CN117924623A - Modified styrene-butadiene copolymer composite latex for paper coating - Google Patents

Modified styrene-butadiene copolymer composite latex for paper coating Download PDF

Info

Publication number
CN117924623A
CN117924623A CN202410144767.5A CN202410144767A CN117924623A CN 117924623 A CN117924623 A CN 117924623A CN 202410144767 A CN202410144767 A CN 202410144767A CN 117924623 A CN117924623 A CN 117924623A
Authority
CN
China
Prior art keywords
hectorite
latex
butadiene copolymer
modified styrene
paper coating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202410144767.5A
Other languages
Chinese (zh)
Inventor
张连腾
米普科
郑作宪
赵建斌
杨涛
张志高
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Guangdong Chengming Chemicals Co ltd
Guangxi Tenglong Chemical Technology Co ltd
East China University of Science and Technology
Original Assignee
Guangdong Chengming Chemicals Co ltd
Guangxi Tenglong Chemical Technology Co ltd
East China University of Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Guangdong Chengming Chemicals Co ltd, Guangxi Tenglong Chemical Technology Co ltd, East China University of Science and Technology filed Critical Guangdong Chengming Chemicals Co ltd
Priority to CN202410144767.5A priority Critical patent/CN117924623A/en
Publication of CN117924623A publication Critical patent/CN117924623A/en
Pending legal-status Critical Current

Links

Landscapes

  • Paper (AREA)

Abstract

The invention relates to modified styrene-butadiene copolymer composite latex for paper coating, which comprises the following components in percentage by weight: 36 to 46 percent of aliphatic conjugated diene monomer of C 4~C5; 50-60% of vinyl unsaturated monomer; 2.0 to 5.0 percent of acidified hectorite sol; 2.5 to 5.0 percent of unsaturated carboxylic acid monomer; 1.0 to 3.0 percent of unsaturated amide monomer; the acidified hectorite sol consists of laponite, a dispersing agent and an acidifying agent, and the acidified hectorite sol is prepared from laponite through two steps of dispersing, dissolving and acidifying. According to the invention, after the hectorite is stably dispersed and pre-polymerized and coated by the dispersing agent, the styrene-butadiene copolymerization is carried out, so that the defects of the prior art are overcome, and the defects of unstable polymerization products, poor bonding performance, poor stability and the like are overcome.

Description

Modified styrene-butadiene copolymer composite latex for paper coating
[ Field of technology ]
The invention relates to the technical field of styrene-butadiene latex, in particular to modified styrene-butadiene copolymer composite latex for paper coating.
[ Background Art ]
With the development of scientific technology and the continuous improvement of the living standard of people, the demand of high-grade paper coated paper and coated board paper is rapidly increased, and non-woven fabrics and chemical fiber products are used in a large quantity, so that the demand of styrene-butadiene latex for paper coating, non-woven fabrics/paperboards and carpet backing is continuously increased, and the most important application market of the styrene-butadiene latex is enlarged.
Styrene-butadiene latex is an emulsion polymer containing monomers such as styrene, butadiene, acrylic acid, etc., and water by the action of an initiator, an emulsifier, etc. The styrene-butadiene latex is generally synthesized by emulsion polymerization techniques at a high temperature of 65-95 ℃ and a pressure of about 1bar to 6 bar. In paper and paperboard coatings, styrene-butadiene latex has many uses, such as coating binders in paper coating. The styrene-butadiene latex enhances the binding force of the pigment, so that the paper is smoother, harder and waterproof, and the price of the styrene-butadiene latex is competitive with other types of adhesives. It is the first polymer coating for paper due to its ability to bind pigment and filler and its strength.
The styrene-butadiene latex has excellent film forming property and adhesiveness as water-based polymer emulsion, is low in cost, safe and environment-friendly, and becomes a film forming substance which is most widely applied in papermaking and chemical fiber materials. However, in many applications, especially in paper coating, it is often difficult to combine the adhesive strength and the glossiness of the coated paper product to make both excellent levels, and at the same time, the coating technology and the printing technology are high-speed, so that a higher stability requirement is put on the coated latex, and the problem of stability of the latex coating on a high-speed paper machine can be solved by adopting a high-efficiency emulsifier or increasing the using amount of the emulsifier, and the printing performance and the water resistance of the paper are inevitably greatly reduced. To solve these problems, functionalization of the coating latex has become an important method for improving the application performance of the coating latex, and an effective method is to carry out composite modification on the styrene-butadiene latex. Among the numerous composite modification methods thereof, the composite material of the inorganic nanomaterial modified styrene-butadiene latex is one direction of the research of the modified styrene-butadiene latex.
In the traditional emulsion polymerization, an emulsifier is added to stabilize and nucleate the system, but the emulsifier in the product can have certain influence on the adhesive property, optical property, surface property, water resistance and the like of the emulsion polymer. More importantly, the emulsifier is usually expensive, the addition of the emulsifier increases the cost of the product, and the surfactant is easy to enrich and migrate to the film-air and the film-substrate in the emulsion film forming process, so that the water resistance, the adhesive force and the bonding strength of the film are reduced. To solve the problem of emulsifiers, soap-free or low-soap emulsion polymerization processes using no or little emulsifier have been developed successively, but the stability of the emulsion is poor because of the absence or lack of protection of the emulsifier in the soap-free or low-soap emulsion polymerization system, which makes it difficult to meet the requirements of paper coating. There is therefore a need to find suitable emulsion polymerization processes and techniques, to develop environmentally friendly and excellent aqueous polymer materials, to promote the upgrading of polymer materials and to industrial applications in paper coating.
Modified butadiene-styrene copolymer latices are numerous, including the addition of organoclay as a filler to form styrene-butadiene hybrid polymers or nanocomposites, and core-shell or multiphase structured butadiene-styrene copolymer latices, such as those of chinese patent 201910648550.7, 201910648556.4, 201910648658.6, 201910648534.8, etc. These modifications provide the requisite and ever-expanding market for synthetic latexes and improve the final product properties. In recent years, solid particle stabilized emulsions, i.e., PICKERI NG emulsions, have been developed rapidly and have attracted considerable attention in recent years because they avoid the toxicity and negative effects of surfactants (e.g., foaming, toxicity, material properties) and the unique self-assembly effects of interfacial particles.
The patent CN201711167541.3 prepares the aqueous acrylic resin/hectorite organic-inorganic composite leather finishing agent, which is characterized in that nano-particle hectorite is used as a stabilizer to replace the traditional organic surfactant, and the emulsion polymerization technology is adopted to prepare the aqueous acrylic resin/hectorite composite leather finishing agent which takes acrylate polymer as a core and inorganic nano-particles as a shell, thereby not only avoiding the use of the organic surfactant in the traditional emulsion polymerization method and solving the problem of toxicity of the organic emulsifier and the negative influence on the film forming performance in the later period of emulsion, but also the used stabilizer hectorite nano-particles are nano-clay with a lamellar structure, can be used as a reinforcing modifier of acrylic resin, and remarkably improve the mechanical property, wear resistance and thermal stability of the finishing agent and endow a coating film with good ultraviolet aging resistance. However, the bentonite has hydrophilicity, which is difficult to disperse in a polymer matrix, and the hydrophilic property of the bentonite needs to be changed through special treatment so as to be compatible with the polymer matrix, and the bentonite can only exert the due modification property when being dispersed into the polymer matrix, and the modification method is not disclosed in the method, and the key properties such as mechanical stability, chemical stability, storage stability and the like of the composite emulsion taking the nano-particle bentonite as the stabilizer are not examined. It has been noted that laponite is a highly hydrophilic synthetic layered silicate having a nano platelet structure, which has a particle diameter concentrated in 25 to 50nm, a platelet thickness of-1 n m, a controllable size and a high hydrophilicity, and can be exfoliated into a platelet structure in water to finally form a colorless transparent colloidal dispersion, and thus has been widely used as an additive and rheological agent in industrial and consumer products such as paints, varnishes, printing, toothpastes, and its colloidal characteristics make it exhibit unique advantages in stabilizing emulsion or emulsion particles. In fact, some researches have reported that the nanoclay-modified styrene-butadiene polymer, such as patent CN200810200760.1, is modified with sodium bentonite-modified styrene-butadiene latex, which is prepared by mixing sodium bentonite and styrene-butadiene latex in a mechanical blending manner at a mixing ratio of 10%, and the obtained bentonite-modified styrene-butadiene latex improves the adhesive property of the latex. However, the inorganic nanoclay has a problem of poor compatibility with organic polymers, and the patent does not examine key properties such as mechanical stability, chemical stability, storage stability, and the like of the obtained composite emulsion. The present inventors have found that the polymerization process can solve this problem well, and that the solid particle emulsifier for stabilizing the emulsion has the advantages of low cost, no toxicity, no pollution, etc., and the prepared polymer emulsion does not need to undergo complicated post-treatment.
Inorganic nanomaterial clays are often used to prepare inorganic/polymeric nanomaterial composites. In order to produce a good nanocomposite, the clay should be treated before being used in the polymer. Due to the hydrophilic nature of clay, it is difficult to disperse in a polymer matrix. To modify the compatibility of the clay with the polymer host, the clay is dispersed in the polymer matrix; furthermore, the clay layer contains cations, and the styrene-butadiene latex is an anionic polymer, so that the direct mixing of the two polymers can influence the stability of the styrene-butadiene latex. For this reason, the modification of clay should break the aggregation structure of clay first, usually needs to reduce the cations on the clay layer surface by cation exchange technology to make it more organophilic; alkyl phosphorus and imidazole surfactants are commonly used as clay modifying treatments to prepare nanocomposite materials.
Based on the above technical conditions, the present inventors have proposed the following technical solutions.
[ Invention ]
The invention aims to solve the technical problem of overcoming the defects in the prior art and providing the modified styrene-butadiene copolymer composite latex for paper coating.
In order to solve the technical problems, the invention adopts the following technical scheme that the modified styrene-butadiene copolymer composite latex for paper coating comprises the following components in percentage by weight: 36 to 46 percent of aliphatic conjugated diene monomer of C 4~C5; 50-60% of vinyl unsaturated monomer; 2.0 to 5.0 percent of acidified hectorite sol; 2.5 to 5.0 percent of unsaturated carboxylic acid monomer; 1.0 to 3.0 percent of unsaturated amide monomer; the acidified hectorite sol is prepared from laponite, a dispersing agent and an acidifying reagent, wherein the laponite sol is prepared from laponite through two steps of dispersing, dissolving and acidifying, the dispersing agent is DISPER BYK-163 and alkyl polyoxyethylene ether, and the acidifying reagent is glacial acetic acid.
Further, in the above technical scheme, the aliphatic conjugated diene monomer of C 4~C5 is selected from 1, 3-butadiene or a mixture of 1, 3-butadiene and isoprene.
Further, in the above technical scheme, the ethylenically unsaturated monomer is selected from styrene, or a mixture of styrene, methyl methacrylate and acrylonitrile.
Further, in the above technical scheme, the unsaturated carboxylic acid is selected from one or a mixture of acrylic acid, methacrylic acid, itaconic acid and fumaric acid.
In the above technical scheme, the unsaturated amide is one selected from acrylamide, methacrylamide, N-dimethylacrylamide and methylol acrylamide.
Furthermore, in the technical scheme, the preparation method comprises the following steps: (1) preparation of hectorite sol: adding 280 g of deionized water into a 0.5 liter reactor with stirring, heating to 80 ℃, slowly adding 20g of nano hectorite, 0.2-1 g DISPER BYK-163 and 0.2-1 g of alkyl polyoxyethylene ether, stirring and dispersing for 2 hours, then slowly adding glacial acetic acid under stirring, and regulating the pH of the solution to 3.5-4.0 to obtain a hectorite sol with 6.5% of solid content;
(2) Prepolymerization: 130-300 g of the acidified hectorite sol, 6-16 g of unsaturated carboxylic acid, 0.04 g of chelating agent, 0.12 g of electrolyte, 0.4 g of molecular weight regulator and deionized water are added into a1 liter high-pressure reaction kettle, nitrogen replacement, high-speed stirring and heating to 80 ℃ are carried out, a pre-prepared initiator solution is added, and the reaction is started for 30 minutes;
(3) Continuous polymerization: after the reaction is carried out for 30 minutes, 0 to 4g of unsaturated carboxylic acid, 4 to 12 g of 50 percent unsaturated amide monomer aqueous solution, 8 to 12 g of 30 percent emulsifier aqueous solution, 4 hours, 3 to 4.5 g of molecular weight regulator, 144 to 184 g of mixed solution of aliphatic conjugated diene monomer of C 4~C5 and 200 to 240 g of vinyl unsaturated monomer, 12 to 26 g of 20 percent initiator solution, 5 hours, and heat preservation at 85 ℃ for 2 hours after the complete dropwise addition;
(4) Post-treatment:
Slowly adding alkali into the latex to adjust the pH value to 5.0, respectively dripping 4-6 g of 20% tertiary butyl hydroperoxide aqueous solution and 3-6 g of 20% diabolo aqueous solution, reacting for 4 hours, cooling and discharging, and adjusting the pH value to 6.0-7.0 to obtain the hectorite composite modified styrene-butadiene copolymer latex.
Furthermore, in the technical scheme, the dispersing agent is DISPER BYK-163 and alkyl polyoxyethylene ether, the dosage of DISPER BYK-163 is 5-15% of the weight of the dry weight of the hectorite, and the dosage of the alkyl polyoxyethylene ether is 5-15% of the weight of the dry weight of the hectorite; the DISPER BYK-163 dispersing agent is a dispersing agent of the German Pick chemical company, and the composition of the dispersing agent is macromolecule acrylic acid segmented copolymer resin; the alkyl polyoxyethylene ether is C 12~C16 alkyl polyoxyethylene ether, the EO value of the alkyl polyoxyethylene ether is 10, and the alkyl polyoxyethylene ether can be used for preparing a product with good chemical stability.
Further, in the above technical solution, the emulsifier is sodium dodecyl benzene sulfonate, the chelating agent is sodium ethylenediamine tetraacetate, abbreviated EDTA; the electrolyte is potassium phosphate, and the molecular weight regulator is C 8~C12 alkyl mercaptan, in particular tertiary-dodecyl mercaptan, n-dodecyl mercaptan or a mixture thereof; the initiator is ammonium persulfate.
Furthermore, in the above technical scheme, the modified styrene-butadiene copolymer latex is used as adhesion in the field of paper coating.
In addition, the tertiary butyl hydroperoxide and diabolos described in the work-up stage are redox initiators, useful redox initiators being, for example, persulfates and sodium bisulfites, persulfates and mercaptans, persulfates and diabolos (sodium formaldehyde sulfoxylate); preferably, the mass ratio of the tert-butyl hydroperoxide to the diabolo is 1:0.5 to 1:1.0, t-butyl hydroperoxide was used in an amount of 50% of the total weight of residual monomers. And slowly adding alkali into the latex obtained in the post-treatment stage for neutralization, and filtering to obtain the finished latex. The final copolymer composite latex has 49-51% of solid content, pH of 6.0-7.0, viscosity of 100-200 mPa.S, surface tension of 36-46 mN/m, particle size of 145-165 nm and gel content of 76-85%.
According to the invention, after the hectorite is stably dispersed and pre-polymerized and coated by the dispersing agent, the styrene-butadiene copolymerization is carried out, so that the defects of the prior art are overcome, and the defects of unstable polymerization products, poor bonding performance, poor stability and the like are overcome. According to the invention, clay hectorite is used as one of emulsion polymerization components and added into a polymerization system, low-dimensional nano-particle hectorite with a lamellar structure is introduced into styrene-butadiene copolymer latex through an emulsion polymerization technology, and hectorite particles form protective layer stable emulsion on the peripheral surface of latex particles, so that the core-shell structure water-based inorganic-styrene-butadiene copolymer material is formed.
The preparation process of the modified copolymer composite latex is simple, the reaction process is stable, the reaction time is short, and the polymerization conversion rate is high; the reaction process does not need a low-temperature refrigerant and a complex monomer recovery and degassing process; the complex of hectorite in the polymerized composition improves the physical and optical properties of the product, has high latex napping strength, good luster, excellent water resistance, excellent high-speed mechanical stability, chemical stability and storage stability of emulsion paint, and no coagulum in storage for 180 days at 10-35 ℃.
[ Detailed description ] of the invention
The invention is further illustrated below with reference to specific examples. The total monomer addition in the examples and comparative examples was in wt% (weight percent).
Emulsion polymerization was carried out in a stainless steel reactor, which was replaced with nitrogen and equipped with a stirrer and temperature was adjusted.
Example 1
Adding 280 g of deionized water into a 0.5 liter reactor with stirring, slowly adding 20 g of nano hectorite, 0.5 g of DISPER BYK-163 dispersing agent and 0.4 g of alkyl polyoxyethylene ether when heating to 80 ℃, stirring and dispersing for 2 hours, and uniformly dissolving to obtain hectorite sol; then 2.55 g of glacial acetic acid is slowly added under stirring, and the pH value of the solution is adjusted to 4.0, so as to obtain the acidified hectorite sol.
240 G of the acidified hectorite sol, 10 g of itaconic acid, 0.04 g of EDTA chelating agent, 0.13 g of dodecyl mercaptan molecular weight regulator and 93 g of water are added into a1 liter high-pressure reaction kettle, nitrogen substitution is performed, high-speed stirring is performed, 3.5 g of a pre-prepared 20% ammonium persulfate initiator solution is added after the temperature is raised to 80 ℃, and the reaction is started for 30 minutes.
After the reaction was carried out for 30 minutes, 4 g of acrylic acid was added dropwise to each of the mixture for 4 hours, 10 g of a 50% aqueous acrylamide monomer solution for 4 hours, 10 g of a 30% aqueous sodium dodecylbenzenesulfonate solution for 4 hours, a mixture of 3.5 g of n-dodecylmercaptan molecular weight modifier, 160 g of butadiene, 182 g of styrene and 30 g of methyl methacrylate monomer for 4 hours, 26 g of a 20% ammonium persulfate solution for 5 hours, and the mixture was kept at 85℃for 2 hours after the completion of all dropwise addition.
And slowly adding alkali into the latex to adjust the pH to 5.0, respectively dropwise adding 5g of tert-butyl hydroperoxide with 20% and a redox initiation system composed of 20% of diabolos to react for 4 hours, cooling and discharging, and adjusting the pH to 6.3 to obtain the modified styrene-butadiene copolymer composite latex with a core-shell structure for paper coating.
Example 2
Adding 280 g of deionized water into a 0.5 liter reactor with stirring, slowly adding 20 g of nano hectorite, 0.2 g of DISPER BYK-163 dispersing agent and 1.0 g of alkyl polyoxyethylene ether when heating to 80 ℃, stirring and dispersing for 2 hours, and uniformly dissolving to obtain hectorite sol; then 2.6 g of glacial acetic acid is slowly added under stirring, and the pH value of the solution is regulated to 3.9, so as to obtain the acidified hectorite sol.
300 G of the acidified hectorite sol, 10 g of methacrylic acid, 0.04 g of EDTA chelating agent, 0.135 g of dodecyl mercaptan molecular weight regulator and 74 g of deionized water are added into a 1-liter high-pressure reaction kettle, nitrogen substitution, high-speed stirring and heating to 80 ℃ are carried out, 4.5 g of a pre-prepared 20% ammonium persulfate initiator solution is added, the reaction timing is started, and the reaction is finished for 30 minutes.
After the reaction was carried out for 30 minutes, 10g of acrylic acid was added dropwise to each of the mixture for 4 hours, 6g of a 50% aqueous solution of methylolacrylamide monomer for 4 hours, 10g of a 30% aqueous solution of sodium dodecylbenzenesulfonate emulsifier for 3 hours, 3.8 g of a mixed solution of a tertiary dodecylmercaptan molecular weight regulator, 186 g of butadiene monomer and 192 g of styrene monomer for 4 hours, 140 g of a 20% aqueous solution of ammonium persulfate for 5 hours, and the mixture was kept at 85℃for 2 hours after the completion of all dropwise addition.
After the pH of the latex is slowly adjusted to 5.0 by adding alkali, respectively dropwise adding 4.0 g of tert-butyl hydroperoxide with 20% and a redox initiation system composed of 3.5 g of 20% of diabolo to react for 4 hours, cooling and discharging, and adjusting the pH to 6.5 to obtain the modified styrene-butadiene copolymer composite latex for coating paper with a core-shell structure.
Example 3
Adding 280 g of deionized water into a 0.5 liter reactor with stirring, slowly adding 20 g of nano hectorite, 0.8 g of DISPER BYK-163 dispersing agent and 0.4 g of alkyl polyoxyethylene ether when heating to 80 ℃, stirring and dispersing for 2 hours, and uniformly dissolving to obtain hectorite sol; then slowly adding 3.05 g of glacial acetic acid under the stirring condition, and regulating the pH value of the solution to 3.6 to obtain acidified hectorite sol;
200 g of the acidified hectorite sol, 12 g of methacrylic acid, 0.04 g of EDTA chelating agent, 0.135 g of dodecyl mercaptan molecular weight regulator and 133 g of water are added into a 1-liter high-pressure reaction kettle, nitrogen substitution, high-speed stirring and heating to 80 ℃,3 g of a pre-prepared 20% ammonium persulfate initiator solution are added, and the reaction is started for 30 minutes after the reaction is started.
After the reaction was carried out for 30 minutes, 6 g of acrylic acid was added dropwise to each of the mixture for 4 hours, 15 g of a 50% aqueous solution of methacrylamide monomer for 4 hours, 11 g of a 30% aqueous solution of sodium dodecylbenzenesulfonate for 4 hours, a mixture of 3.6 g of n-dodecylmercaptan molecular weight regulator, 150 g of butadiene, 160 g of styrene and 28.5 g of acrylonitrile monomer for 4 hours, 26 g of a 20% aqueous solution of ammonium persulfate for 5 hours, and the mixture was kept at 85℃for 2 hours after the completion of all dropwise addition.
And slowly adding alkali into the latex to adjust the pH to 5.0, respectively dropwise adding a redox initiation system consisting of 5.5 g of 20% tertiary butyl hydroperoxide aqueous solution and 5g of 20% diabolo aqueous solution, reacting for 4 hours, cooling and discharging, and adjusting the pH to 6.5 to obtain the modified styrene-butadiene copolymer composite latex for coating the paper with the core-shell structure.
Example 4
Adding 280 g of deionized water into a 0.5 liter reactor with stirring, slowly adding 20 g of nano hectorite, 1.0 g of DISPER BYK-163 dispersing agent and 0.35 g of alkyl polyoxyethylene ether when heating to 80 ℃, stirring and dispersing for 2 hours, and uniformly dissolving to obtain hectorite sol; then slowly adding 2.70 g of glacial acetic acid under the stirring condition, and regulating the pH value of the solution to 3.8 to obtain acidified hectorite sol;
250 g of the acidified hectorite sol, 12 g of fumaric acid, 0.04 g of EDTA chelating agent, 0.15 g of dodecyl mercaptan molecular weight regulator and 140 g of deionized water are added into a 1-liter high-pressure reaction kettle, nitrogen substitution is performed, high-speed stirring is performed, after the temperature is raised to 80 ℃, 5 g of a pre-prepared 20% ammonium persulfate initiator solution is added, and the reaction is started for 30 minutes.
After the reaction was carried out for 30 minutes, 8 g of methacrylic acid was added dropwise to each of the mixture for 4 hours, 24 g of a 50% aqueous acrylamide monomer solution for 4 hours, 12 g of a 30% aqueous sodium dodecylbenzenesulfonate solution for 4 hours, 3.5 g of a tertiary dodecyl mercaptan molecular weight modifier, 144 g of butadiene, 40 g of isoprene monomer, 171 g of styrene and 25 g of methyl methacrylate, and 12 g of a 20% ammonium persulfate solution for 5 hours were added dropwise thereto, and the mixture was kept at 85℃for 2 hours after completion of all dropwise addition.
After the pH of the latex is slowly adjusted to 5.0 by adding alkali, respectively dropwise adding 4g of tert-butyl hydroperoxide with 20% and a redox initiation system composed of 5 g of diabolos with 20% to react for 4 hours, cooling and discharging, and adjusting the pH to 6.6 to obtain the modified styrene-butadiene copolymer composite latex with a core-shell structure for paper coating.
Example 5
Adding 280 g of deionized water into a 0.5 liter reactor with stirring, slowly adding 20 g of nano hectorite, 0.4 g of DISPER BYK-163 dispersing agent and 0.6 g of alkyl polyoxyethylene ether when heating to 80 ℃, stirring and dispersing for 2 hours, and uniformly dissolving to obtain hectorite sol; then adding 2.75 g of glacial acetic acid slowly under the stirring condition, and regulating the pH value of the solution to 3.8 to obtain acidified hectorite sol;
185 g of the acidified hectorite sol, 15 g of methacrylic acid, 0.04 g of EDTA chelating agent, 0.135 g of dodecyl mercaptan molecular weight regulator and 140 g of water are added into a1 liter high-pressure reaction kettle, nitrogen substitution, high-speed stirring and heating to 80 ℃ are carried out, 6g of a pre-prepared 20% ammonium persulfate initiator solution is added, and the reaction is started for 30 minutes after timing.
After the reaction was carried out for 30 minutes, 5g of acrylic acid was added dropwise, respectively, for 4 hours, 6g of a 50% aqueous solution of N, N-dimethylacrylamide, for 4 hours, 8g of a 30% aqueous solution of dodecyldiphenylether disulfonate, and a mixed solution of 3.95 g of a tertiary dodecylmercaptan molecular weight regulator, 176 g of butadiene, 8g of acrylonitrile monomer, 173 g of styrene, 25 g of methyl methacrylate, for 4 hours, 26 g of a 20% aqueous solution of ammonium persulfate, and after completion of all the dropwise addition, the mixture was kept at 85℃for 2 hours.
And (3) slowly adding alkali into the latex to adjust the pH to 5.0, respectively dropwise adding 6 g of tert-butyl hydroperoxide with 20% and 5 g of redox initiation system composed of 20% diabolos to react for 4 hours, cooling and discharging, and adjusting the pH to 6.5 to obtain the modified styrene-butadiene copolymer composite latex for coating paper with a core-shell structure.
Example 6
Adding 280 g of deionized water into a 0.5 liter reactor with stirring, slowly adding 20 g of nano hectorite, 0.5 g of DISPER BYK-163 dispersing agent and 0.6 g of alkyl polyoxyethylene ether when heating to 80 ℃, stirring and dispersing for 2 hours, and uniformly dissolving to obtain hectorite sol; then 2.75 g of glacial acetic acid is slowly added under stirring, and the pH value of the solution is adjusted to 3.7, so as to obtain the acidified hectorite sol.
225 G of the acidified hectorite sol, 8g of fumaric acid, 0.04 g of EDTA chelating agent, 0.135 g of dodecyl mercaptan molecular weight regulator and 118 g of water are added into a 1-liter high-pressure reaction kettle, nitrogen substitution is performed, high-speed stirring is performed, after the temperature is raised to 80 ℃, 4.5 g of a pre-prepared 20% ammonium persulfate initiator solution is added, the reaction is started, and the reaction is completed for 30 minutes.
After the reaction was carried out for 30 minutes, 20g of a 50% aqueous solution of methylolacrylamide monomer, 10 g of a 30% aqueous solution of dodecyldiphenyloxide disulfonate emulsifier, 3 hours, 3.3 g of a mixed solution of a tertiary dodecyl mercaptan molecular weight regulator, 144 g of butadiene monomer, 200 g of styrene monomer and 38 g of acrylonitrile were each added dropwise for 4 hours, 16 g of a 20% aqueous solution of ammonium persulfate for 5 hours, and the mixture was kept at 85℃for 2 hours after the completion of all the dropwise addition.
And slowly adding alkali into the latex to adjust the pH to 5.0, respectively dropwise adding a redox initiation system consisting of 4 g of 20% tertiary butyl hydroperoxide aqueous solution and 3.5 g of 20% diabolo aqueous solution, reacting for 4 hours, cooling and discharging, and adjusting the pH to 6.3 to obtain the modified styrene-butadiene copolymer composite latex for coating the paper with the core-shell structure.
Comparative example 1
Example 1 was repeated except that no dispersant DISPER BYK-163 was used in the preparation of the acidified laponite sol.
Comparative example 2
Example 1 was repeated except that no glacial acetic acid was used in the preparation of the acidified laponite sol.
Comparative example 3
Example 1 was repeated except that the laponite sol was not acidified during the prepolymerization.
The latices obtained in examples 1 to 6 and comparative examples 1 to 3 were formulated into paper coating paints for light paper coating, and the properties of the latices and paints and coated papers are shown in Table 1.
As can be seen from Table 1, examples 1 to 7 all have better stability properties (the lower the number, the better the stability, the more 0.03% or less of the mechanical stability is acceptable, the less 0.03% or less of the chemical stability is acceptable, and the less 0.02% or less of the storage stability is acceptable) than comparative examples 1 to 3.
TABLE 1
The foregoing is merely illustrative of the technical solution of the embodiments of the present invention, and is not meant to be limiting, and those skilled in the art will understand that the technical solution of the embodiments of the present invention may be modified or equivalently replaced, and that the modified or equivalent replacement does not deviate from the scope of the technical solution of the embodiments of the present invention.

Claims (9)

1. The modified styrene-butadiene copolymer composite latex for paper coating is characterized by comprising the following components in percentage by weight:
The acidified hectorite sol is prepared from laponite, a dispersing agent and an acidifying reagent, wherein the laponite sol is prepared from laponite through two steps of dispersing, dissolving and acidifying, the dispersing agent is DISPER BYK-163 and alkyl polyoxyethylene ether, and the acidifying reagent is glacial acetic acid.
2. The modified styrene-butadiene copolymer composite latex for paper coating of claim 1, wherein the aliphatic conjugated diene monomer of C 4~C5 is selected from 1, 3-butadiene or a mixture of 1, 3-butadiene and isoprene.
3. The modified styrene-butadiene copolymer composite latex for paper coating of claim 1, wherein the ethylenically unsaturated monomer is selected from the group consisting of styrene, or a mixture of styrene with methyl methacrylate, acrylonitrile.
4. The modified styrene-butadiene copolymer composite latex for paper coating of claim 1, wherein the unsaturated carboxylic acid is one or a mixture of acrylic acid, methacrylic acid, itaconic acid, fumaric acid.
5. The modified styrene-butadiene copolymer composite latex for paper coating of claim 1, wherein the unsaturated amide is one selected from the group consisting of acrylamide, methacrylamide, N-dimethylacrylamide, and methylolacrylamide.
6. The modified styrene-butadiene copolymer composite latex for paper coating according to any one of claims 1 to 5, wherein the preparation method comprises the steps of:
(1) Preparing hectorite sol: adding 280 g of deionized water into a 0.5 liter reactor with stirring, heating to 80 ℃, slowly adding 20 g of nano hectorite, 0.2-1 g DISPER BYK-163 and 0.2-1 g of alkyl polyoxyethylene ether, stirring and dispersing for 2 hours, then slowly adding glacial acetic acid under stirring, and regulating the pH of the solution to 3.5-4.0 to obtain a hectorite sol with 6.5% of solid content;
(2) Prepolymerization: 130-300 g of the acidified hectorite sol, 6-16 g of unsaturated carboxylic acid, 0.04 g of chelating agent, 0.12 g of electrolyte, 0.4 g of molecular weight regulator and deionized water are added into a1 liter high-pressure reaction kettle, nitrogen replacement, high-speed stirring and heating to 80 ℃ are carried out, a pre-prepared initiator solution is added, and the reaction is started for 30 minutes;
(3) Continuous polymerization: after the reaction is carried out for 30 minutes, 0 to 4g of unsaturated carboxylic acid, 4 to 12 g of 50 percent unsaturated amide monomer aqueous solution, 8 to 12 g of 30 percent emulsifier aqueous solution, 4 hours, 3 to 4.5 g of molecular weight regulator, 144 to 184 g of mixed solution of aliphatic conjugated diene monomer of C 4~C5 and 200 to 240 g of vinyl unsaturated monomer, 12 to 26 g of 20 percent initiator solution, 5 hours, and heat preservation at 85 ℃ for 2 hours after the complete dropwise addition;
(4) Post-treatment:
slowly adding alkali into the latex to adjust the pH value to 5.0, respectively dripping 4-6 g of 20% tertiary butyl hydroperoxide aqueous solution and 3-6 g of 20% diabolo aqueous solution, reacting for 4 hours, cooling and discharging, and adjusting p H to 6.0-7.0 to obtain the hectorite composite modified styrene-butadiene copolymer latex.
7. The modified styrene-butadiene copolymer composite latex for paper coating of claim 6, wherein the dispersant is DISPER BYK-163 and alkyl polyoxyethylene ether, the amount of DISPER BYK-163 is 5-15% of the weight of the dry weight of the hectorite, and the amount of alkyl polyoxyethylene ether is 5-15% of the weight of the dry weight of the hectorite; the DISPER BYK-163 dispersing agent comprises macromolecular acrylic block copolymer resin; the alkyl polyoxyethylene ether is C 12~C16 alkyl polyoxyethylene ether.
8. The modified styrene-butadiene copolymer composite latex for paper coating of claim 6, wherein the emulsifier is sodium dodecylbenzenesulfonate, the chelating agent is sodium ethylenediamine tetraacetate, the electrolyte is potassium phosphate, the molecular weight regulator is C 8~C12 alkyl mercaptan, and the initiator is ammonium persulfate.
9. The modified styrene-butadiene copolymer composite latex for paper coating of claim 6, wherein said modified styrene-butadiene copolymer latex is used as an adhesive in the paper coating field.
CN202410144767.5A 2024-02-01 2024-02-01 Modified styrene-butadiene copolymer composite latex for paper coating Pending CN117924623A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202410144767.5A CN117924623A (en) 2024-02-01 2024-02-01 Modified styrene-butadiene copolymer composite latex for paper coating

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202410144767.5A CN117924623A (en) 2024-02-01 2024-02-01 Modified styrene-butadiene copolymer composite latex for paper coating

Publications (1)

Publication Number Publication Date
CN117924623A true CN117924623A (en) 2024-04-26

Family

ID=90759427

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202410144767.5A Pending CN117924623A (en) 2024-02-01 2024-02-01 Modified styrene-butadiene copolymer composite latex for paper coating

Country Status (1)

Country Link
CN (1) CN117924623A (en)

Similar Documents

Publication Publication Date Title
KR20030040476A (en) High acid aqueous nanocomposite dispersions
CN105778002A (en) Method of preparing carboxyl styrene butadiene rubber through emulsion polymerization
EP2438097B1 (en) Fine-particle, cationic, aqueous polymer dispersions, method for the production thereof, and use thereof
KR20010024779A (en) Coating composition
CN110483676A (en) A kind of butadiene-styrene copolymer latex of heterogeneous structure and its preparation method and application
US4544697A (en) Amphoteric latexes containing pH independent and pH dependent bound charges
KR101394405B1 (en) Styrene-Butadiene latex for coating paper and its preparing method
US4582663A (en) Amphoteric latexes containing pH independent and pH dependent bound charges
DE60028694T2 (en) emulsion polymers
CN117924623A (en) Modified styrene-butadiene copolymer composite latex for paper coating
JP3201669B2 (en) Composition for paper coating
KR101345217B1 (en) Novel hydrophilic chain transfer agent and end-modified styrene-butadiene copolymer using them
KR102210031B1 (en) Matrix copolymer, graft copolymer, and thermoplastic resin composition
CN117924622A (en) Modified styrene-butadiene latex
JP4125078B2 (en) Method for producing copolymer latex for paper coating
CN117986497A (en) Modified styrene-butadiene latex for paper coating
CN117986498A (en) Butyl benzene copolymer composite latex and preparation method and application thereof
CN117924621A (en) Multiphase structure modified styrene-butadiene copolymer composite latex
CN110483673A (en) A kind of styrene-butadiene latex and its preparation method and application of Paper Coating heterogeneous structure
CN1072685C (en) Method for prepn. of latex for coating paper
JPH0541756B2 (en)
JP3712296B2 (en) Method for producing copolymer latex for paper coating
EP0991681B1 (en) Paper coating mixtures based on binding agents with n-vinyl formamide derivatives
CN117986425A (en) Modified styrene-butadiene copolymer latex
WO2019069928A1 (en) Emulsion composition

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination