CN111100289A - Branched-chain type wet strength agent and synthesis method thereof - Google Patents
Branched-chain type wet strength agent and synthesis method thereof Download PDFInfo
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- CN111100289A CN111100289A CN201911394139.8A CN201911394139A CN111100289A CN 111100289 A CN111100289 A CN 111100289A CN 201911394139 A CN201911394139 A CN 201911394139A CN 111100289 A CN111100289 A CN 111100289A
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- acid
- wet strength
- strength agent
- branched
- reaction
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Classifications
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
- C08G69/44—Polyester-amides
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
- C08G69/48—Polymers modified by chemical after-treatment
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/20—Macromolecular organic compounds
- D21H17/33—Synthetic macromolecular compounds
- D21H17/46—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- D21H17/54—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen
- D21H17/55—Polyamides; Polyaminoamides; Polyester-amides
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
- D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
- D21H21/18—Reinforcing agents
- D21H21/20—Wet strength agents
Abstract
The invention discloses a branched-chain type wet strength agent, and a synthesis method thereof comprises the following steps: adding polyhydric alcohol which accounts for 0.1-2% of the weight of the polyethylene polyamine and has the functionality of more than or equal to 3 into a polycondensation reaction system of dicarboxylic acid and polyethylene polyamine for copolymerization, and then adding epichlorohydrin for modification to obtain the branched-chain type wet strength agent. Compared with the scheme that the conventional wet strength agent is modified by two-stage epichlorohydrin, the wet strength agent has a slightly branched structure, the branched structure is formed during the first-stage polymerization, the control is easier, the branching degree can be higher, the storage stability and the service performance stability of the final product are better, and the final product also has more excellent application performance. The branched chain type wet strength agent is suitable for the production of paper with wet strength requirement, and improves the wet strength and the wet strength retention rate.
Description
Technical Field
The invention relates to the technical field of papermaking auxiliaries, and particularly relates to a branched-chain type wet strength agent and a synthesis method thereof.
Background
The wet strength agent is an important papermaking auxiliary agent and is widely applied to paper types with wet strength requirements, such as napkin paper, toilet paper, wallpaper, paperboard, banknote paper, fruit bag paper, cup paper and the like. The PAE (polyamideimide epichlorohydrin) type of wet strength agent is one of the most used. Compared with other types of wet strength agents, the PAE wet strength agent has the advantages of no formaldehyde, environmental protection, low toxicity, high performance and the like. Currently, PAE wet strength agents are generally synthesized by the following method: firstly, adopting adipic acid and diethylenetriamine to perform polycondensation to form a linear polymer chain; and in the second step, epichlorohydrin is adopted to modify the polymer obtained in the first step, so as to obtain a cationic polymer aqueous solution with reactivity. The action mechanism of the wet strength agent mainly comprises the following two mechanisms: the wet strength agent and the pulp fiber react to form a cross-linked structure, so that the paper is prevented from almost completely losing strength due to the destruction of hydrogen bonds when meeting water; the wet strength agent and the wet strength agent form a cross-linked network structure to restrain the swelling of the paper pulp fibers when the paper pulp fibers meet water, so that the damage of hydrogen bonds is reduced, and the loss of strength is reduced.
The wet strength agent is used in the wet end of papermaking, and the retention rate of the wet strength agent has great influence on the action effect of the wet strength agent. The conventional wet strength agent on the market at present is prepared by modifying a section of synthesized linear polymer by using epoxy chloropropane, and the one-dimensional diameter is very small in view of molecular structure, so that a certain part of the wet strength agent enters white water during papermaking, and the effective utilization rate and the service performance of the wet strength agent are influenced. If the wet strength agent is made into a branched structure, the retention of the wet strength agent is obviously improved, so that the corresponding application effect can be achieved by using less wet strength agent. Meanwhile, the wet strength agent has a branched structure and is easier to form a net structure when used at a wet end, so that the wet strength of paper is better. Therefore, the application performance of the wet strength agent can be obviously improved after the wet strength agent is made into a branched structure.
Disclosure of Invention
The invention aims to provide a branched-chain type wet strength agent and a synthesis method thereof, which aim to solve the defects in the prior art.
The invention is realized by the following technical scheme:
a method for synthesizing a branched-chain type wet strength agent comprises the following steps: adding polyhydric alcohol which accounts for 0.1-2% of the weight of the polyethylene polyamine and has the functionality of more than or equal to 3 into a polycondensation reaction system of dicarboxylic acid and polyethylene polyamine for copolymerization, and then adding epichlorohydrin for modification to obtain the branched-chain type wet strength agent.
The polyhydric alcohol with the functionality degree of more than or equal to 3 is selected from at least one of glycerol, pentaerythritol, trimethylolethane, xylitol, sorbitol, trimethylolpropane, sucrose, maltose, xylo-oligosaccharide, fructose and glucose; preferred are glycerin, pentaerythritol, trimethylolethane and trimethylolpropane.
Further, the method for synthesizing the branched-chain type wet strength agent comprises the following steps:
step one, adding water, dicarboxylic acid, polyethylene polyamine, polyhydric alcohol with functionality more than or equal to 3 and a catalyst into a reactor, heating to 140-;
and step two, adding water and epoxy chloropropane into the polymer solution obtained in the step one, reacting for 2-10 hours at the temperature of below 50 ℃, adding a termination acid to terminate the reaction, and adjusting the pH value to 2-5 to obtain the branched-chain type wet strength agent.
In the method, the weight parts of the raw materials are as follows:
preferably, the dicarboxylic acid is at least one selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, terephthalic acid, maleic acid, and fumaric acid.
Preferably, the polyethylene polyamine is selected from at least one of diethylenetriamine, triethylenetetramine and tetraethylenepentamine.
Preferably, the catalyst is at least one selected from sulfuric acid, hydrochloric acid, phosphoric acid, p-toluenesulfonic acid, macroporous cation exchange resins and lewis acids.
Preferably, the terminating acid is at least one selected from the group consisting of sulfuric acid, hydrochloric acid, acetic acid, and phosphoric acid.
The invention also provides a branched-chain type wet strength agent prepared by the synthesis method, and the branched-chain type wet strength agent is suitable for production of paper with a wet strength requirement, and improves the wet strength and the wet strength retention rate. Compared with the scheme that the conventional wet strength agent is modified by two-stage epichlorohydrin, the wet strength agent has a slightly branched structure, the technical scheme of the invention forms a branched structure during the first-stage polymerization, the control is easier, the branching degree can be higher, the storage stability and the service performance stability of the final product are better, and the final product also has more excellent application performance.
Detailed Description
The invention is illustrated below by means of specific examples, without being restricted thereto. Unless otherwise specified, each raw material is a commercially available product.
Example 1
Preparation of branched high-performance wet strength agent:
adding 20 g of kettle bottom water, 180 g of diethylenetriamine, 260 g of adipic acid and 1.5 g of glycerol into a reaction kettle, stirring for reaction for 1 hour, adding 1.5 g of catalyst concentrated sulfuric acid, stirring for reaction for 1 hour, continuously heating to 165 ℃ (the reaction temperature is set according to actual requirements) for reaction for 6 hours, adding dilution water after the water yield reaches the design amount, and diluting the polymer until the solid content is 50%. Taking 160 g of the polymer solution, adding 400 g of water, stirring uniformly, adding 45 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for reaction for 6 hours, adding 50% dilute sulfuric acid to terminate the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and adding acid or alkali to adjust the pH to 3.5.
Example 2
Preparation of branched high-performance wet strength agent:
adding 30 g of kettle bottom water, 190 g of diethylenetriamine, 270 g of adipic acid and 2 g of glycerol into a reaction kettle, stirring for reaction for 1 hour, adding 1 g of concentrated sulfuric acid serving as a catalyst, stirring for reaction for 1 hour, continuously heating to 160 ℃ (the reaction temperature is set according to actual requirements), reacting for 5 hours, adding dilution water after the water yield reaches the designed amount, and diluting the polymer to 55% of solid content. Taking 150 g of the polymer solution, adding 450 g of water, stirring uniformly, adding 48 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for 5 hours, adding 50% dilute sulfuric acid to terminate the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and adding acid or alkali to adjust the pH to 3.0.
Example 3
Preparation of branched high-performance wet strength agent:
adding 20 g of kettle bottom water, 180 g of diethylenetriamine, 260 g of adipic acid and 1 g of pentaerythritol into a reaction kettle, stirring for reaction for 1 hour, adding 1.5 g of catalyst p-toluenesulfonic acid, stirring for reaction for 1 hour, continuously heating to 165 ℃ (setting the reaction temperature according to actual requirements) for reaction for 6 hours, adding dilution water after the water yield reaches the designed amount, and diluting the polymer until the solid content is 50%. Taking 160 g of the polymer solution, adding 400 g of water, stirring uniformly, adding 45 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for reaction for 6 hours, adding acetic acid to terminate the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and adding acid or alkali to adjust the pH to 3.5.
Example 4
Preparation of branched high-performance wet strength agent:
adding 30 g of kettle bottom water, 190 g of diethylenetriamine, 270 g of adipic acid and 1.8 g of pentaerythritol into a reaction kettle, stirring for reaction for 1 hour, adding 1 g of catalyst p-toluenesulfonic acid, stirring for reaction for 1 hour, continuously heating to 160 ℃ (the reaction temperature is set according to actual requirements) for reaction for 5 hours, adding dilution water after the water yield reaches the designed amount, and diluting the polymer to 55% of solid content. Taking 150 g of the polymer solution, adding 450 g of water, stirring uniformly, adding 48 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for reaction for 5 hours, adding acetic acid to terminate the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and simultaneously adding acid or alkali to adjust the pH to 3.0.
Example 5
Preparation of branched high-performance wet strength agent:
adding 20 g of kettle bottom water, 180 g of diethylenetriamine, 260 g of adipic acid and 1 g of trimethylolpropane into a reaction kettle, stirring for reaction for 1 hour, adding 1.5 g of catalyst phosphoric acid, stirring for reaction for 1 hour, continuously heating to 165 ℃ (the reaction temperature is set according to actual requirements), reacting for 6 hours, adding dilution water after the water yield reaches the designed amount, and diluting the polymer until the solid content is 50%. Taking 160 g of the polymer solution, adding 400 g of water, stirring uniformly, adding 45 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for reaction for 6 hours, adding hydrochloric acid to stop the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and adding acid or alkali to adjust the pH to 3.5.
Example 6
Preparation of branched high-performance wet strength agent:
adding 30 g of kettle bottom water, 190 g of diethylenetriamine, 270 g of adipic acid and 2 g of trimethylolpropane into a reaction kettle, stirring for reaction for 1 hour, adding 1 g of catalyst phosphoric acid, stirring for reaction for 1 hour, then continuously heating to 160 ℃ (the reaction temperature is set according to actual requirements) for reaction for 5 hours, adding dilution water after the water yield reaches the design amount, and diluting the polymer until the solid content is 55%. Taking 150 g of the polymer solution, adding 450 g of water, stirring uniformly, adding 48 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for 5 hours, adding hydrochloric acid to stop the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and simultaneously adding acid or alkali to adjust the pH to 3.0.
Comparative example
Preparation of a conventional wet strength agent:
adding 20 g of kettle bottom water, 180 g of diethylenetriamine and 260 g of adipic acid into a reaction kettle, stirring for reaction for 1 hour, adding 1.5 g of concentrated sulfuric acid serving as a catalyst, stirring for reaction for 1 hour, continuously heating to 165 ℃ (the reaction temperature is set according to actual requirements), reacting for 6 hours, adding dilution water after the water yield reaches the designed amount, and diluting the polymer until the solid content is 50%. Taking 160 g of the polymer solution, adding 400 g of water, stirring uniformly, adding 45 g of epichlorohydrin, controlling the reaction temperature below 50 ℃ for reaction for 6 hours, adding 50% dilute sulfuric acid to terminate the reaction when the viscosity of the reaction solution reaches the designed viscosity, adding water to adjust the solid content to 12.5%, and adding acid or alkali to adjust the pH to 3.5.
Application examples
Will 400SR softwood pulp and 350SR hardwood pulp is mixed according to the mass ratio of 1:1 and then is pulped to 370And SR. The wet strength agents of the above examples and comparative examples were added in an amount of 120Kg/t of paper (wet/dry, 12.5% solids content by weight) and the basis weight of the finished paper was 50g/m2. In LABTECHAfter the sheet is formed by a 73-62 semi-automatic sheet former, a LABTECH 73-50 standard sheet presser is pressed, the sheet is dried on a sheet quick dryer, and after the sheet is cured in an oven at 105 ℃ for 15 minutes to balance moisture, the dry and wet strength of the paper pattern is detected. The results are shown in Table 1:
TABLE 1 paper sample physical index (temperature/humidity 25 deg.C/40%)
From the above application results, it can be seen that: the branched-chain type wet strength agent prepared in the embodiments 1-6 of the invention has the wet tensile strength improved by 14.5-37.9%, and the application performance of the branched-chain type wet strength agent is obviously better than that of the wet strength agent prepared by the conventional method.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (10)
1. A method for synthesizing a branched-chain wet strength agent is characterized by comprising the following steps: adding polyhydric alcohol which accounts for 0.1-2% of the weight of the polyethylene polyamine and has the functionality of more than or equal to 3 into a polycondensation reaction system of dicarboxylic acid and polyethylene polyamine for copolymerization, and then adding epichlorohydrin for modification to obtain the branched-chain type wet strength agent.
2. The method according to claim 1, wherein the polyol having a functionality of 3 or more is at least one selected from the group consisting of glycerol, pentaerythritol, trimethylolethane, xylitol, sorbitol, trimethylolpropane, sucrose, maltose, xylo-oligosaccharides, fructose, and glucose.
3. The process according to claim 1, wherein the polyol having a functionality of 3 or more is selected from the group consisting of glycerol, pentaerythritol, trimethylolethane and trimethylolpropane.
4. The method of claim 1, comprising the steps of:
step one, adding water, dicarboxylic acid, polyethylene polyamine, polyhydric alcohol with functionality more than or equal to 3 and a catalyst into a reactor, heating to 140-;
and step two, adding water and epoxy chloropropane into the polymer solution obtained in the step one, reacting for 2-10 hours at the temperature of below 50 ℃, adding a termination acid to terminate the reaction, and adjusting the pH value to 2-5 to obtain the branched-chain type wet strength agent.
5. The method of claim 4, wherein the weight parts of each raw material are as follows:
6. the method according to claim 1, wherein the dicarboxylic acid is at least one selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, terephthalic acid, maleic acid, and fumaric acid.
7. The method according to claim 1, wherein the polyethylene polyamine is at least one selected from the group consisting of diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.
8. The method of claim 4, wherein the catalyst is selected from at least one of sulfuric acid, hydrochloric acid, phosphoric acid, p-toluenesulfonic acid, macroporous cation exchange resins, Lewis acids.
9. The method of claim 4, wherein the terminating acid is selected from at least one of sulfuric acid, hydrochloric acid, acetic acid, phosphoric acid.
10. A branched wet strength agent prepared by the process of any one of claims 1 to 9.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911394139.8A CN111100289A (en) | 2019-12-30 | 2019-12-30 | Branched-chain type wet strength agent and synthesis method thereof |
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| CN201911394139.8A CN111100289A (en) | 2019-12-30 | 2019-12-30 | Branched-chain type wet strength agent and synthesis method thereof |
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| CN111100289A true CN111100289A (en) | 2020-05-05 |
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| CN201911394139.8A Pending CN111100289A (en) | 2019-12-30 | 2019-12-30 | Branched-chain type wet strength agent and synthesis method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114456362A (en) * | 2022-02-17 | 2022-05-10 | 九洲生物技术（苏州）有限公司 | Modifier for preparing multi-branched polymer biological latex and preparation method thereof |
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| CN105507076A (en) * | 2014-09-22 | 2016-04-20 | 丹阳市华兴纸箱有限公司 | Wet strengthening agent and preparation method thereof |
| CN106283875A (en) * | 2016-08-30 | 2017-01-04 | 雷春生 | A kind of preparation method of composite paper wet strength agent |
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Application publication date: 20200505 |