CN115403585A - Ionic liquid, preparation method thereof and application thereof in cellulose transesterification modification - Google Patents
Ionic liquid, preparation method thereof and application thereof in cellulose transesterification modification Download PDFInfo
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Abstract
The invention discloses ionic liquid, a preparation method thereof and application thereof in cellulose transesterification modification. Firstly, a series of amphiphilic ionic liquids are prepared by using superbase and long-chain chloralkane, and the ionic liquids have excellent solubility to biomass raw materials. After the obtained ionic liquid is used for dissolving cellulose, under the conditions of milder reaction and no need of adding extra catalyst, the cellulose ester derivative with high substitution degree is obtained by transesterification reaction with a plurality of alkenyl esters. The obtained cellulose ester derivative powder is subjected to hot pressing treatment to obtain a transparent cellulose film material. The cellulose ester derivative is prepared by homogeneous phase transesterification in the ionic liquid, the reaction efficiency is high, the substitution degree of the obtained product is high, the thermoplastic processing performance is good, and the cellulose ester derivative has potential application value in the field of petroleum-based plastic substitute materials.
Description
Technical Field
The invention relates to an ionic liquid, a preparation method thereof and application thereof in cellulose transesterification modification, belonging to the field of biomass modification and material preparation.
Background
Cellulose is the most abundant natural polymer resource on earth, and is a renewable organic resource. Cellulose has a wide range of properties such as biocompatibility, recyclability, hydrophilicity, good adsorption capacity, non-toxicity, and the like. The cellulose material can be in different forms such as powder, flake, film, filament and the like, so that the cellulose material has a wide application range. Particularly, in recent years, with the increasing importance of various countries on the problem of environmental pollution, biodegradable and environmentally friendly cellulose materials have become hot spots for competitive development in various countries in the world.
Structurally, cellulose is a linear polymer consisting of D-glucose through beta-1, 4 glycosidic bonds, hydroxyl groups on the carbons of the sugar rings of the repeating units of the cellulose have good reactivity, and the hydroxyl groups can be modified and converted into different cellulose derivatives containing ether bonds, aldehyde groups, ester groups and the like through a chemical method. Cellulose acetate is one of the common cellulose ester derivatives, and is widely used in various fields due to its good properties. The esterification of cellulose can be divided into homogeneous modification and heterogeneous modification, and compared with a heterogeneous system of direct reaction, cellulose acetate obtained by dissolving cellulose in a solvent and then carrying out esterification modification in the homogeneous system has more controllable substitution degree, and the substitution degree is more uniform.
Dissolution of cellulose is one of the core problems in the homogeneous modification of cellulose. Cellulose has strong hydrogen bond action among molecules and in molecules, so that the cellulose has the characteristics of high crystallinity, stable physical and chemical properties and higher glass transition temperature, and is insoluble in water and common organic solvents. There are many cellulose dissolution methods reported at present, and conventional methods such as cuprammonium method and viscose method, although widely used industrially, are gradually replaced by greener new solvent systems due to more serious environmental problems. The most studied solvent systems currently include: paraformaldehyde/dimethyl sulfoxide, lithium chloride/dimethylacetamide, NMMO, ionic liquids, lithium hydroxide/urea/water, sodium hydroxide/urea/water, and the like, wherein the ionic liquids are receiving wide attention because they exhibit great application potential in the preparation of cellulose materials.
Ionic liquids, also known as room temperature ionic liquids, room temperature molten Salts (RILs), organic ionic liquids, and the like, refer to ionic systems that are in a liquid state at room temperature or slightly warmer. The organic nitrogen salt is a salt composed of organic nitrogen cations and inorganic anions, and can dissolve biomass raw materials such as cellulose and lignin under relatively mild conditions. Research on preparation of cellulose acetate by dissolving cellulose with ionic liquid and performing homogeneous transesterification reaction is concerned with important industrial application value, but the reported preparation process of the ionic liquid is complex, and more organic solvents are often used, so that the application of the ionic liquid is limited. In addition, the direct transesterification efficiency of the existing ionic liquid is very low, and cellulose acetate with higher substitution degree cannot be obtained, so that the reaction efficiency needs to be improved by additionally adding a catalyst, improving the reaction temperature and prolonging the reaction time in an experiment. These limits the application of ionic liquid in homogeneous phase transesterification to prepare cellulose ester derivatives to some extent. After dissolving cellulose with a common ionic liquid, amimCl, as a solvent and DMSO as a cosolvent, e.g. Wen et al, 0.3g of DBU (1, 8-diazabicyclo [5.4.0] undec-7-ene) as a catalyst and vinyl laurate as an esterifying agent were added to obtain a cellulose ester with a substitution DS =2.74 by transesterification reaction for 6h at 120 ℃ (X.Wen et al, preparation and characterization of cellulose sulfate by purified transesterification, arbohydrate Polymers 168 (2017) 247-254). The preparation of the ionic liquid needs the participation of an organic solvent, and the solvent is removed through rotary evaporation after the reaction is finished to obtain the product. These all limit the application of ionic liquid in the preparation of cellulose ester derivatives by transesterification.
Disclosure of Invention
In order to realize green and efficient esterification of cellulose, the invention prepares a series of ionic liquids by simple blending and heating, realizes dissolution and homogeneous phase transesterification modification of cellulose under mild conditions, and the prepared cellulose ester derivatives can be further processed into film materials by thermoplastic processing.
The technical scheme of the invention is as follows:
the structure of the ionic liquid is selected from any one of the following structural formulas:
preferably, the R group in the structural general formula of the ionic liquid is long-chain alkane selected from amyl (-CH) 2 CH 2 CH 2 CH 2 CH 3 ) Hexyl (-CH) 2 CH 2 CH 2 CH 2 CH 2 CH 3 ) Heptyl (-CH) 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 ) Octyl (-CH) 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 ) Nonyl group (-CH) 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 ) Decyl (-CH) 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 ) To (3) is provided.
Preferably, X in the above-mentioned general structural formula of the ionic liquid - Is an anion selected from chloride Cl - Bromine ion Br - Acetate ion Ac - To (3) is provided.
The invention provides a preparation method of the ionic liquid. The ionic liquid is prepared by mixing the superbase and the long-chain chloralkane according to the molar ratio of 1: 0.75-1, and heating and stirring the mixture for 10-30 h at the temperature of 55-75 ℃.
Preferably, the superbase is selected from one of 1, 5-diazabicyclo [4.3.0] -5-nonene, 1, 8-diazabicyclo [5.4.0] undec-7-ene.
Preferably, the long-chain chloroalkane is selected from one of 1-chloropentane, 1-chlorohexane, 1-chloroheptane, 1-chlorooctane, 1-chlorononane and 1-chlorodecane.
The invention provides an application of the ionic liquid in cellulose transesterification modification, which specifically comprises the following steps: the obtained ionic liquid is used as a reaction medium to be applied to transesterification reaction to prepare cellulose ester derivatives, and finally, the cellulose film material can be prepared. The method specifically comprises the following steps:
(1) Heating and stirring the prepared ionic liquid at 90-110 ℃ for 1-3 h to dissolve 2-5 wt% of cellulose, adding an esterifying agent according to the molar ratio of 1: 3-12 of a cellulose dehydration glucose unit and the esterifying agent, and heating and stirring at 70-130 ℃ for 20-90 min to obtain a cellulose ester derivative solution;
(2) Mixing the cellulose esterification derivative solution obtained in the step (1) with ethanol, washing for multiple times by using vacuum filtration to remove residual reactants, ionic liquid and the like, and drying the washed cellulose ester derivative in a vacuum oven at 50-100 ℃ for 10-20 h to remove water and ethanol to obtain dried cellulose ester derivative powder;
(3) And (3) hot-pressing the cellulose ester derivative powder obtained in the step (2) for 10-30 min at 180-200 ℃ under the pressure of 10-30 MPa to obtain the cellulose film material.
Preferably, the cellulose comprises one of microcrystalline cellulose, cotton linters, bleached hardwood pulp, bleached softwood pulp, and bleached bamboo pulp.
Preferably, the esterifying agent is one selected from vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, isopropenyl acetate, vinyl benzoate, vinyl cinnamate and vinyl laurate.
The degree of substitution of the cellulose ester derivatives prepared by the invention is 1.08-2.85.
Compared with the prior reported homogeneous transesterification reaction for preparing the cellulose ester derivatives, the method has the following advantages:
(1) Compared with common ionic liquid, the ionic liquid synthesized by the method is reported for the first time, the preparation process is simpler, the reaction conditions are milder, only reactants are mixed and heated, and no solvent is needed.
(2) Compared with most of reported methods, the preparation method has the advantages of short reaction time (40 min) and generally low reaction temperature (80 ℃) of the cellulose ester derivatives. Meanwhile, the cellulose ester has no thermoplasticity when the degree of substitution is low, and has hot processing capability when the degree of substitution is high, so that the cellulose ester derivative prepared by the invention has high degree of substitution (DS is approximately equal to 3), and the degree of substitution can be regulated and controlled by changing reaction conditions.
(3) DBN (1, 5-diazabicyclo [4.3.0] -5-nonene) and DBU (1, 8-diazabicyclo [5.4.0] undec-7-ene) in the ionic liquid have an autocatalytic effect, and no catalyst is required to be additionally added in the transesterification reaction.
(4) The cellulose ester derivative prepared by the invention has good hot processing performance, and can be subjected to melt processing in a hot pressing mode to obtain a transparent cellulose plastic film material.
Drawings
FIG. 1 shows a NMR spectrum of a cellulose acetate powder obtained in example 4 of the present invention.
FIG. 2 is a scanning electron micrograph of a cellulose acetate powder obtained in example 4 of the present invention.
FIG. 3 is a scanning electron micrograph of a film obtained by hot pressing the cellulose acetate powder obtained in example 4 of the present invention.
Detailed Description
The present invention will be further described with reference to specific examples. It should be noted that the embodiments described below are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the invention without making any inventive step, shall fall within the scope of protection of the claims of this application.
Example 1
(1) Ionic liquids [ DBNC 5 ]The preparation of Cl, the synthetic route is as follows:
in a 250mL single-neck flask, superbase DBN (1, 5-diazabicyclo [4.3.0] was added in a molar ratio of 1: 0.85]24.8g (0.2mol, 1.0 eq.) of (5-nonene) and 18.1g (0.17mol, 1.0 eq.) of 1-chloropentane were charged with nitrogen and stirred at 55 deg.CStirring for 20h to obtain orange transparent viscous liquid, i.e. prepared ionic liquid [ DBNC 5 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBNC ] 5 ]Cl 8g into a flask, 5wt% cellulose (microcrystalline cellulose, 0.40 g) was added and heated and stirred at 90 ℃ for 2h until a uniform and transparent cellulose solution was formed. Then, vinyl acetate (2.54 g) was added in a molar ratio of 1: 12 between the anhydroglucose units of cellulose and the esterifying agent, and the mixture was reacted at 70 ℃ for 40min. After the reaction is finished, the product is washed by ethanol for many times and is subjected to vacuum filtration to remove the solvent, the unreacted esterifying agent and the like. And finally, drying the sample at 50 ℃ in vacuum for 10h to obtain cellulose acetate powder, and calculating the substitution degree DS =1.08 through a nuclear magnetic resonance hydrogen spectrogram.
Example 2
(1) Ionic liquid [ DBUC ] 5 ]The preparation of Cl and the synthetic route are as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added in a molar ratio of 1: 1]Undec-7-ene) 30.4g (0.2mol, 1.0 eq.) and 1-chloropentane 21.3g (0.2mol, 1.0 eq.) were introduced into a nitrogen atmosphere, heated and stirred at 55 ℃ for 24 hours to obtain an orange transparent viscous liquid, namely the prepared ionic liquid [ DBUC ] 5 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBUC ] 5 ]Cl 8g into a flask, 5wt% cellulose (microcrystalline cellulose, 0.40 g) was added and heated and stirred at 100 ℃ for 2h until a uniform and transparent cellulose solution was formed. Then, vinyl acetate (2.54 g) was added in a molar ratio of 1: 12 between the anhydroglucose units of cellulose and the esterifying agent, and the mixture was reacted at 70 ℃ for 40min. After the reaction is finished, the product is washed by ethanol for many times, and is filtered in vacuum to remove the solvent, the unreacted esterifying agent and the like. And finally, drying the sample at 75 ℃ in vacuum for 15h to obtain cellulose acetate powder, and calculating by using a nuclear magnetic resonance hydrogen spectrogram to obtain the substitution degree DS =1.49.
Example 3
(1) Ionic liquid [ DBUC 8 ]The preparation of Cl and the synthetic route are as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added at a molar ratio of 1: 1]Undec-7-ene) 30.4g (0.2mol, 1.0eq.) and 1-chlorooctane 29.7g (0.2mol, 1.0eq.) were introduced, nitrogen gas was introduced for protection, and the mixture was heated and stirred at 65 ℃ for 24 hours to obtain orange transparent viscous liquid, namely the prepared ionic liquid [ DBUC ] 8 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBUC ] 8 ]Cl 8g in a flask, 4wt% cellulose (bleached hardwood pulp, 0.32 g) was added and stirred at 90 ℃ for 2h until a homogeneous transparent cellulose solution was formed. Then, vinyl acetate (1.52 g) was added in a molar ratio of anhydroglucose units of cellulose to the esterifying agent of 1: 9, and the mixture was reacted at 100 ℃ for 40min. After the reaction is finished, the product is washed by ethanol for many times, and is filtered in vacuum to remove the solvent, the unreacted esterifying agent and the like. And finally, drying the sample at 100 ℃ for 20h in vacuum to obtain cellulose acetate powder, and calculating the substitution degree DS =2.57 through a nuclear magnetic resonance hydrogen spectrogram.
(3) Preparation of cellulose acetate film
Spreading a small amount of cellulose acetate powder between two polyimide films, and hot pressing at 200 deg.C and 10Mpa for 20min to obtain transparent cellulose acetate film.
Example 4
(1) Ionic liquid [ DBUC ] 8 ]The preparation of Cl, the synthetic route is as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added in a molar ratio of 1: 1]Undec-7-ene) 30.4g (0.2mol, 1.0 eq.) and 29.7g (0.2mol, 1.0 eq.) of 1-chlorooctane are introduced into the reactor, nitrogen is introduced into the reactor for protection, and the mixture is heated and stirred at 55 ℃ for 24 hours to obtain orange transparent viscous liquid, namely the prepared ionic liquid [ DBUC ] 8 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBUC ] 8 ]Cl 8g into a flask, 2wt% cellulose (microcrystalline cellulose, 0.16 g) was added and heated and stirred at 90 ℃ for 2h until a uniform transparent cellulose solution was formed. Then, vinyl acetate (1.02 g) was added in a molar ratio of anhydroglucose units of cellulose to esterifying agent of 1: 12, and the mixture was reacted at 80 ℃ for 40min. After the reaction is finished, the product is washed by ethanol for many times and is subjected to vacuum filtration to remove the solvent, the unreacted esterifying agent and the like. Finally, the sample was dried under vacuum at 50 ℃ for 20 hours to obtain cellulose acetate powder. The nmr hydrogen spectrum of the obtained cellulose acetate is shown in fig. 1, and the substitution degree DS =2.82 is calculated by the formula. The scanning electron micrograph of the obtained cellulose acetate powder is shown in FIG. 2.
(3) Preparation of cellulose acetate film
Spreading a small amount of cellulose acetate powder between two polyimide films, and hot pressing at 180 deg.C and 20Mpa for 10min to obtain transparent cellulose acetate film. Scanning electron micrographs of the surface (left) and cross section (right) of the film are shown in FIG. 3, from which it can be seen that the cellulose acetate film obtained by hot pressing is denser in both surface and cross section.
Example 5
(1) Ionic liquid [ DBUC 8 ]The preparation of Cl, the synthetic route is as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added at a molar ratio of 1: 1]Undec-7-ene) 30.4g (0.2mol, 1.0 eq.) and 1-chlorooctane 29.7g (0.2mol, 1.0 eq.) were added with nitrogen to protect, heated at 55 deg.C and stirred for 24h to obtain orange transparent viscous liquid, i.e. the prepared ionic liquid [ DBUC ] 8 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBUC ] 8 ]Cl 8g into a flask, 4wt% cellulose (microcrystalline cellulose, 0.32 g) was added and heated and stirred at 90 ℃ for 2h until a uniform and transparent cellulose solution was formed. Then, vinyl acetate (2.04 g) was added in a molar ratio of anhydroglucose units of cellulose to esterifying agent of 1: 12, and the mixture was reacted at 100 ℃ for 20min. After the reaction is finished, the product is washed by ethanol for many times, and is filtered in vacuum to remove the solvent, the unreacted esterifying agent and the like. And finally, drying the sample in vacuum at 50 ℃ for 20h to obtain cellulose acetate powder, and calculating through a nuclear magnetic resonance hydrogen spectrum to obtain the substitution degree DS =2.57.
(3) Preparation of cellulose acetate film
Spreading a small amount of cellulose acetate powder between two polyimide films, and hot pressing at 190 deg.C and 20Mpa for 20min to obtain transparent cellulose acetate film.
Example 6
(1) Ionic liquid [ DBUC 8 ]The preparation of Cl, the synthetic route is as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added in a molar ratio of 1: 1]Undec-7-ene) 30.4g (0.2mol, 1.0 eq.) and 1-chlorooctane 29.7g (0.2mol, 1.0 eq.) were added with nitrogen to protect, heated at 55 deg.C and stirred for 24h to obtain orange transparent viscous liquid, i.e. the prepared ionic liquid [ DBUC ] 8 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBUC ] 8 ]Cl 8g into a flask, 4wt% of cellulose (bleached softwood pulp, 0.32 g) was added, heated and stirred at 100 ℃ for 2 hours until a uniform and transparent cellulose solution was formed, and then vinyl butyrate (1.35 g) was added in a molar ratio of anhydroglucose units of cellulose to an esterifying agent of 1: 6, and reacted at 100 ℃ for 40 minutes. After the reaction is finished, the product is washed by ethanol for many times, and is filtered in vacuum to remove the solvent, the unreacted esterifying agent and the like. Finally, the sample is placed inVacuum drying at 50 deg.C for 20h to obtain cellulose acetate powder, and calculating by NMR hydrogen spectrum to obtain substitution degree DS =2.45.
(3) Preparation of cellulose acetate film
Spreading a small amount of cellulose acetate powder between two polyimide films, and hot pressing at 200 deg.C and 30Mpa for 30min to obtain transparent cellulose acetate film.
Example 7
(1) Ionic liquid [ DBUC ] 8 ]The preparation of Cl and the synthetic route are as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added in a molar ratio of 1: 1]Undec-7-ene) 30.4g (0.2mol, 1.0 eq.) and 1-chlorooctane 29.7g (0.2mol, 1.0 eq.) were added with nitrogen to protect, heated at 55 deg.C and stirred for 24h to obtain orange transparent viscous liquid, i.e. the prepared ionic liquid [ DBUC ] 8 ]Cl。
(2) Preparation of cellulose laurate ester
Taking the above ionic liquid [ DBUC ] 8 ]Cl 8g into a flask, add 4wt% cellulose (microcrystalline cellulose, 0.32 g), heat stir at 90 ℃ for 1h until a uniform transparent cellulose solution is formed. Then, vinyl laurate (5.35 g) was added in a molar ratio of the anhydroglucose units of cellulose to the esterifying agent of 1: 12, and the mixture was reacted at 130 ℃ for 90 minutes. After the reaction is finished, the product is washed by ethanol for many times, and is filtered in vacuum to remove the solvent, the unreacted esterifying agent and the like. And finally, drying the sample in vacuum at 50 ℃ for 20h to obtain lauric acid cellulose ester powder, and calculating through a nuclear magnetic resonance hydrogen spectrogram to obtain the substitution degree DS =2.85.
(3) Preparation of a film of cellulose laurate
Spreading a small amount of lauric acid cellulose ester powder between two polyimide films, and hot-pressing at 180 ℃ and 10MPa for 20min to obtain the transparent lauric acid cellulose ester film.
Example 8
(1) Ionic liquid [ DBUC 10 ]The preparation of Cl, the synthetic route is as follows:
in a 250mL single-neck flask, superbase DBU (1, 8-diazabicyclo [5.4.0] was added in a molar ratio of 1: 0.75]Undec-7-ene) 30.4g (0.2mol, 1.0eq.) and 1-chlorodecane 26.5g (0.15mol, 1.0eq.) were introduced, nitrogen was introduced for protection, and the mixture was heated and stirred at 75 ℃ for 30 hours to obtain an orange transparent viscous liquid, i.e., the prepared ionic liquid [ DBUC ] 10 ]Cl。
(2) Preparation of cellulose acetate
Taking the above ionic liquid [ DBUC ] 10 ]Cl 8g into a flask, 2wt% of cellulose (microcrystalline cellulose, 0.16 g) was added, and the mixture was heated and stirred at 110 ℃ for 3 hours until a uniform and transparent cellulose solution was formed, and then vinyl acetate (0.76 g) was added in a molar ratio of anhydroglucose units of cellulose to esterifying agent of 1: 9, and reacted at 100 ℃ for 60 minutes. After the reaction is finished, the product is washed by ethanol for many times and is subjected to vacuum filtration to remove the solvent, the unreacted esterifying agent and the like. And finally, drying the sample at 50 ℃ in vacuum for 20h to obtain cellulose acetate powder, and calculating by using a nuclear magnetic resonance hydrogen spectrum to obtain the substitution degree DS =2.66.
(3) Preparation of cellulose acetate film
Spreading a small amount of cellulose acetate powder between two polyimide films, and hot pressing at 190 deg.C and 10Mpa for 20min to obtain transparent cellulose acetate film.
Claims (10)
1. The ionic liquid is characterized in that the structure of the ionic liquid is selected from any one of the following structural formulas:
wherein, the R group is selected from one of amyl, hexyl, heptyl, octyl, nonyl and decyl; anion X - Selected from the group consisting of chloride ionDaughter Cl - Bromine ion Br - Acetate ion Ac - One kind of (1).
2. The preparation method of the ionic liquid as claimed in claim 1, characterized in that the ionic liquid is prepared by mixing the superbase and the long-chain chloroalkane according to the molar ratio of 1 to (0.75-1), and heating and stirring at 55-75 ℃ for 10-30 h.
3. The method of claim 2, wherein the superbase is selected from 1, 5-diazabicyclo [4.3.0] -5-nonene, 1, 8-diazabicyclo [5.4.0] undec-7-ene.
4. The method for preparing the ionic liquid as claimed in claim 2, wherein the long-chain chloroalkane is selected from one of 1-chloropentane, 1-chlorohexane, 1-chloroheptane, 1-chlorooctane, 1-chlorononane and 1-chlorodecane.
5. Use of the ionic liquid of claim 1 for the transesterification modification of cellulose.
6. The application of the ionic liquid in the transesterification modification of the cellulose according to claim 5, wherein the ionic liquid is used as a reaction medium for preparing the cellulose ester derivatives by the transesterification reaction, and finally preparing the cellulose film material.
7. The application of the ionic liquid in cellulose transesterification modification according to claim 6, is characterized by comprising the following steps:
(1) Heating and stirring the prepared ionic liquid at 90-110 ℃ for 1-3 h to dissolve 2-5 wt% of cellulose, adding an esterifying agent according to the molar ratio of 1: 3-12 of a cellulose dehydration glucose unit and the esterifying agent, and heating and stirring at 70-130 ℃ for 20-90 min to obtain a cellulose ester derivative solution;
(2) Mixing the cellulose ester derivative solution obtained in the step (1) with ethanol, carrying out suction filtration and washing, and putting the washed cellulose esterified derivative into a vacuum oven at 50-100 ℃ for drying for 10-20 h to obtain dried cellulose ester derivative powder;
(3) And (3) hot-pressing the cellulose ester derivative powder obtained in the step (2) for 10-30 min at 180-200 ℃ under 10-30 MPa to obtain the cellulose film material.
8. The use of the ionic liquid in cellulose transesterification modification according to claim 7, wherein the cellulose comprises one of microcrystalline cellulose, cotton linters, bleached hardwood pulp, bleached softwood pulp, and bleached bamboo pulp.
9. The use of the ionic liquid in cellulose transesterification according to claim 7, wherein the esterifying agent is selected from one of vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, isopropenyl acetate, vinyl benzoate, vinyl cinnamate, and vinyl laurate.
10. Use of the ionic liquid according to any one of claims 5 to 9 for the transesterification of cellulose, wherein the degree of substitution of the cellulose ester derivative produced is in the range of 1.08 to 2.85.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3652564A (en) * | 1969-12-01 | 1972-03-28 | Syntex Corp | 5-alkyl-1 6-fused cycloalkylene-tetrahydro-1 5-diazine salts |
| CN101522985A (en) * | 2006-10-13 | 2009-09-02 | 巴斯夫欧洲公司 | Ionic liquids for solubilizing polymers |
| CN104024265A (en) * | 2011-12-02 | 2014-09-03 | 道康宁公司 | Ester-functional silanes and the preparation and use thereof |
| CN105175746A (en) * | 2015-07-29 | 2015-12-23 | 广东省微生物研究所 | Wood fiber homogeneous phase transesterification modification method |
| CN110358122A (en) * | 2019-08-23 | 2019-10-22 | 仲恺农业工程学院 | A kind of hemicellulose -ester laminated film, preparation method and applications |
-
2022
- 2022-08-12 CN CN202210972765.6A patent/CN115403585A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3652564A (en) * | 1969-12-01 | 1972-03-28 | Syntex Corp | 5-alkyl-1 6-fused cycloalkylene-tetrahydro-1 5-diazine salts |
| CN101522985A (en) * | 2006-10-13 | 2009-09-02 | 巴斯夫欧洲公司 | Ionic liquids for solubilizing polymers |
| CN104024265A (en) * | 2011-12-02 | 2014-09-03 | 道康宁公司 | Ester-functional silanes and the preparation and use thereof |
| CN105175746A (en) * | 2015-07-29 | 2015-12-23 | 广东省微生物研究所 | Wood fiber homogeneous phase transesterification modification method |
| CN110358122A (en) * | 2019-08-23 | 2019-10-22 | 仲恺农业工程学院 | A kind of hemicellulose -ester laminated film, preparation method and applications |
Non-Patent Citations (4)
| Title |
|---|
| "CAS-RN：108141-04-4，108141-03-3，108141-01-1", 《REGISTRY》 * |
| JANUSZ NOWICKI ET AL.: "Novel basic ionic liquids from cyclic guanidines and amidines–new catalysts for transesterification of oleochemicals", 《J CHEM TECHNOL BIOTECHNOL》 * |
| KALLIDANTHIYIL CHELLAPPAN LETHESH ET AL.: "Synthesis, Characterization, and Thermophysical Properties of 1,8-Diazobicyclo[5.4.0]undec-7-ene Based Thiocyanate Ionic Liquids", 《J. CHEM. ENG. DATA》 * |
| ZIDONG ZHANG ET AL.: "Preparation and Application of CO2‑Triggered Switchable Solvents in Separation of Toluene/ n‑Heptane", 《LANGMUIR》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117343204A (en) * | 2023-12-04 | 2024-01-05 | 北京林业大学 | Cellulose surface esterification product and preparation method and application thereof |
| CN117343204B (en) * | 2023-12-04 | 2024-03-12 | 北京林业大学 | Cellulose surface esterification product and preparation method and application thereof |
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