37results about How to "Reduce the Cobb value" patented technology

The invention provides a preparation method for a surface sizing agent emulsion. The preparation method comprises the following steps: mixing a cationic polymer with water; adding molten AKD (alkyl ketene dimer) wax and paraffin wax at 70-75 DEG C; and then homogenizing in a condition of 10-25 Mpa, cooling to a temperature below 40 DEG C, and adding glyoxal, so as to obtain the surface sizing agent emulsion, wherein the cationic polymer is prepared by reacting a cationic etherifying agent, chitosan, hydrogen peroxide, silane, acetic acid, sodium hydroxide and a dispersing agent under the action of an initiator; the surface sizing agent emulsion comprises the following components in parts by weight: 80-90 parts of the AKD wax, 10-20 parts of the paraffin wax, 25-100 parts of the cationic polymer, 1-5 parts of glyoxal, and 270-600 parts of water, wherein the total of the AKD wax and the paraffin wax is 100 parts by weight. The surface sizing agent emulsion provided by the invention is a high-performance and environment-friendly product capable of meeting application for papermaking coatings; the product is capable of obviously improving the hydrophobicity of paper, reducing the Cobb value, and improving the surface strength of the paper in case of being applied to surface sizing for the paper.

The invention discloses a surface sizing agent emulsion and its preparation method and use. The preparation method comprises mixing a cationic polymer and water, adding alkenyl succinic anhydride (ASA) and paraffin into the mixture, carrying out stirring homogenization and adding aluminum sulfate into the mixture to obtain the surface sizing agent emulsion. The cationic polymer is an aqueous dispersion prepared through copolymerization of a cationic monomer, a (methyl) acrylate monomer and (methyl) styrene. Gelatin as a dispersant, a cationic-nonionic composite surfactant as an emulsifier and 2, 2'-azobis(amidinopropyl)dihydrochloride as an initiator undergo a free radical emulsion polymerisation reaction to produce the surface sizing agent emulsion. The surface sizing agent emulsion is a high performance and eco-friendly product satisfying papermaking paint use requirements. The surface sizing agent emulsion is used for paper surface sizing, obviously improves paper hydrophobicity, reduces a Cobb value and improves paper surface strength.

The invention discloses a surface sizing agent emulsion and a preparation method and application thereof. The preparation method comprises the following steps: mixing a cationic polymer with water, adding alkenyl succinic anhydride (ASA) and paraffin wax, evenly mixing, and adding aluminum sulfate to obtain the surface sizing agent emulsion, wherein the cationic polymer is prepared from a cationic monomer, starch, hydrogen peroxide, silane and sulfuric acid by reacting under the effect of an initiating agent. The surface sizing agent emulsion is a high performance and environmentally-friendly product meeting use of paper product coatings. The product is applied to coating surface sizing, can significantly improve the hydrophobicity of paper, reduces Cobb value, and improves paper surface strength.

A polymeric dispersant is disclosed. A preparation method of the polymeric dispersant includes mixing maleic anhydride and polyvinyl alcohol, heating the mixture until the mixture is molten, then performing polycondensation, cooling the product after the reaction is finished, adding chlorosulfonic acid, and preparing the polymeric dispersant after the reaction is finished. The invention also discloses an environment-friendly surface sizing agent. A preparation method of the surface sizing agent includes mixing the polymeric dispersant, acetic acid and water, adding an initiator, reacting the mixture, adding (methyl) styrene and (meth)acrylate type monomers, and sufficiently reacting the mixture to obtain the surface sizing agent. The surface sizing agent is a high-performance environmentally friendly product used for paper surface sizing, is used together with starch for surface sizing of base paper, and can significantly improve water tolerance of paper. The polymeric dispersant has good emulsifying performance so that a synthesized emulsion is low in monomer residue.

The invention provides sizing agent emulsion and a preparation method for the same. The preparation method includes steps of adding fused alkyl ketene dimmers into mixture of cationic polymers and water under the conditions that the temperature ranges from 70 DEG C to 75 DEG C and the stirring speed ranges from 8000rpm/min to 10000rpm/min; stirring; and homogenizing under the condition that the pressure ranges from 10MPa to 25MPa to obtain the sizing agent emulsion. The sizing agent emulsion is a high-performance and environment-friendly product for coatings for papermaking. The product is applied to internal sizing for paper, so that hydrophobicity of the paper can be obviously improved, a Cobb value is reduced, and the surface strength is enhanced.

The invention discloses an internal sizing agent emulsion and a preparation method thereof. The preparation method comprises mixing a cationic polymer and water, adding alkenyl succinic anhydride (ASA) into the mixture, carrying out stirring homogenization and adding aluminum sulfate into the mixture to obtain the internal sizing agent emulsion. The cationic polymer is an aqueous dispersion obtained through copolymerization of a cationic monomer and (methyl) styrene. The preparation method comprises that the mixed monomers undergo a free radical solution polymerization reaction in the presence of 2, 2'-azobis(amidinopropyl)dihydrochloride as an initiator so that a solution is obtained and a surfactant is added into the solution so that a desired cationic polymer is obtained. The internal sizing agent emulsion is high performance and eco-friendly product satisfying papermaking paint use requirements. The internal sizing agent emulsion can be used for paper internal sizing, obviously improve paper hydrophobicity, reduce a Cobb value and improve paper surface strength.

The invention discloses a cationic styrene-acrylic emulsion, and a preparation method and application of the cationic styrene-acrylic emulsion, wherein the preparation method comprises the steps of a) mixing methacrylate, methyl styrene and methacrylic acid to obtain a mixed monomer a; b) mixing an emulsifier, an initiator and water to obtain an emulsifier and initiator aqueous solution b; c) mixing a cationic monomer and water to obtain a cationic monomer aqueous solution c; d) adding the mixed monomer a to the emulsifier, the initiator and water and mixing to obtain a mixed monomer solution d; e) adding the mixed monomer a to the emulsifier, the initiator and water, allowing reaction, and then dropwise adding the mixed monomer solution d, the emulsifier and initiator aqueous solution b and the cationic monomer aqueous solution c, performing reaction; then using alkaline solution to neutralize the mixture till that pH is 7-10, and finally obtaining the product. The invention improves adsorption and retention of the emulsion on the fibers of paper surface, remarkably strengthens surface strength of the paper and notably reduces Cobb value of the coated duplex board with grey back.

The invention discloses a cationic tert-carbonic acid styrene-acrylic emulsion and a preparation method thereof. The preparation method includes the following steps of a) mixing a (meth) acrylate, a (methyl) styrene and a vinyl ester of tertiary carbonic acid to obtain a mixed monomer; b) mixing an emulsifier, an initiator and water to obtain an aqueous solution A; c) mixing a cationic monomer and water to obtain an aqueous solution B; d) mixing the mixed monomer, the emulsifier, the initiator and water to obtain an aqueous solution C; e) adding the mixed monomer into the emulsifier, the initiator and the aqueous solution to be subjected to a reaction and then dropwise adding the aqueous solution C, the aqueous solution A and the aqueous solution B; and f) performing a thermal insulation and neutralizing until the potential of hydrogen (pH) is identical to 6 to 9 to obtain the cationic tert-carbonic acid styrene-acrylic emulsion. According to the cationic tert-carbonic acid styrene-acrylic emulsion and the preparation method thereof, the addition of aluminium sulfate is not required, the surface strength of paper can be remarkably improved, and the Cobb value of a white Manila board can be remarkably decreased.

The invention discloses a high-surface-strength paper surface sizing agent. Modified chitosan is taken as an effective component. The modified chitosan has very well film-forming property, and can beconnected with paper fiber through a hydrogen bond. The paper surface sizing agent is a high-performance and environment-friendly product which can meet using of paper surface sizing. Surface sizing is conducted on a raw paper by the product together with starch, the surface strength can be significantly improved, and the Cobb value of the paper is not lowered. At the same time, the chitosan has the advantages that non-toxicity is achieved, degradation is easy, the biocompatibility is good, film-forming is easy, and antibacterial property is very high.

The invention discloses a preparation method of a water-tolerant paper surface sizing agent. The method comprises intensely mixing a part of high-polymer emulsifier, (methyl) styrene, (methyl) acrylate mixed monomers and deionized water to prepare an emulsion; heating the other part of the high-polymer emulsifier and water inside a container to 80-90 DEG C, then adding in initiator for reaction for 10-20 min, dropwise adding in the prepared emulsion for 1.5-3.0 hr for continuous reaction for 1.0-2.0 hr, and performing cooling and discharging. The invention also relates to the water-tolerant paper surface sizing agent prepared through the method and application of the prepared water-tolerant paper surface sizing agent. According to the preparation method of the water-tolerant paper surfacesizing agent, styrene acrylate emulsion is prepared by polymerizing soap-free emulsion and monomers are dropwise added through monomer emulsification, so that bonding between the styrene acrylate emulsion and the surface of paper can be enhanced. When the water-tolerant paper surface sizing agent is applied to the surface of the paper, the applied paper can have the advantage of high water tolerance; due to the fact that no micromolecular emulsifier is applied during polymerization, the water-tolerant paper surface sizing agent is an environment friendly product.

The invention discloses an internal sizing agent emulsion. A preparation method comprises the steps of mixing cationic polymer with water, adding alkenyl succinic anhydride (ASA), stirring and homogenizing the materials, and adding aluminum sulfate to obtain the internal sizing agent emulsion. The cationic polymer is a aqueous dispersion of a cationic monomer, (methyl)styrene, and silane through copolymerization, the preparation method takes 2,2'-azo-bis (amidino-propyl) dihydrochloride as an initiator, uses the above mixing monomer for free radical solution polymerization to obtain the solution, a surfactant is added, and the cationic polymer is prepared. The internal sizing agent emulsion provided by the invention is high-performance and environment-friendly product capable of being used for the papermaking coating. The product is used for internal sizing of papers, and can obviously improve the hydrophobicity of the papers, reduce the Cobb value and increase the surface strength of the papers.

The invention discloses a surface sizing agent emulsion and a preparation method and an application thereof. The preparation method comprises the following steps: mixing a cationic polymer with water, adding alkenyl succinic anhydride (ASA), stirring and homogenizing, and then adding oxalaldehyde, to obtain the surface sizing agent emulsion; the cationic polymer is prepared by carrying out a reaction of a cationic etherifying agent, chitosan, hydrogen peroxide, silane, acetic acid, sodium hydroxide and a dispersing agent under the action of an initiator. The surface sizing agent emulsion is a high-performance and environmental-protection product which can meet papermaking coatings. The product is applied in paper surface sizing, can significantly improve the hydrophobicity of the paper, reduces Cobb value and improves the paper surface strength.

The invention discloses a starch emulsifier. The starch emulsifier comprises, by weight, 30-40 parts of starch, 30-6 parts of an emulsifier, 0.1-0.4 part of amylase, 1-3 parts of a slow solvent, 0.5-2.0 parts of a catalyst, 4-8 parts of chloroacetic acid, 1-3 parts of a neutralizer and water. A preparation method of the starch emulsifier comprises the following steps: mixing the starch, the emulsifier, amylase and water to obtain starch milk, heating, adding the slow solvent and the catalyst, adding chloroacetic acid, fully reacting, and regulating the pH value of the system by using the neutralizer to obtain the starch emulsifier. The invention also provides an anionic AKD surface sizing agent. The anionic AKD surface sizing agent is prepared by the following steps: mixing the starch emulsifier and water, heating, adding the AKD raw powder under high-speed stirring, adding the obtained mixture into a high-pressure homogenizer, and homogenizing, cooling and discharging the mixture. Theanionic AKD surface sizing agent has excellent compatibility with an anionic auxiliary agent, and can remarkably reduce the water absorption value, improve the surface strength of paper and effectively improves the printability.

The invention provides a water-resistant surface sizing agent. A preparation method of the water-resistant surface sizing agent comprises the following steps: mixing oxidized starch and water, heating, adding caustic soda liquid, adjusting the pH value to 11 or above, continuously heating to 60-80 DEG C, and adding a cross-linking agent for reaction to prepare cross-linked oxidized starch; mixing the cross-linked oxidized starch with water, heating to 80-90 DEG C, and adding an initiator; dropwise adding (methyl) styrene and (methyl) acrylate monomers, reacting, cooling, and discharging to obtain the water-resistant surface sizing agent. A sizing solution obtained by compounding the water-resistant surface sizing agent and gelatinized oxidized starch is used for paper surface sizing, the water resistance of paper can be greatly improved, and the Cobb value of the paper is reduced.

The invention provides modified cationic latex and a preparation method and application thereof. The preparation method includes the following steps: mixing gelatin aqueous solution, emulsifier aqueous solution and initiator aqueous solution, then adding mixed monomers preferably through the manner of dripping for 1-3 hours, thermally insulating for 1-2 hours at 60-95 DEG C, cooling to room temperature, adding borax aqueous solution, and finally filtering. In this way, modified cationic latex can be obtained. According to the invention, the Cobb value can be remarkably reduced, latex can quickly cure almost after leaving the machine, so the gram weight of paper can be reduced; part or even 100% of waste paper is used to replace wood pulp, thus the sizing treatment process is simplified, the cost is reduced and the quality of the product is improved.

The invention discloses an efficient surface sizing agent for paper and a preparation method and application of the efficient surface sizing agent. The surface sizing agent is prepared through two stages of pre-polymerization and polymerization, and the surface sizing agent is prepared from the following polymerization monomers in percentage by weight: 55-75% of a hard monomer, 15-35% of a soft monomer, 5-15% of a cationic monomer, and 2-6% of unsaturated carboxylic acid. The high-potential polymer surface sizing agent has the high cationic property, and thus can be combined with a large number of hydroxyls on the surfaces of fibers, and thus the high-potential polymer surface sizing agent has very good water resistance, film formation and thermoplastic properties. A film layer formed through the efficient surface sizing agent is dense and smooth, on the one hand, the water resistance of the paper can be improved, so that the Cobb value of the paper is decreased, and the anti-damping capability is improved; and on the other hand, good strength performance can be given to the paper. In addition, the smoothness of the paper can further be improved, foam and impurities in the sizing process are reduced, and production stability is improved.