waste, including lignosulfonates. Therefore, in closed systems, the content of ionic substances in the process water is much greater. It was found that in systems with closed loop conventional ionic resin, designed to increase strength in the dry or in the wet state using electrostatic attraction, are less efficient.

Although conventional nonionic resin, designed to increase strength in the dry and in the wet state, does not adversely impact large content of electrolytes in the production systems of paper with closed circuit, such obionyeaso not as effective as ionic additives used in the production systems of the paper, in which the regeneration process water is held to a lesser extent.

The present invention relates to a method for improving paper strength in a dry condition and strength in the wet state during paper production, in which additives are used, which are more efficient than the above products used in the prior art. The present invention also relates to a product that can be used as an agent for paper sizing in the mass or surface sizing in the manufacture of paper.

The present invention relates to a method of making paper by using the pulp suspension comprising cellulose fibres and optional fillers, dewatering the pulp suspension on the grid or screen to form a sheet and drying the sheet in which the technology is incorporated polymeric additive, in which the polymer additive is a polymer comprising Ethylenediamine water-soluble or potentially water-soluble monomer and ethyleneamines monomer containing a reactive group.

According to the invention it has been unexpectedly found that the polymer additive is effective for improving the strength of molded paper in a dry condition. Cu is IU, the additive also improves the strength in the wet state in the manufacture of paper. The additive can also be used as an agent for paper sizing in the mass, if it is used on the wet stage of the paper production or as agent for surface sizing of paper, if it is applied to the specified molded sheet.

Ethyleneamines the monomer containing the reactive group may be any suitable monomer that will copolymerisate with water-soluble or potentially water-soluble monomer. The reactive group may be any suitable reactive group, which preferably must be able to interact directly with hydroxy groups. In particular, it must be able to interact directly with the hydroxyl groups of cellulose. The ability to interact directly means that under suitable conditions, the reactive group will interact directly with at least one group of the cellulose fibers and that does not require chemical modification group to make it reactive with respect to cellulose fibers. Particularly suitable reactive groups include epoxy, isocyanate, aminotetraline group. is particularly suitable monomer is such that which contains reactive groups, including glycidylmethacrylate, glycidylmethacrylate, allylglycidyl ether, N-methylolacrylamide and 3-izopropenilimidazolom. Of them, especially preferred are glycidylmethacrylate and glycidylmethacrylate.

Soluble in water ethyleneamines monomer preferably has a solubility in water that is at least 5 g of the monomer in 100 ml of water at 25°C. When the monomer is potentially soluble in water, it can be modified, for example, after polymerization and to obtain Monomeric component that is soluble in water, for example, having the above solubility.

Suitable water-soluble or potentially water-soluble monomers selected from the group comprising acrylamide, methacrylamide, N-alkylacrylate, hydroxyalkyl(meth)acrylates (for example, hydroxyethylacrylate), N-vinyl pyrrolidone, vinyl acetate, vinylacetate, acrylic acid (or its salts), methacrylic acid (or its salts), taconova acid (or its salts), crotonic acid (or salt), 2-acrylamide-2-methylpropanesulfonic acid (or salt thereof), (meth)arylsulfonate acid (or its salts), vinylsulfonic acid (or its salts), dialkylaminoalkyl(meth)acrylate, and Quaternary ammonium or molecular salts with acids, dialkylaminoalkyl(meth)acrylamide and Thursday is Chechnya ammonium or molecular salts with acids and diallyldimethylammoniumchloride (for example, diallyldimethylammoniumchloride). Preferred cationogenic monomers include Quaternary ammonium salt of methyl chloride with dimethylaminoethylacrylate and dimethylaminoethylmethacrylate.

Ethyleneamines monomer containing a reactive group, and is soluble in water ethyleneamines monomer can be obtained synthetically from a suitable source materials and using synthetic catalysts or alternative by biocatalytic conversion of an appropriate substrate, which is able to transform into ethyleneamines monomer. Typically, the substrate is injected into interaction with the biocatalyst and thereby transform the substrate in ethyleneamines monomer containing cellular material and optional components of the fermentation. Alternative ethyleneamines monomer can be obtained as the product of the enzymatic reaction.

Polymeric additives can preferably be obtained from a mixture of monomers containing water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.% ethyleneamines monomer containing a reactive group (defined above). The preferred amount of the monomer containing a reactive group, typically up to 5 mol.%. Typically, the monomer containing the reactive group is the number of not less than 0,0001 mol.%, preferably not less than 0.001 mol.%. The polymeric additive can only be obtained from monomer containing a reactive group, and a water-soluble or potentially water-soluble monomer. Usually water-soluble or potentially water-soluble monomer can be in the amount of up to 99,9999 mol.%, preferably up to 99.999 mol.%.

It may be desirable to include other Ethylenediamine monomers, for example, acrylic esters such as methyl acrylate, methyl methacrylate, acrylate, methacrylate, propylacetate, propylbetaine, n-butyl acrylate, n-butylmethacrylate, isobutylacetate, isobutyronitrile, n-hexylaniline, n-hexyllithium, 2-hexyl acrylate, 2-ethylhexylacrylate, stearylamine and sterilisability; styrene; halogenated monomers such as vinyl chloride and vinylidenechloride. The amount of other monomer is usually up to 50 mol.%, though usually up to 20 mol.%, and more preferably less than 10 mol.%.

More preferably, when the polymeric additive is prepared from a mixture of monomers containing from 50 to 99,995 mol.% water-soluble or potentially water-soluble Ethylenediamine monomer; 0.005 to 2 mol.% ethyleneamines monomer containing a reactive group; and 0 to 50 mol.% another of these is ananassisalsaga monomer. Even more preferably, if the amount of water-soluble or potentially water-soluble monomer is 80, preferably more than 90) to 99,995 mol.% and a number of other ethyleneamines monomer (if it is) is up to 20 mol.% (preferably less than 10 mol.%).

Particularly preferred polymeric additive is prepared from a mixture of monomers including acrylamide and glycidylmethacrylate. Especially preferred is a polymer in which the number of glycidylmethacrylate is the same as indicated above for the monomer containing the reactive group. Particularly preferred polymer contains 0.005 to 5 mol.% glycidylmethacrylate, and the rest is acrylamide.

Polymer additive proposed in the present invention, may have a mass-average molecular weight, component only several thousand, for example, 6000 or 7000 or very high, for example, several tens of millions. However, we found that if the polymer is proposed in the present invention is intended for use as an additive to increase the strength in the dry state in the production of paper, it is preferable that the polymer had a mass-average molecular weight of below one million. More preferably, the polymer had a mass-average molecular what assay, less 500000, more preferably in the range of from 50000 to 300000, and even more preferably from 100000 to 150000.

The polymeric additive can be obtained by combining the above monomers with a mixture of monomer and subsequent polymerization of the mixture of monomers. Typically, this procedure may include the introduction of the polymerization initiators and/or processing of a mixture of monomers actinic radiation, such as ultraviolet radiation and/or heating the mixture of monomers.

The mixture of monomers preferably dissolving or dispersing in an aqueous medium and to enter into the aquatic environment water-soluble initiator to conduct polymerization. The polymerization can be carried out with the help of various systems initiators. For example, water-soluble polymers will usually polymerized using a redox couple initiator, when the radicals generated by mixing the monomer with a redox couple, which includes oxidizing agent and reducing agent. Alone or in combination with other systems initiators typically use thermal initiator, which includes any suitable initiator, which at elevated temperatures allocates radicals. Other systems initiators include photoinitiator and activated by the radiation system and is iciation, when exposed, are formed radicals, leading to polymerization. Other systems initiators are well known and are described in detail in the literature.

Typical redox initiators include reductive reagent, such as sodium sulfite, sulfur dioxide and an oxidizing reagent, such as ammonium persulfate or a suitable peroksosoedinenii, such as tert-butylperoxide etc. In redox initiation can be used to 10000 miscast./million (in recalculation on weight of monomer) of each component of the redox couple. Preferably, each component of the redox pairs contained in the quantity < 1000 miscast./million, typically in the range from 1 to 100 miscast./million, most often in the range of 4 to 50 miscast./million the ratio of the number of oxidizing reagent to the amount of recovery of the reagent may range from 10:1 to 1:10, preferably be in the range of from 5:1 to 1:5, more preferably from 2:1 to 1:2, for example, about 1:1.

The polymerization can be carried out using a thermal initiator, separately or in combination with other systems initiators, for example, redox initiators. Thermal initiators include any suitable initiator that p and elevated temperature allocates radicals, for example, azo compounds such as azobisisobutyronitrile (Abin), 4,4'-azobis-(4-cyanovalerianic acid) (ACVC). Typical thermal initiators are used in quantities of up to 10000 miscast./million, calculated on the weight of monomer. However, in most cases, thermal initiators are used in amounts in the range from 100 to 5000 miscast./million, preferably from 200 to 2000 miscast./million, typically about 1000 miscast./million

The polymeric additive can be obtained in the form of an aqueous solution of the polymer. It can be, for example, relatively concentrated, for example, have a concentration equal to more than 2 wt.%, such as at least 5 or 10 wt.%. Alternative polymer can be obtained in powdered form, for example, in the form of a powder. This can be accomplished by drying the solution containing the polymer, with subsequent grinding of the polymer with the formation of a powdery product. Alternative polymer can be obtained in the form of a gel by polymerization of the monomer solution at a concentration of not less than 30% and usually at least 50 wt.%. The resulting gel can be crushed, dried and then crushed to obtain a powder by conventional technologies, which are described in the literature. Alternative polymer can be obtained in the form of pellets or in the form of an emulsion by reversed-phase polymerization of the monomer in the water-immiscible liquid is spine with the use of the stabilizer polymer. The polymer stabilizer is usually amphipatic stabilizer, for example, derived from hydrophilic and hydrophobic acrylic polymers. Suitable methods are described in the literature, for example, suitable water-immiscible liquid and stabilizers and/or surfactants are described in EP-A-150933 and EP-A-126528. Suitable surface-active agents, non-aqueous liquid and polymer stabilizers are described, for example, in EP-A-128661, EP-A-126528, GB-A-2002400, GB-A-2001083 and GB-A-1482515.

When receiving balls polymers they usually should be mostly dry. Usually mostly dry beads is determined by the particle size of water-immiscible liquid dispersed in the aqueous phase. Often it is desirable that the solid particles were balls having a size of not less than 30 μm, often at least 100 μm, for example, 500 μm or 1 mm or even 2 mm or more. In the case of particles of this size mostly dry particles separated from the water-immiscible liquid by filtration, centrifugation or other conventional methods of separation and after separation can be dried. This additional drying can be performed by exchanging with the solvent, but preferably warm air, for example, in the fluidized bed.

In one preferred embodiment, the present image is the shadow of this polymer additive to include dewatering the pulp suspension. Usually do before dewatering the pulp suspension on the grid or sieve machine and usually before the headbox.

Preferably, when the polymeric additive is an additive to increase the strength in the dry state. If the polymer is used to increase the strength of the paper in the dry state, it is preferable to turn on the wet stage of paper production. Usually polymer additive to increase the strength in the dry state can be entered together with any other components of the raw materials, e.g. cellulose raw material. You can enter it in the capacity to combine components or mixing capacity in the manufacture of paper or thick raw materials to its dilution. Alternative resin to increase strength in the dry state was added to the diluted raw materials. This can be done immediately after dilution thick raw materials or, perhaps, after one of the mixing pumps. The additive can be entered after centrifugal sieve, but to dehydration, but it is preferable to centrifugal sieve.

The polymer to increase strength in the dry state may be added in conventional quantities, for example, equal to not less than 300 g/t and possibly up to 2 kg/ton or more. Typical amounts can be about 1 kg/so

The polymer is proposed in the present invention, may be supplied and used in the underwater solution. In one form, the polymer may be supplied in the form of a relatively concentrated aqueous solution, for example, concentrations of more than 2 wt.%, for example, at least 5 or 10 wt.%. An aqueous solution of polymer can be used directly, or before use it can be thinned to a relatively low concentration, for example, up to 1 wt.% or less, for example, from 0.05 to 0.5%, such as 0.1 wt.%. It is desirable that the polymer was in powdered form, for example, in powder form, but preferably in the form of balls. Powdered polymer can be dissolved in water to obtain an aqueous solution having such a concentration as specified above. In another case, it may be desirable to use a powdered polymer directly in the production of resin to increase strength in the dry state. Preferably, if the crushed polymer is in the form of balls that are directly injected into the production.

Usually in technology tools can be used for dehydration and improve retention of filler in conjunction with other additives, such as, for example, fixative etc. Typical system for dewatering and improve the retention of fillers may consist of a system of particles, such as used in efficient technologies Ciba Hydrocol®, which is described in EP-A-235893.

In another embodiment of the present invention the polymeric additive can be used as a reagent for paper sizing in mass. Usually the characteristics of the polymer mo is but to pick up so, so when the production technology of paper he modified the ability of the fibers contained in the mass of moldable sheet of paper, to absorb water, so they absorb less water. This is important because this eliminates unacceptable humidity and water absorption of the paper.

When used as a reagent for paper sizing in the mass of the polymer is usually included in the diluted raw materials, but it can be in the thick of raw materials or in any of the components of raw materials. It may be desirable inclusion of polymer in the composition for sizing paper in bulk. Such a composition is by its nature can be cationogenic that she had a greater affinity for the fibers. Also, it may be desirable that the polymer was cationogenic and this can be achieved by obtaining cationogenic synthetic polymer component, in which the water-soluble Monomeric component includes cationogenic monomer.

The polymer described in the present invention, when introduced into a suspension of pulp in paper production can mainly be simultaneously act as additives to increase strength in the wet state, and also as a reagent for paper sizing in mass.

In yet another embodiment, the present invention polymeric additive causing the surface formed of a sheet of cellulose. Typically, the additive is applied to the sheet of pulp after the pulp suspension is dewatered on a grid or sieve machine. It is preferable to do it before or during the stage of drying. In this embodiment of the present invention it is preferable that the polymer additive formed a surface coating of at least one, and usually on both surfaces of a sheet of cellulose.

In a preferred embodiment, the polymeric additive when applied to the surface of a sheet of cellulose is a reagent for surface sizing. Usually this is achieved by applying a polymer to the surface of a sheet of cellulose. When using the polymer as a reagent for surface sizing of paper, it is preferably applied to the surface of a sheet of cellulose during or prior to drying. Surface sizing of the paper causes the paper surface absorbs less water. When using polymer proposed in the present invention can provide significant improvements in the manufacture of paper taped surface.

Reagent for surface sizing paper can be applied to a sheet of cellulose in the usual quantities. Usually they constitute not less than 50 g/t of dry paper) and can be up to 2 g/t of dry paper), preferably in the range from 300 g/t to 1.5 kg/so

In more the positive embodiment, the present invention relates to a polymer, which is obtained from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably up to 5 mol.% goldlenovo monomer, which is Ethylenediamine monomer containing glycidyloxy group, where the polymer has a mass-average molecular weight equal to less than one million.

The polymer may have any of the above features, as described for polymer additives used in paper production. The polymer is particularly suitable for use as an additive in the manufacture of paper. It, for example, can be used as an additive to increase the strength in the dry state, additives to increase strength in the wet state, the reagent for paper sizing in mass or as a reagent for surface sizing of paper.

According to the invention have found that this polymer is particularly effective if the mixture of monomers from which the polymer comprises acrylamide or methacrylamide.

Particularly preferred polymers include glycidylmethacrylate or glycidylmethacrylate as goldlenovo monomer.

In a preferred form, the polymer includes at least 99.9 mol.% acrylamide or methacrylamide and up to 0.1 mol.% glycidylmethacrylate or glitzy is immutability. More preferably, the polymer was obtained from a mixture of monomers, which includes from 99,990 up to 99.999 mol.% acrylamide or methacrylamide 0.001 to 0.01 mol.% glycidylmethacrylate or glycidylmethacrylate. Especially preferred is a content of acrylamide or methacrylamide constituting 99,990 up to 99,995 mol.%. Especially preferred content glycidylmethacrylate or glycidylmethacrylate range from 0,005 to 0,010 mol.%.

The polymer is proposed in the present invention, may have a mass-average molecular weight, component only several thousand, for example, 6000 or 7000 or very high, for example, several tens of millions. However it was found that if the polymer is proposed in the present invention is intended for use as an additive to increase the strength in the dry state in the production of paper, it is preferable that the polymer had a mass-average molecular mass of less 500000, more preferably in the range of from 50000 to 300000, and even more preferably from 100000 to 150000.

A preferred polymer is characterized by a combination of a specific range of molecular masses and the relationship between the amount of acrylamide or methacrylamide to the number of glycidylmethacrylate or glycidylmethacrylate. Preferably, if the polymer contains not less than 99.9 mol.% acrylamide and do,1 mol.% glycidylmethacrylate or glycidylmethacrylate and has a mass-average molecular weight, equal to 100,000 to 200,000, preferably 130,000 to 150,000.

The polymer can be obtained by the above-described technology of polymer additives used in the manufacture of paper.

The following examples illustrate the present invention.

Examples

1. The method of analysis

The polymers are analyzed by exclusive chromatography (ACH) using columns TSK PWXL (G6000+G3000+percolone) or equivalent. Mobile phase is 0.2 M solution of sodium chloride (NaCl) with the addition of 0.05 M potassium hydrogen phosphate (K2NRA4) in purified water, which is pumped through the system at a nominal flow rate of 0.5 ml/min

Polymers weakly absorb UV radiation with a wavelength equal to 280 nm, but strong absorption at 210 nm due to the presence of the carbonyl chromophore. Molecular mass and molecular mass distribution of polymers is determined by the absorption at 210 nm using a calibration columns with set standards of sodium polyacrylate with known characteristics of molecular masses. Measure the retention time of each standard in the system EACH and build the dependence of the logarithm of the intensity of the peak molecular weight from the retention time.

2. Synthesis of polymer

General methods

1. In a suitable vessel for carrying out reactions put water and pentanitrate salt of the diethyl who triaminotoluene acid (DETAPA).

2. The temperature of the contents promote and support equal to 80°C.

3. In the vessel for carrying out reactions add initiator (1).

4. Immediately after the addition of initiator (1) in a vessel for carrying out reactions added to the monomer solution and the initiator solution (2).

5. After the addition of all the monomer and initiator contents of the vessel for carrying out reactions continue to stir for another 30 min, keeping the temperature set to 80°C.

Synthesis of copolymer of acrylamide:glycidylmethacrylate (molar ratio 99:1)

3. The manufacture of a sheet of paper manually using polymer reacted with communicating with cellulose domain.

The preparation of the masses

The mass composition of 50:50 length:short fibers prepared with the inclusion of 10% filler concentration of 1.8% and grind to the consistency of grind equal to 45 degrees on the instrument shopper-Rigler.

The study of polymer - tensile strength

The mass is stirred at 1000 rpm and stirring for 30 with added polymer (0.1%) quantity of 1 kg/so

Then the mass is diluted to 0.5% and selected aliquots of 5×300 ml

To each aliquot was added cationogenic polyacrylamide, Percol 182 having a characteristic viscosity, equal to more than 7 DL/g (500 g/t) under stirring at 1500 rpm for 30 s, and then when ablaut bentonite sodium Hydrocol O (2 kg/t) and further stirred at 500 rpm for 15 sec. Then the sheets of paper are made manually using the apparatus of the British Standard Handsheet maker and from each specimen manufacture 5 sheets. From each sheet, cut out a strip (2.5 cm) and a separate strips condition in accordance with the test method Tappi T (standard air conditioning and atmosphere for paper, cardboard, hand-made from the mass of sheets and similar products).

Then air strips are examined in accordance with the test method Tappi T (characteristics tensile strength of paper and paperboard using device Testometric 220D.

The results of studies of polymer

Used polymers are the copolymers of polyacrylamide-glycidylmethacrylate with different content of reactive glycidylmethacrylate links specified in the table below:

No.Content glycidylmethacrylate links, mol. %The content of the initiator,%, calculated on the monomerMolecular weightWeight in the dry state (%)
210,7527900022,9
31119700023,5
40,10,525300024,0
50,10,7521600023,5
60,1114800023,1
70,010,514000022,0
80,010,7511100022,8
90,01115500023,3

Results study characteristics tensile strength:

Sample # Ash content (%) (average)The index tensile strength(average)
Idle (without polymer)10,4946,34
2becomes 9.9756,25
310,0250, 20mm
49,8652,87
5to 9.9157,60
610,0654,40
79,8658,98
89,5950,59
99,7556,45
8 (the pH is brought to 10)9,2950,29

Discovered that the polymeric additive is an effective resin to increase strength in the dry state and it is shown that the copolymers of polyacrylamide-glycidylmethacrylate can act as effective resins to increase about the activity in the dry state.

1. Method of making paper comprising the use of a pulp suspension comprising cellulose fibres and optional fillers, dewatering the pulp suspension on the grid or screen to form a sheet and drying the sheet, which includes a polymer additive, where the polymeric additive is a polymer comprising Ethylenediamine water-soluble or potentially water-soluble monomer and ethyleneamines monomer containing a reactive group, in which the reactive group is an epoxy group, and the polymer has a mass-average molecular weight of below one million.

2. The method according to claim 1, in which the polymer is produced from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably 5 mol.% ethyleneamines monomer containing a reactive group.

3. The method according to claim 1 or 2, in which the polymer is produced from a mixture of monomers including acrylamide and glycidylmethacrylate.

4. The method according to claim 1 or 2, in which the polymer has a mass-average molecular weight equal to less than one million, preferably from 50000 to 300000.

5. The method according to claim 1 or 2, wherein the polymer additive is an additive to increase the strength in the dry state.

6. The method according to claim 1 or 2, wherein the polymer additive is an additive to increase the strength in the wet state.

7. The method according to claim 1 or 2, wherein the polymeric additive is a reagent for paper sizing in mass.

8. The method according to claim 1 or 2, wherein the polymeric additive is applied to the surface of the molded sheet of cellulose, and in which the polymeric additive is a reagent for surface sizing of paper.

9. The polymer, which is obtained from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably up to 5 mol.% goldlenovo monomer, which is Ethylenediamine monomer containing glycidyloxy group, and the polymer has a mass-average molecular weight equal to less than one million.

10. The polymer according to claim 9, in which the mixture of monomers include acrylamide or methacrylamide.

11. The polymer according to claim 9 or 10, in which Picadilly monomer is glycidylmethacrylate or glycidylmethacrylate.

12. The polymer according to claim 9 or 10, in which the polymer includes at least 99.9 mol.% acrylamide and 0.1 mol.% glycidylmethacrylate or glycidylmethacrylate.

13. The polymer according to claim 9 or 10, which has a mass-average molecular weight equal to from 50000 to 300000.

14. The use of poly the EPA as an additive to increase the strength in the dry state in a method of manufacture of paper, in which the polymer is produced from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably up to 5 mol.% goldlenovo monomer, which is Ethylenediamine monomer containing glycidyloxy group, in which the polymer has a mass-average molecular weight equal to less than one million.

15. The use of the polymer as an additive to increase the strength in the wet state in the method of production of paper, in which the polymer is produced from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably up to 5 mol.% goldlenovo monomer, which is Ethylenediamine monomer containing glycidyloxy group, in which the polymer has a mass-average molecular weight equal to less than one million.

16. The use of the polymer as a reagent for paper sizing in the mass production method of the paper, in which the polymer is produced from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably up to 5 mol.% goldlenovo monomer, which is etilen is saturated monomer, containing glycidyloxy group, in which the polymer has a mass-average molecular weight equal to less than one million.

17. The use of the polymer as a reagent for surface sizing of paper in the method of production of paper, in which the polymer is produced from a mixture of monomers comprising at least one water-soluble or potentially water-soluble Ethylenediamine monomer and up to 10 mol.%, preferably up to 5 mol.% goldlenovo monomer, which is Ethylenediamine monomer containing glycidyloxy group, in which the polymer has a mass-average molecular weight equal to less than one million.



 

Same patents:

FIELD: paper; chemistry.

SUBSTANCE: method of cellulose fiber modification is realised in the following manner. Suspension mass of cellulose fibers is prepared. In process of its bleaching cellulose derivative is added in at least one stage of acid bleaching. pH of suspension mass is in the interval from approximately 1 to approximately 4, and temperature - in interval from approximately 30 to approximately 95°C. As cellulose derivative carboxy-alkyl-cellulose is used, for instance, carboxy-methyl-cellulose. From this suspension of bleached fiber mass paper is produced by means of dehydration of this suspension on the mesh with formation of paper.

EFFECT: higher strength in wet condition and softness of paper.

42 cl, 2 dwg, 1 ex

FIELD: polymer materials in paper-and-pulp industry.

SUBSTANCE: invention relates to manufacturing cellulose-polymer composites that can be, in particular, used in production paper or cardboard. Method according to invention providing a composition and manufacturing sheet therefrom followed by drying. In the method of invention, aqueous nanodispersion of polyorganosiloxanes is utilized, which can be introduced into composition or can be deposited onto sheet before drying on size press or after drying of sheet to moisture content not less than 12°.

EFFECT: improved waterproofness, increased inflammation temperature, and improved physicochemical characteristics of material.

4 cl

The invention relates to an agent that increases the strength of paper in the wet state, and the method of its production, and method for producing a paper containing this agent

The invention relates to mixtures of cationic starch with a cationic galactomannan gum, such as husarova gum, gum carob, fenugreek, Greek, etc. that can be used as a means that can help give strength and dehydration in the manufacture of paper

The invention relates to the pulp and paper industry, in particular the production of separator paper, which will find application in electrical industry for chemical current sources with an alkaline electrolyte

The invention relates to the pulp and paper industry

The invention relates to the production of multi-layer waterproof paper and can be used in the pulp and paper industry for paper production for the major layers of decorative paper laminate (DBSP)

The invention relates to the production of multi-layer paper and can be used in the pulp and paper industry for paper production for the major layers of decorative paper laminate

The invention relates to the pulp and paper industry, in particular to methods of producing paper for the inner layers of decorative paper laminates containing phenol-formaldehyde resin

Paper filler // 2345189

FIELD: textile, paper.

SUBSTANCE: filler is designed for paper making and can be used in pulp-and-paper industry. Filler contains calcium salt and cellulose derivative with lattice ionic fractional substitutionality up to approximately 0.65, where filler is essentially free from either cellulose fibre or fibrils or lignocellulose. Filler contains calcium salt and cellulose derivative with lattice ionic fractional substitutionality up to approximately 0.65, where cellulose derivative can contain cationic groups. Besides the invention refers to production process of filler involving mixing the agent substance containing calcium salt and cellulose derivative with lattice ionic fractional substitutionality up to approximately 0.65, essentially without cellulose fibre or fibrils or lignocellulose. Other production process of filler consists in mixing the agent substance containing calcium salt and cellulose derivative with lattice ionic fractional substitutionality up to approximately 0.65, where cellulose derivative contains cationic groups. The invention refers to method for making paper including preparation of aqueous suspension containing cellulose fibre, suspension addition with filler containing calcium salt and cellulose derivative with lattice ionic fractional substitutionality up to approximately 0.65, where filler is essentially free from either cellulose fibre or fibrils or lignocellulose; dehydration of suspension thus making web or paper sheet. The invention also refers to method for making paper including preparation of aqueous suspension containing cellulose fibre; suspension addition with filler containing calcium salt and cellulose derivative with lattice ionic fractional substitutionality up to approximately 0.65, where cellulose derivative contains cationic groups; dehydration of suspension thus making web or paper sheet.

EFFECT: higher sizing efficiency with good drainage, retention and serviceability of papermaking machine.

24 cl, 3 tbl, 4 ex

FIELD: textile fabrics, paper.

SUBSTANCE: composition concern pulp and paper industry and is intended for cellulose-bearing materials surface treatment. The first composition includes modified carbamide - formaldehyde oligomer and in the capacity of modifier is sodium salt of carboxymethyl cellulose. The second composition contains mentioned above components and melamine. The third composition contains components of the first composition and cationic starch.

EFFECT: improving of composition and strength properties of cellulose-bearing materials.

3 cl, 3 tbl, 12 ex

FIELD: soft wares, paper.

SUBSTANCE: compound is intended for pulp materials hydrophobisation and can be used in pulp and paper industry and at paper and board manufacturing. Compound contains modified thallous galipot, paraffin, thallous fatty acids and balancer at defined components ratio. In the capacity of balancer sodium lauryl sulfate, sodium laureth sulfate, cocoamidopropylbetain or cocoamidopropylaminochloride is used.

EFFECT: compound refinement for hydrophobisation of pulp materials, supplying of its hydrophobization efficiency and storage life duration.

5 cl, 1 tbl

FIELD: textiles, paper.

SUBSTANCE: glue is meant for cellulose materials processing and can be used in pulp and paper industry for production of paper and cardboard. The glue contains carbamide, formaldehyde and, as a modifying agent, melamine and cationic starch at certain rate of mixture.

EFFECT: improved quality of glue thanks to the increase in its hydrophobic property and stability.

1 tbl, 1 ex

FIELD: textiles, paper.

SUBSTANCE: glue is meant for cellulose materials processing and can be used in pulp and paper industry for production of paper and cardboard. The glue contains formaldehyde, carbamide, melamine, cationic starch and polyvinyl alcohol at certain rate of mixture.

EFFECT: improved quality of glue thanks to the increase in its hydrophobic property and stability.

1 tbl, 2 ex

FIELD: textiles, paper.

SUBSTANCE: paper or cardboard of improved rigidity and bulk are meant for reproducing equipment and the method refers to production of the said paper and cardboard. The paper or cardboard has the core layer and starch-based layers applied by gluing-up on its both sides forming the uniform canvas of the double-T structure. The layers cover the upper and the lower surface of the central layer with minimal penetration to the central layer. The starch contains the filler spreading to the central layer. The starch has high content of solid products. The mass of the coating layers is 2-10 g/m2. Method for producing paper or cardboard includes the following stages: a) creation of composition containing cellulose fibers and the filler, b) formation of fibrous canvas, c) drying of the fibrous canvas, d) processing by gluing-up both sides of the dried canvas with the starch with filler and e) drying of the fibrous canvas with formation of the three-layer making the uniform canvas material with the double-T structure.

EFFECT: increased quality of paper or cardboard due to increased smoothness, decreased hygroscopic expansivity, improved fold resistance and paper rolling resistance.

30 cl, 2 dwg, 3 tbl, 3 ex

FIELD: inorganic chemistry.

SUBSTANCE: invention covers water soluble sizing compounds providing oil resistance/grease- and waterproofness applied for cellulose materials processing, containing repeated elements including polyamine with at least 3 nitrogen atoms in every repeated monomer element where amides are partially or completely substituted with a. cellulose interacting group resulted from reaction of polyamine and at least one reactive chemical compound selected from number including epihalohydrin, epiorganosulfonates and oxirane implying that interaction with cellulose arises after polyamine reaction or due to further reactivation; b. hydrophilic and hydrophobic fluorine-containing chemical group substituted with alkyl chain containing hydrophilic group; besides cellulose interacting group cross-links polyamine groups, and substance molecular weight Mw is from 10000 to 35000000 daltons determined by gel-penetrating chromatography relative to, polymethylmethacrylate standard. In addition invention covers chemical substance containing polymer composition with product of interaction between fluorocarbon-substituted polyamine of IV structure or epihalohydrin or epiorganosulfonate; method of sized paper production providing oil resistance/grease- and waterproofness (versions); paper production (versions); aqueous dispersion (versions). This substance effectively works providing oil resistant/grease- and waterproof sizing at high temperatures.

EFFECT: sizing compound production providing oil resistance/grease- and waterproofness of cellulose materials.

36 cl, 20 tbl, 125 ex

FIELD: paper and pulp manufacturing.

SUBSTANCE: the present innovation deals with manufacturing paper being of high antimicrobial and fungicidal activity and could be applied for manufacturing paper being resistant to contamination, of high physico-mechanical properties and applied for manufacturing banknotes, bonds, shares and others. The suggested composition includes a filamentous constituent, a filler, a gluing constituent, a biocidal additive as synergistic mixture of polyhexamethylene guanidine and sodium salt of benzoic acid at the ratio being (10-1):(1-10), correspondingly, a moisture-resistant additive, a binding agent and water. Moisture-resistant additive is being epichlorohydrin or urea-formaldehyde resin. Binding agent is being formalin or ammonium salt of titanium chelate and lactic acid. Gluing constituent additionally contains polyvinyl alcohol or sodium salt of carboxymethyl cellulose. The innovation enables to increase antimicrobial and fungicidal activity of the composition mentioned, simplify its application and, also, increases physico-mechanical properties, abrasion resistance and resistance to contamination of the obtained paper.

EFFECT: higher efficiency of manufacturing.

3 cl, 5 ex, 4 tbl

Dispersion // 2309213

FIELD: paper-and-pulp industry.

SUBSTANCE: invention provides aqueous dispersion, method of preparing it, use of dispersion, and a paper manufacturing process comprising internal sizing and surface sizing of paper. Aqueous dispersion contains at least one cellulose-reactive sizing agent selected from group consisting of ketene dimers and multimers, at least one cellulose-unreactive sizing agent, and at least one emulsifier selected from group consisting of oxyalkylene phosphate and sulfate esters and their salts. Dispersion preparation method comprises joining together sizing agents with at least one emulsifier in presence of water to form mixture, which is then homogenized to form aqueous dispersion. Paper manufacturing process comprises forming paper sheet from pulp containing cellulose fibers and depositing said aqueous dispersion thereon. Paper manufacturing process also comprises adding said aqueous dispersion to pulp containing cellulose fibers and dehydrating pulp on screen to produce paper.

EFFECT: increased stability of dispersion and efficiency of outside and internal sizing.

18 cl, 4 tbl, 4 ex

FIELD: production of cardboard for manufacture of packages for liquids.

SUBSTANCE: method involves treating fibrous mass designated for preparing of cardboard with percarbonic acid used in an amount of 0.5-5 kg per t of dry fibrous mass on conversion to 100%-concentration of percarbonic acid; thereafter or simultaneously with indicated treatment process, providing gluing-through by combining resin-based and neutral adhesives; forming cardboard.

EFFECT: reduced moisture-permeability and improved quality of gluing-through of cardboard.

11 cl, 3 tbl, 3 ex

FIELD: medicine.

SUBSTANCE: absorbing cloth from a cellulose fiber contains an admixture of hard wood and soft wood fibers located in the form of mesh structure, including: the set of columnar areas fibers conglomeration with relatively high local density, aggregated by means of set of the connecting areas with lower local density, where orientation of fibers is inclined along a longitudinal direction between the columnar areas interconnected in a such way, where the cloth possesses coefficient of elongation in a cross-section direction, which is at least in 2.75 times higher than relative strength at cloth stretching in a dry condition. The above-stated material is obtained as follows. A water cellulose composition from hard wood fibers is prepared. The composition is moved on a forming tissue in the form of a stream which is let out from a pressure head box with a flow rate. The composition is dehydrated and compacted for manufacturing of a paper for formation of the fibrous layer possessing chaotic distribution of a fiber for paper manufacturing. Packing of the dehydrated fibrous layer possessing chaotic distribution of a fiber on the transporting transferring surface moving with the first rate. Creping of a fibrous layer from the transferring surface on a tape at dryness from 30% to 60% with use of the pattern creping tape. The creping stage is carried out under pressure in a contact zone of the creping tape confined between the transferring surface and the creping tape. Thus the tape is moved with the second speed, lower than speed of the transferring surface. Tape drawing, parametres of a contact zone, speed difference and dryness of the fibrous layer are chosen in such way to crepe the fibrous layer at its removal from the transferring surface and to redistribute on the creping tape with formation of a fibrous layer with mesh structure. Drying of the fibrous layer is performed after. The process is regulated so that coefficient of elongation in a cross-section direction is, at least, approximately in 2.75 times higher than relative strength at stretching of the fibrous layer in a dry condition. Such method allows obtaining a cellulose fibrous layer for products made from thin paper, and also products in the form of towels.

EFFECT: improvement of ready product quality and power consumption decrease.

33 cl, 10 dwg, 22 tbl

FIELD: textile; paper.

SUBSTANCE: method consists of adding to the paper sheets approximately 0.05 pounds/ton to 15 pounds/ton, in accordance with the dry fibers, one or several polymers, functioning as aldehyde, containing amino or amido group, where, at least, 15 molar percent amino or amido group function with one or several aldehydes and where the functionaling aldehyde polymers have a molecular weight of not less than approximately 100000.

EFFECT: increased activity for drying due to a reduction in the amount of polymer.

14 cl, 5 ex

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