Chitosan / starch crosslinked derivative, and preparation method and application thereof

Abstract

The application provides a chitosan / starch crosslinked derivative, a preparation method and application thereof. The derivative comprises the following raw materials: a chitosan starch compound and ozone. In the application, the chitosan starch compound and ozone are selected as the raw materials, the chitosan and the starch in the chitosan starch compound form a physical complex, under the action of the ozone, the chitosan and the starch in the compound are chemically crosslinked to form a covalent force, a crosslinked derivative with stable structure and function is formed, meanwhile, the ozone can also make the chitosan starch compound produce an aldehyde group, a Schiff base is formed through one-step reaction, a stable derivative crosslinked system is formed, thereby excellent water absorption capacity and water retention capacity are achieved, and the chitosan starch compound and the ozone are widely sourced and low in cost, and are suitable for large-scale industrial production.

Description

Technical Field

[0001] This application relates to the field of natural polymer technology, and in particular to a chitosan / starch crosslinked derivative and its preparation method and application. Background Technology

[0002] Natural starch is prone to retrogradation, has poor stability, relatively high density, and is insoluble in water, which limits its industrial use. Related technologies utilize chitosan to complex with starch to construct starch-based composite materials. These composite materials are used to form nanoparticles, hydrogels, artificial tissues, antibacterial films, and other products, which are widely used in the food industry and biopharmaceuticals.

[0003] The complexation methods for chitosan and starch generally include physical, chemical, enzymatic, and genetic engineering. Physical complexation involves intermolecular forces that cause chitosan and starch to form a cross-linked network structure; however, the forces between starch and chitosan after the mixture are non-covalent interactions, resulting in relatively weak complexation stability.

[0004] Chemical complexation, through chemically induced covalent cross-linking, can enhance the structural and functional stability of chitosan / starch complexes. Chemical complexation primarily involves adding chemical cross-linking agents or oxidizing starch to form a Schiff base reaction between chitosan and oxidized starch, resulting in a tighter and more stable complex system. However, chemical cross-linking agents may generate a large number of harmful substances during the complexation process; and the Schiff base reaction between oxidized starch and chitosan requires repeated use of water as a solvent, making the process cumbersome and costly.

[0005] Application content

[0006] This application is made in view of the above-mentioned issues, and its purpose is to provide a chitosan / starch crosslinked derivative; the raw materials for preparing the derivative are of low cost.

[0007] This application also provides a method for preparing the above-mentioned derivatives, which is simple and low in cost.

[0008] This application also provides applications of the aforementioned derivatives.

[0009] To achieve the above objectives, the first aspect of this application provides a chitosan / starch crosslinked derivative, comprising the following raw materials:

[0010] Chitosan starch complex and ozone.

[0011] According to one of the technical solutions of the derivative technology of this application, at least the following beneficial effects are achieved:

[0012] In this application, chitosan-starch composite and ozone are selected as raw materials. In the chitosan-starch composite, chitosan and starch form a physical complex. Under the action of ozone, chitosan and starch in the composite undergo chemical cross-linking, forming covalent forces and forming a structurally and functionally stable cross-linked derivative. At the same time, ozone can also generate aldehyde groups in the chitosan-starch composite, forming a Schiff base (which is formed by the condensation of an amine and an active carbonyl group) through a one-step reaction, thus forming a stable derivative cross-linking system. Therefore, it has excellent water absorption and water retention capacity. Moreover, chitosan-starch composite and ozone are widely available and low in cost, making them suitable for large-scale industrial production.

[0013] Optionally, the mass ratio of the chitosan starch complex to ozone is 100:(0.1-4).

[0014] Excessive ozone dosage results in strong oxidizing power, which can lead to the degradation of some chitosan-starch complexes, thereby reducing the utilization rate of the complexes. Insufficient ozone dosage leads to incomplete oxidation, resulting in weaker covalent cross-linking and a relative decrease in performance.

[0015] Optionally, the chitosan-starch complex comprises the following raw materials:

[0016] Chitosan, starch, and acetic acid.

[0017] Chitosan can dissolve in acetic acid solution, thus mixing thoroughly with starch to form a chitosan-starch complex.

[0018] Optionally, the mass ratio of chitosan to starch is (0.01-9):100.

[0019] If the amount of chitosan used is too large, it will be difficult to dissolve and will not be conducive to thorough mixing with starch. Chitosan can reduce the interaction force between starch molecules. If the amount of chitosan used is too small, the effect of reducing the interaction force between starch molecules will be poor, thus affecting the water absorption capacity of the final cross-linked derivative.

[0020] Optionally, the viscosity of the chitosan is below 200 mPa·s.

[0021] If the viscosity of chitosan is too high, the mobility of the chitosan molecular chain segments will be lower, which is not conducive to the dispersion of chitosan.

[0022] The second aspect of this application provides a method for preparing the above-mentioned chitosan / starch crosslinked derivative, comprising the following steps:

[0023] The chitosan-starch complex was treated with ozone.

[0024] The preparation method of this application only requires ozone treatment of the chitosan starch complex. The operation steps are simple, the cost is low, and it is conducive to large-scale industrial production.

[0025] Optionally, the ozone treatment time is 5 min to 60 min.

[0026] If the ozone treatment time is too long, it will cause some chitosan starch complex to degrade, thereby reducing the utilization rate of the complex; if the ozone treatment time is too short, the oxidation will be incomplete, resulting in weak covalent cross-linking and a relative decrease in performance.

[0027] Optionally, the temperature for ozone treatment is 10°C to 30°C.

[0028] Ozone treatment can be carried out at room temperature without the need for additional heating, which helps to simplify the production process.

[0029] Optionally, the method for preparing the chitosan-starch complex includes the following steps:

[0030] Chitosan, starch, acetic acid, and water are mixed and then dried.

[0031] Chitosan has a certain viscosity and contains many free amino and hydroxyl groups in its molecules; while acetic acid can fully promote the dissolution of chitosan, thereby enabling sufficient physical cross-linking between chitosan and starch molecular chains.

[0032] The third aspect of this application provides the use of the above-mentioned chitosan / starch crosslinked derivative in the preparation of at least one of water-absorbing agents, water-retaining agents, and antibacterial agents. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this drawing or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this drawing. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0034] Figure 1 The image shows the infrared detection results of the cross-linked derivative of Example 1 (corresponding to ODCSS in the figure), starch in Comparative Example 1 (corresponding to DS in the figure), chitosan-starch complex in Comparative Examples 2-3 (comparative example 2 corresponds to DCSS in the figure, and comparative example 3 corresponds to DOCSS in the figure), chitosan (corresponding to CS in the figure), ozonated chitosan (corresponding to OCS in the figure), and ozonated starch (corresponding to ODS in the figure).

[0035] Figure 2This is a magnified view of the infrared detection results of the crosslinked derivative of Example 1 (corresponding to ODCSS in the figure), starch in Comparative Example 1 (corresponding to DS in the figure), chitosan-starch complex in Comparative Examples 2-3 (comparative Example 2 corresponds to DCSS in the figure, and Comparative Example 3 corresponds to DOCSS in the figure), chitosan (corresponding to CS in the figure), ozono-chitosan (corresponding to OCS in the figure), and ozono-starch (corresponding to ODS in the figure).

[0036] Figure 3 The graph shows the solubility and swelling power test results of the cross-linked derivative of Example 1 and the starch in Comparative Example 1, and the chitosan-starch complex in Comparative Examples 2-3.

[0037] Figure 4 The graph shows the water-holding capacity and water absorption index test results of the cross-linked derivative of Example 1, the starch in Comparative Example 1, and the chitosan-starch complexes in Comparative Examples 2-3.

[0038] The purpose, features, and advantages of this accompanying drawing will be further explained in conjunction with the embodiments and with reference to the accompanying drawing. Detailed Implementation

[0039] The following detailed description, with appropriate reference to the accompanying drawings, discloses embodiments of the chitosan / starch crosslinked derivatives of this application, their preparation methods, and their applications. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of essentially identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0040] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0041] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0042] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0043] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0044] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0045] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0046] In a first aspect, this application provides a chitosan / starch crosslinked derivative, comprising the following raw materials:

[0047] Chitosan starch complex and ozone.

[0048] This application has at least the following beneficial effects:

[0049] In this application, chitosan-starch composite and ozone are selected as raw materials. In the chitosan-starch composite, chitosan and starch form a physical complex; under the action of ozone, chitosan and starch in the composite undergo chemical cross-linking, forming covalent forces; thus forming a structurally and functionally stable cross-linked derivative. At the same time, ozone can also generate aldehyde groups in the chitosan-starch composite, forming a Schiff base (which is formed by the condensation of an amine and an active carbonyl group) through a one-step reaction, forming a stable derivative cross-linking system. Therefore, it has excellent water absorption and water retention capacity. Moreover, chitosan-starch composite and ozone are widely available and low in cost, making them suitable for large-scale industrial production.

[0050] In some embodiments, the mass ratio of the chitosan starch complex to ozone is 100:0.1 to 4.

[0051] Excessive ozone dosage results in strong oxidizing power, which can lead to the degradation of some chitosan-starch complexes, thereby reducing the utilization rate of the complexes. Insufficient ozone dosage leads to incomplete oxidation, resulting in weaker covalent cross-linking and a relative decrease in performance.

[0052] In some embodiments, the mass ratio of the chitosan starch complex to ozone is 100:0.1 to 3.

[0053] In some embodiments, the chitosan-starch complex comprises the following raw materials:

[0054] Chitosan, starch, and acetic acid.

[0055] Chitosan can dissolve in acetic acid solution, thus mixing thoroughly with starch to form a chitosan-starch complex.

[0056] In some embodiments, the chitosan-starch complex comprises the following raw materials:

[0057] Chitosan, starch, acetic acid, and water.

[0058] In some embodiments, the mass ratio of chitosan to starch is (0.01-9):100.

[0059] If the amount of chitosan used is too large, it will be difficult to dissolve and will not be conducive to thorough mixing with starch. Chitosan can reduce the interaction force between starch molecules. If the amount of chitosan used is too small, the effect of reducing the interaction force between starch molecules will be poor, thus affecting the water absorption capacity of the final cross-linked derivative.

[0060] In some embodiments, the mass ratio of chitosan to starch is (1-9):100.

[0061] In some embodiments, the mass ratio of chitosan to starch is (6-9):100.

[0062] In some embodiments, the viscosity of the chitosan is below 200 mPa·s.

[0063] If the viscosity of chitosan is too high, the mobility of the chitosan molecular chain segments will be lower, which is not conducive to the dispersion of chitosan.

[0064] Secondly, this application provides a method for preparing the above-mentioned chitosan / starch crosslinked derivative, comprising the following steps:

[0065] The chitosan-starch complex was treated with ozone.

[0066] The preparation method of this application only requires ozone treatment of the chitosan starch complex. The operation steps are simple, the cost is low, and it is conducive to large-scale industrial production.

[0067] In some embodiments, the ozone treatment time is 5 min to 60 min.

[0068] In some embodiments, the ozone treatment time is 30 min to 60 min.

[0069] If the ozone treatment time is too long, it will cause some chitosan starch complex to degrade, thereby reducing the utilization rate of the complex; if the ozone treatment time is too short, the oxidation will be incomplete, resulting in weak covalent cross-linking and a relative decrease in performance.

[0070] In some embodiments, the temperature of the ozone treatment is 10°C to 30°C.

[0071] Ozone treatment can be carried out at room temperature without the need for additional heating, which helps to simplify the production process.

[0072] In some embodiments, the method for preparing the chitosan-starch complex includes the following steps:

[0073] Chitosan, starch, acetic acid, and water are mixed and then dried.

[0074] Chitosan has a certain viscosity and contains many free amino and hydroxyl groups in its molecules; while acetic acid can fully promote the dissolution of chitosan, thereby enabling sufficient physical cross-linking between chitosan and starch molecular chains.

[0075] In some embodiments, the method for preparing the chitosan-starch complex includes the following steps:

[0076] Chitosan and acetic acid solution are mixed to prepare chitosan solution;

[0077] Starch was added to a chitosan solution and dispersed to obtain a chitosan-starch suspension;

[0078] The chitosan starch suspension was dried and then ground.

[0079] In some embodiments, the acetic acid solution is prepared by mixing acetic acid and water.

[0080] In some embodiments, the mass concentration of the acetic acid solution is 0.5% to 3%.

[0081] In some embodiments, the mass concentration of the acetic acid solution is 0.5% to 1%.

[0082] In some embodiments, the mass-to-volume ratio of chitosan to acetic acid solution is (1g to 3g): 100mL.

[0083] In some embodiments, the mass-to-volume ratio of the starch and acetic acid solution is (40g-50g):100mL.

[0084] In some embodiments, the chitosan and acetic acid solution are mixed for 0.5 h to 1 h.

[0085] In some embodiments, the dispersion time is 0.5h to 1h.

[0086] In some embodiments, the drying temperature is 50°C to 60°C.

[0087] In some embodiments, the drying time is 20h to 30h.

[0088] In some embodiments, the drying time is 20h to 24h.

[0089] In some embodiments, the particle size after grinding is 100 mesh to 200 mesh.

[0090] Thirdly, this application provides the application of the above-mentioned chitosan / starch crosslinked derivative in the preparation of at least one of water-absorbing agents, water-retaining agents, and antibacterial agents.

[0091] The following are some of the raw materials used in the embodiments and comparative examples of this application, and their manufacturers:

[0092] Starch: Glutinous rice flour (glutinous rice starch) purchased from Jiangsu Baobao Suqian Guomin Biotechnology Co., Ltd.

[0093] Chitosan (CAS No.: 9012-76-4): purchased from Maclean's Reagents (Catalog No.: C804728), low viscosity: <200 mPa·s.

[0094] Ozone generator: Feili ozone sterilizer, ozone flux: 3000mg / h.

[0095] Preparation of acetic acid solution: Prepare a 1% acetic acid solution by mixing distilled water and acetic acid in a ratio of 1:99.

[0096] Example 1

[0097] This embodiment is a chitosan / starch crosslinked derivative, composed of the following raw materials:

[0098] Chitosan starch complex and ozone.

[0099] In this embodiment, the chitosan-starch complex is composed of the following raw materials:

[0100] Chitosan, starch, and acetic acid solution (1% by mass).

[0101] The mass fractions of chitosan are 3 parts, starch is 47 parts, and ozone is 1.5 parts.

[0102] The mass-to-volume ratio of chitosan to acetic acid solution is 3g:100mL.

[0103] The preparation method of the chitosan / starch crosslinked derivative in this embodiment consists of the following steps:

[0104] The chitosan-starch complex was treated with ozone oxidation for 30 minutes.

[0105] The preparation method of the chitosan-starch complex in this embodiment consists of the following steps:

[0106] S1. Add chitosan to acetic acid solution and stir magnetically for 1 hour at room temperature (25℃) to obtain chitosan solution;

[0107] S2. Add starch to chitosan solution and stir for 1 hour to obtain chitosan starch suspension;

[0108] S3. Dry the chitosan starch suspension at 50℃ for 24 hours, grind it, pass it through a 100-mesh sieve, and collect the sieve residue.

[0109] Comparative Example 1

[0110] This comparative example uses starch.

[0111] Comparative Example 2

[0112] This comparative example is a chitosan-starch complex, composed of the following raw materials:

[0113] Chitosan, starch, and acetic acid solution (1% by mass).

[0114] The chitosan content is 3 parts by weight and the starch content is 47 parts by weight.

[0115] The mass-to-volume ratio of chitosan to acetic acid solution is 3g:100mL.

[0116] The preparation method of the chitosan-starch complex in this comparative example consists of the following steps:

[0117] S1. Add chitosan to acetic acid solution and stir magnetically for 1 hour at room temperature (25℃) to obtain chitosan solution;

[0118] S2. Add starch to chitosan solution and stir for 1 hour to obtain chitosan starch suspension;

[0119] S3. Dry the chitosan starch suspension at 50℃ for 24 hours, grind it, pass it through a 100-mesh sieve, and collect the sieve residue.

[0120] Comparative Example 3

[0121] This comparative example is a chitosan-starch complex, composed of the following raw materials:

[0122] Chitosan, starch, ozone, and acetic acid solution (1% by mass).

[0123] The mass fractions of chitosan are 3 parts, starch is 47 parts, and ozone is 1.5 parts.

[0124] The mass-to-volume ratio of chitosan to acetic acid solution is 3g:100mL.

[0125] The preparation method of the chitosan-starch complex in this comparative example consists of the following steps:

[0126] S1. Add chitosan to acetic acid solution and stir magnetically for 1 hour at room temperature (25℃) to obtain chitosan solution;

[0127] S2. Add starch to chitosan solution and stir for 1 hour to obtain chitosan starch suspension;

[0128] S3. Ozone is introduced into the chitosan starch suspension while magnetic stirring is performed. The ozone treatment time is 30 minutes to obtain the oxidation treatment suspension.

[0129] S3. Dry the oxidized suspension at 50°C for 24 hours, grind it, pass it through a 100-mesh sieve, and collect the sieve residue.

[0130] To further compare the differences in functional group structures among the various substances, ozono-oxidized chitosan and ozono-oxidized starch were prepared. The specific preparation steps are as follows:

[0131] Ozone-oxidized chitosan preparation method:

[0132] After drying 25g of chitosan powder at 50℃ for 24h, place it in a dry Buchner funnel, connect the Buchner funnel to a 250mL suction flask, and treat with ozone for 30min.

[0133] Ozoned starch preparation method:

[0134] 25g of starch was dried at 50℃ for 24 hours and then placed in a dry Buchner funnel. The Buchner funnel was connected to a 250mL suction flask and treated with ozone for 30 minutes.

[0135] The infrared detection results of the crosslinked derivative of Example 1 (corresponding to ODCSS in the figure), starch in Comparative Example 1 (corresponding to DS in the figure), chitosan-starch complexes in Comparative Examples 2 and 3 (Comparative Example 2 corresponds to DCSS in the figure, Comparative Example 3 corresponds to DOCSS in the figure), chitosan (corresponding to CS in the figure), ozonated chitosan (corresponding to OCS in the figure), and ozonated starch (corresponding to ODS in the figure) are shown in the figure. Figures 1-2 ;from Figures 1-2 It was found that the characteristic absorption peak of the Schiff base structure (1560 cm⁻¹) appeared in Example 1. -1 This means that chemical cross-linking was achieved in Example 1; 1372cm in the figure -1 The absorption peak corresponds to the diffraction peak of a hemiacetal formed from a carbonyl compound (aldehyde).

[0136] Table 1. Performance test results of Example 1 and Comparative Examples 1-3

[0137] Comparative Example 1 <![CDATA[0.58±0.07 b ]]> <![CDATA[17.22±0.63 a ]]> <![CDATA[7.16±1.89 a ]]> <![CDATA[16.22±0.63 a ]]> Comparative Example 2 <![CDATA[0.08±0.00 a ]]> <![CDATA[17.05±0.22 a ]]> <![CDATA[15.72±0.23 b ]]> <![CDATA[16.05±0.22 a ]]> Comparative Example 3 <![CDATA[0.07±0.01 a ]]> <![CDATA[18.41±0.59 a ]]> <![CDATA[17.07±0.47 b ]]> <![CDATA[17.41±0.59 a ]]> Example 1 <![CDATA[0.06±0.01 a ]]> <![CDATA[20.91±1.48 b ]]> <![CDATA[19.58±1.25 c ]]> <![CDATA[19.91±1.48 b ]]>

[0138] Note: a, b, and c in the table represent significance < 0.05.

[0139] The solubility and swelling power test results of the cross-linked derivative of Example 1 and the starch in Comparative Example 1, and the chitosan-starch complexes in Comparative Examples 2-3 are shown in the figure. Figure 3 (In the figure, a and b represent significance < 0.05), from Figure 3 It was found that the swelling power of the cross-linked derivative in Example 1 was much higher than that in Comparative Examples 1-3; the solubility of the cross-linked derivative in Example 1 was lower than that in Comparative Examples 1-3.

[0140] The water-holding capacity and water absorption index test results of the cross-linked derivative of Example 1 and the starch in Comparative Example 1, and the chitosan-starch complexes in Comparative Examples 2-3 are shown in the figure. Figure 4 (In the figure, a, b, and c represent significance < 0.05), from Figure 4 It was found that the water-holding capacity and water absorption index of the crosslinked derivative in Example 1 were much higher than those in Comparative Examples 1 to 3.

[0141] In this embodiment, chitosan and starch molecules form covalent bonds and crosslink, making the complex system more stable. The chitosan / starch crosslinking reaction process obtained in this embodiment is simple, reducing the use of solvents and chemical crosslinking agents. The water absorption and water retention properties of the chitosan / starch crosslinked derivative obtained in this embodiment are significantly improved.

[0142] In this embodiment, ozone is used as a gaseous crosslinking agent to facilitate the chemical dynamic crosslinking of chitosan and starch in a one-step process. Compared with the simple chitosan-starch complex, it exhibits improved swelling power, better water absorption and retention, and greater stability. Furthermore, ozone, as a natural oxidant, has strong oxidizing power and does not require a catalyst; direct treatment will significantly improve the properties of the chitosan-starch crosslinked derivative.

[0143] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A chitosan / starch crosslinked derivative, characterized in that, The following raw materials are included in the preparation: Chitosan starch complex and ozone, wherein the chitosan starch complex comprises chitosan, starch and acetic acid; The chitosan / starch crosslinked derivative is prepared by the following steps: mixing the chitosan and the acetic acid solution to obtain a chitosan solution; adding the starch to the chitosan solution and dispersing it to obtain a chitosan-starch suspension; drying and grinding the chitosan-starch suspension to obtain the chitosan-starch complex; and treating the chitosan-starch complex with ozone; wherein the ozone treatment time is 5 min to 60 min and the ozone treatment temperature is 10℃ to 30℃.

2. The chitosan / starch crosslinked derivative as described in claim 1, characterized in that, The mass ratio of the chitosan starch complex to ozone is 100:(0.1~4).

3. The chitosan / starch crosslinked derivative as described in claim 1, characterized in that, The mass ratio of chitosan to starch is (0.01~9):

100.

4. The chitosan / starch crosslinked derivative as described in claim 1, characterized in that, The viscosity of the chitosan is below 200 mPa·s.

5. The use of a chitosan / starch crosslinked derivative as described in any one of claims 1 to 4 in the preparation of at least one of a water-absorbing agent, a water-retaining agent, and an antibacterial agent.

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