CN105622778A

CN105622778A - Preparation method of water-soluble chitosan

Info

Publication number: CN105622778A
Application number: CN201410590867.7A
Authority: CN
Inventors: 麦亚孙
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-10-29
Filing date: 2014-10-29
Publication date: 2016-06-01

Abstract

The invention provides a preparation method of water-soluble chitosan. The method comprises the following steps: preprocessing chitin, carrying out deacetyl extraction on the preprocessed chitin through an aqueous alkaline solution to prepare chitosan, purifying the chitosan to obtain high quality chitosan, and esterifying the prepared chitosan to substantially improve the water solubility and the degradability of chitosan, The method provides reliable reference bases for addition of the water-soluble chitosan to grafted starch filled polyethylene and development of a chitosan and polyethylene/starch degradable plastic blend system.

Description

A kind of preparation method of water-soluble chitosan

Technical field

The present invention relates to a kind of preparation method, the preparation method refering in particular to a kind of water-soluble chitosan.

Background technology

Chitosan (chitosan), also known as chitosan, is that the chitin (chitin) being widely present by nature obtains through deacetylation, and chemical name is Chitosan (1-4)-2-amino-B-D glucose. From 1859, after first Frenchman Rouget obtains chitosan, the premium properties such as the biological functionality of this natural polymer and the compatibility, blood compatibility, safety, microbic resolvability are by all trades and professions extensive concern, and the applied research at numerous areas such as medicine, food, chemical industry, cosmetics, water process, METAL EXTRACTION and recovery, biochemistry and biomedical engineerings achieves major progress. For patient, chitosan blood fat reducing, the existing research report of hypoglycemic effect. Meanwhile, chitosan is taken as thickening agent, fruit glaze agent is listed state food additive in and used standard GB-2760.

By the method for preparing chitosan from chitin, currently mainly have: (1) utilizes high-concentration alkali liquor and chitin to react for a long time under relatively low temperature; Process time length needed for the method, gained chitosan deacetylation relatively low; (2) high-concentration alkali liquor and chitin is utilized at high temperature to carry out the reaction of short time; The method energy consumption is high, the viscosity of chitosan product is low; (3) also have the report utilizing the mixture of microwave treatment chitin and alkali liquor to prepare chitosan in recent years, though the method so that deacetylated speed is accelerated, shortened the response time, but can still belong to intermittently operated, be unfavorable for continuous prodution.

Summary of the invention

The preparation method that it is an object of the invention to provide a kind of water-soluble chitosan.

For reaching above-mentioned purpose, the present invention adopts and is made by method:

(1) chitin pulverized is processed 3 times in 5 ~ 15 DEG C with the NaOH aqueous solution of 20 ~ 80% (w/w) under nitrogen protection, the 1/5-1/30 that amount is NaOH solution weight of the chitin added, each 1 ~ 20h, cooling, filtration, with about 80 DEG C hot water, product is washed till neutrality, vacuum drying at 60 DEG C;

(2) sample is dissolved in the acetic acid aqueous solution of 0.5 ~ 5%, is made into the Chitosan Solution of 0.5 ~ 5%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C.

(3) take chitosan sample 1g and add 0.1M acetic acid 90ml in triangular flask, by magnetic agitation, until complete soln, regulating PH is 4.0 ~ 6.0, add distilled water and supply volume to 100ml, then obtaining concentration is the chitosan solution of 10mg/ml, and it is stand-by that the used time is diluted to suitable concn with PH=5.0 acetic acid.

(4) a certain amount of chitosan and formic acid are added reactor, N₂In 30 ~ 90 DEG C of constant temperature stirring 0.5 ~ 10h, polymer dissolving under protection, addition ice vinegar stirring, to homogeneous phase, adds acetic anhydride, stirs extremely to react and terminates, and the thick liquid of gained precipitates in methanol, and precipitation uses methanol, acetone clean after pulverizing, and dries and to obtain end product.

Detailed description of the invention:

Below by specific embodiment, technical scheme is described in further detail, but the present invention is not limited to these embodiments.

Embodiment one:

(1) chitin pulverized is processed 3 times in 15 DEG C with the NaOH aqueous solution of 20% (w/w) under nitrogen protection, amount is NaOH solution weight the 1/5 of the chitin added, each 20h, cooling, filtration, with about 80 DEG C hot water, product is washed till neutrality, vacuum drying at 60 DEG C;

(2) sample is dissolved in the acetic acid aqueous solution of 0.5%, is made into the Chitosan Solution of 0.5%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C.

(3) take chitosan sample 1g and add 0.1M acetic acid 90ml in triangular flask, by magnetic agitation, until complete soln, regulating PH is 4.0, add distilled water and supply volume to 100ml, then obtaining concentration is the chitosan solution of 10mg/ml, and it is stand-by that the used time is diluted to suitable concn with PH=5.0 acetic acid.

(4) a certain amount of chitosan and formic acid are added reactor, N₂In 90 DEG C of constant temperature stirring 0.5h, polymer dissolving under protection, addition ice vinegar stirring, to homogeneous phase, adds acetic anhydride, stirs extremely to react and terminates, and the thick liquid of gained precipitates in methanol, and precipitation uses methanol, acetone clean after pulverizing, and dries and to obtain end product.

Embodiment two:

(1) chitin pulverized is processed 3 times in 5 DEG C with the NaOH aqueous solution of 60% (w/w) under nitrogen protection, amount is NaOH solution weight the 1/20 of the chitin added, each 1h, cooling, filtration, with about 80 DEG C hot water, product is washed till neutrality, vacuum drying at 60 DEG C;

(2) sample is dissolved in the acetic acid aqueous solution of 5%, is made into the Chitosan Solution of 5%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C.

(3) take chitosan sample 1g and add 0.1M acetic acid 90ml in triangular flask, by magnetic agitation, until complete soln, regulating PH is 6.0, add distilled water and supply volume to 100ml, then obtaining concentration is the chitosan solution of 10mg/ml, and it is stand-by that the used time is diluted to suitable concn with PH=5.0 acetic acid.

(4) a certain amount of chitosan and formic acid are added reactor, N₂In 30 DEG C of constant temperature stirring 5h, polymer dissolving under protection, addition ice vinegar stirring, to homogeneous phase, adds acetic anhydride, stirs extremely to react and terminates, and the thick liquid of gained precipitates in methanol, and precipitation uses methanol, acetone clean after pulverizing, and dries and to obtain end product.

Embodiment three:

(1) chitin pulverized is processed 3 times in 10 DEG C with the NaOH aqueous solution of 80% (w/w) under nitrogen protection, amount is NaOH solution weight the 1/30 of the chitin added, each 10h, cooling, filtration, with about 80 DEG C hot water, product is washed till neutrality, vacuum drying at 60 DEG C;

(2) sample is dissolved in the acetic acid aqueous solution of 3%, is made into the Chitosan Solution of 3%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C.

(3) take chitosan sample 1g and add 0.1M acetic acid 90ml in triangular flask, by magnetic agitation, until complete soln, regulating PH is 5.0, add distilled water and supply volume to 100ml, then obtaining concentration is the chitosan solution of 10mg/ml, and it is stand-by that the used time is diluted to suitable concn with PH=5.0 acetic acid.

(4) a certain amount of chitosan and formic acid are added reactor, N₂In 40 DEG C of constant temperature stirring 10h, polymer dissolving under protection, addition ice vinegar stirring, to homogeneous phase, adds acetic anhydride, stirs extremely to react and terminates, and the thick liquid of gained precipitates in methanol, and precipitation uses methanol, acetone clean after pulverizing, and dries and to obtain end product.

Embodiment four:

(1) chitin pulverized is processed 3 times in 10 DEG C with the NaOH aqueous solution of 50% (w/w) under nitrogen protection, amount is NaOH solution weight the 1/10 of the chitin added, each 4h, cooling, filtration, with about 80 DEG C hot water, product is washed till neutrality, vacuum drying at 60 DEG C;

(2) sample is dissolved in the acetic acid aqueous solution of 2%, is made into the Chitosan Solution of 2%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C.

(4) a certain amount of chitosan and formic acid are added reactor, N₂In 55 DEG C of constant temperature stirring 1.5h, polymer dissolving under protection, addition ice vinegar stirring, to homogeneous phase, adds acetic anhydride, stirs extremely to react and terminates, and the thick liquid of gained precipitates in methanol, and precipitation uses methanol, acetone clean after pulverizing, and dries and to obtain end product.

Claims

1. the preparation method of a water-soluble chitosan, it is characterised in that comprise the following steps:

(2) sample is dissolved in the acetic acid aqueous solution of 0.5 ~ 5%, is made into the Chitosan Solution of 0.5 ~ 5%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C;

(3) take chitosan sample 1g and add 0.1M acetic acid 90ml in triangular flask, by magnetic agitation, until complete soln, regulating PH is 4.0 ~ 6.0, add distilled water and supply volume to 100ml, then obtaining concentration is the chitosan solution of 10mg/ml, and it is stand-by that the used time is diluted to suitable concn with PH=5.0 acetic acid;

2. the preparation method of a kind of water-soluble chitosan according to claim 1, it is characterised in that comprise the following steps:

(2) sample is dissolved in the acetic acid aqueous solution of 2%, is made into the Chitosan Solution of 2%, after the insoluble impurity of elimination, under stirring, be poured slowly into 1moldm^-3In NaOH solution, placing several hours under meta-alkalescence, filter, the sample water obtained is washed till neutrality, then with isopropyl alcohol wash two to three times, vacuum drying at 70 DEG C;

(3) take chitosan sample 1g and add 0.1M acetic acid 90ml in triangular flask, by magnetic agitation, until complete soln, regulating PH is 5.0, add distilled water and supply volume to 100ml, then obtaining concentration is the chitosan solution of 10mg/ml, and it is stand-by that the used time is diluted to suitable concn with PH=5.0 acetic acid;