CN119736815B - Cationic polyurethane wet strength agent for papermaking and preparation method thereof - Google Patents
Cationic polyurethane wet strength agent for papermaking and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a cationic polyurethane wet strength agent for papermaking and a preparation method thereof, belongs to the technical field of papermaking additive processing, and is used for solving the technical problem that the wet tensile strength of the cationic polyurethane wet strength agent in the prior art on a papermaking sample is to be further improved in effect; the invention comprises 60-70 parts by weight of polyurethane emulsion, 4-6 parts by weight of modified polyethylenimine and 2.8-3.2 parts by weight of chitosan mixture, and the invention effectively improves the wet tensile strength and the retention rate of the tensile strength of a papermaking sample by preparing cationic polyurethane emulsion containing quaternary ammonium salt blocks and matching the cationic polyurethane emulsion with the modified polyethylenimine and the chitosan mixture.
Description
Technical Field
The invention relates to the technical field of papermaking additive processing, in particular to a cationic polyurethane wet strength agent for papermaking and a preparation method thereof.
Background
In the paper industry, wet strength is an important index for measuring the mechanical properties of paper in a wet environment, and particularly for special-purpose paper such as packaging paper, medical paper, label paper and the like, high wet strength is an indispensable performance requirement, and a wet strength agent is an important auxiliary agent, so that the strength of the paper in the wet state can be remarkably improved, and the paper can still maintain good physical properties in the wet environment.
In the prior art, chinese patent publication No. CN105085906A discloses a preparation method of a papermaking wet strength agent, which comprises the following steps of (1) polymerizing polyamine, adipic acid ester, dimer acid and a catalyst under heating to obtain a polyamide polyamine prepolymer aqueous solution, (2) adding water, a cationic etherifying agent and epoxy chloropropane into the prepolymer aqueous solution, reacting at room temperature, heating to react, and finally adding acid to adjust the pH value to obtain the papermaking wet strength agent with the solid content of 15-35 percent.
However, the polyurethane type wet strength agent in the prior art has insufficient cationic property, has weak bonding force with negatively charged cellulose fibers, and is affected by dispersibility in aqueous solution, so that the polyurethane type wet strength agent can be distributed uniformly in papermaking pulp, and the wet tensile strength of a papermaking sample needs to be further improved.
In view of the technical drawbacks of this aspect, a solution is now proposed.
Disclosure of Invention
The invention aims to provide a cationic polyurethane wet strength agent for papermaking and a preparation method thereof, which are used for solving the technical problem that the wet tensile strength of the cationic polyurethane wet strength agent in the prior art on a papermaking sample is to be further improved.
The invention aims at realizing the technical scheme that the cationic polyurethane wet strength agent for papermaking comprises, by weight, 60-70 parts of polyurethane emulsion, 4-6 parts of modified polyethyleneimine and 2.8-3.2 parts of chitosan mixture;
The preparation method of the polyurethane emulsion comprises the steps of mixing polytetrahydrofuran ether glycol, dihydroxyquaternary ammonium salt, a catalyst and tetrahydrofuran under the protection of inert gas, raising the temperature of a reaction system to 60-65 ℃, dropwise adding a diisocyanate solution into the reaction system, carrying out heat preservation reaction for 2-3h, dropwise adding trimethylolethane into the reaction system, carrying out heat preservation reaction for 50-60min, adding 2- (2-aminoethyl) 1, 3-propanediol into the reaction system, carrying out heat preservation reaction for 40-60min, and carrying out aftertreatment to obtain the polyurethane emulsion.
The synthetic reaction formula of the polyurethane emulsion is as follows:
Wherein:
;
。
the synthetic reaction mechanism of the polyurethane emulsion is as follows:
In the reaction process, hydroxyl on polytetrahydrofuran ether glycol or dihydroxyquaternary ammonium salt molecules and isocyanate groups on isophorone diisocyanate molecules are subjected to condensation reaction to generate urethane bonds, polyurethane prepolymer which is co-embedded by polytetrahydrofuran ether glycol and dihydroxyquaternary ammonium salt is formed, three hydroxyl groups in trimethylolethane react with isocyanate groups in the prepolymer to generate polyurethane with a three-dimensional network structure, amino on 2- (2-aminoethyl) 1, 3-propanediol molecules has higher activity, the polyurethane can react with terminal isocyanate groups on polyurethane molecules preferentially, dihydroxyl end-capped is formed on polyurethane molecules, and the polyurethane emulsion with different solid contents is prepared by high-speed emulsification and dispersion of solvent water and controlled water addition.
Further, the chitosan mixture consists of chitosan quaternary ammonium salt and carboxymethyl cellulose according to the weight ratio of 3:1.
Further, the dosage ratio of polytetrahydrofuran ether glycol, dihydroxyquaternary ammonium salt, catalyst, tetrahydrofuran, diisocyanate solution, trimethylolethane and 2- (2-aminoethyl) 1, 3-propanediol is 5g:2g:0.1g:8 g:2g:1g, the catalyst is dibutyltin dilaurate, the diisocyanate solution consists of isophorone diisocyanate and tetrahydrofuran according to 1g:1g, the post-treatment comprises the steps of reducing the temperature of a reaction system to room temperature after the reaction is finished, adding purified water into the reaction system, emulsifying and dispersing for 30-50min, and obtaining the polyurethane emulsion with the solid content of 15-20%.
Further, the preparation method of the dihydroxyquaternary ammonium salt comprises the steps of stirring and mixing 1,1' - (butylimino) dimethanol and 1-chlorobutane in a closed environment, placing a reaction system in a heat exchange medium at 140-150 ℃, carrying out heat preservation reaction for 35-40h, and carrying out post-treatment to obtain the dihydroxyquaternary ammonium salt.
The synthetic reaction formula of the dihydroxyquaternary ammonium salt is as follows:
the synthetic reaction mechanism of the dihydroxyquaternary ammonium salt is as follows:
In the reaction process, nitrogen atoms with lone pair electrons in 1,1' - (butylimino) dimethanol are taken as nucleophilic active sites to attack carbon atoms in 1-chlorobutane, the nitrogen atoms and the carbon atoms form partial bonds, meanwhile, chlorine atoms are taken as leaving groups, the bonds of the chlorine atoms and the carbon atoms are gradually broken and separated to form a five-coordination transition state, the nitrogen atoms and the carbon atoms form stable C-N bonds to generate quaternary ammonium salt, and the dihydroxyquaternary ammonium salt is prepared;
Mass spectrometry data for dihydroxyquaternary ammonium salts were:
m/z 225.1496 (100.0%), 227.1466 (32.0%), 226.1529 (10.8%), 228.1500 (3.5%), molecular weight 225.76.
Further, the dosage ratio of the 1,1' - (butylimino) dimethanol to the 1-chlorobutane is 1mol:1.3mol, and the post-treatment comprises the steps of reducing the temperature of a reaction system to 60-70 ℃ after the reaction is finished, and evaporating low-boiling substances under reduced pressure to obtain the dihydroxyquaternary ammonium salt.
The preparation method of the modified polyethyleneimine solution comprises the steps of mixing polyethyleneimine, ethanol solution, catalyst and sodium carbonate, stirring until the polyethyleneimine, ethanol solution, catalyst and sodium carbonate are dissolved, raising the temperature of a reaction system to 50-60 ℃, adding epichlorohydrin into the reaction system, carrying out heat preservation reaction for 2-3h, and carrying out aftertreatment to obtain the modified polyethyleneimine.
The synthesis reaction formula of the modified polyethyleneimine solution is as follows:
the synthetic reaction mechanism of the modified polyethyleneimine is as follows:
In the reaction process, ethanol is used as an organic solvent, so that the polarity of water is reduced, the possibility of ring opening of epoxy groups is reduced, tetrabutylammonium bromide is used as a phase transfer catalyst, sodium carbonate provides weak alkaline conditions, nucleophilic substitution reaction between halogen on epichlorohydrin molecules and amino in polyethyleneimine is promoted, ring opening condensation of epoxy groups is avoided, and epoxy group modified polyethyleneimine is prepared.
Further, the dosage ratio of the polyethyleneimine to the ethanol solution to the catalyst to the sodium carbonate to the epichlorohydrin is 5g to 10mL to 0.1g to 1.5g to 1.3g, the ethanol solution is 60-70vol% ethanol water solution, the catalyst is tetrabutylammonium bromide, the post-treatment comprises the steps of adjusting the pH value of a reaction system to be 7 after the reaction is finished, raising the temperature of the reaction system to 70 ℃, and evaporating low-boiling substances under reduced pressure to obtain the modified polyethyleneimine.
The invention also provides a preparation method of the cationic polyurethane wet strength agent for papermaking, which is characterized in that the cationic wet strength agent is obtained by uniformly mixing polyurethane emulsion, modified polyethyleneimine solution and chitosan mixture.
The invention has the following beneficial effects:
1. The cationic polyurethane wet strength agent for papermaking is prepared by taking isophorone diisocyanate as a cross-linking agent, trimethylolethane as a cross-linking agent and 2- (2-aminoethyl) 1, 3-propanediol as a blocking agent, and the polyurethane emulsion is prepared by block-crosslinking polytetrahydrofuran ether glycol and dihydroxyquaternary ammonium salt, wherein quaternary ammonium salt introduced on a polyurethane molecular chain can be combined with cellulose fibers with negative charges in papermaking pulp through electrostatic adsorption, so that a hydrogen bond network among pulp fibers is enhanced, polytetrahydrofuran ether glycol in polyurethane molecules is used as a hydrophobic chain segment with flexibility, dynamic rearrangement occurs in a wet environment, the damaged bonding is partially compensated through hydrogen bond recombination, moisture permeation is resisted by the polyurethane emulsion and the cross-linked network of polyurethane molecules, the damage of hydrogen bonds among fibers is slowed down, and the wet strength is maintained.
2. According to the cationic polyurethane wet strength agent for papermaking, the polyethyleneimine is modified, a large number of non-hydrophilic epoxy groups are modified on a hydrophilic polyethyleneimine molecular chain, so that the polyethyleneimine is easier to disperse in polyurethane emulsion, a hydrophobic chain segment of polyurethane and a hydrophilic chain segment of modified polyethyleneimine are combined to improve the stability of paper in a wet environment, unreacted amine groups on the modified polyethyleneimine molecular chain can form hydrogen bonds with water molecules in water and accept protons in water to carry positive charges, the modified polyethyleneimine molecular chain can be combined with cellulose fibers carrying negative charges in papermaking pulp through electrostatic adsorption, and epoxy groups can be opened under proper conditions to carry out condensation polymerization reaction with hydroxyl groups, amino groups and other active groups in papermaking pulp molecules to generate covalent bonds such as imine, ether bonds and the like, and the covalent bonds are formed without breaking due to wetting of paper, so that the tensile strength of a papermaking sample under the wet condition is further improved.
3. According to the cationic polyurethane wet strength agent for papermaking, chitosan quaternary ammonium salt and carboxymethyl cellulose are mixed to form a chitosan mixture, the chitosan quaternary ammonium salt contains cationic groups on molecules, and can be combined with cellulose fibers with negative charges through electrostatic adsorption, the chitosan mixture is matched with modified quaternary ammonium salt and modified polyethyleneimine in polyurethane emulsion, so that a hydrogen bond network among papermaking fibers is further enhanced, the permeability of the wet strength agent is regulated through the hydrophilic performance of the chitosan quaternary ammonium salt and the hydroxymethyl cellulose, the wet strength agent can be more uniformly dispersed in papermaking slurry, crosslinking is promoted to be more uniform, and the wet tensile strength of a papermaking sample is further improved.
Detailed Description
The technical solutions of the present invention will be clearly and completely described in connection with the embodiments, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the application, the molecular weight of polytetrahydrofuran ether glycol is 650+/-25, and the hydroxyl number is 166.2-179.5mgKOH/g;
In the application, the chitosan quaternary ammonium salt is selected from the green-biphenyl (Jining) chemical technology Co., ltd, the chemical name is hydroxypropyl trimethyl ammonium chloride chitosan, and the content is 90%;
in the present application, the polyethyleneimine is selected from Hubei Yamaide biological medicine Co., ltd, has a molecular weight of 5000, a density of 1.030g/mL at 25 ℃, a boiling point of 250 ℃ and a melting point of 59-60 ℃.
Example 1
The embodiment provides a preparation method of a cationic polyurethane wet strength agent for papermaking, which comprises the following steps:
S1, preparing dihydroxyl quaternary ammonium salt
1,1' - (Butylimino) dimethanol 133.2g and 1-chlorobutane 120.3g are weighed and added into a three-neck flask to be sealed, the three-neck flask is fixed in an oil bath pot with mechanical stirring, the temperature of the oil bath is set to 140 ℃, the temperature of the oil bath is kept for reaction for 35 hours, the temperature of the three-neck flask is reduced to 60 ℃, and low-boiling substances are distilled off under reduced pressure, so that the dihydroxyquaternary ammonium salt is obtained.
S2, preparing polyurethane emulsion
Uniformly mixing isophorone diisocyanate and tetrahydrofuran according to a weight ratio of 1:1 to obtain a diisocyanate solution;
50g of polytetrahydrofuran ether glycol, 20g of dihydroxyquaternary ammonium salt, 1g of dibutyltin dilaurate and 80mL of tetrahydrofuran are weighed and added into a three-neck flask protected by nitrogen, the temperature of the three-neck flask is increased to 60 ℃, 80g of diisocyanate solution is dropwise added into the three-neck flask, the reaction is carried out for 2 hours in a heat-preserving manner, 20g of trimethylolethane is dropwise added into the three-neck flask, the reaction is carried out for 50 minutes in a heat-preserving manner, 10g of 2- (2-aminoethyl) 1, 3-propanediol is added into the three-neck flask, the reaction is carried out for 40 minutes in a heat-preserving manner, the temperature of the three-neck flask is reduced to room temperature, purified water is added into the three-neck flask, and the polyurethane emulsion with the solid content of 15% is obtained after emulsification and dispersion for 30 minutes.
S3, preparing modified polyvinyl amide solution
50G of polyethyleneimine, 100mL of 60vol% ethanol aqueous solution, 1g of tetrabutylammonium bromide and 15g of sodium carbonate are weighed and added into a three-neck flask, the temperature of the three-neck flask is increased to 50 ℃, the three-neck flask is stirred until the system is dissolved, 13g of epichlorohydrin is added into the three-neck flask, the reaction is carried out for 2 hours under the heat preservation, the pH=7 of the reaction system is regulated, the temperature of the reaction system is increased to 70 ℃, and low-boiling-point substances are distilled off under reduced pressure, so that the modified polyethyleneimine is obtained.
S4, preparing chitosan mixture
Mixing chitosan quaternary ammonium salt and carboxymethyl cellulose according to a weight ratio of 3:1 to obtain a chitosan mixture.
S5, preparing a cationic wet strength agent
Weighing 60 parts of polyurethane emulsion, 15 parts of modified polyethyleneimine solution and 2.8 parts of chitosan mixture according to parts by weight, and uniformly mixing to obtain the cationic wet strength agent.
Example 2
The embodiment provides a preparation method of a cationic polyurethane wet strength agent for papermaking, which comprises the following steps:
S1, preparing dihydroxyl quaternary ammonium salt
1,1' - (Butylimino) dimethanol 133.2g and 1-chlorobutane 120.3g are weighed and added into a three-neck flask to be sealed, the three-neck flask is fixed in an oil bath pot with mechanical stirring, the temperature of the oil bath is set to 145 ℃, the temperature of the oil bath is kept for reaction for 37 hours, the temperature of the three-neck flask is reduced to 65 ℃, and low-boiling substances are distilled off under reduced pressure, so that the dihydroxyquaternary ammonium salt is obtained.
S2, preparing polyurethane emulsion
Uniformly mixing isophorone diisocyanate and tetrahydrofuran according to a weight ratio of 1:1 to obtain a diisocyanate solution;
50g of polytetrahydrofuran ether glycol, 20g of dihydroxyquaternary ammonium salt, 1g of dibutyltin dilaurate and 80mL of tetrahydrofuran are weighed and added into a three-neck flask protected by nitrogen, the temperature of the three-neck flask is increased to 63 ℃, 80g of diisocyanate solution is dropwise added into the three-neck flask, the reaction is kept for 2.5h, 20g of trimethylolethane is dropwise added into the three-neck flask, the reaction is kept for 55min, 10g of 2- (2-aminoethyl) 1, 3-propanediol is added into the three-neck flask, the reaction is kept for 50min, the temperature of the three-neck flask is reduced to room temperature, purified water is added into the three-neck flask, and the emulsion dispersion is carried out for 40min, thus obtaining the polyurethane emulsion with 17% solid content.
S3, preparing modified polyvinyl amide solution
50G of polyethyleneimine, 100mL of 65vol% ethanol aqueous solution, 1g of tetrabutylammonium bromide and 15g of sodium carbonate are weighed and added into a three-neck flask, the temperature of the three-neck flask is increased to 55 ℃, the three-neck flask is stirred until the system is dissolved, 13g of epichlorohydrin is added into the three-neck flask, the reaction is carried out for 2.5 hours under the heat preservation, the pH value of the reaction system is regulated to be 7, the temperature of the reaction system is increased to 70 ℃, and low-boiling-point substances are distilled off under reduced pressure, so that the modified polyethyleneimine is obtained.
S4, preparing chitosan mixture
Mixing chitosan quaternary ammonium salt and carboxymethyl cellulose according to a weight ratio of 3:1 to obtain a chitosan mixture.
S5, preparing a cationic wet strength agent
Weighing 65 parts of polyurethane emulsion, 17 parts of modified polyethyleneimine solution and 3 parts of chitosan mixture according to parts by weight, and uniformly mixing to obtain the cationic wet strength agent.
Example 3
The embodiment provides a preparation method of a cationic polyurethane wet strength agent for papermaking, which comprises the following steps:
S1, preparing dihydroxyl quaternary ammonium salt
1,1' - (Butylimino) dimethanol 133.2g and 1-chlorobutane 120.3g are weighed and added into a three-neck flask to be sealed, the three-neck flask is fixed in an oil bath pot with mechanical stirring, the temperature of the oil bath is set to 150 ℃, the temperature of the oil bath is kept for 40 hours, the temperature of the three-neck flask is reduced to 70 ℃, and low-boiling substances are distilled off under reduced pressure, so that the dihydroxyquaternary ammonium salt is obtained.
S2, preparing polyurethane emulsion
Uniformly mixing isophorone diisocyanate and tetrahydrofuran according to a weight ratio of 1:1 to obtain a diisocyanate solution;
50g of polytetrahydrofuran ether glycol, 20g of dihydroxyquaternary ammonium salt, 1g of dibutyltin dilaurate and 80mL of tetrahydrofuran are weighed and added into a three-neck flask protected by nitrogen, the temperature of the three-neck flask is increased to 65 ℃, 80g of diisocyanate solution is dropwise added into the three-neck flask, the reaction is carried out for 3 hours in a heat-preserving manner, 20g of trimethylolethane is dropwise added into the three-neck flask, the reaction is carried out for 60 minutes in a heat-preserving manner, 10g of 2- (2-aminoethyl) 1, 3-propanediol is added into the three-neck flask, the reaction is carried out for 60 minutes in a heat-preserving manner, the temperature of the three-neck flask is reduced to room temperature, purified water is added into the three-neck flask, and the emulsion dispersion is carried out for 50 minutes, thus obtaining the polyurethane emulsion with the solid content of 20%.
S3, preparing modified polyvinyl amide solution
50G of polyethyleneimine, 100mL of 70vol% ethanol aqueous solution, 1g of tetrabutylammonium bromide and 15g of sodium carbonate are weighed and added into a three-neck flask, the temperature of the three-neck flask is increased to 60 ℃, the three-neck flask is stirred until the system is dissolved, 13g of epichlorohydrin is added into the three-neck flask, the reaction is carried out for 3 hours under the condition of heat preservation, the pH=7 of the reaction system is regulated, the temperature of the reaction system is increased to 70 ℃, and low-boiling-point substances are distilled off under reduced pressure, so that the modified polyethyleneimine is obtained.
S4, preparing chitosan mixture
Mixing chitosan quaternary ammonium salt and carboxymethyl cellulose according to a weight ratio of 3:1 to obtain a chitosan mixture.
S5, preparing a cationic wet strength agent
Weighing 70 parts of polyurethane emulsion, 4-6 parts of modified polyethyleneimine and 3.2 parts of chitosan mixture according to parts by weight, and uniformly mixing to obtain the cationic wet strength agent.
Comparative example 1
The present comparative example is different from example 3 in that the added amount of the dihydroxyquaternary ammonium salt in step S2 is 10g.
Comparative example 2
The present comparative example differs from example 3 in that step S3 was omitted and the modified polyethylenimine in step S5 was replaced with the polyethylenimine in step S3.
Comparative example 3
The present comparative example differs from example 3 in that step S4 was omitted and no chitosan mixture was added in step S5.
Performance test:
the cationic wet strength agents prepared in examples 1 to 3 and comparative examples 1 to 3 were added to the papermaking slurry in an amount of 20kg/t for papermaking, and a papermaking sample having a basis weight of 100g/m 2 was prepared, and a papermaking sample prepared without adding the cationic wet strength agent was used as a blank;
the tensile strength, i.e., dry tensile strength, of the paper-making test pieces prepared in examples 1 to 3 and comparative examples 1 to 3 was measured with reference to standard GB/T12914-2018 "measurement of tensile strength of paper and paperboard constant speed stretching method (20 mm/min)";
The tensile strength after soaking, that is, wet tensile strength of the paper-making test pieces prepared in examples 1 to 3 and comparative examples 1 to 3 was measured with reference to standard GB/T465.2-2008 "measurement of tensile Strength after soaking paper and cardboard";
According to the formula The retention of tensile strength after wetting of the paper-making test pieces prepared in examples 1-3 and comparative examples 1-3 was measured, where P Wet state is the wet tensile strength of the test pieces and P Dry is the wet tensile strength of the test pieces, and the specific test results are shown in Table 1 below.
Data analysis:
The data in the table 1 are compared and analyzed, the cationic wet strength agent for papermaking prepared by the invention is added into papermaking slurry according to the addition amount of 20kg/t, the wet tensile strength of the prepared papermaking sample reaches 12.15kN/m, the retention rate of the tensile strength reaches 22.41%, and all detection data are superior to those of the comparative example, so that the cationic polyurethane emulsion containing quaternary ammonium salt blocks is prepared and matched with the modified polyethyleneimine and chitosan mixture, and the wet tensile strength and the retention rate of the papermaking sample are effectively improved.
The preferred embodiments of the invention disclosed above are intended only to assist in the explanation of the invention. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand and utilize the invention. The invention is limited only by the claims and the full scope and equivalents thereof.
Claims (6)
1. The cationic polyurethane wet strength agent for papermaking is prepared by fully mixing polyurethane emulsion, modified polyethyleneimine and chitosan mixture, and is characterized by further comprising the steps of mixing polytetrahydrofuran ether glycol, dihydroxyquaternary ammonium salt, a catalyst and tetrahydrofuran under the protection of inert gas, raising the temperature of a reaction system to 60-65 ℃, dropwise adding a diisocyanate solution into the reaction system, carrying out heat preservation reaction for 2-3h, dropwise adding trimethylolethane into the reaction system, carrying out heat preservation reaction for 50-60min, adding 2- (2-aminoethyl) 1, 3-propanediol into the reaction system, carrying out heat preservation reaction for 40-60min, and carrying out aftertreatment to obtain polyurethane emulsion;
the chitosan mixture consists of chitosan quaternary ammonium salt and carboxymethyl cellulose according to the weight ratio of 3:1;
Mixing polyethylene imine, ethanol solution, a catalyst and sodium carbonate, stirring until the system is dissolved, increasing the temperature of a reaction system to 50-60 ℃, adding epichlorohydrin into the reaction system, carrying out heat preservation reaction for 2-3h, and carrying out aftertreatment to obtain modified polyethylene imine;
The cationic polyurethane wet strength agent is prepared by fully mixing 60-70 parts by weight of polyurethane emulsion, 4-6 parts by weight of modified polyethyleneimine and 2.8-3.2 parts by weight of chitosan mixture.
2. The cationic wet strength agent for papermaking according to claim 1, wherein the dosage ratio of polytetrahydrofuran ether glycol, dihydroxyquaternary ammonium salt, catalyst, tetrahydrofuran, diisocyanate solution, trimethylolethane and 2- (2-aminoethyl) 1, 3-propanediol is 5g:2g:0.1g:8ml:8g:2g:1g, the catalyst is dibutyltin dilaurate, the diisocyanate solution is composed of isophorone diisocyanate and tetrahydrofuran in 1g:1g, the post-treatment comprises the steps of reducing the temperature of the reaction system to room temperature after the completion of the reaction, adding purified water into the reaction system, and emulsifying and dispersing for 30-50min to obtain a polyurethane emulsion with a solid content of 15-20%.
3. The cationic polyurethane wet strength agent for papermaking according to claim 1, wherein the dihydroxyquaternary ammonium salt is prepared by stirring and mixing 1,1' - (butylimino) dimethanol and 1-chlorobutane in a closed environment, placing a reaction system in a heat exchange medium at 140-150 ℃, carrying out heat preservation reaction for 35-40h, and carrying out post-treatment.
4. The cationic polyurethane wet strength agent for papermaking according to claim 3, wherein the dosage ratio of 1,1' - (butylimino) dimethanol to 1-chlorobutane is 1mol:1.3mol, and the post-treatment comprises the steps of reducing the temperature of a reaction system to 60-70 ℃ after the reaction is completed, and evaporating low-boiling substances under reduced pressure to obtain the dihydroxyquaternary ammonium salt.
5. The cationic polyurethane wet strength agent for papermaking according to claim 1, wherein the dosage ratio of the polyethyleneimine to the ethanol solution to the catalyst to the sodium carbonate to the epichlorohydrin is 5g to 10mL to 0.1g to 1.5g to 1.3g, the ethanol solution is 60-70vol% ethanol water solution, the catalyst is tetrabutylammonium bromide, and the post-treatment comprises the steps of adjusting the pH=7 of a reaction system after the reaction is completed, raising the temperature of the reaction system to 70 ℃, and evaporating low-boiling-point substances under reduced pressure to obtain the modified polyethyleneimine.
6. The method for preparing a cationic wet strength agent for papermaking according to any one of claims 1-5, wherein the cationic wet strength agent is obtained by uniformly mixing polyurethane emulsion, modified polyethyleneimine solution and chitosan mixture.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1108546A (en) * | 1964-06-26 | 1968-04-03 | Chemirad Corp | Polyisocyanate and cellulose fibrous products |
| CN115125762A (en) * | 2022-07-12 | 2022-09-30 | 龙游富田造纸精化有限公司 | Low-chlorine environment-friendly papermaking wet strength agent and production process thereof |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2003013394A (en) * | 2001-06-27 | 2003-01-15 | Dai Ichi Kogyo Seiyaku Co Ltd | Wet paper strength enhancing composition |
| JP2003138497A (en) * | 2001-10-31 | 2003-05-14 | Dai Ichi Kogyo Seiyaku Co Ltd | Wet strength agent |
| JP4688014B2 (en) * | 2003-06-30 | 2011-05-25 | 荒川化学工業株式会社 | Paper additive and paper using the paper additive |
| CA2847443A1 (en) * | 2011-09-01 | 2013-03-07 | Nanopaper, Llc | Additives for papermaking |
| CN106589298A (en) * | 2016-11-08 | 2017-04-26 | 河北省科学院能源研究所 | Organosilicon-modified cationic aqueous polyurethane paper wet strength agent and preparation method |
| CN113087898B (en) * | 2021-04-15 | 2022-09-09 | 浙江九本环保技术有限公司 | Preparation method and application of polyamide polyamine-polyester block type low-organochlorine wet strength agent |
| CN119434030B (en) * | 2024-12-10 | 2025-06-17 | 建滔（佛冈）绝缘材料有限公司 | Halogen-free laminate base paper and preparation method and application thereof |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1108546A (en) * | 1964-06-26 | 1968-04-03 | Chemirad Corp | Polyisocyanate and cellulose fibrous products |
| CN115125762A (en) * | 2022-07-12 | 2022-09-30 | 龙游富田造纸精化有限公司 | Low-chlorine environment-friendly papermaking wet strength agent and production process thereof |
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Denomination of invention: A cationic polyurethane wet strength agent for papermaking and its preparation method Granted publication date: 20250509 Pledgee: The Bank of Hangzhou Fuyang branch of the new Limited by Share Ltd. Pledgor: ZHEJIANG JIUBEN BIOLOGICAL CHEMICAL CO.,LTD. Registration number: Y2025980019778 |