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CN-122011275-A - Papermaking filler wrapping agent and double-aqueous-phase polymerization preparation method thereof

CN122011275ACN 122011275 ACN122011275 ACN 122011275ACN-122011275-A

Abstract

The invention discloses a papermaking filler wrapping agent and a double-aqueous-phase polymerization preparation method thereof, wherein the preparation method of the papermaking filler wrapping agent comprises the following steps of taking acrylamide as a main monomer, mixing a cationic monomer with a hydrophobic side group with rigid benzyl chloride as a phase separation promoting component, mixing functional cations and anionic monomers, polymerizing in a double-aqueous-phase system dissolved with ammonium sulfate, sodium sulfate and polyethylene glycol, keeping the polymerization temperature at 30-60 ℃, and initiating double-aqueous-phase one-step polymerization by adopting a redox initiation system. Compared with the traditional emulsion polymerization, the preparation method of the packing agent does not need organic solvents, emulsifying agents and other harmful substances, and can be prepared by one-step polymerization by taking simple inorganic salts or hydrophilic high molecular substances as phase splitting agents, and has the advantages of simplicity and convenience in preparation, environmental friendliness, strong shearing resistance, high packing retention rate and the like.

Inventors

  • Wen Hankang
  • XU SHENGJIE
  • LI XIANG
  • YAO SHENG
  • LI ENYU
  • QIAN JIN
  • ZHAO KAI
  • CHEN ZHIJIE
  • ZHAO ZHIHAO
  • CHEN YANI

Assignees

  • 浙江传化华洋化工有限公司

Dates

Publication Date
20260512
Application Date
20260209

Claims (10)

  1. 1. The method for preparing the papermaking filler wrapping agent by double aqueous phase polymerization is characterized by comprising the following steps: A. mixing one or more of ammonium sulfate, sodium sulfate and polyethylene glycol with water for dissolution, constructing a double water phase system, dissolving an oxidant in the double water phase system, and regulating the pH to 3.0-5.0; B. mixing a water-soluble acrylamide monomer, a hydrophobic cationic monomer with a rigid benzyl chloride side group, a functional anionic monomer and a functional cationic monomer to prepare a monomer solution, regulating the pH value to 3.0-5.0, heating the aqueous two-phase system in the step A to 30-60 ℃ in a water bath under the condition of antioxidation protection, and simultaneously dropwise adding the monomer solution and a reducing agent into the aqueous two-phase system by adopting a dropwise method to prepare the papermaking filler wrapping agent by one-step polymerization.
  2. 2. The method for preparing a paper filler wrapper by aqueous two-phase polymerization according to claim 1, wherein in the step B, the reaction time of the one-step polymerization is 3 to 5 hours.
  3. 3. The method for preparing the paper-making filler wrapping agent by aqueous two-phase polymerization according to claim 1, wherein the aqueous two-phase system of the step A is prepared by using ammonium sulfate alone or polyethylene glycol alone or a mixture of ammonium sulfate and sodium sulfate, and the mass concentration of the aqueous two-phase system is 15% -25% of the total mass of the aqueous two-phase system.
  4. 4. The method for preparing the papermaking filler wrapping agent by aqueous two-phase polymerization according to claim 1, wherein in the step A, the oxidant is ammonium persulfate or/and sodium bromate accounting for 0.01-0.2% of the total mass of the monomer, and in the step B, the reducing agent is sodium bisulfite or/and sodium metabisulfite accounting for 0.015-0.3% of the total mass of the monomer.
  5. 5. The method for preparing a paper filler wrapping agent by aqueous two-phase polymerization according to claim 1, characterized in that in the step B, the hydrophobic cationic monomer with rigid benzyl chloride side group is selected from one or a mixture of several of methacryloxyethyl dimethyl benzyl ammonium chloride, acryloxyethyl dimethyl benzyl ammonium chloride and vinyl benzyl ammonium chloride, and the molar ratio of the cationic monomer to the acrylamide monomer is (0.1-0.15): 1.
  6. 6. The method for preparing a papermaking filler wrapping agent by aqueous two-phase polymerization according to claim 1, wherein in the step B, the functional cationic monomer is selected from one or a mixture of more than one of dimethylaminoethyl methacrylate, methacryloxyethyl trimethylammonium chloride, dimethylaminoethyl acrylate and acryloxyethyl trimethylammonium chloride, and the molar ratio of the functional cationic monomer to the acrylamide monomer is (0.01-0.05): 1.
  7. 7. The method for preparing a papermaking filler wrapping agent by aqueous two-phase polymerization according to claim 1, characterized in that in the step B, the functional anionic monomer is selected from one or a mixture of several of itaconic acid, acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid, and the molar ratio of the functional anionic monomer to the acrylamide monomer is (0.03-0.06): 1.
  8. 8. The method for preparing a paper filler wrapping agent by double aqueous phase polymerization according to claim 1, wherein the pH value is adjusted by an acid, and the acid is one or a mixture of a plurality of hydrochloric acid, sulfuric acid, phosphoric acid and citric acid.
  9. 9. The method for preparing a papermaking filler wrapping agent by aqueous two-phase polymerization according to claim 1, wherein the polyethylene glycol is selected from one or a mixture of several of polyethylene glycol 6000, polyethylene glycol 8000 and polyethylene glycol 20000.
  10. 10. A papermaking filler wrap prepared by the method of any one of claims 1-9.

Description

Papermaking filler wrapping agent and double-aqueous-phase polymerization preparation method thereof Technical Field The invention belongs to the technical field of papermaking chemicals, and particularly relates to a papermaking filler wrapping agent for improving retention rate of papermaking fillers and a double water phase polymerization preparation method thereof. Background In the paper industry, the addition of fillers like calcium carbonate, kaolin and the like can significantly improve the optical performance and printing adaptability of paper, but the traditional fillers are smaller in size, usually only a few micrometers to tens of hundred nanometers, and the surfaces of the fillers are negatively charged and mutually repel fibers, so that the retention rate is lower. Cationic Polyacrylamide (CPAM) is used as a filler wrapping agent, and is combined with fibers electrostatically through positive charge groups, and meanwhile, hydrophobic chain segments wrap the surfaces of the fillers to form a stable complex, so that the retention rate of the fillers is improved, and the moisture permeation is reduced. The invention patent with publication number CN120625406A discloses a preparation method of a traditional emulsion polymerization CPAM wrapping agent, which is characterized in that acrylamide, hydroxyl acrylate, alkenyl quaternary ammonium salt and alkenyl cationic polyester are reacted to obtain the packing wrapping agent with shearing resistance, paper strength not reduced and high retention rate, but the method is complex in process and is traditional emulsion polymerization, and solvents such as n-heptane and the like exist, so that the environmental problem can be caused. The aqueous two-phase system is polymerized by adopting sulfate phase splitting agents, such as ammonium sulfate, sodium sulfate and the like, and a mild reaction environment is formed through ionic strength adjustment, so that the aqueous two-phase system is low in cost and high in phase separation speed, and the molecular weight uniformity and the functionality of the product can be obviously improved. The traditional double-aqueous-phase polymerization system can not split phases because strong electrostatic repulsion is generated by high-density cationic groups on a polyacrylamide main chain and hydrophobic aggregation of chain segments is inhibited, so that the filler wrapping agent is difficult to prepare. Disclosure of Invention Aiming at the limitations of the prior art, the invention provides a method for preparing a papermaking filler wrapping agent by double-aqueous polymerization, which adopts a double-aqueous polymerization technology, does not need any special use requirement, introduces a rigid benzyl chloride side group cationic monomer to promote phase separation, synthesizes the amphoteric polyacrylamide papermaking filler wrapping agent in one step, simplifies the process, and improves the shearing resistance and the papermaking filler retention rate. The invention adopts the following technical scheme that the method for preparing the papermaking filler wrapping agent by double aqueous phase polymerization specifically comprises the following steps: A. mixing one or more of ammonium sulfate, sodium sulfate and polyethylene glycol with water for dissolution, constructing a double water phase system, dissolving an oxidant in the double water phase system, and regulating the pH to 3.0-5.0; B. mixing a water-soluble acrylamide monomer, a hydrophobic cationic monomer with a rigid benzyl chloride side group, a functional anionic monomer and a functional cationic monomer to prepare a monomer solution, regulating the pH value to 3.0-5.0, heating the aqueous two-phase system in the step A to 30-60 ℃ in a water bath under the condition of antioxidation protection, and simultaneously dropwise adding the monomer solution and a reducing agent into the aqueous two-phase system by adopting a dropwise method to prepare the papermaking filler wrapping agent by one-step polymerization. The invention innovatively introduces the rigid benzyl chloride side group cationic monomer, the aromatic ring structure provides obvious hydrophobicity and space rigidity, the segment solvation capacity is reduced, meanwhile, the chlorine atoms enhance intermolecular van der Waals effect, the homogeneous phase stable state is synergistically broken, and a stable polymer enrichment phase is induced to be formed. The structure realizes the dynamic balance of electrostatic repulsion and hydrophobic driving, and the split-phase switching effect is activated in a high-cation system for the first time, so that the direct preparation of the high-molecular-weight and low-viscosity papermaking filler wrapping agent by one-step double-aqueous-phase polymerization becomes possible, and the limitation of the existing filler wrapping agent is effectively overcome. Therefore, the invention adopts a double water phase polymerization technology, does not n