CN115109301A - Preparation method of hollow open cellulose diacetate microspheres - Google Patents
Preparation method of hollow open cellulose diacetate microspheres Download PDFInfo
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- CN115109301A CN115109301A CN202110292955.9A CN202110292955A CN115109301A CN 115109301 A CN115109301 A CN 115109301A CN 202110292955 A CN202110292955 A CN 202110292955A CN 115109301 A CN115109301 A CN 115109301A
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- cellulose diacetate
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- 229920001747 Cellulose diacetate Polymers 0.000 title claims abstract description 53
- 239000004005 microsphere Substances 0.000 title claims abstract description 27
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000000839 emulsion Substances 0.000 claims abstract description 15
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 claims abstract description 9
- 239000007864 aqueous solution Substances 0.000 claims abstract description 9
- 238000010438 heat treatment Methods 0.000 claims abstract description 9
- 239000003431 cross linking reagent Substances 0.000 claims abstract description 6
- 238000001914 filtration Methods 0.000 claims abstract description 6
- 238000005406 washing Methods 0.000 claims abstract description 6
- 239000000203 mixture Substances 0.000 claims abstract description 5
- 239000004094 surface-active agent Substances 0.000 claims abstract description 5
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 30
- 238000003756 stirring Methods 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 239000000243 solution Substances 0.000 claims description 8
- NWGKJDSIEKMTRX-AAZCQSIUSA-N Sorbitan monooleate Chemical compound CCCCCCCC\C=C/CCCCCCCC(=O)OC[C@@H](O)[C@H]1OC[C@H](O)[C@H]1O NWGKJDSIEKMTRX-AAZCQSIUSA-N 0.000 claims description 4
- KXBFLNPZHXDQLV-UHFFFAOYSA-N [cyclohexyl(diisocyanato)methyl]cyclohexane Chemical compound C1CCCCC1C(N=C=O)(N=C=O)C1CCCCC1 KXBFLNPZHXDQLV-UHFFFAOYSA-N 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 3
- WUKNPIYSKBLCQI-UHFFFAOYSA-N CC(C=C1)=CC=C1C1=CC=C(C)C=C1.N=C=O.N=C=O Chemical compound CC(C=C1)=CC=C1C1=CC=C(C)C=C1.N=C=O.N=C=O WUKNPIYSKBLCQI-UHFFFAOYSA-N 0.000 claims 1
- 239000005057 Hexamethylene diisocyanate Substances 0.000 claims 1
- RCEAADKTGXTDOA-UHFFFAOYSA-N OS(O)(=O)=O.CCCCCCCCCCCC[Na] Chemical compound OS(O)(=O)=O.CCCCCCCCCCCC[Na] RCEAADKTGXTDOA-UHFFFAOYSA-N 0.000 claims 1
- PRXRUNOAOLTIEF-ADSICKODSA-N Sorbitan trioleate Chemical compound CCCCCCCC\C=C/CCCCCCCC(=O)OC[C@@H](OC(=O)CCCCCCC\C=C/CCCCCCCC)[C@H]1OC[C@H](O)[C@H]1OC(=O)CCCCCCC\C=C/CCCCCCCC PRXRUNOAOLTIEF-ADSICKODSA-N 0.000 claims 1
- 125000000218 acetic acid group Chemical group C(C)(=O)* 0.000 claims 1
- RRAMGCGOFNQTLD-UHFFFAOYSA-N hexamethylene diisocyanate Chemical compound O=C=NCCCCCCN=C=O RRAMGCGOFNQTLD-UHFFFAOYSA-N 0.000 claims 1
- 239000011259 mixed solution Substances 0.000 claims 1
- 238000004945 emulsification Methods 0.000 abstract description 2
- 238000001704 evaporation Methods 0.000 abstract description 2
- 239000003960 organic solvent Substances 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract description 2
- 229920000875 Dissolving pulp Polymers 0.000 abstract 1
- 239000000463 material Substances 0.000 description 7
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 229920002678 cellulose Polymers 0.000 description 3
- 239000001913 cellulose Substances 0.000 description 3
- 239000008367 deionised water Substances 0.000 description 3
- 229910021641 deionized water Inorganic materials 0.000 description 3
- 229920002301 cellulose acetate Polymers 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 238000000935 solvent evaporation Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
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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
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/28—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
- C08J9/286—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum the liquid phase being a solvent for the monomers but not for the resulting macromolecular composition, i.e. macroporous or macroreticular polymers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2301/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
- C08J2301/08—Cellulose derivatives
- C08J2301/10—Esters of organic acids
- C08J2301/12—Cellulose acetate
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Manufacturing Of Micro-Capsules (AREA)
Abstract
The invention provides a cellulose diacetate microsphere with a hollow opening shape and a preparation method thereof. Dissolving cellulose diacetate as a main raw material in an organic solvent, adding dichloromethane and a surfactant, uniformly mixing, then dropwise adding the mixture into a sodium dodecyl sulfate aqueous solution for emulsification, heating for a short time, evaporating dichloromethane, adding a cross-linking agent to solidify the cellulose diacetate when a bubble-droplet connection structure is formed by a cellulose diacetate emulsion, and filtering and washing to obtain the cellulose diacetate microspheres with hollow open morphology. By adopting the technical means of the invention, the hollow volume and the opening size of the microsphere can be purposefully controlled, and the invention provides a new thought for the structure regulation of the cellulose diacetate microsphere.
Description
Technical Field
The invention relates to the field of cellulose diacetate materials, in particular to a preparation method of hollow cellulose diacetate microspheres.
Background
The cellulose diacetate industry in China started in the fifties of the last century, and the development of the cellulose diacetate industry enters the stage of accelerating growth due to the pulling of the requirements of various industries in China in recent years, but the overall development scale is still small. Cellulose acetate is one of the common derivatives of cellulose, and is a cellulose derivative produced by converting cellulose with acetic acid, and has been commercialized at the earliest. The cellulose diacetate as the base material has the advantages of wide source, low cost and mature process, and the material characteristics of the cellulose diacetate comprise transparency, glossiness, toughness, nonflammability, innocuity and harmlessness, thereby having important application in the fields of paper industry, textile industry and the like.
Based on the excellent characteristics of the cellulose diacetate, the development of high value-added products from the cellulose diacetate as a raw material is paid attention by many researchers, and the material prepared from the cellulose diacetate as a matrix shows excellent development prospects in the fields of mechanics, thermal, electrochemistry, material science and the like.
Cellulose diacetate is easy to dissolve in various organic solvents, cellulose diacetate microspheres can be prepared by an emulsification method, and the size and the pore structure of the microspheres can be designed and regulated differently according to the requirements of users so as to meet the use characteristics of the material, including drug slow release, adsorption of heavy metals, proteins and other substances. The invention relates to a preparation method of a novel cellulose diacetate microsphere with a mesopore opening shape. The method forms a hollow open structure by cross-linking cellulose acetate during solvent evaporation.
Disclosure of Invention
The invention aims to provide a preparation method of cellulose diacetate microspheres with hollow opening shapes. The method not only provides a new idea for the structure design of the cellulose diacetate material, but also provides a new path for the design and production of high value-added products of the cellulose diacetate.
The hollow open cellulose diacetate microspheres of the invention have a size of 8-10 microns and an opening size of 3-5 microns.
The preparation method of the hollow open cellulose diacetate microspheres comprises the following steps:
(1) cellulose diacetate was dissolved in N, N-dimethylformamide. Adding dichloromethane after dissolving, stirring to form a uniform solution, adding a surfactant, and stirring uniformly;
(2) dropwise adding the uniform liquid prepared in the step (1) into an aqueous solution of sodium dodecyl sulfate, and stirring to prepare a cellulose diacetate emulsion;
(3) and (3) heating the emulsion obtained in the step (2) in a water bath for a short time, adding a cross-linking agent, stirring, filtering and washing to obtain the hollow cellulose diacetate microspheres with the open morphology.
Furthermore, the concentration of the N, N-dimethylformamide solution of the cellulose diacetate is 5-10%, the dissolving temperature is 50-80 ℃, the volume of the added dichloromethane is 2-4 times of the volume of the N, N-dimethylformamide, the stirring speed is 300-500 rpm, and the mass of the added surfactant is 1-4 times of the mass of the cellulose diacetate.
Further, the liquid volume in the step (2) is 0.1-0.2 time of the volume of the sodium dodecyl sulfate aqueous solution in the step (1), the mass concentration of the sodium dodecyl sulfate is between 1% -2%, and the stirring speed is between 300 and 500 rpm.
Further, the heating time in the step (3) is controlled to be 1-3 min, and the water bath temperature is controlled to be 80-100 ℃. The volume ratio of the added cross-linking agent to the solution in the step (3) is 1: (50-100).
The key points of the invention are as follows:
the dichloromethane can evaporate at the temperature of more than 40 ℃, the cellulose diacetate emulsion can form a certain 'bubble-emulsion' connection structure, the cellulose diacetate is crosslinked at the moment, the cellulose diacetate microspheres with hollow opening shapes can be obtained, and the structure can adjust the opening size and the hollow volume size of the microspheres by controlling the evaporation speed.
Drawings
FIG. 1 shows a "bubble-emulsion" connection structure of a cellulose diacetate emulsion obtained in step 3 of example 1 of the present invention.
FIG. 2 is a scanning electron micrograph of cellulose diacetate microspheres with a controlled morphology of openings obtained in example 1 of the present invention.
Detailed Description
Example 1
2 g of cellulose diacetate was dissolved in 20 mL of N, N-dimethylformamide at 60 ℃ to give a clear solution, 80 mL of dichloromethane was added and stirred well, and then 3 g of span 80 was added and stirred well. Dropwise adding 10 mL of the mixture into 100 mL of aqueous solution containing 1% of sodium dodecyl sulfate by mass, and stirring at 600 rpm for 3 min to obtain uniform emulsion of cellulose diacetate; and then heating the emulsion for 1 min in a water bath at the temperature of 80 ℃, adding 2 mL of dicyclohexylmethane diisocyanate, quickly stirring for 30 s, filtering, and washing with deionized water to obtain the cellulose diacetate microspheres with hollow open morphology.
Example 2
1 g of cellulose diacetate was dissolved in 20 mL of N, N-dimethylformamide at 60 ℃ to form a clear solution, 40 mL of dichloromethane was added and stirred well, followed by 2 g of span 80 and stirred well. Dropwise adding 10 mL of the mixture into 50 mL of aqueous solution containing 1% of sodium dodecyl sulfate by mass, and stirring at 600 rpm for 3 min to obtain uniform emulsion of cellulose diacetate; and then heating the emulsion for 1 min in a water bath at the temperature of 80 ℃, adding 1 mL of dicyclohexylmethane diisocyanate, quickly stirring for 30 s, filtering, and washing with deionized water to obtain the cellulose diacetate microspheres with hollow open morphology.
Example 3
20 g of cellulose diacetate was dissolved in 200 mL of N, N-dimethylformamide at 60 ℃ to form a clear solution, 800 mL of methylene chloride was added and stirred well, followed by 30 g of span 80 and stirred well. Dropwise adding 100 mL of the mixture into 1000 mL of aqueous solution containing 1% of sodium dodecyl sulfate by mass, and stirring at 800 rpm for 5 min to obtain uniform emulsion of cellulose diacetate; and heating the emulsion in a water bath at 80 ℃ for 2 min, adding 20 mL dicyclohexylmethane diisocyanate, quickly stirring for 1 min, filtering, and washing with deionized water to obtain the hollow cellulose diacetate microspheres with an open morphology.
Claims (6)
1. A cellulose diacetate microsphere with a hollow opening morphology is characterized in that: the structure of the microsphere is hollow and is provided with an open type macropore.
2. The method for preparing hollow cellulose diacetate microspheres with an open morphology as claimed in claim 1, wherein the method comprises the following steps: the preparation method comprises the following steps: (1) cellulose diacetate was dissolved in N, N-dimethylformamide.
3. Adding dichloromethane after dissolving, stirring to form a uniform solution, adding a surfactant, and stirring uniformly; (2) dropwise adding the uniform liquid prepared in the step (1) into an aqueous solution of sodium dodecyl sulfate, and stirring to prepare a cellulose diacetate emulsion; (3) and (3) heating the emulsion obtained in the step (2) in a water bath for a short time, adding a cross-linking agent, stirring, filtering and washing to obtain the hollow cellulose diacetate microspheres with the open morphology.
4. The method for preparing hollow cellulose diacetate microspheres with open morphology according to claim 2, wherein the method comprises the following steps: the acetyl degree of the cellulose diacetate used in the step (1) is between 2.0 and 2.7; the concentration of the N, N-dimethylformamide soluble in the N, N-dimethylformamide is between 5 and 10 percent; the volume of the added dichloromethane is 2 to 4 times of the volume of the N, N-dimethylformamide; adding surfactant span 80 or span 85 or their mixture in an amount of 1-4 times of the mass of cellulose diacetate.
5. The method for preparing hollow cellulose diacetate microspheres with open morphology according to claim 2, wherein the method comprises the following steps: the mass concentration of the sodium dodecyl sulfate aqueous solution used in the step (2) is between 1 and 2 percent; the adding amount of the solution obtained in the step (1) is 0.1-0.2 times of the volume of the lauryl sodium sulfate aqueous solution.
6. The method for preparing hollow cellulose diacetate microspheres with open morphology according to claim 2, wherein the method comprises the following steps: in the step (3), the heating temperature of the water bath is between 50 and 80 ℃; heating for 1-3 min; the amount of the added cross-linking agent is 0.02-0.01 times of the volume of the mixed solution in the step (3), and the cross-linking agent is any one or any one of dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, 4' -diphenylmethane diisocyanate and dimethylbiphenyl diisocyanate.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110292955.9A CN115109301A (en) | 2021-03-18 | 2021-03-18 | Preparation method of hollow open cellulose diacetate microspheres |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110292955.9A CN115109301A (en) | 2021-03-18 | 2021-03-18 | Preparation method of hollow open cellulose diacetate microspheres |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0842657A1 (en) * | 1996-11-19 | 1998-05-20 | OctoPlus B.V. | Microspheres for controlled release and processes to prepare these microspheres |
| CN1579599A (en) * | 2003-08-01 | 2005-02-16 | 中国科学院大连化学物理研究所 | Charged microporous filtration membrane and affinity base membrane preparing method |
| CN102911379A (en) * | 2011-08-04 | 2013-02-06 | 南通醋酸纤维有限公司 | Method for preparing cellulose acetate microspheres and product prepared by method |
| CN103724635A (en) * | 2013-12-06 | 2014-04-16 | 中国烟草总公司郑州烟草研究院 | Preparation method for cellulose acetate porous microspheres and product applying preparation method |
| CN108745219A (en) * | 2018-06-20 | 2018-11-06 | 四川大学 | A kind of cellulose microsphere preparation method of novel high intensity and even intensity |
| CN111454468A (en) * | 2020-03-27 | 2020-07-28 | 西安交通大学 | Shape-controllable intelligent response microsphere and preparation method thereof |
| CN115109300A (en) * | 2021-03-17 | 2022-09-27 | 四川大学 | Preparation method of macroporous cellulose diacetate microspheres |
-
2021
- 2021-03-18 CN CN202110292955.9A patent/CN115109301A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0842657A1 (en) * | 1996-11-19 | 1998-05-20 | OctoPlus B.V. | Microspheres for controlled release and processes to prepare these microspheres |
| CN1579599A (en) * | 2003-08-01 | 2005-02-16 | 中国科学院大连化学物理研究所 | Charged microporous filtration membrane and affinity base membrane preparing method |
| CN102911379A (en) * | 2011-08-04 | 2013-02-06 | 南通醋酸纤维有限公司 | Method for preparing cellulose acetate microspheres and product prepared by method |
| WO2013016982A1 (en) * | 2011-08-04 | 2013-02-07 | 南通醋酸纤维有限公司 | Cellulose acetate microsphere preparation method and product prepared thereby |
| CN103724635A (en) * | 2013-12-06 | 2014-04-16 | 中国烟草总公司郑州烟草研究院 | Preparation method for cellulose acetate porous microspheres and product applying preparation method |
| CN108745219A (en) * | 2018-06-20 | 2018-11-06 | 四川大学 | A kind of cellulose microsphere preparation method of novel high intensity and even intensity |
| CN111454468A (en) * | 2020-03-27 | 2020-07-28 | 西安交通大学 | Shape-controllable intelligent response microsphere and preparation method thereof |
| CN115109300A (en) * | 2021-03-17 | 2022-09-27 | 四川大学 | Preparation method of macroporous cellulose diacetate microspheres |
Non-Patent Citations (1)
| Title |
|---|
| 曾丹林;陈诗渊;张崎;刘胜兰;: "纤维素制备微球材料的研究进展" * |
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Application publication date: 20220927 |