CN111333784B - Preparation method of super absorbent water-retaining resin - Google Patents
Preparation method of super absorbent water-retaining resin Download PDFInfo
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- CN111333784B CN111333784B CN202010211437.5A CN202010211437A CN111333784B CN 111333784 B CN111333784 B CN 111333784B CN 202010211437 A CN202010211437 A CN 202010211437A CN 111333784 B CN111333784 B CN 111333784B
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
- C08F283/006—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polymers provided for in C08G18/00
- C08F283/008—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polymers provided for in C08G18/00 on to unsaturated polymers
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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
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/38—Low-molecular-weight compounds having heteroatoms other than oxygen
- C08G18/3878—Low-molecular-weight compounds having heteroatoms other than oxygen having phosphorus
- C08G18/388—Low-molecular-weight compounds having heteroatoms other than oxygen having phosphorus having phosphorus bound to carbon and/or to hydrogen
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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
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/48—Polyethers
- C08G18/4833—Polyethers containing oxyethylene units
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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
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/65—Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
- C08G18/66—Compounds of groups C08G18/42, C08G18/48, or C08G18/52
- C08G18/6666—Compounds of group C08G18/48 or C08G18/52
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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
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/67—Unsaturated compounds having active hydrogen
- C08G18/671—Unsaturated compounds having only one group containing active hydrogen
- C08G18/672—Esters of acrylic or alkyl acrylic acid having only one group containing active hydrogen
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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
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
- C08G18/72—Polyisocyanates or polyisothiocyanates
- C08G18/73—Polyisocyanates or polyisothiocyanates acyclic
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
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- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polyurethanes Or Polyureas (AREA)
Abstract
The invention provides a preparation method of a super absorbent water-retaining resin, which comprises the following specific steps: preparing polyethylene glycol 2000, phosphorous acid, dibutyl tin dilaurate, hexamethylene diisocyanate and 2-hydroxyethyl acrylate into a phosphorus-containing polyurethane surfactant; and the high water absorption and retention resin is obtained after the high water absorption and retention resin is uniformly stirred by using an acrylic acid and acrylamide polymerization system with the neutralization degree reaching 95 percent. The invention applies the phosphorus-containing polyurethane surfactant to the production of the resin, connects phosphorus in the phosphorus-containing polyurethane surfactant to the middle of a molecular chain, and then applies the phosphorus-containing polyurethane surfactant to the resin to improve the molecular strength of the resin, thereby improving the water absorption and water retention rate and the use times of the resin, effectively preventing the water and soil loss of the seedlings by using the resin in the planting of the seedlings, improving the survival rate of the seedlings, and saving the later irrigation and maintenance cost and the labor investment.
Description
Technical Field
The invention relates to the field of resins, in particular to a preparation method of a super absorbent water-retaining resin.
Background
In the process of economic high-speed development, the large-scale construction of roads is accompanied, and meanwhile, the ecological environment is damaged by road construction engineering. In order to repair the influence of road alignment on the ecological system, the damage of road engineering construction on the environment and road traffic on the environment, people continuously research and practice the road greening theory, technology and method for a long time. The road greening can effectively improve traffic environment by planting flowers, plants and trees, and can achieve the effects of inducing vision, shading, anti-dazzling, buffering, coordinating and beautifying, marking, protecting environment and the like.
A significant part of road greening is seedling planting, which requires sufficient continuous moisture to ensure its growth, but most of the water is lost by evaporation during irrigation, resulting in water-starvation death of the seedlings. In order to prevent water loss and ensure survival of seedlings, the watering times are increased, but the watering time and the labor are consumed, water resources are wasted, and maintenance cost is increased; secondly, water-absorbing and water-retaining resin can be added into the soil for planting the seedlings so as to increase the water storage capacity and reduce the water evaporation speed, and the seedlings can be ensured to be continuously moistened under the condition of reducing the irrigation times, and the seedlings are not dead due to water shortage. The current commercial resin has limited water absorption and retention effects, short service life, unobvious promotion of the effect of promoting reduction of irrigation times, frequent replacement is required to ensure the effect, and cost investment is increased. Therefore, for road greening, arid and semiarid regions or regions with rapid water and soil loss and rapid weathering, the resin with strong water retention and water absorption effects and long service life is needed to assist in preventing the water and soil loss of seedlings, improving the survival rate of the seedlings, and saving the later irrigation maintenance cost and the labor investment. The invention aims to research the resin with high water absorption and water retention and long service life.
Disclosure of Invention
The invention aims to provide a preparation method of a high-water-absorption water-retention resin, which can be used for preparing and producing the resin with high-efficiency water absorption and water retention effects and obviously prolonged service life.
A preparation method of a super absorbent water-retaining resin comprises the following specific steps:
(1) Cooling the prepared phosphorus-containing polyurethane surfactant to 38-42 ℃, and rapidly stirring and dispersing under the condition of 8000 rpm;
(2) Adding 90-110 parts by weight of acrylic acid and 70-90 parts by weight of an acrylamide polymerization system into the step (1), and uniformly stirring under the condition of 8000 rpm;
(3) Stirring, heating to 68-72 ℃, adding 0.5-1.5 parts of potassium persulfate for reaction, reacting at constant temperature for 100-140 min, and crushing to obtain the water-absorbing and water-retaining resin.
The acrylic acid and acrylamide polymerization system is obtained by mixing acrylic acid and acrylamide with the neutralization degree reaching 95-98 percent.
The phosphorus-containing polyurethane surfactant is prepared by mixing and reacting the following components in parts by weight: 10 to 20 parts of polyethylene glycol 2000, 0.5 to 2 parts of phosphorous acid, 0.01 to 0.1 part of dibutyltin dilaurate, 5 to 10 parts of hexamethylene diisocyanate and 10 to 20 parts of 2-hydroxyethyl acrylate.
The preparation method of the phosphorus-containing polyurethane surfactant comprises the following steps:
(1) Uniformly mixing polyethylene glycol 2000, phosphorous acid, dibutyl tin dilaurate and hexamethylene diisocyanate, heating to 80-82 ℃, and reacting for 100-140 min;
(2) Adding acrylic acid-2-hydroxyethyl into the reaction system, and continuing to react for 0.5-1.5 min to obtain the phosphorus-containing polyurethane surfactant.
The invention has the following beneficial effects:
(1) The invention applies the phosphorus-containing polyurethane surfactant to the production of the resin, and the phosphorus in the phosphorus-containing polyurethane surfactant is connected to the middle of a molecular chain and then applied to the resin to improve the molecular strength, the water absorption and retention rate of the resin and the use times. The novel seedling planting device is used in seedling planting, effectively prevents water and soil loss of seedlings, improves the survival rate of the seedlings, and saves the later irrigation maintenance cost and the labor investment.
(2) The invention connects phosphorus to the main chain of the polyamino acid surfactant, then connects hydroxyl-containing acrylic acid, finally further polymerizes with acrylic acid, acrylamide and the like to form polyurethane super absorbent water retention resin containing phosphorus in molecular chain
The main chain of the water-absorbing and water-retaining resin molecule is connected with phosphorus element to make the phosphorus element become water-absorbing and water-retainingThe introduction of phosphorus at the linking points on the main chain of the resin improves the scale and corrosion inhibition effect of the resin and improves the water absorption and retention properties and the reuse properties of the water-absorbent resin.
Drawings
FIG. 1 is a graph of the water retention of resins with and without the addition of phosphorus-containing polyurethane surfactant at different temperature conditions.
FIG. 2 is a graph of the liquid absorption of resins with and without the addition of a phosphorus-containing polyurethane surfactant at various times of water absorption.
Detailed Description
Example 1
A preparation method of a super absorbent water-retaining resin comprises the following specific steps:
(1) Uniformly mixing 10 parts by weight of polyethylene glycol 2000, 0.5 part by weight of phosphorous acid, 0.01 part by weight of dibutyltin dilaurate and 5 parts by weight of hexamethylene diisocyanate, heating to 80 ℃ and reacting for 100min;
(2) Adding 10 parts of 2-hydroxyethyl acrylate into a reaction system, and continuously reacting for 0.5min to obtain a phosphorus-containing polyurethane surfactant;
(3) Cooling the prepared phosphorus-containing polyurethane surfactant to a temperature lower than 38 ℃, and rapidly stirring and dispersing under the condition of 8000 rpm;
(4) Adding a polymerization system obtained by mixing 90 parts of acrylic acid with the neutralization degree reaching 95% and 70 parts of acrylamide into the step (3), and uniformly stirring at 8000 rpm;
(5) Stirring, heating to 68 ℃, adding 0.5 part of potassium persulfate for reaction, reacting at constant temperature for 100min, and crushing to obtain the water-absorbing and water-retaining resin.
Example 2
A preparation method of a super absorbent water-retaining resin comprises the following specific steps:
(1) Uniformly mixing 15 parts by weight of polyethylene glycol 2000, 1 part by weight of phosphorous acid, 0.01 part by weight of dibutyltin dilaurate and 7.5 parts by weight of hexamethylene diisocyanate, heating to 80 ℃ and reacting for 120min;
(2) 15 parts of acrylic acid-2-hydroxyethyl ester is added into the reaction system, and the reaction is continued for 1min to obtain a phosphorus-containing polyurethane surfactant;
(3) Cooling the prepared phosphorus-containing polyurethane surfactant to below 40 ℃, and rapidly stirring and dispersing under the condition of 8000 rpm;
(4) Adding a polymerization system obtained by mixing 100 parts of acrylic acid with the neutralization degree reaching 95% and 80 parts of acrylamide into the step (3), and uniformly stirring at 8000 rpm;
(5) Stirring, heating to 70 ℃, adding 1 part of potassium persulfate for reaction, reacting at constant temperature for 120min, and crushing to obtain the water-absorbing and water-retaining resin.
Example 3
A preparation method of a super absorbent water-retaining resin comprises the following specific steps:
(1) Uniformly mixing 20 parts by weight of polyethylene glycol 2000, 2 parts by weight of phosphorous acid, 0.05 part by weight of dibutyltin dilaurate and 10 parts by weight of hexamethylene diisocyanate, heating to 82 ℃ and reacting for 140min;
(2) Adding 20 parts of 2-hydroxyethyl acrylate into a reaction system, and continuously reacting for 1.5min to obtain a phosphorus-containing polyurethane surfactant;
(3) Cooling the prepared phosphorus-containing polyurethane surfactant to a temperature lower than 42 ℃, and rapidly stirring and dispersing under the condition of 8000 rpm;
(4) Adding a polymerization system obtained by mixing 110 parts of acrylic acid with 90 parts of acrylamide with the neutralization degree reaching 98% in the step (3), and uniformly stirring at 8000 rpm;
(5) Stirring, heating to 72 ℃, adding 1.5 parts of potassium persulfate for reaction, reacting at constant temperature for 140min, and crushing to obtain the water-absorbing and water-retaining resin.
Main reaction process
The molecular formula of the reaction process of the invention is shown as the following formula 1:
formula 1:
the invention connects phosphorus to the main chain of the polyamino acid surfactant, then connects hydroxyl-containing acrylic acid, finally further polymerizes with acrylic acid, acrylamide and the like to form polyurethane super absorbent water-retaining resin with phosphorus in the molecular main chain, and connects phosphorus element to the main chain of the water absorbent water-retaining resin molecule, so that the phosphorus element becomes a linking point on the main chain of the water absorbent water-retaining resin, the scale and corrosion inhibition effect of the resin is enhanced, and the water absorbent water-retaining performance and the reusability of the water absorbent resin are improved.
Experimental data
1. Water retention performance experiment:
and carrying out a water retention performance experiment on the resin added with the phosphorus-containing polyurethane surfactant. And (3) drying the resin with water absorption reaching a saturated state in a blast oven at 25 ℃, 30 ℃, 40 ℃ and 60 ℃ respectively, weighing once every 1 hour, recording the mass of the resin after water loss, and calculating the water retention rate.
As is clear from FIG. 1, the water retention property test was conducted at 25℃and 30℃and 40℃and 60℃and the water retention rate of the resin to which the phosphorus-containing urethane surfactant was added was higher than that of the polyurethane resin to which no phosphorus was added at the same temperature, and the difference was significantly increased with the lapse of time. The water content of the resin added with the phosphorus-containing polyurethane surfactant still keeps more than 30 percent after 12 hours under the same condition of 60 ℃, and the water retention rate of the polyurethane resin without the phosphorus is less than 25 percent.
2. The water absorption experiment was repeated:
the resin to which the phosphorus-containing polyurethane surfactant was added was subjected to repeated water absorption experiments. And (3) taking a certain mass of resin, soaking the resin in excessive deionized water until the resin is saturated with liquid absorption, measuring the water absorption, then putting the resin into a blast drying oven at 70 ℃ for drying to constant mass, measuring the water absorption again, and calculating the water absorption after each drying.
As can be seen from fig. 2, the repeated water absorption test is performed under the same condition, the repeated water absorption rate of the resin added with the phosphorus-containing polyurethane surfactant is higher than that of the polyurethane resin without phosphorus, when the repeated water absorption time reaches 15 times, the repeated water absorption rate of the resin without phosphorus is reduced to less than 10%, the repeated water absorption rate of the resin added with the phosphorus-containing polyurethane surfactant is also maintained to more than 60%, and the reduced rate is obviously lower than that of the resin without phosphorus, so that the resin with the phosphorus-containing polyurethane surfactant prepared by the invention has better repeated water absorption rate, and the service life can be prolonged.
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present invention are clearly and completely described, and it is obvious that the described embodiments are some embodiments of the present invention, but 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.
The foregoing is merely a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and variations may be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.
Claims (2)
1. A preparation method of a super absorbent water-retaining resin is characterized by comprising the following steps: the method comprises the following specific steps:
(1) Cooling the prepared phosphorus-containing polyurethane surfactant to 38-42 ℃, and rapidly stirring and dispersing under the condition of 8000 rpm; the phosphorus-containing polyurethane surfactant is prepared by mixing and reacting the following components in parts by weight: 10 to 20 parts of polyethylene glycol 2000, 0.5 to 2 parts of phosphorous acid, 0.01 to 0.1 part of dibutyltin dilaurate, 5 to 10 parts of hexamethylene diisocyanate and 10 to 20 parts of 2-hydroxyethyl acrylate; the preparation method of the phosphorus-containing polyurethane surfactant comprises the following steps:
(1) uniformly mixing polyethylene glycol 2000, phosphorous acid, dibutyl tin dilaurate and hexamethylene diisocyanate, heating to 80-82 ℃, and reacting for 100-140 min;
(2) adding acrylic acid-2-hydroxyethyl into the reaction system, and continuing to react for 0.5-1.5 min to obtain a phosphorus-containing polyurethane surfactant;
(2) Adding 90-110 parts by weight of acrylic acid and 70-90 parts by weight of an acrylamide polymerization system into the step (1), and uniformly stirring at 8000 rpm;
(3) Stirring, heating to 68-72 ℃, adding 0.5-1.5 parts of potassium persulfate for reaction, reacting at constant temperature for 100-140 min, and crushing to obtain the water-absorbing and water-retaining resin.
2. The method for preparing the super absorbent water-retaining resin according to claim 1, wherein the method comprises the following steps: the acrylic acid and acrylamide polymerization system is obtained by mixing acrylic acid and acrylamide with the neutralization degree reaching 95-98 percent.
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| CN116120689B (en) * | 2023-01-05 | 2024-04-09 | 万华化学集团股份有限公司 | Acrylic acid water-absorbent resin with low reverse osmosis and low extractable content and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH433739A (en) * | 1961-05-25 | 1967-04-15 | Bayer Ag | Process for the production of flame-retardant plastics |
| US4725629A (en) * | 1986-07-18 | 1988-02-16 | Kimberly-Clark Corporation | Process of making an interpenetrating superabsorbent polyurethane foam |
| WO1990006972A1 (en) * | 1988-12-15 | 1990-06-28 | Md Kasei Limited | Polyurethane molding having excellent resistance to water absorption |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH433739A (en) * | 1961-05-25 | 1967-04-15 | Bayer Ag | Process for the production of flame-retardant plastics |
| US4725629A (en) * | 1986-07-18 | 1988-02-16 | Kimberly-Clark Corporation | Process of making an interpenetrating superabsorbent polyurethane foam |
| WO1990006972A1 (en) * | 1988-12-15 | 1990-06-28 | Md Kasei Limited | Polyurethane molding having excellent resistance to water absorption |
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