CN1282659C - Preparation of acetate with high substitution and crystallation - Google Patents
Preparation of acetate with high substitution and crystallation Download PDFInfo
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- CN1282659C CN1282659C CN 200410027298 CN200410027298A CN1282659C CN 1282659 C CN1282659 C CN 1282659C CN 200410027298 CN200410027298 CN 200410027298 CN 200410027298 A CN200410027298 A CN 200410027298A CN 1282659 C CN1282659 C CN 1282659C
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- cellulose
- acid
- dispersion medium
- crystallinity
- microcrystalline cellulose
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- 238000006467 substitution reaction Methods 0.000 title claims abstract description 16
- 238000002360 preparation method Methods 0.000 title description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 title 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims abstract description 42
- 229920002301 cellulose acetate Polymers 0.000 claims abstract description 31
- 229920000168 Microcrystalline cellulose Polymers 0.000 claims abstract description 17
- 238000000034 method Methods 0.000 claims abstract description 17
- 235000019813 microcrystalline cellulose Nutrition 0.000 claims abstract description 17
- 239000008108 microcrystalline cellulose Substances 0.000 claims abstract description 17
- 229940016286 microcrystalline cellulose Drugs 0.000 claims abstract description 17
- 239000002612 dispersion medium Substances 0.000 claims abstract description 11
- 238000004821 distillation Methods 0.000 claims abstract description 11
- 239000007788 liquid Substances 0.000 claims abstract description 11
- 238000005406 washing Methods 0.000 claims abstract description 10
- 239000003054 catalyst Substances 0.000 claims abstract description 6
- 238000001035 drying Methods 0.000 claims abstract description 3
- 229940081735 acetylcellulose Drugs 0.000 claims description 27
- SMEGJBVQLJJKKX-HOTMZDKISA-N [(2R,3S,4S,5R,6R)-5-acetyloxy-3,4,6-trihydroxyoxan-2-yl]methyl acetate Chemical compound CC(=O)OC[C@@H]1[C@H]([C@@H]([C@H]([C@@H](O1)O)OC(=O)C)O)O SMEGJBVQLJJKKX-HOTMZDKISA-N 0.000 claims description 26
- 238000006243 chemical reaction Methods 0.000 claims description 16
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 claims description 13
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 12
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 10
- 230000004048 modification Effects 0.000 claims description 10
- 238000012986 modification Methods 0.000 claims description 10
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 8
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 claims description 8
- UOCLXMDMGBRAIB-UHFFFAOYSA-N 1,1,1-trichloroethane Chemical compound CC(Cl)(Cl)Cl UOCLXMDMGBRAIB-UHFFFAOYSA-N 0.000 claims description 6
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 6
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 6
- 230000032050 esterification Effects 0.000 claims description 6
- 238000005886 esterification reaction Methods 0.000 claims description 6
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims description 4
- AFVFQIVMOAPDHO-UHFFFAOYSA-N Methanesulfonic acid Chemical compound CS(O)(=O)=O AFVFQIVMOAPDHO-UHFFFAOYSA-N 0.000 claims description 3
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 3
- WSLDOOZREJYCGB-UHFFFAOYSA-N 1,2-Dichloroethane Chemical compound ClCCCl WSLDOOZREJYCGB-UHFFFAOYSA-N 0.000 claims description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 claims description 2
- 239000002253 acid Substances 0.000 claims description 2
- 229960001701 chloroform Drugs 0.000 claims description 2
- 239000006185 dispersion Substances 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 239000008096 xylene Substances 0.000 claims description 2
- 239000004033 plastic Substances 0.000 abstract description 5
- 229920003023 plastic Polymers 0.000 abstract description 5
- 238000001914 filtration Methods 0.000 abstract description 3
- 239000000945 filler Substances 0.000 abstract description 2
- GUBGYTABKSRVRQ-UHFFFAOYSA-N 2-(hydroxymethyl)-6-[4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxane-3,4,5-triol Chemical compound OCC1OC(OC2C(O)C(O)C(O)OC2CO)C(O)C(O)C1O GUBGYTABKSRVRQ-UHFFFAOYSA-N 0.000 abstract 2
- 230000002411 adverse Effects 0.000 abstract 1
- 229960000583 acetic acid Drugs 0.000 description 10
- 238000003756 stirring Methods 0.000 description 6
- 238000004886 process control Methods 0.000 description 5
- 235000010980 cellulose Nutrition 0.000 description 4
- 229920002678 cellulose Polymers 0.000 description 4
- 239000001913 cellulose Substances 0.000 description 4
- 239000013081 microcrystal Substances 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000011175 product filtration Methods 0.000 description 4
- 239000012362 glacial acetic acid Substances 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 125000000218 acetic acid group Chemical group C(C)(=O)* 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 229920006238 degradable plastic Polymers 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005213 imbibition Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 239000002932 luster Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000001223 reverse osmosis Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- -1 stir Substances 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
Landscapes
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
The present invention relates to a method for preparing cellulose acetate of high substitutility and high substitution degree in a complete heterogeneous system. The crystallinity of cellulose acetate of high substitution degree, which is prepared by a common heterogeneous system and the solution process, is low, and thus, the strength and the heat stability are low. The method is adverse to the utilization of the cellulose acetate as plastic filler, and is used for preparing high-strength plastics. In the complete heterogeneous system, microcrystalline cellulose or superfine (nanometer) cellulose microcrystalline is deeply esterified and modified by acetic acid. Under the conditions of pressure reduction and distillation, the cellulose microcrystalline is deeply esterified and modified by the acetic acid in a liquid dispersion medium under the action of a catalyst, the product obtained through washing, filtration and drying has the advantages of high substitutility and high substitution degree, and compared with the strength and the heat stability of cellulose acetate of the same substitution degree, the strength and the heat stability are enhanced.
Description
Technical field
The present invention relates to a kind of method that under complete heterogeneous system, prepares the acetyl cellulose of high-crystallinity high substitution value.
Background technology
Acetyl cellulose is a white solid, is most widely used a kind of in the present compo.Have that pliable and tough, transparent, good luster, good toughness, melt fluidity are good, characteristics such as easy-formation processing and thermoplasticity.And having biodegradability, its biodegradability reduces gradually along with the increase of substitution value.So acetyl cellulose be widely used in making spray paint, coating, textile fibres, plastics, wrapping material, film and reverse osmosis membrane etc.
But at the acetyl cellulose that with the Glacial acetic acid is the degree of depth modification that makes in the solution process of thinner, because Glacial acetic acid is the good solvent of acetyl cellulose, therefore the acetyl cellulose that generates all is dissolved in the acetic acid gradually.After reaction finished, acetyl cellulose need be regenerated from system and recrystallize, causes its degree of crystallinity very low, and its intensity and thermostability are also lower.Under general heterogeneous system,, therefore, there are a large amount of acetic acid to be dispersed in the system to the final stage of reaction owing in reaction process, constantly there is acetic acid to generate.Thereby the acetyl cellulose that causes generating is dissolved in the system gradually, so the degree of crystallinity of the acetyl cellulose of the degree of depth modification of last gained is also lower, causes its intensity and thermostability also lower.
Therefore the degree of crystallinity of the acetyl cellulose of the high substitution value for preparing by general heterogeneous system and solution process is all very low, causes its intensity and thermostability lower.Be unfavorable for like this that acetyl cellulose is used as plastic filler and in order to the higher plastics of preparation intensity.
Summary of the invention
Because the degree of crystallinity of general degree of depth modification cellulose acetate is all very low, the objective of the invention is under complete heterogeneous system, Microcrystalline Cellulose or ultra-fine (nanometer) Microcrystalline Cellulose are carried out degree of depth acetic acid esterification modification, through washing, the resulting product of filtration and dry back, have the high-crystallinity high substitution value, its intensity and the more identical substitution value of thermostability acetyl cellulose increase.
Method provided by the invention adopts the acetyl cellulose of preparation degree of depth modification under heterogeneous system completely, because a large amount of acetic acid that reaction generates are taken out of, remaining acetic acid can only swelling and can not dissolve the acetyl cellulose segment of generation in the system, make its crystalline texture obtain maximum keeping, so the acetyl cellulose of the more general degree of depth modification of its degree of crystallinity has had large increase.This imbibition simultaneously helps the infiltration of diacetyl oxide again, impels reaction further to carry out.Therefore can obtain the very acetyl cellulose of high-crystallinity that has of degree of depth modification, thereby improve the intensity of acetyl cellulose, its thermostability also increases.
The acetyl cellulose size of particles that this method makes is between 6.5nm～100 μ m, this method is under the underpressure distillation condition, in liquid dispersion medium, under catalyst action, Microcrystalline Cellulose is carried out degree of depth acetic acid esterification modification, make through washing, filtration and drying, the volume ratio of used liquid dispersion medium and Microcrystalline Cellulose is 1: 10～1: 25, aceticanhydride consumption and Microcrystalline Cellulose quality amount ratio are 2: 1～8: 1, catalyzer and Microcrystalline Cellulose quality amount ratio are 0.5: 100～15: 100, and the temperature of reaction of acetic acid esterification is 30 ℃ ~ 80 ℃.Utilize vacuum pump to carry out underpressure distillation in the reaction process, its vacuum tightness changes according to used liquid dispersion medium.Liquid dispersion medium is the mixed dispersion liquid of one or more different proportionings in trichloromethane, methylene dichloride, trichloroethane, ethylene dichloride, benzene,toluene,xylene, the tetracol phenixin.Catalyst system therefor is the mixing acid of one or more different proportionings in methylsulphonic acid, sulfuric acid, perchloric acid, hydrochloric acid, phosphoric acid and the organic sulfonic acid.Described Microcrystalline Cellulose can also be a nano micro crystal cellulose.
This method has following characteristics:
1, the acetyl cellulose that makes not only has high substitution value, also has higher degree of crystallinity simultaneously.It is more complete that its cellulosic structure and crystal formation keep.
2, the intensity of the acetyl cellulose that makes under this system and thermostability also increase, and have biodegradable.Can be in order to the preparation degradable plastics.
3, product is insoluble to dispersion medium at last, is easy to obtain.
Embodiment 1:
Get Microcrystalline Cellulose 2.0g, median size is 100 μ m.Add the 30ml trichloroethane, stir, the mixed diacetyl oxide 10ml that adds, sulfuric acid 0.01g and a small amount of trichloroethane, underpressure distillation reaction 2 hours, whole process control temp is 35 ℃.Hypsokinesis goes out suspension in funnel, and washing is to neutral, and oven dry promptly obtains product.
Embodiment 2:
Get Microcrystalline Cellulose 2.0g, median size is 50 μ m.Add 20ml dimethylbenzene, stir, mix and add diacetyl oxide 4ml, phosphoric acid 0.05g and a small amount of dimethylbenzene, underpressure distillation reaction 2 hours, whole process control temp is 50 ℃.Hypsokinesis goes out suspension in funnel, and after the washing, oven dry promptly obtains product.
Embodiment 3:
Get Microcrystalline Cellulose 2.0g, median size is 20 μ m.Add dimethylbenzene 50ml, stir for some time, treat that nano micro crystal cellulose is dispersed in the dimethylbenzene after, add diacetyl oxide 8ml, sulfuric acid 0.12g.Controlled temperature is 40 ℃ in the reaction process, underpressure distillation reaction 2 hours.With the product filtration washing, oven dry promptly gets product.
Embodiment 4:
Get Microcrystalline Cellulose 2.0g, median size is 1 μ m.Add the 40ml trichloroethane, stir, mix and add diacetyl oxide 12ml, methylsulphonic acid 0.20g and a small amount of trichloroethane, underpressure distillation reaction 3 hours, whole process control temp is 80 ℃.With the product filtration washing, oven dry promptly gets product.
Embodiment 5:
Get nano micro crystal cellulose 2.0g, median size is 50nm.Add 40ml toluene, stir, mix and add diacetyl oxide 16ml, perchloric acid 0.30g and small amount of toluene, underpressure distillation reaction 3 hours, whole process control temp is 30 ℃.With the product filtration washing, oven dry promptly gets product.
Embodiment 6:
Get nano micro crystal cellulose 2.0g, median size is 10nm.Add the 40ml tetracol phenixin, stir, mix and add diacetyl oxide 10ml, the mixing solutions 0.15g of perchloric acid and hydrochloric acid and a small amount of tetracol phenixin, underpressure distillation reaction 3 hours, whole process control temp is 45 ℃.With the product filtration washing, oven dry promptly gets product.
Claims (4)
1, a kind of method for making of high substitution value high-crystallinity acetyl cellulose, this method is carried out degree of depth acetic acid esterification modification to Microcrystalline Cellulose under catalyst action in liquid dispersion medium, through washing, filter with drying and make, the acetyl cellulose size of particles that makes is between 6.5nm～100 μ m, the volume ratio of used dispersion medium and Microcrystalline Cellulose is 1: 10～1: 25, aceticanhydride consumption and Microcrystalline Cellulose quality amount ratio are 2: 1～8: 1, catalyzer and Microcrystalline Cellulose quality amount ratio are 0.5: 100～15: 100, the temperature of reaction of acetic acid esterification is 30 ℃～80 ℃, it is characterized in that this method is under the underpressure distillation condition, carries out degree of depth acetic acid esterification modification to Microcrystalline Cellulose in liquid dispersion medium under catalyst action.
2, the method for making according to the acetyl cellulose of the high-crystallinity high substitution value described in the claim 1 is characterized in that utilizing in the reaction process vacuum pump to carry out underpressure distillation, and its vacuum tightness changes according to used liquid dispersion medium.
3, method for making according to the acetyl cellulose of the high-crystallinity high substitution value described in the claim 1 is characterized in that liquid dispersion medium is the mixed dispersion liquid of one or more different proportionings in trichloromethane, methylene dichloride, trichloroethane, ethylene dichloride, benzene,toluene,xylene, the tetracol phenixin.
4, the method for making according to the acetyl cellulose of the high-crystallinity high substitution value described in the claim 1 is characterized in that catalyst system therefor is the mixing acid of one or more different proportionings in methylsulphonic acid, sulfuric acid, perchloric acid, hydrochloric acid, phosphoric acid or the organic sulfonic acid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200410027298 CN1282659C (en) | 2004-05-24 | 2004-05-24 | Preparation of acetate with high substitution and crystallation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200410027298 CN1282659C (en) | 2004-05-24 | 2004-05-24 | Preparation of acetate with high substitution and crystallation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1583796A CN1583796A (en) | 2005-02-23 |
| CN1282659C true CN1282659C (en) | 2006-11-01 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 200410027298 Expired - Fee Related CN1282659C (en) | 2004-05-24 | 2004-05-24 | Preparation of acetate with high substitution and crystallation |
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| Country | Link |
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| CN (1) | CN1282659C (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IL258157A (en) * | 2015-09-17 | 2018-05-31 | Melodea Ltd | Ncc films and products based thereon |
| US11905342B2 (en) | 2015-09-17 | 2024-02-20 | Melodea Ltd. | NCC films and products based thereon |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130096298A1 (en) * | 2011-10-14 | 2013-04-18 | Celanese Acetate Llc | Methods for Synthesizing Acylated Cellulose Through Instillation of an Acidic Catalyst |
| US20130096297A1 (en) * | 2011-10-14 | 2013-04-18 | Celanese Acetate Llc | Methods for Synthesizing Acylated Cellulose Through Instillation of an Acidic Catalyst |
| CN105131128A (en) * | 2015-09-24 | 2015-12-09 | 上海应用技术学院 | Method for efficiently preparing cellulose acetate through catalyzing waste biomass by organic solvents |
| CN106509985A (en) * | 2016-12-14 | 2017-03-22 | 郑州人造金刚石及制品工程技术研究中心有限公司 | Cigarette filter tip and preparation method thereof |
-
2004
- 2004-05-24 CN CN 200410027298 patent/CN1282659C/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IL258157A (en) * | 2015-09-17 | 2018-05-31 | Melodea Ltd | Ncc films and products based thereon |
| US11021546B2 (en) | 2015-09-17 | 2021-06-01 | Melodea Ltd. | NCC films and products based thereon |
| US11905342B2 (en) | 2015-09-17 | 2024-02-20 | Melodea Ltd. | NCC films and products based thereon |
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| Publication number | Publication date |
|---|---|
| CN1583796A (en) | 2005-02-23 |
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Assignee: Zhejiang Joinway Pharmaceutical Co., Ltd. Assignor: Guangzhou Inst. of Chemistry, Chinese Academy of Sciences Contract fulfillment period: 2007.11.20 to 2013.11.20 contract change Contract record no.: 2008330002086 Denomination of invention: Preparation of acetate with high substitution and crystallation Granted publication date: 20061101 License type: Exclusive license Record date: 20081118 |
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| LIC | Patent licence contract for exploitation submitted for record |
Free format text: EXCLUSIVE LICENSE; TIME LIMIT OF IMPLEMENTING CONTACT: 2007.11.20 TO 2013.11.20; CHANGE OF CONTRACT Name of requester: ZHEJIANG PROVINCE ZHONGWEI MEDICINE CO., LTD. Effective date: 20081118 |
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Granted publication date: 20061101 Termination date: 20140524 |