CN113461846A - Preparation method of ultra-high molecular weight polyacrylamide - Google Patents
Preparation method of ultra-high molecular weight polyacrylamide Download PDFInfo
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- CN113461846A CN113461846A CN202110716461.9A CN202110716461A CN113461846A CN 113461846 A CN113461846 A CN 113461846A CN 202110716461 A CN202110716461 A CN 202110716461A CN 113461846 A CN113461846 A CN 113461846A
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- polyacrylamide
- polymerization tank
- molecular weight
- polymerization
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- 229920002401 polyacrylamide Polymers 0.000 title claims abstract description 46
- 238000002360 preparation method Methods 0.000 title claims abstract description 19
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 45
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical group NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 claims abstract description 18
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000006243 chemical reaction Methods 0.000 claims abstract description 17
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims abstract description 14
- 239000002994 raw material Substances 0.000 claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000004202 carbamide Substances 0.000 claims abstract description 8
- 125000000129 anionic group Chemical group 0.000 claims abstract description 7
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 7
- 238000010926 purge Methods 0.000 claims abstract description 7
- 238000007789 sealing Methods 0.000 claims abstract description 7
- 239000008367 deionised water Substances 0.000 claims abstract description 6
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 6
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 5
- 239000006184 cosolvent Substances 0.000 claims abstract description 5
- 230000003301 hydrolyzing effect Effects 0.000 claims abstract description 5
- 238000001035 drying Methods 0.000 claims abstract description 4
- 230000001678 irradiating effect Effects 0.000 claims abstract description 4
- 230000035484 reaction time Effects 0.000 claims abstract description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- OZAIFHULBGXAKX-UHFFFAOYSA-N 2-(2-cyanopropan-2-yldiazenyl)-2-methylpropanenitrile Chemical group N#CC(C)(C)N=NC(C)(C)C#N OZAIFHULBGXAKX-UHFFFAOYSA-N 0.000 claims description 14
- 239000003999 initiator Substances 0.000 claims description 11
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical group [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 10
- 239000004280 Sodium formate Substances 0.000 claims description 5
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 5
- HLBBKKJFGFRGMU-UHFFFAOYSA-M sodium formate Chemical compound [Na+].[O-]C=O HLBBKKJFGFRGMU-UHFFFAOYSA-M 0.000 claims description 5
- 235000019254 sodium formate Nutrition 0.000 claims description 5
- 238000003756 stirring Methods 0.000 claims description 5
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 4
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 claims description 4
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 239000007787 solid Substances 0.000 claims description 3
- 150000008062 acetophenones Chemical class 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims 1
- 238000013329 compounding Methods 0.000 description 3
- 239000003513 alkali Substances 0.000 description 2
- 239000012752 auxiliary agent Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000012966 redox initiator Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 125000003368 amide group Chemical group 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000004566 building material Substances 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000006276 transfer reaction Methods 0.000 description 1
Classifications
-
- 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
- C08F120/00—Homopolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
- C08F120/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F120/52—Amides or imides
- C08F120/54—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
- C08F120/56—Acrylamide; Methacrylamide
-
- 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
- C08F2/00—Processes of polymerisation
- C08F2/46—Polymerisation initiated by wave energy or particle radiation
- C08F2/48—Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light
-
- 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
- C08F4/00—Polymerisation catalysts
- C08F4/04—Azo-compounds
Abstract
The invention provides a novel preparation method of ultra-high molecular weight polyacrylamide, which relates to the technical field of polyacrylamide preparation and is characterized in that: the preparation method comprises the following preparation steps: acrylamide monomer polymerization step: adding the following raw materials in parts by mass into a polymerization tank, adding 22-28 parts of anionic acrylamide, 68-75 parts of deionized water, 1.5-3 parts of a hydrolytic agent, 1-4 parts of a cosolvent and 0.3-0.5 part of urea; adjusting the pH value to 5.5-6.5, adjusting the temperature of the polymerization tank to 22-28 ℃, simultaneously adding 1-2.5 parts of photoinitiator, adding a sealing cover above the polymerization tank, and performing nitrogen purging in the polymerization tank; placing an ultraviolet lamp light source in the polymerization tank, irradiating by the ultraviolet lamp, and controlling the temperature in the polymerization tank to be 4-6 ℃ during reaction, wherein the reaction time is 1-1.5 h; and (3) granulating: and after the polymerization reaction is finished, drying, granulating and crushing to 80 meshes to obtain the polyacrylamide. The molecular weight of the polyacrylamide prepared by the method is more than 3000 ten thousand, and the technical problem of small molecular weight of polyacrylamide in the prior art is effectively solved.
Description
Technical Field
The invention relates to the technical field of polyacrylamide preparation, and particularly relates to a preparation method of ultra-high molecular weight polyacrylamide.
Background
Polyacrylamide (PAM) is a water-soluble linear high-molecular polymer prepared by free radical initiated polymerization of acrylamide monomer, and can be divided into four types of nonionic, anionic, cationic and amphoteric types according to its structure, and the polyacrylamide has good water solubility and very high chemical activity, and because its main chain has a large amount of amide groups and can be used to prepare modified substances with various structures, the polyacrylamide product has been widely used in the industries of paper making, ore dressing, oil extraction, metallurgy, building materials, water treatment and the like, and is called "all-industrial auxiliary agent". The main application fields of polyacrylamide in China are four fields of oil exploitation, mining, papermaking and water treatment, and especially increasingly strict regulations promote the continuous increase of the demand of polyacrylamide on the aspect of water treatment.
In the preparation of polyacrylamide in the prior art, after an assistant such as alkali is added into an acrylamide aqueous solution, a redox initiator is added at a low temperature to initiate a polymerization reaction, so as to prepare the polyacrylamide. Although the method is simple, the defects that the consumption rate of the initiator is too high, the monomer conversion rate is reduced and the reducing agent is easy to participate in the chain transfer reaction caused by the redox initiator cannot be overcome. Resulting in a decrease in the molecular weight of the polymer and difficulty in obtaining ultra-high molecular weight products.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a novel preparation method of polyacrylamide, which can improve the molecular weight of polyacrylamide.
The technical scheme adopted by the invention for solving the technical problems is as follows: a preparation method of ultra-high molecular weight polyacrylamide comprises the following preparation steps:
acrylamide monomer polymerization step: adding the following raw materials in parts by mass into a polymerization tank, adding 22-28 parts of anionic acrylamide and 68-75 parts of deionized water, starting stirring, and adding 1.5-3 parts of a hydrolytic agent, 1-4 parts of a cosolvent and 1-3 parts of urea;
wherein the hydrolytic agent is sodium carbonate or sodium hydroxide, and the cosolvent is any one of thiourea, urea, isopropanol and sodium formate;
adjusting pH to 6.5-7, adjusting the temperature of the polymerization tank to 4-6 ℃, and adding 1-2.5 parts of photoinitiator;
adding a sealing cover above the polymerization tank, carrying out nitrogen purging in the polymerization tank for more than 20min, and sealing after the nitrogen purging is finished;
placing an ultraviolet lamp light source in the polymerization tank, irradiating by the ultraviolet lamp, and controlling the temperature in the polymerization tank to be 4-6 ℃ during reaction, wherein the reaction time is 1-1.5 h;
and (3) granulating: and after the polymerization reaction is finished, drying and granulating the polyacrylamide, and simultaneously crushing the polyacrylamide into 20-80 meshes to obtain the polyacrylamide.
Preferably, the photoinitiator is any one of dialkoxyacetophenone or chlorinated acetophenone.
Preferably, the composition also comprises an azo initiator, wherein the azo initiator is azobisisobutyronitrile, and the azobisisobutyronitrile and the photoinitiator are compounded in equal proportion.
Preferably, the conductivity of the acrylamide monomer is less than or equal to 10us/cm, and the conversion rate of acrylonitrile is more than or equal to 90% when the acrylamide monomer is polymerized.
Preferably, the total weight of the single polymerization raw materials in the polymerization tank is 160-180 kg.
Preferably, the method further comprises the following post-treatment steps: and in the post-treatment step, 50 parts by mass of crushed polyacrylamide particles are put into a reaction tank, and simultaneously 1 plus or minus 0.5 part by mass of high-purity solid sodium hydroxide is added, the temperature is increased to 45-50 ℃, and the temperature is kept for 1.5 hours.
Compared with the prior art, the preparation process is changed, the alkali auxiliary agent is avoided, the ultraviolet light is used for initiating polymerization reaction, the polymerization is initiated at low temperature, the whole process is simple, and the molecular weight of the obtained polyacrylamide raw material is high.
Detailed Description
The present invention is further described below with reference to specific embodiments, and it should be noted that, without conflict, any combination between the embodiments or technical features described below may form a new embodiment.
The invention mainly aims to solve the problem that the molecular weight is small in the preparation of polyacrylamide in the prior art, and provides a novel preparation method which can effectively improve the molecular weight of the prepared polyacrylamide.
Example 1
The polyacrylamide is prepared in the following manner in the embodiment, and the preparation method comprises the following steps:
adding the following raw materials in parts by mass into a polymerization tank, adding 22 parts of anionic acrylamide and 68 parts of deionized water, starting stirring, and simultaneously adding 1.5 parts of sodium carbonate, 1 part of sodium formate and 0.3 part of urea;
adjusting the pH value to 6.5, adjusting the temperature of the polymerization tank to 6 ℃, and simultaneously adding 1 part of initiator, wherein the initiator is prepared by compounding dialkoxyacetophenone and azobisisobutyronitrile in equal proportion;
adding a sealing cover above the polymerization tank, carrying out nitrogen purging in the polymerization tank for more than 20min, and sealing after the nitrogen purging is finished;
placing an ultraviolet lamp light source in the polymerization tank, irradiating by the ultraviolet lamp, and controlling the temperature in the polymerization tank to be 5 ℃ during reaction, and reacting for 1 h;
and (3) granulating: and after the polymerization reaction is finished, drying and granulating the polyacrylamide, and simultaneously crushing the polyacrylamide into 80 meshes to obtain the polyacrylamide.
Post-treatment: and in the post-treatment step, 50 parts by mass of crushed polyacrylamide particles are put into a reaction tank, and simultaneously 1 plus or minus 0.5 part by mass of high-purity solid sodium hydroxide is added, the temperature is increased to 45-50 ℃, and the temperature is kept for 1.5 hours.
Wherein, the acrylamide monomer is optimized, the conductivity of the adopted acrylamide monomer is less than or equal to 10us/cm, and the conversion rate of acrylonitrile is more than or equal to 90 percent when the acrylamide monomer is polymerized.
Furthermore, the total weight of the single polymerization raw materials in the polymerization tank is 170Kg, and the polyacrylamide with the mass more than 170Kg in the single batch reaction can be reacted in batches, so that the polymerization reaction efficiency and the polymerization effect are both ensured.
Example 1 after the reaction was completed, the polyacrylamide was found to have a molecular weight of 3310 ten thousand.
Example 2
Example 2 differs from example 1 in the ratio of raw material addition
The raw material proportions in example 2 were: adding the following raw materials in parts by mass into a reaction tank, adding 25 parts of anionic acrylamide and 71.5 parts of deionized water, starting stirring, and simultaneously adding 2.25 parts of sodium carbonate, 2.5 parts of sodium formate and 0.4 part of urea
Adjusting pH to 6.5, adjusting the temperature of the polymerization tank to 6 ℃, and adding 1.75 parts of initiator, wherein the initiator is prepared by compounding dialkoxyacetophenone and azobisisobutyronitrile in equal proportion.
The remaining steps were the same as in example 1.
Example 2 after the reaction was completed, the polyacrylamide was found to have a molecular weight of 3218 ten thousand.
Example 3
Example 2 differs from example 1 in the ratio of raw material addition
The raw material proportions in example 2 were: adding the following raw materials in parts by mass into a reaction tank, adding 28 parts of anionic acrylamide and 75 parts of deionized water, starting stirring, and simultaneously adding 3 parts of sodium carbonate, 4 parts of sodium formate and 0.5 part of urea
Adjusting pH to 6.5, adjusting the temperature of the polymerization tank to 6 ℃, and adding 2.5 parts of initiator, wherein the initiator is prepared by compounding dialkoxyacetophenone and azobisisobutyronitrile in equal proportion.
Example 3 after the reaction was completed, the polyacrylamide was found to have a molecular weight of 3290 ten thousand.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.
Claims (6)
1. A preparation method of ultra-high molecular weight polyacrylamide is characterized by comprising the following steps: the preparation method comprises the following preparation steps:
acrylamide monomer polymerization step: adding the following raw materials in parts by mass into a polymerization tank, adding 22-28 parts of anionic acrylamide and 68-75 parts of deionized water, starting stirring, and adding 1.5-3 parts of a hydrolytic agent, 1-4 parts of a cosolvent and 1-3 parts of urea;
wherein the hydrolytic agent is sodium carbonate or sodium hydroxide, and the cosolvent is any one of thiourea, urea, isopropanol and sodium formate;
adjusting pH to 6.5-7, adjusting the temperature of the polymerization tank to 4-6 ℃, and adding 1-2.5 parts of photoinitiator;
adding a sealing cover above the polymerization tank, carrying out nitrogen purging in the polymerization tank for more than 20min, and sealing after the nitrogen purging is finished;
placing an ultraviolet lamp light source in the polymerization tank, irradiating by the ultraviolet lamp, and controlling the temperature in the polymerization tank to be 4-6 ℃ during reaction, wherein the reaction time is 1-1.5 h;
and (3) granulating: and after the polymerization reaction is finished, drying and granulating the polyacrylamide, and simultaneously crushing the polyacrylamide into 20-80 meshes to obtain the polyacrylamide.
2. The method for preparing ultra-high molecular weight polyacrylamide according to claim 1, wherein the method comprises the following steps: the photoinitiator is any one of dialkoxyacetophenone or chlorinated acetophenone.
3. The method for preparing ultra-high molecular weight polyacrylamide according to claim 2, wherein the method comprises the following steps: the composite material also comprises an azo initiator, wherein the azo initiator is azobisisobutyronitrile, and the azobisisobutyronitrile and the photoinitiator are compounded in equal proportion.
4. The method for preparing ultra-high molecular weight polyacrylamide according to claim 1, wherein the method comprises the following steps: the conductivity of the acrylamide monomer is less than or equal to 10us/cm, and the conversion rate of acrylonitrile is more than or equal to 90 percent when the acrylamide monomer is polymerized.
5. The method for preparing ultra-high molecular weight polyacrylamide according to claim 1, wherein the method comprises the following steps: the total weight of the single polymerization raw materials in the polymerization tank is 160-180 kg.
6. The method for preparing ultra-high molecular weight polyacrylamide according to claim 1, wherein the method comprises the following steps: further comprises the following post-treatment steps: and in the post-treatment step, 50 parts by mass of crushed polyacrylamide particles are put into a reaction tank, and simultaneously 1 plus or minus 0.5 part by mass of high-purity solid sodium hydroxide is added, the temperature is increased to 45-50 ℃, and the temperature is kept for 1.5 hours.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110716461.9A CN113461846A (en) | 2021-06-28 | 2021-06-28 | Preparation method of ultra-high molecular weight polyacrylamide |
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| CN202110716461.9A CN113461846A (en) | 2021-06-28 | 2021-06-28 | Preparation method of ultra-high molecular weight polyacrylamide |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101353392A (en) * | 2007-07-27 | 2009-01-28 | 朱定洋 | Preparation of high molecular weight instant cation polyacrylamide |
| CN102731699A (en) * | 2011-04-01 | 2012-10-17 | 中国石油化工股份有限公司 | Preparation method of ultra high molecular weight anionic polyacrylamide |
| CN107337753A (en) * | 2017-06-22 | 2017-11-10 | 罗山县中原聚合物有限公司 | High molecular anion type polycrylamide and preparation method and application |
| CN109705265A (en) * | 2019-01-02 | 2019-05-03 | 江苏富淼科技股份有限公司 | A kind of initiation method for polymerization of aqueous solution of acrylamide |
| CN109721681A (en) * | 2017-10-31 | 2019-05-07 | 扬州科苑化工有限公司 | Instant polymeric anion type polyacrylamide |
-
2021
- 2021-06-28 CN CN202110716461.9A patent/CN113461846A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101353392A (en) * | 2007-07-27 | 2009-01-28 | 朱定洋 | Preparation of high molecular weight instant cation polyacrylamide |
| CN102731699A (en) * | 2011-04-01 | 2012-10-17 | 中国石油化工股份有限公司 | Preparation method of ultra high molecular weight anionic polyacrylamide |
| CN107337753A (en) * | 2017-06-22 | 2017-11-10 | 罗山县中原聚合物有限公司 | High molecular anion type polycrylamide and preparation method and application |
| CN109721681A (en) * | 2017-10-31 | 2019-05-07 | 扬州科苑化工有限公司 | Instant polymeric anion type polyacrylamide |
| CN109705265A (en) * | 2019-01-02 | 2019-05-03 | 江苏富淼科技股份有限公司 | A kind of initiation method for polymerization of aqueous solution of acrylamide |
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Application publication date: 20211001 |
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