CN101891841B - Novel method of alkylation for promoting high molecular weight chitosan by microwaves - Google Patents
Novel method of alkylation for promoting high molecular weight chitosan by microwaves Download PDFInfo
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- CN101891841B CN101891841B CN2010102537925A CN201010253792A CN101891841B CN 101891841 B CN101891841 B CN 101891841B CN 2010102537925 A CN2010102537925 A CN 2010102537925A CN 201010253792 A CN201010253792 A CN 201010253792A CN 101891841 B CN101891841 B CN 101891841B
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- chitosan
- reaction
- molecular weight
- substitution value
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- 229920001661 Chitosan Polymers 0.000 title claims abstract description 78
- 238000000034 method Methods 0.000 title abstract description 27
- 230000029936 alkylation Effects 0.000 title description 2
- 238000005804 alkylation reaction Methods 0.000 title description 2
- 230000001737 promoting effect Effects 0.000 title description 2
- 238000006467 substitution reaction Methods 0.000 claims abstract description 32
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000003513 alkali Substances 0.000 claims abstract description 4
- 238000006243 chemical reaction Methods 0.000 claims description 32
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 24
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 24
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 22
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 19
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims description 15
- 230000006196 deacetylation Effects 0.000 claims description 14
- 238000003381 deacetylation reaction Methods 0.000 claims description 14
- 230000008021 deposition Effects 0.000 claims description 12
- 238000001914 filtration Methods 0.000 claims description 12
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims description 12
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims description 12
- 238000003828 vacuum filtration Methods 0.000 claims description 12
- 238000005406 washing Methods 0.000 claims description 12
- 238000002360 preparation method Methods 0.000 claims description 7
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 3
- 125000000217 alkyl group Chemical group 0.000 claims description 3
- 239000012295 chemical reaction liquid Substances 0.000 claims description 2
- 239000000843 powder Substances 0.000 claims description 2
- 230000008961 swelling Effects 0.000 claims description 2
- 150000005826 halohydrocarbons Chemical class 0.000 abstract description 2
- 238000010438 heat treatment Methods 0.000 abstract 1
- 239000011259 mixed solution Substances 0.000 abstract 1
- 239000002994 raw material Substances 0.000 description 15
- 239000002253 acid Substances 0.000 description 10
- 238000013019 agitation Methods 0.000 description 10
- 238000003756 stirring Methods 0.000 description 10
- HNTGIJLWHDPAFN-UHFFFAOYSA-N 1-bromohexadecane Chemical compound CCCCCCCCCCCCCCCCBr HNTGIJLWHDPAFN-UHFFFAOYSA-N 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 6
- 239000012086 standard solution Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- -1 alkyl aldehydes Chemical class 0.000 description 2
- 230000031709 bromination Effects 0.000 description 2
- 238000005893 bromination reaction Methods 0.000 description 2
- RDHPKYGYEGBMSE-UHFFFAOYSA-N bromoethane Chemical compound CCBr RDHPKYGYEGBMSE-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical compound CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 238000004448 titration Methods 0.000 description 2
- DPDMMXDBJGCCQC-UHFFFAOYSA-N [Na].[Cl] Chemical compound [Na].[Cl] DPDMMXDBJGCCQC-UHFFFAOYSA-N 0.000 description 1
- 150000001335 aliphatic alkanes Chemical class 0.000 description 1
- 150000001350 alkyl halides Chemical class 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 150000002466 imines Chemical class 0.000 description 1
- 229960000907 methylthioninium chloride Drugs 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000009941 weaving Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
The invention discloses a novel method for alkalifying high molecular weight chitosan under the condition of microwave irradiation to prepare N-alkyl chitosan with high molecular weight and high substitution. The novel method is characterized by comprising the following steps: dispersing chitosan with the molecular weight of 900-1500 thousand and deacetylated degree of above 70% in a mixed solution of alkali and isopropanol, alkalifying under the condition of microwave irradiation, shifting out of a microwave reactor, heating to a certain temperature, dropwise adding halohydrocarbon (C2-C16) slowly, and processing to obtain the N-alkyl chitosan with the substitution of 40-70%.
Description
Technical field
The present invention relates to a kind ofly under microwave radiation, high molecular weight chitosan alkalized, preparation is than the novel method of high substitution value N-alkyl chitosan.
Background technology
The N-alkyl chitosan of HMW and substitution value has good film forming and fibre-forming performance, and is very wide in the application prospect of ecomaterial, weaving and medicine and other fields.At present, patent and document do not see that all the chitosan with HMW (＞90 ten thousand) is a raw material both at home and abroad, the report of the N-alkyl chitosan of preparation HMW and substitution value.Operational path for low-molecular-weight chitosan being feedstock production N-alkyl chitosan mainly contains two, route one, and chitosan and alkyl aldehydes reaction generate imines, pass through NaBH again
4Reduction, preparation N-alkyl chitosan.Xie Ying (applied chemistry, 2008,25 (10): 1201-1204) and Li Zuowei (foodstuffs industry science and technology, 2006,27 (8): 63-65) adopt this path of preparing N-alkyl chitosan, the chitosan molecule amount is generally 4～50,000; Xin Meihua (applied chemistry, 2005,22 (12): 1357-1359) adopt microwave irradiation technology that this technology is improved, shortened the reaction times, improved transformation efficiency, but the molecular weight of used chitosan is only about 3000; Li Mingchun (CN100503646C) has adopted this prepared disubstituted N-alkyl chitosan, the chitosan molecule amount of use also is no more than 10000.Route two, chitosan and haloalkane react in basic soln and directly make the N-alkyl chitosan.Yao Kangde (CN1386548A) adopts molecular weight 4～50,000, and deacetylation is a raw material greater than 90% chitosan, has prepared the N-alkyl chitosan of different degree of substitution; Liu (Bioconjugate Chem, 2003,14, also this technology is reported that 782-789) molecular weight of used chitosan is merely 50,000.Above two lines are raw material with the low-molecular weight chitoglycan all, and the N-alkyl chitosan molecular weight that makes is low, are difficult to reach the requirement of preparation high-performance chitosan film and fiber.Therefore the N-alkyl chitosan that how to prepare HMW and substitution value is very important.
Goal of the invention
The objective of the invention is in order to provide a kind of is raw material with the high molecular weight chitosan, the novel method of efficient production HMW and substitution value N-alkyl chitosan.
Summary of the invention
Technical scheme of the present invention is achieved in that at normal temperatures and pressures; With alkali (as, NaOH, KOH etc.), Virahol and chitosan powder add in the reaction flask together; It is mixed; Put it in the microwave reactor at power 300-600w, handled 5-60 minute, and obtained the uniform chitosan reaction liquid of swelling in alkali lye for 40～60 ℃.Then reaction flask is shifted out microwave reactor, be heated to certain temperature, slowly drip halohydrocarbon (C
2～C
16), its add-on for the amino of chitosan mol ratio be 1.1～1.2,40～100 ℃ of temperature of reaction, the reaction 3-4h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration obtains the alkyl chitosan product of HMW and high substitution value.
The present invention adopts molecular weight 90～1,500,000 of chitosan raw material, deacetylation＞70%, ash content＜0.6%.
The invention effect
The preparation method of the alkyl chitosan of HMW provided by the invention and substitution value is employed under the microwave radiation chitosan is alkalized; Destroyed between chitosan molecule or intramolecular strong hydrogen bonding effect; A large amount of amino is come out; Increase the touch opportunity with halogenated alkane, thereby accelerated speed of reaction.It can only be the shortcoming of feedstock production N-alkyl chitosan with the low-molecular weight chitoglycan that the present invention has overcome what exist in the background technology, for the preparation of the N-alkyl chitosan of HMW and substitution value provides a kind of effective ways.
Embodiment
Further specify below in conjunction with embodiment, and unrestricted scope involved in the present invention.
Embodiment 1:
The chitosan raw material: molecular weight 1,500,000, deacetylation are 85%, and ash content is 0.3%.
The measuring method of molecular weight: sample is dissolved in 0.2mol/L sodium-chlor+0.1mol/L acetic acid soln, under 25 ℃, measures with Ubbelodhe viscometer.Utilize one point method calculation sample limiting viscosity.With glutinous all relative molecular mass (K=1.81 * 10 of Mark-Houwink Equation for Calculating
-3Cm
3/ g, α=0.93).
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.10g chitosan, stir, put into microwave reactor,, 60 ℃, alkalized 1 hour at power 600w.Then there-necked flask is moved on to and is warmed up to 75 ℃ in the magnetic agitation well heater, slowly drip bromohexadecane, its add-on for the amino of chitosan mol ratio be 1.1, the reaction 3h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product.Adopting acid to record substitution value is 44.5%.The measuring method of substitution value is following:
Accurately take by weighing 0.3-0.5 gram alkylated chitosan sample, place the 250ml triangular flask, add standard 0.1mol/L (c
1) hydrochloric acid soln 30ml (v
1, ml), be stirred to dissolving complete (can add an amount of distilled water diluting) at 20-25 ℃, add 4-5 and drip indicator (tropeolin-D-methylene blue), with standard 0.1mol/L (c
2) sodium hydroxide solution titration to solution becomes pale bluish green, writes down sodium hydroxide solution consumption (v
2, ml); Other gets a alkylated chitosan sample, places 105 ℃ to dry to constant weight, measures moisture, and each sample need respectively be surveyed 3 times.
C in the formula
1The concentration of-hydrochloric acid standard solution, molL
-1
C
2The concentration of-standard solution of sodium hydroxide, molL
-1
V
1The volume of the hydrochloric acid standard solution of-adding, mL;
V
2The volume of the standard solution of sodium hydroxide that-titration consumes, mL;
The G-sample is heavy, g;
The moisture of W-sample, %;
0.016-with 1mL 1molL
-1The amino amount that hydrochloric acid soln is suitable, g;
The theoretical amino content of 0.0994-in the formula;
0.8477-the deacetylation of used chitosan;
Comparing embodiment 1:
The chitosan raw material: molecular weight 1,500,000, deacetylation are 85%, and ash content is 0.3%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.10g chitosan, stir, 0 ℃ alkalized 24 hours.Then there-necked flask is moved on to and is warmed up to 75 ℃ in the magnetic agitation well heater, slowly drip bromohexadecane, its add-on for the amino of chitosan mol ratio be 1.1, the reaction 3h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is zero basically.The measuring method of substitution value is seen embodiment 1.
Embodiment 2:
The chitosan raw material: molecular weight 1,000,000, deacetylation are 86%, and ash content is 0.4%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, put into microwave reactor,, 50 ℃, alkalized 1 hour at power 500w.Then there-necked flask is moved on to and is warmed up to 65 ℃ in the magnetic agitation well heater, slowly drip bromination of n-butane, its add-on for the amino of chitosan mol ratio be 1.2, the reaction 4h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 60.5%.The measuring method of substitution value is seen embodiment 1.
Comparing embodiment 2:
The chitosan raw material: molecular weight 1,000,000, deacetylation are 86%, and ash content is 0.4%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, 0 ℃ alkalized 26 hours.Then there-necked flask is moved on to and is warmed up to 65 ℃ in the magnetic agitation well heater, slowly drip bromination of n-butane, its add-on for the amino of chitosan mol ratio be 1.2, the reaction 4h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 10.5%.The measuring method of substitution value is seen embodiment 1.
Embodiment 3:
The chitosan raw material: molecular weight 1,000,000, deacetylation are 90%, and ash content is 0.4%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, put into microwave reactor,, 40 ℃, alkalized 1 hour at power 500w.Then there-necked flask is moved on to and be warmed up to 50 ℃ in the magnetic agitation well heater, slowly drip bromic ether, its add-on and amino of chitosan mol ratio are 1.2, reaction 3h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 62.5%.The measuring method of substitution value is seen embodiment 1.
Comparing embodiment 3:
The chitosan raw material: molecular weight 1,000,000, deacetylation are 90%, and ash content is 0.4%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, 0 ℃ alkalized 28 hours.Then there-necked flask is moved on to and be warmed up to 50 ℃ in the magnetic agitation well heater, slowly drip bromic ether, its add-on and amino of chitosan mol ratio are 1.2, reaction 3h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 12.5%.The measuring method of substitution value is seen embodiment 1.
Embodiment 4:
The chitosan raw material: molecular weight 1,500,000, deacetylation are 90%, and ash content is 0.3%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gKOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, put into microwave reactor,, 60 ℃, alkalized 0.5 hour at power 500w.Then there-necked flask is moved on to and be warmed up to 60 ℃ in the magnetic agitation well heater, slowly drip bromohexadecane, its add-on and amino of chitosan mol ratio are 1.1, reaction 4h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 60.5%.The measuring method of substitution value is seen embodiment 1.
Comparing embodiment 4:
The chitosan raw material: molecular weight 1,500,000, deacetylation are 90%, and ash content is 0.3%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gKOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, alkalized 26 hours down at 0 ℃.Then there-necked flask is moved on to and be warmed up to 60 ℃ in the magnetic agitation well heater, slowly drip bromohexadecane, its add-on and amino of chitosan mol ratio are 1.1, reaction 4h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 11.5%.The measuring method of substitution value is seen embodiment 1.
Embodiment 5:
The chitosan raw material: molecular weight 900,000, deacetylation are 85%, and ash content is 0.4%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir, put into microwave reactor,, 60 ℃, alkalized 1 hour at power 600w.Then there-necked flask is moved on to and be warmed up to 50 ℃ in the magnetic agitation well heater, slowly drip bromohexadecane, its add-on and amino of chitosan mol ratio are 1.1, reaction 3h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 72.5%.The measuring method of substitution value is seen embodiment 1.
Comparing embodiment 5:
The chitosan raw material: molecular weight 900,000, deacetylation are 85%, and ash content is 0.4%.The measuring method of molecular weight is seen embodiment 1.
At normal temperatures and pressures, in the there-necked flask that 2gNaOH and 40mL Virahol are housed, slowly add the 2.0g chitosan, stir,, alkalized 26 hours at 0 ℃.Then there-necked flask is moved on to and be warmed up to 50 ℃ in the magnetic agitation well heater, slowly drip bromohexadecane, its add-on and amino of chitosan mol ratio are 1.1, reaction 3h.Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration gets product, and adopting acid to record substitution value is 15.5%.The measuring method of substitution value is seen embodiment 1.
Claims (1)
1. the preparation method of an alkylated chitosan is characterized by under the normal temperature and pressure, with NaOH or KOH, Virahol and 1,500,000; Deacetylation＞70%; The chitosan powder of gray scale＜0.6% is placed in the reaction flask together, and it is mixed, and puts it in the microwave reactor at power 300-600w; Handled 5-60 minute, and obtained the uniform chitosan reaction liquid of swelling in alkali lye for 40～60 ℃; Then reaction flask is shifted out microwave reactor, be heated to certain temperature, slowly drip C
2～C
16Halohydrocarbon, its add-on for the amino of chitosan mol ratio be 1.1～1.2,40～100 ℃ of temperature of reaction, the reaction 3-4h; Reaction is neutralized to neutrality with product with Hydrogen chloride after finishing, deposition, filtration, and with ethanol, ether washing, vacuum filtration obtains the alkyl chitosan product of HMW and high substitution value.
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| CN104130423B (en) * | 2014-07-18 | 2016-06-08 | 武汉大学 | The preparation method of a kind of hydrophobicity chitin nanometer film |
| CN109181076A (en) * | 2018-09-20 | 2019-01-11 | 黄旭东 | A kind of preparation method of mould proof antifog polyethylene preservative film |
| CN111697234B (en) * | 2020-06-19 | 2022-09-02 | 中国地质大学（武汉） | Water-based crosslinking binder for lithium ion battery and preparation method and application thereof |
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Non-Patent Citations (3)
| Title |
|---|
| seiichi mima el.al..Highly deacetylated chitosan and its properties.《Journal of Applied Polymer Sciences》.1983,第28卷1909-1917. * |
| 代昭.烷基壳聚糖纳米微球的制备及其药物负载性能研究.《中国博士学位论文全文数据库》.2003,35-36. * |
| 王爱勤等.丁烷基壳聚糖的制备.《中国医药工业杂质》.1998,471,479. * |
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