CN102702363A - Preparation method of hydroxypropyl methylcellulose acetate succinate in novel solvent system - Google Patents
Preparation method of hydroxypropyl methylcellulose acetate succinate in novel solvent system Download PDFInfo
- Publication number
- CN102702363A CN102702363A CN2012101784407A CN201210178440A CN102702363A CN 102702363 A CN102702363 A CN 102702363A CN 2012101784407 A CN2012101784407 A CN 2012101784407A CN 201210178440 A CN201210178440 A CN 201210178440A CN 102702363 A CN102702363 A CN 102702363A
- Authority
- CN
- China
- Prior art keywords
- preparation
- esterification
- product
- vltra tears
- hydroxypropyl methylcellulose
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Abstract
The invention discloses a preparation method of hydroxypropyl methylcellulose acetate succinate in a novel solvent system. The preparation method comprises the steps as follows: adding hydroxypropyl methylcellulose, inert solvents, esterifying agents and catalyzers into a reaction vessel, and heating and stirring for esterification; lowering the temperature to the room temperature after esterification, and adding precipitants for settling out products; washing the products, and distilling to separate the inert solvents, thereby obtaining hydroxypropyl methylcellulose acetate succinate. According to the invention, the preparation method has the advantages that the reaction condition is mild, the reaction rate is high, the solvents can be recovered, and the post processing for the products is simple.
Description
Technical field
The invention belongs to the synthetic field of cellulose ether-esters, the preparation method of hydroxypropyl methyl cellulose succinate under particularly a kind of novel dissolvent system.
Background technology
Hydroxypropyl methylcellulose acetate succinate is white to flaxen powder or a particle, and true density is 1.27-1.30g/cm
3, be soluble in the mixed solvent of acetone, methyl alcohol, ethanol-ethylene dichloride, alcohol-water, be insoluble to ether and water.
Hydroxypropyl methylcellulose acetate succinate is a kind of mixing dibasic acid esters of non-ionic celluloses ether class; Wherein contain propoxyl, methoxyl group, ethanoyl, 4 groups of succinyl, so its character presents different solubility properties with the difference of group content.Propoxyl is a kind of hydrophilic radical, and it is water-soluble that its existence has this cellulose ether-esters; Methoxyl group is a kind of hydrophobic group, and its existence makes it dissolve in certain organic solvent, helps the preparation of coating membrance; An amount of ethanoyl increases the coating membrance snappiness, but solvability reduces; And the existence of succinyl can improve the solvability of film, but acid resistance, water tolerance descend.
Therefore, acetic acid hydroxypropyl methyl cellulose hemisuccinate ester has purposes very widely.Its most important purposes is that itself has plasticity-as the enteric coatings material, and film forming properties is good; Characteristics such as dissolution rate is fast; A spot of softening agent just can improve the dressing film strength, improves the exterior appearance of medicament, has therefore also reduced the harm that softening agent produces human body.And the gentle control of the slow control reagent micropill that it can also prepare medicine plays very important effect for the target location release of medicine, owing to itself inherent radical species, makes it good at small intestine epimere solubility property, has increased medicine and must absorb at little intestinal segment.In recent years, also used it for aspects such as solid macromolecule carrier, slow controlled release matrix, it is occupied an important position in auxiliary material.
At present, no matter the method for domestic and international acetic acid synthesized hydroxypropyl methyl cellulose succinate is to adopt one feeding method or the reaction of secondary batching method, mainly is that employing is a medium with acetic acid, and sodium-acetate is the reaction system of catalyzer.Being operating as of one feeding method reaction: at first join raw material Vltra tears, solvent acetic acid, esterifying agent diacetyl oxide and succinyl oxide, catalyst acetic acid sodium in the reaction vessel simultaneously; This mixture adds a large amount of water and makes the complete precipitating of product behind reaction 2-10h under the 60-110 ℃ of condition, repeatedly washing; Normal pressure filters; Till being neutrality to elutant, product is dry, can obtain hydroxypropyl methylcellulose acetate succinate.When the secondary batching legal system is equipped with cellulose ether-esters, earlier derivatived cellulose is reacted for some time in acetum, make the derivatived cellulose dissolving or be dispersed in the solution; So that the reactive group on the activation fiber element adds catalyzer and esterifying agent then, keep this temperature and react; After for some time; Finish reaction with deionized water, product can obtain title product through precipitating, filtration, repeatedly washing, drying.
But, in process of industrialization, use original system to exist many drawbacks, as strong to equipment corrosion, solvent can not be recycled, and residual acetic acid makes shortcomings such as product stock degradation.And product is more loaded down with trivial details in post-processing stages, need wash just with a large amount of water to reach requirement, product also can occur by the phenomenon of acetic acid embedding simultaneously, has had a strong impact on the quality and the performance of product.
Summary of the invention
The objective of the invention is to overcome in the prior art the above-mentioned shortcoming of using acetate system to exist, the preparation method of hydroxypropyl methylcellulose acetate succinate under a kind of feasible novel dissolvent system is provided for suitability for industrialized production.The present invention selects new organic reaction solvent system for use, and promptly adopting acetone is medium, and the 4-Dimethylamino pyridine is that catalyzer reacts, and after the end, product postprocessing is simple.Method of the present invention is simpler and more cheap than ordinary method, through new reaction system, the residual acetic acid amount of product is reduced, and organic solvent can reclaim; Practiced thrift cost, simultaneously, it is few also to have a catalyst levels, and reaction conditions is gentle; Reaction times is short, and yield is high, the advantage that side reaction is few.
For realizing above-mentioned purpose, a plurality of technical schemes provided by the invention are following.
The preparation method of hydroxypropyl methylcellulose acetate succinate under the novel dissolvent system comprises following operation steps:
(1) esterification: Vltra tears, inert solvent, esterifying agent, catalyzer are joined in the reaction vessel, and heated and stirred is carried out esterification;
(2) product extracts: after esterification finishes, be cooled to normal temperature after, add precipitation agent, make the product precipitating, washed product, the fractionation by distillation inert solvent obtains hydroxypropyl methylcellulose acetate succinate.
Preferably, inert solvent is a hydrophilic organic solvent-acetone, 1 described in the step (1), the 4-dioxane, and more than one in the N, the amount ratio of said inert solvent and Vltra tears are 4-50 mL/g.
Preferably, the described esterifying agent of step (1) is a diacetyl oxide
WithSuccinic anhydried, said diacetyl oxide and Vltra tears amount ratio are mL/g for 0.3-30 unit, said diacetyl oxide and Vltra tears weight ratio are 0.3-30.
Preferably, the said diacetyl oxide of step (1)
WithSuccinic anhydried adds or adds earlier wherein a kind of participation reaction simultaneously, and then adds a kind of in addition.
Preferably, the described catalyzer of step (1) does
, R wherein
1And R
2Be C
nH
2n+1, n=is a positive integer, consumption is 0.01 ~ 5 times of Vltra tears quality.
Preferably, said n=1, promptly said catalyzer is the 4-Dimethylamino pyridine.
Preferably, the temperature of the said esterification of step (1) is 50-130 ℃, and the reaction times is 2-24h, and pressure is 1-10bar.
Preferably, the said reaction vessel of step (1) is autoclave or there-necked flask.
Preferably, the described precipitation agent of step (2) is deionized water, Hydrogen chloride or dilute sulphuric acid, and the amount ratio of precipitation agent and said esterification products is 20-1000 mL/g.
Preferably, deionized water or boiling water are adopted in the said washing of step (2).
Preferably, the described washing solvent for use of step (2) is a deionized water, and the temperature of bath water is 85-100 ℃.
Compared with prior art; The present invention has following beneficial effect: the present invention adopts novel dissolvent systems such as acetone; The 4-Dimethylamino pyridine is the method for Preparation of Catalyst hydroxypropyl methylcellulose acetate succinate, can reduce required temperature of reaction and the time that shortens reaction; Esterification is stable, and side reaction is few, and catalyst levels is few; Temperature of reaction is low, and the reaction times is short, and the reaction product aftertreatment is simple, and residual acetic acid content is less; In the production process, energy consumption is low, and the recyclable utilization of solvent reduces equipment corrosion, and comprehensive cost is low, meets the direction of energy-saving and emission-reduction.
Description of drawings
Fig. 1 is the infrared spectrogram (acetyl content 8.2%, succinyl content 12.5%) of hydroxypropyl methylcellulose acetate succinate.
Embodiment
Below in conjunction with embodiment the present invention is done further detailed description, but embodiment of the present invention is not limited thereto.
Embodiment 1
(1) esterification: in autoclave, add raw material Vltra tears 10g; Solvent acetone 80mL; Esterifying agent Succinic anhydried 8g and diacetyl oxide 40mL, catalyzer 4-Dimethylamino pyridine 0.5g, this mixed system is 2bar at pressure; Temperature is after reacting 2h under 85 ℃ of conditions, stopped reaction.
(2) product extracts: esterification is reduced to normal temperature after finishing, and in product, adds suitable quantity of water; Make the product precipitating, and with 3 extremely tasteless 60 ℃ of dryings down, fractionation by distillation acetone of being placed on of boiling water washing; Promptly obtain product, draw acetyl content 8.2% (massfraction, down together) through detecting; Succinyl content 12.5% (massfraction, down together).
Embodiment 2
(1) esterification: in autoclave, add raw material Vltra tears 10g, solvent acetone 80mL, Succinic anhydried 9g; Catalyzer 4-Dimethylamino pyridine 1g, this mixed system is 1bar at pressure, temperature is reaction 30 minutes under 85 ℃ the condition; In this autoclave, add the 40mL diacetyl oxide then; It is constant to keep former temperature of reaction, after continuing to react 2h, and stopped reaction.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of Hydrogen chloride and makes the product precipitating; Normal pressure filters, and product is dried fractionation by distillation acetone with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Promptly get title product, draw acetyl content 8.9% through detecting
,Succinyl content 13.2%.
Embodiment 3
(1) esterification: in autoclave, add raw material Vltra tears 10g, solvent acetone 500mL, Succinic anhydried 8g; Catalyzer 4-Dimethylamino pyridine 1g, diacetyl oxide 60mL, this mixed system is 5bar at pressure; Temperature is to react 4h, stopped reaction under 95 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 9.4%, succinyl content 11.9% through detecting.
Embodiment 4
(1) esterification: in autoclave, add raw material Vltra tears 10g, solvent acetone 40mL, Succinic anhydried 8g; Catalyzer 4-Dimethylamino pyridine 5g, diacetyl oxide 60mL, this mixed system is 2bar at pressure; Temperature is to react 7h, stopped reaction under 105 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 11.4%, succinyl content 14.5% through detecting.
Embodiment 5
(1) esterification: in autoclave, add raw material Vltra tears 10g, solvent acetone 80mL, Succinic anhydried 6g; Catalyzer 4-Dimethylamino pyridine 0.1g, this mixed system is 7bar at pressure, temperature is to react 1h under 85 ℃ the condition; In this autoclave, add the 50mL diacetyl oxide then; It is constant to keep former temperature of reaction, after continuing to react 7h, and stopped reaction.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of Hydrogen chloride and makes the product precipitating; Normal pressure filters; Product is dried to tasteless being placed in 60 ℃ of baking ovens with boiling water washing 3 times, and fractionation by distillation acetone promptly gets title product; Draw acetyl content 7.5%, succinyl content 10.7% through detecting.
Embodiment 6
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g; Solvent acetone 200mL, Succinic anhydried 15g, catalyzer 4-Dimethylamino pyridine 50g; Diacetyl oxide 100mL; This mixed system is 6bar at pressure, and temperature is to react 5h, stopped reaction under 100 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 12.6%, succinyl content 14.5% through detecting.
Embodiment 7
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g; Solvent acetone 90mL, Succinic anhydried 11g, catalyzer 4-Dimethylamino pyridine 2g; Diacetyl oxide 60mL; This mixed system is 10bar at pressure, and temperature is to react 24h, stopped reaction under 85 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 10.9%, succinyl content 13.3% through detecting.
Embodiment 8
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g, solvent acetone 80mL, Succinic anhydried 9g; Catalyzer 4-Dimethylamino pyridine 0.5g, this mixed system is 4bar at pressure, temperature is to react 2h under 50 ℃ the condition; In this autoclave, add the 30mL diacetyl oxide then; It is constant to keep former temperature of reaction, after continuing to react 10h, and stopped reaction.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of Hydrogen chloride and makes the product precipitating; Normal pressure filters, and product is dried fractionation by distillation acetone with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Promptly get title product, draw acetyl content 9.0% through detecting
,Succinyl content 12.3%.
Embodiment 9
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g; Solvent acetone 40mL, Succinic anhydried 8g, catalyzer 4-Dimethylamino pyridine 2g; Diacetyl oxide 60mL; This mixed system is 2bar at pressure, and temperature is to react 5h, stopped reaction under 130 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 10.3%, succinyl content 13.6% through detecting.
Embodiment 10
(1) esterification: in autoclave, add raw material Vltra tears 10g, solvent acetone 120mL, Succinic anhydried 3g; Catalyzer 4-Dimethylamino pyridine 2g, diacetyl oxide 70mL, this mixed system is 4bar at pressure; Temperature is to react 9h, stopped reaction under 85 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 9.3%, succinyl content 8.9% through detecting.
Embodiment 11
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g; Solvent acetone 250mL, Succinic anhydried 30g, catalyzer 4-Dimethylamino pyridine 4g; Diacetyl oxide 100mL; This mixed system is 3bar at pressure, and temperature is to react 9h, stopped reaction under 75 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 10.2%, succinyl content 15.1% through detecting.
Embodiment 13
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g; Solvent acetone 150mL, Succinic anhydried 10g, catalyzer 4-Dimethylamino pyridine 4g; Diacetyl oxide 10mL; This mixed system is 2bar at pressure, and temperature is to react 5h, stopped reaction under 115 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 7.7%, succinyl content 9.4% through detecting.
Embodiment 14
(1) esterification: in autoclave (U.S. PARR pressure stirred autoclave-4500 series), add raw material Vltra tears 10g; Solvent acetone 80mL, Succinic anhydried 12g, catalyzer 4-Dimethylamino pyridine 6g; Diacetyl oxide 270mL; This mixed system is 4bar at pressure, and temperature is to react 5h, stopped reaction under 100 ℃ of conditions.
(2) purification of products: esterification is reduced to room temperature after finishing, and in container, adds an amount of water; Make the product precipitating, normal pressure filters, and product is dried with boiling water washing 3 times to tasteless being placed in 60 ℃ of baking ovens; Fractionation by distillation acetone; Promptly get title product, draw acetyl content 13.3%, succinyl content 11.8% through detecting.
The infrared spectrogram of above-mentioned instance (like instance 1) product is as shown in Figure 1, can be found out that by Fig. 1 product is at wave number 1750cm
-1There is strong absorption peak at the place, and this is the absorption peak of carbonyl; At 1066cm
-1The absorption peak at place is the C-O-C stretching vibration peak; 1454cm
-1The absorption peak at place is-CH
3The flexural vibration peak; 2941cm
-1The absorption peak at place is-CH
3Stretching vibration peak; 3473cm
-1The place is the absorption peak of-OH.Can confirm to have synthesized title product thus.
The foregoing description is a preferred implementation of the present invention; But embodiment of the present invention is not restricted to the described embodiments; Other any do not deviate from change, the modification made under spirit of the present invention and the principle, substitutes, combination, simplify; All should be the substitute mode of equivalence, be included within protection scope of the present invention.
Claims (10)
1. the preparation method of hydroxypropyl methylcellulose acetate succinate under the novel dissolvent system, its characteristic comprises following operation steps:
(1) esterification: Vltra tears, inert solvent, esterifying agent, catalyzer are joined in the reaction vessel, and heated and stirred is carried out esterification;
(2) product extracts: after esterification finishes, be cooled to normal temperature after, add precipitation agent, make the product precipitating, washed product, the fractionation by distillation inert solvent obtains hydroxypropyl methylcellulose acetate succinate.
2. preparation method according to claim 1; It is characterized in that inert solvent is a hydrophilic organic solvent-acetone, 1 described in the step (1), the 4-dioxane; In the N more than one, the amount ratio of said inert solvent and Vltra tears are 4-50 mL/g.
3. preparation method according to claim 1; It is characterized in that; The described esterifying agent of step (1) is diacetyl oxide and Succinic anhydried, and said diacetyl oxide and Vltra tears amount ratio are mL/g for 0.3-30 unit, and said diacetyl oxide and Vltra tears weight ratio are 0.3-30.
4. preparation method according to claim 3 is characterized in that, said diacetyl oxide of step (1) and Succinic anhydried add or add earlier wherein a kind of participation reaction simultaneously, and then add a kind of in addition.
5. preparation method according to claim 1 is characterized in that, the described catalyzer of step (1) does
, R wherein
1And R
2Be C
nH
2n+1, n=is a positive integer, consumption is 0.01 ~ 5 times of Vltra tears quality.
6. preparation method according to claim 5 is characterized in that said n=1, and promptly said catalyzer is the 4-Dimethylamino pyridine.
7. preparation method according to claim 1 is characterized in that, the temperature of the said esterification of step (1) is 50-130 ℃, and the reaction times is 2-24h, and pressure is 1-10bar.
8. preparation method according to claim 1 is characterized in that, the said reaction vessel of step (1) is autoclave or there-necked flask.
9. preparation method according to claim 1 is characterized in that, the described precipitation agent of step (2) is deionized water, Hydrogen chloride or dilute sulphuric acid, and the amount ratio of precipitation agent and said esterification products is 20-1000 mL/g.
10. according to each preparation method of 8 of claim 1～9, it is characterized in that deionized water or boiling water are adopted in the said washing of step (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101784407A CN102702363A (en) | 2012-06-01 | 2012-06-01 | Preparation method of hydroxypropyl methylcellulose acetate succinate in novel solvent system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101784407A CN102702363A (en) | 2012-06-01 | 2012-06-01 | Preparation method of hydroxypropyl methylcellulose acetate succinate in novel solvent system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102702363A true CN102702363A (en) | 2012-10-03 |
Family
ID=46895449
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012101784407A Pending CN102702363A (en) | 2012-06-01 | 2012-06-01 | Preparation method of hydroxypropyl methylcellulose acetate succinate in novel solvent system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102702363A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104311674A (en) * | 2014-10-17 | 2015-01-28 | 广东东阳光药业有限公司 | Preparation method of mixed ester |
| CN104945516A (en) * | 2015-07-06 | 2015-09-30 | 德清县维康生物科技有限公司 | Acetic acid hydroxypropyl methyl cellulose succinic acid ester and preparing method |
| CN105273088A (en) * | 2015-11-16 | 2016-01-27 | 泰安瑞泰纤维素有限公司 | Novel technology for preparing hydroxypropyl methyl cellulose derivative |
| CN105330754A (en) * | 2015-11-25 | 2016-02-17 | 泰安瑞泰纤维素有限公司 | Preparation method of hydroxypropyl methyl cellulose derivative under novel green reaction medium |
| JP2016532725A (en) * | 2013-09-23 | 2016-10-20 | ダウ グローバル テクノロジーズ エルエルシー | Process for recovering esterified cellulose ether from reaction product mixture |
| CN107406521A (en) * | 2015-03-16 | 2017-11-28 | 陶氏环球技术有限责任公司 | Method for preparing esterified cellulose ether in the presence of aliphatic carboxylic acid |
| CN107567463A (en) * | 2015-05-15 | 2018-01-09 | 陶氏环球技术有限责任公司 | The technique for preparing HMW esterified cellulose ether |
| CN108245700A (en) * | 2018-01-22 | 2018-07-06 | 河南汇博医疗股份有限公司 | A kind of hydroxypropyl methyl cellulose chitosan film dressing and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101200393A (en) * | 2006-12-15 | 2008-06-18 | 中国科学院沈阳应用生态研究所 | Membrane material for producing coated material and preparation technique thereof |
-
2012
- 2012-06-01 CN CN2012101784407A patent/CN102702363A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101200393A (en) * | 2006-12-15 | 2008-06-18 | 中国科学院沈阳应用生态研究所 | Membrane material for producing coated material and preparation technique thereof |
Non-Patent Citations (2)
| Title |
|---|
| 邵自强等: "醋酸轻丙基甲基纤维素唬拍酸醋的性能表征", 《中国药学杂志》 * |
| 郑一平等: "纤维素混合醚酯的开发与应用", 《纤维素科学与技术》 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2016532725A (en) * | 2013-09-23 | 2016-10-20 | ダウ グローバル テクノロジーズ エルエルシー | Process for recovering esterified cellulose ether from reaction product mixture |
| EP3049446B1 (en) | 2013-09-23 | 2017-05-03 | Dow Global Technologies LLC | A process for recovering an esterified cellulose ether from a reaction product mixture |
| CN104311674A (en) * | 2014-10-17 | 2015-01-28 | 广东东阳光药业有限公司 | Preparation method of mixed ester |
| CN107406521A (en) * | 2015-03-16 | 2017-11-28 | 陶氏环球技术有限责任公司 | Method for preparing esterified cellulose ether in the presence of aliphatic carboxylic acid |
| CN107406521B (en) * | 2015-03-16 | 2019-04-05 | 陶氏环球技术有限责任公司 | Method for preparing esterified cellulose ether in the presence of aliphatic carboxylic acid |
| CN107567463A (en) * | 2015-05-15 | 2018-01-09 | 陶氏环球技术有限责任公司 | The technique for preparing HMW esterified cellulose ether |
| CN104945516A (en) * | 2015-07-06 | 2015-09-30 | 德清县维康生物科技有限公司 | Acetic acid hydroxypropyl methyl cellulose succinic acid ester and preparing method |
| CN105273088A (en) * | 2015-11-16 | 2016-01-27 | 泰安瑞泰纤维素有限公司 | Novel technology for preparing hydroxypropyl methyl cellulose derivative |
| CN105330754A (en) * | 2015-11-25 | 2016-02-17 | 泰安瑞泰纤维素有限公司 | Preparation method of hydroxypropyl methyl cellulose derivative under novel green reaction medium |
| CN108245700A (en) * | 2018-01-22 | 2018-07-06 | 河南汇博医疗股份有限公司 | A kind of hydroxypropyl methyl cellulose chitosan film dressing and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102702363A (en) | Preparation method of hydroxypropyl methylcellulose acetate succinate in novel solvent system | |
| CN110551327B (en) | Method for preparing conductive composite material by using pyrrole grafted nano-cellulose | |
| CN102020735B (en) | Purification method of polyvinyl alcohol | |
| WO2009149657A1 (en) | Macroporous adsorption resin special for extracting cephalosporin c and its preparation method | |
| CN103626879A (en) | Mechanical activation and enhancement method for preparing cellulose acetate-butyrate or cellulose acetate-propionate | |
| CN104761673B (en) | A kind of carbomer and preparation method thereof | |
| CN109134670A (en) | A kind of preparation method of acetyl cellulose propionate and its mixed ester | |
| CN101225115A (en) | Precipitation modifying method for cellulose type solid enteric coatings | |
| CN110483678B (en) | Catalyst for preparing isosorbide by dehydrating sorbitol and preparation method and application thereof | |
| CN104788609A (en) | Highly cross-linked monodisperse epoxy-group-containing polymeric microsphere and preparation method thereof | |
| CN114367311B (en) | Method for preparing micron-sized monodisperse polymer microsphere supported heteropolyacid catalyst by suspension polymerization method and application thereof | |
| CN111499661A (en) | Preparation method of tin oxide complex diisooctanoate | |
| CN106589035A (en) | Preparation process of prednisolone acetate | |
| CN112023900B (en) | Preparation method of secondary cross-linked resin adsorbent and secondary cross-linked resin adsorbent | |
| EP0477347A1 (en) | Process for preparing cellulose esters by use of carboxylic acids. | |
| CN110407946A (en) | A kind of method that carried superstrong solid acid catalysis prepares Triafol T | |
| CN113150184B (en) | Method for preparing acetylated sodium hyaluronate | |
| CN102827230A (en) | Preparation method of hydrocortisone acetate | |
| CN107162914B (en) | Microwave-assisted three-phase transfer catalytic synthesis method for diallyl phthalate | |
| CN101596464B (en) | Circular type esterification reaction polymer catalyst and preparation method and application thereof | |
| CN111944083B (en) | Preparation method of modified macroporous acidic cation exchange resin | |
| CN112316980A (en) | Method for preparing cellulose acetate propionate by catalysis of zirconium dioxide/polymethacrylate microsphere-loaded heteropoly acid catalyst | |
| CN113603796A (en) | Preparation method of cellulose acetate butyrate | |
| CN105273088A (en) | Novel technology for preparing hydroxypropyl methyl cellulose derivative | |
| CN106146673A (en) | By waste paper cellulose acetate method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20121003 |