polymer materials

Abstract

The present invention relates to a polymer material and its uses. The present invention can provide a polymer material that is both highly biodegradable and highly absorbable by using a polysaccharide having a specific functional group introduced therein. The present invention can also provide uses of the polymer material.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0008024, dated January 19, 2023, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference.

[0002] The present invention relates to polymeric materials and their applications. [Background technology]

[0003] Hydrogel Polymers or Hydrogels are generally defined as cross-linked hydrophilic polymers.

[0004] Such polymers may be used as materials known as SAPs (Super Absorbent Polymers). SAPs are materials that can absorb tens to thousands of times their own weight in water. SAPs are used in a variety of applications, including hygiene products such as sanitary napkins and diapers, medical supplies, daily necessities, agricultural materials, gardening materials, transportation materials, civil engineering and construction materials, materials related to electrical and electronic equipment, and water treatment agents.

[0005] The most widely used hydrogel polymers used as SAPs are vinyl-based materials such as cross-linked polyacrylic acid.

[0006] Although such materials are relatively inexpensive and have excellent water absorption capabilities, they remain semi-permanently even after disposal, causing various problems.

[0007] To solve this problem, there have been various attempts to produce SAP from so-called biodegradable materials.

[0008] However, currently known materials are unable to form SAPs with well-balanced physical properties. For example, while the most typical physical property required for SAPs is absorbency, currently known biodegradable SAPs do not sufficiently secure at least one of the properties of absorbency and biodegradability, or in some cases, do not secure both properties at an appropriate level. Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a polymer material that can simultaneously ensure excellent water absorption capacity and biodegradability, and uses thereof. [Means for solving the problem]

[0010] In the present specification, when the measurement temperature and / or pressure affect the physical property value, the physical property means the physical property measured at room temperature and / or normal pressure, unless otherwise specified.

[0011] In the present invention, the term "room temperature" refers to a natural temperature that is neither heated nor cooled, and means, for example, any temperature within the range of about 10°C to 30°C, or a temperature of about 23°C or 25°C.

[0012] In the present invention, the term "normal pressure" refers to a pressure that is not particularly raised or lowered, and means a pressure of the normal atmospheric pressure, for example, a pressure of about 740 mmHg to 780 mmHg.

[0013] In the present specification, when the measurement humidity affects the physical property value, the physical property means the physical property measured at natural humidity without any special adjustment to the measurement temperature and pressure state, unless otherwise specified.

[0014] As used herein, unless otherwise specified, the term "alkyl" or "alkyl group" refers to an alkyl or alkyl group having 1 to 20, 1 to 16, 1 to 12, 1 to 8, or 1 to 4 carbon atoms. Such alkyl or alkyl groups may be linear, branched, or cyclic. Such alkyl or alkyl groups may be optionally substituted with at least one substituent.

[0015] As used herein, unless otherwise specified, the term "alkylene" or "alkylene group" refers to a functional group in which two hydrogen atoms have been removed from an alkane and linked to another object, in which case the two hydrogen atoms have been removed from other carbon atoms of the alkane. Such alkylene or alkylene groups may be alkylene or alkylene groups having 2 to 20, 2 to 16, 2 to 12, 2 to 8, or 2 to 4 carbon atoms. Such alkylene or alkylene groups may be linear, branched, or cyclic. Such alkylene or alkylene groups may be optionally substituted with at least one substituent.

[0016] As used herein, unless otherwise specified, the term "alkylidene" or "alkylidene group" refers to a functional group in which two hydrogen atoms have been removed from an alkane and linked to another object, in which case it refers to a structure in which the two hydrogen atoms have been removed from one carbon atom of the alkane. Such an alkylidene or alkylidene group may be an alkylidene or alkylidene group having 1 to 20, 1 to 16, 1 to 12, 1 to 8, or 1 to 4 carbon atoms. Such an alkylidene or alkylidene group may be linear, branched, or cyclic. Such an alkylidene or alkylidene group may be optionally substituted with at least one substituent.

[0017] In the present invention, the term "hydrogel polymer material" refers to a water-absorbing material comprising cross-linked polymers, and such a material is also simply called a hydrogel.

[0018] As used herein, the term "water-absorbent material" refers to a material that exhibits at least one of the following properties: moisture content, centrifuge retention capacity (CRC), and absorbent capacity under pressure (AUP), as defined herein.

[0019] For example, when the polymer material is an absorbent material, the lower limit of the moisture content of the polymer material may be about 40 wt%, 45 wt%, 50 wt%, or 55 wt%, and the upper limit may be about 70 wt%, 65 wt%, or 60 wt%. The moisture content may be equal to or greater than any of the lower limits, equal to or less than any of the upper limits, or equal to or greater than any of the lower limits but equal to or less than any of the upper limits. The moisture content is the moisture content contained in the polymer material relative to the total weight of the polymer material to be measured and can be calculated based on the weight of the polymer material containing moisture and the weight of the dried polymer material. For example, the moisture content can be calculated based on the weight loss due to evaporation of moisture in the polymer material during the drying process by increasing the temperature of crumb-like polymer using infrared heating. The drying process for measuring the moisture content may include heating from room temperature to about 50°C and then maintaining the temperature at 50°C and vacuum drying for about 6 hours. The polymeric material may exhibit the moisture content before or after crosslinking.

[0020] For example, when the polymeric material is a water-absorbent material, the lower limit of the centrifuge retention capacity (CRC) of the polymeric material according to EDANA (European Disposables and Nonwovens Association) method WSP241.3 may be about 10 g / g, 15 g / g, 20 g / g, 25 g / g, 30 g / g, 35 g / g, 40 g / g, or 45 g / g, and the upper limit may be about 60 g / g, 55 g / g, 50 g / g, 45 g / g, 40 g / g, or 35 g / g. The centrifuge retention capacity (CRC) may be equal to or greater than any of the lower limits, or equal to or less than any of the upper limits, or may be equal to or greater than any of the lower limits but less than any of the upper limits. The polymeric material may exhibit the centrifuge retention capacity before or after crosslinking.

[0021] For example, if the polymeric material is a water-absorbent material, the polymeric material may be classified as EDANA (European Disposables and Nonwovens). The lower limit of the absorbent capacity under pressure (AUP) at 0.7 psi according to the Association of Polyethylene Terephthalate (APE) method WSP242.3 may be about 1.5 g / g, 2 g / g, 2.5 g / g, 3 g / g, 3.5 g / g, 4 g / g, 4.5 g / g, 5 g / g, 5.5 g / g, 6 g / g, 6.5 g / g, 7 g / g, 7.5 g / g, 8 g / g, 8.5 g / g, 9 g / g, 9.5 g / g, 10 g / g, 12 g / g, 14 g / g, 16 g / g, 18 g / g, or 19 g / g, and the upper limit may be about 40 g / g, 35 g / g, 30 g / g, 20 g / g, 15 g / g, 10 g / g, 8 g / g, 6 g / g, or 4 g / g. The absorbent capacity (AUP) may be greater than or equal to any of the lower limits set forth above, or less than or equal to any of the upper limits set forth above, or may be greater than or equal to any of the lower limits but less than or equal to any of the upper limits set forth above. The polymeric material may exhibit the absorbent capacity under pressure before or after crosslinking.

[0022] The polymeric material may be defined as an absorbent material if it exhibits at least one of the properties of moisture content, centrifuge water retention capacity, and absorbency under pressure. The polymeric material may exhibit any one, two or more, or all of the properties of moisture content, centrifuge water retention capacity, and absorbency under pressure.

[0023] As described above, the polymer material of the present invention can exhibit excellent absorbability as well as biodegradability.

[0024] As used herein, a biodegradable material means a material that exhibits the degree of biodegradation defined herein.

[0025] For example, if the polymeric material is biodegradable, the polymeric material may have a lower biodegradability limit of about 60%, 62%, 64%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96%, 98%, or 99%, and an upper biodegradability limit of about 100%, 98%, 96%, 94%, 92%, 90%, 88%, 86%, 84%, 82%, 80%, 78%, or 76%. The biodegradability may be greater than or exceeding any of the lower limits, or less than or equal to any of the upper limits, or may be greater than or exceeding any of the lower limits but less than or equal to any of the upper limits. The biodegradability is measured by the method described in the Examples herein. In one example, the biodegradability of the polymer material may be 50% or more.

[0026] The polymeric material of the present invention may be a biodegradable material in addition to the absorbable material described above.

[0027] The term "polymer material" refers to a material containing a polymer. The polymer may refer to a substance formed by two or more units linked by a covalent bond. In one example, the polymer may refer to a substance having a structure in which two or more units are linked by a covalent bond and having a molecular weight above a certain level. There is no limitation on the range of the molecular weight. In one example, the lower limit of the molecular weight of the polymer may be about 500 g / mol, 1,000 g / mol, 10,000 g / mol, 100,000 g / mol, 1,000,000 g / mol, or 10,000,000 g / mol in weight average molecular weight (Mw), and the upper limit may be about 10,000,000,000 g / mol, 1,000,000,000 g / mol, 100,000,000 g / mol, or 10,000,000 g / mol. The weight average molecular weight may be equal to or greater than any one of the lower limits mentioned above, or equal to or less than any one of the upper limits mentioned above, or may be equal to or greater than any one of the lower limits but equal to or less than any one of the upper limits mentioned above.

[0028] The weight average molecular weight is a value measured by the method described in the examples of this specification.

[0029] In one example, the lower limit of the polymer content in the polymer material may be about 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, or 95 wt%, and the upper limit may be about 100 wt%, 98 wt%, 96 wt%, 94 wt%, 92 wt%, or 90 wt%. The percentage may be equal to or greater than any of the lower limits, or equal to or less than any of the upper limits, or may be equal to or greater than any of the lower limits but equal to or less than any of the upper limits.

[0030] The polymeric materials of the present invention may also include a polysaccharide component.

[0031] The term "polysaccharide component" refers to a polysaccharide or a mixture of polysaccharides. In the case of a mixture of polysaccharides, the mixture may be a mixture of one type of polysaccharide (i.e., a mixture containing two or more molecules of the same type of polysaccharide) or a mixture of two or more types of polysaccharides. In this context, two or more types of polysaccharides refer to polysaccharides of different types, and may include polysaccharides of the same type but with different physical properties such as molecular weight. The polysaccharide component contains only polysaccharides.

[0032] The term "polysaccharide" has the meaning known in the art. Generally, a polysaccharide refers to a polymer molecule in which two or more units are linked by a covalent bond. The covalent bond linking the units is usually a glycosidic bond. A structure in which two units are linked by a covalent bond such as a glycosidic bond is usually called a disaccharide, and unless otherwise specified herein, such disaccharides are also included in the category of polysaccharides.

[0033] The units forming the polysaccharide may be composed of carbon, hydrogen, and oxygen, or may be biomolecules composed of carbon, hydrogen, oxygen, and nitrogen. The term "biomolecule" as used herein is to be interpreted as having the meaning commonly used in the art. Examples of biomolecules generally known in the art include monosaccharides such as glucose, galactose, fructose, and xylose; disaccharides such as sucrose, lactose, maltose, and trehalose; polyols such as sorbitol and mannitol; oligosaccharides such as maltodextrin, dextrin, raffinose, stachyose, and fructooligosaccharides; and / or amino sugars such as glucosamine and N-acetylglucosamine. However, the types of biomolecules used in the present invention are not limited to these.

[0034] When the polymer (e.g., the polysaccharide or polysaccharide component) contained in the polymer material is crosslinked and has absorbent properties, the polymer material is also referred to herein as the hydrogel polymer material or hydrogel. In one example, the polymer material may be in the form of a powder formed through a grinding process or the like.

[0035] In the polymer material of the present invention, the polysaccharide component may be in a cross-linked state. Cross-linking herein refers to a state in which two or more polysaccharide molecules are linked by one or more chemical bonds. The cross-links may be formed by a chemical substance other than the polysaccharide, known as a cross-linking agent, or by a reaction between functional groups contained in the polysaccharide. In this specification, when cross-linking of polysaccharides is achieved by a reaction between functional groups contained in the polysaccharide without the use of a separate cross-linking agent, the cross-linked polysaccharide is also referred to as a self-cross-linked polysaccharide component.

[0036] As used herein, the polymeric material may comprise at least a self-crosslinked polysaccharide component of the above types of crosslinked polysaccharides.

[0037] In one example, the polymeric material may contain a certain amount of the self-crosslinked polysaccharide component based on the total weight of the polymeric material. For example, the lower limit of the percentage of the self-crosslinked polysaccharide component in the polymeric material may be about 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, or 95 wt%, and the upper limit may be about 100 wt%, 98 wt%, 96 wt%, 94 wt%, 92 wt%, or 90 wt%. The percentage may be equal to or greater than any of the lower limits, or equal to or less than any of the upper limits, or may be equal to or greater than any of the lower limits but less than any of the upper limits.

[0038] In another example, the proportion of the crosslinker crosslinking the polysaccharide components in the polymer material may be limited to a certain content or less. Here, the crosslinker refers to a substance that forms chemical bonds connecting the polysaccharide components, but is not a polysaccharide. For example, the upper limit of the proportion of the crosslinker in the polymer material may be approximately 10 wt%, 9 wt%, 8 wt%, 7 wt%, 6 wt%, 5 wt%, 4 wt%, 3 wt%, 2 wt%, 1 wt%, 0.5 wt%, 0.1 wt%, 0.05 wt%, 0.01 wt%, 0.005 wt%, or 0.001 wt%, and the lower limit may be approximately 0 wt%. The proportion of the crosslinker may be less than or equal to any of the above upper limits, or may be greater than or exceeding any of the above lower limits but less than or equal to any of the above upper limits.

[0039] In the present invention, crosslinking of polysaccharides is performed without using a crosslinking agent or with the amount of crosslinking agent used minimized. Using a crosslinking agent other than polysaccharides may reduce the biodegradability of the polymer material. However, generally, when a crosslinking agent is not used, the crosslinking efficiency of polysaccharides decreases, making it difficult to obtain a polymer material with desired properties (e.g., absorption properties). In the present invention, by using a polysaccharide having at least one of the properties of the polysaccharides described below and / or by applying the self-crosslinking method described below, a self-crosslinked polymer material can be provided that has excellent biodegradability and excellent physical properties (e.g., absorption capacity).

[0040] For example, the self-crosslinked polysaccharide may include amylose and amylopectin. As is known, amylopectin and amylose are types of polysaccharides found mainly in plants, and among polysaccharides, starch is composed of amylose and amylopectin. Amylose is composed of glucose molecules linked by α(1→4) glycosidic bonds and has a linear structure, while amylopectin has relatively short and highly branched chains. Amylose crystallizes more easily than amylopectin, and amylopectin has a higher solubility in water than amylose.

[0041] The ratio of amylose to amylopectin in the polysaccharide component and the molecular weight of the polysaccharide component may be significantly related to the self-crosslinking efficiency and thus the absorbability and biodegradability of the polymeric material.

[0042] As the proportion of amylopectin in the polysaccharide component decreases and the proportion of amylose increases, the biodegradability of the material increases, but the absorption capacity tends to decrease slightly.Furthermore, as the molecular weight of the polysaccharide component increases, the biodegradability of the material decreases, but the absorption capacity tends to increase.

[0043] For example, the polymeric material or polysaccharide component may have F in a predetermined range according to formula 1 below:

[0044]

number

[0045] In Equation 1, P is the proportion of amylopectin in the polysaccharide component, M is the proportion of amylose in the polysaccharide component, and Mw is the weight average molecular weight of the polysaccharide component.

[0046] In Equation 1, F is a factor that indicates the amount of amylose and amylopectin in the polysaccharide component and the molecular weight of the polysaccharide component. For example, the value of F increases as the molecular weight of the polysaccharide component increases and / or the proportion of amylopectin in the polysaccharide component increases.

[0047] The polysaccharide component, in which the ratio and molecular weight of amylose and amylopectin are controlled so that the value of F falls within a predetermined range, may be efficiently crosslinked to form a material with excellent absorbability and biodegradability.

[0048] In Equation 1, P and M are the proportions of amylopectin and amylose measured by the method described in the Examples section of this specification, and their units are %.

[0049] In formula 1, Mw is the weight average molecular weight of the polysaccharide component, which is measured by the method described in the Examples section of the present specification, and its unit is g / mol.

[0050] In Formula 1, the lower limit of F may be about 4, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, 7.0, 7.2, 7.4, 7.6, 7.8, 8.0, or 8.2, and the upper limit may be about 20, 18, 16, 14, 12, 10, 9, 8, 7, 6, or 5. F may be equal to or greater than any of the lower limits mentioned above, or may be equal to or greater than any of the upper limits mentioned above, or may be equal to or greater than any of the lower limits but equal to or less than any of the upper limits mentioned above.

[0051] Within these ranges, the polysaccharide component may be efficiently cross-linked to form a polymeric material with excellent absorbability and biodegradability.

[0052] In Formula 1, the ranges of Mw, M and P may be adjusted to appropriate levels.

[0053] For example, the lower limit of Mw in Formula 1 is 200,000 g / mol, 250,000 g / mol, 300,000 g / mol, 350,000 g / mol, 400,000 g / mol, 450,000 g / mol, 500,000 g / mol, 550,000 g / mol, 600,000 g / mol, 650,000 g / mol, 700,000 g / mol, 750,000 g / mol, 800,000 g / mol, 850,000 g / mol, 900,000 g / mol, 950,000 g / mol, 1,000,000 g / mol, 1,500,000 g / mol, 200,000 g / mol, 300,000 g / mol, 4 ...00,000 g / mol, 600,000 g / mol, 700,000 g / mol, 800,000 g / mol, 850,000 g / mol, 900,000 g ,000,000g / mol,2,500,000g / mol,3,000,000g / mol,3,500,000g / mol,4,000,000g / mol,4,500,000g / mol,5,000,000g / mol,5,500,000g / mol,6,000, 000g / mol, 6,500,000g / mol, 7,000,000g / mol, 7,500,000g / mol, 8,000,000g / mol, 8,500,000g / mol, 9,000,000g / mol, 9,500,000g / mol, 10,000,000g / mol, 20,000,000g / mol, 30,000,000g / mol, 40,000,000g / mol, 50,000,000g / mol, 60,000,000g / mol, 70,000,000g / mol, 80,000,000g / mol, 90,000,0 00g / mol, 100,000,000g / mol, 110,000,000g / mol, 120,000,000g / mol, 130,000,000g / mol, 140,000,000g / mol, 150,000,000g / mol, 160,000,000g / mol The upper limit may be 10,000,000,000 g / mol, 5,000,000,000 g / mol, 1,000,000,000 g / mol, 900,000,000 g / mol, 800,000,000 g / mol, 700,000,000 g / mol, 600,000,000 g / mol, 500,000,000 g / mol, 400,000,000 g / mol, 300,000,000 g / mol, 200,000,000 g / mol, 150,000,000g / mol, 100,000,000g / mol, 90,000,000g / mol, 80,000,000g / mol, 70,000,000 / mol, 60,000,000g / mol, 50 ,000,000g / mol, 40,000,000 / mol, 30,000,000 / mol, 20,000,000g / mol, 10,000,000g / mol, 9,000,000g / mol, 8,000 The Mw may be on the order of 1,000 g / mol, 7,000,000 g / mol, 6,000,000 g / mol, 5,000,000 g / mol, 4,000,000 g / mol, 3,000,000 g / mol, 2,000,000 g / mol, 1,000,000 g / mol, 900,000 g / mol, 800,000 g / mol, 700,000 g / mol, 600,000 g / mol, or 500,000 g / mol. The Mw may be greater than or exceeding any of the lower limits recited above, or less than or equal to any of the upper limits recited above, or may be greater than or exceeding any of the lower limits recited above, but less than or equal to any of the upper limits recited above.

[0054] In Formula 1, the lower limit of P may be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80%, and the upper limit may be about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, or 20%. P may be equal to or greater than any of the lower limits, or may be equal to or greater than any of the upper limits, but equal to or less than any of the upper limits.

[0055] In Formula 1, the lower limit of M may be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80%, and the upper limit may be about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, or 20%. M may be equal to or greater than any of the lower limits mentioned above, or may be equal to or greater than any of the upper limits mentioned above, but equal to or less than any of the upper limits mentioned above.

[0056] In one example, the sum of M and P in the polysaccharide component may be 100%.

[0057] In one example, when the polysaccharide of the polysaccharide component is a modified polysaccharide (described below), i.e., a polysaccharide having an acidic group such as a carboxyl group introduced therein by maleation or carboxyalkylation, the functional group introduced into the modified polysaccharide may be introduced into either the amylose or the amylopectin, or may be introduced into both. The reaction to introduce the functional group (described below) may occur in both the amylose and the amylopectin, but more efficient modification is possible when the amylopectin content is higher than the amylose content.

[0058] As the polysaccharide component, any suitable type may be selected from the polysaccharides described above, as long as it contains at least the polysaccharide containing amylose and amylopectin. A polysaccharide component may be formed by combining one or more known polysaccharides so that F in the above formula (1) is 4 or greater, and this polysaccharide component may be applied to the polymer material.

[0059] In the present invention, the self-crosslinking of the polysaccharide may be carried out using so-called acidic polysaccharides, which are known to be polysaccharides having acidic groups, such as carboxylic groups, phosphate groups, phosphite groups, and / or sulfuric ester groups, or salts thereof.

[0060] For proper self-crosslinking, the degree of substitution of the acidic polysaccharide or acidic polysaccharide component may be adjusted. The degree of substitution is an indicator of the amount of the acidic group present in the acidic polysaccharide or polysaccharide component, and may be, for example, a value determined before the polysaccharide or polysaccharide component realizes the crosslinked structure.

[0061] For example, the lower limit of the degree of substitution may be about 0.4, 0.45, 0.5, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, or 1, and the upper limit may be about 2.5, 2, 1.5, 1.1, 1.05, 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, or 0.6. The degree of substitution may be equal to or greater than any of the lower limits, or equal to or less than any of the upper limits, or may be equal to or greater than any of the lower limits but equal to or less than any of the upper limits. Within this range of degree of substitution, cross-linking of the polysaccharide may be effectively performed, and the physical properties (e.g., absorbency and / or biodegradability) of the resulting polymer material may be stably ensured. A high degree of substitution is advantageous in terms of absorbency because the polysaccharide or polysaccharide component contains many acidic groups, which are hydrophilic functional groups. However, an excessive number of acidic groups may excessively promote the crosslinking reaction, resulting in a decrease in absorbency after crosslinking. Therefore, an appropriate degree of substitution may be selected taking these points into consideration.

[0062] As used herein, the degree of substitution is an index indicating the degree of acidic groups present in a polysaccharide or polysaccharide component. For example, it is a value indicating the degree to which functional groups such as hydroxyl groups present in each unit contained in a polysaccharide or polysaccharide component have been substituted with a specific acidic group (e.g., the carboxyl group), and is an average value for each unit present in the polysaccharide. For example, if the unit is a glucose unit, the unit before modification has three hydroxyl groups. Therefore, if all of the hydroxyl groups are substituted with the functional group of formula (1), the degree of substitution for the unit is 3. However, since the degree of substitution of a polysaccharide is an average value of the degree of substitution of each unit present in the polysaccharide, for example, if a polysaccharide containing five glucose units has degrees of substitution of 1, 0, 2, 3, and 1, the degree of substitution of the polysaccharide is an average value of 1.4. Such degrees of substitution are determined based on the degree of substitution of the polysaccharide. 1 This can be confirmed through H NMR analysis. 1 The hydroxyl groups present in the polysaccharide and the substituted functional groups can be quantified through H NMR analysis, so the degree of substitution can be confirmed. 1 The degree of substitution can be calculated based on the results of H NMR analysis. 1 Methods for quantifying functional groups through 1 H NMR analysis are well known.

[0063] In the present invention, the self-crosslinking of the polysaccharide may be carried out using, for example, a polysaccharide or polysaccharide component having a carboxyl group as an acidic group among the above-mentioned acidic polysaccharides or acidic polysaccharide components. Since polysaccharides themselves contain hydroxyl groups, the self-crosslinking may be carried out by esterifying the hydroxyl group contained in any of the polysaccharide molecules with the carboxyl group contained in the acidic polysaccharide.

[0064] The type of polysaccharide having a carboxyl group is not particularly limited. For example, the self-crosslinking may be performed using a polysaccharide that itself has a carboxyl group, such as so-called CMC (carboxylmethyl cellulose), or a polysaccharide into which a carboxyl group has been introduced through a process such as maleation or carboxyalkylation.

[0065] The self-crosslinked polysaccharide component may comprise polymeric chains comprising monosaccharide units linked by glycosidic bonds (i.e., crosslinked polysaccharide chains) and crosslinks connecting the polymeric chains.

[0066] In this case, the cross-linking bond may be linked to the monosaccharide unit.

[0067] The cross-linked bond may be a bond represented by the following formula 1.

[0068] [ka]

[0069] In Chemical Formula 1, X1 is an oxygen atom or NR 11 and R 11 is a hydrogen atom, an alkyl group or an alkylcarbonyl group, L1 is an alkylene group, an alkylidene group or a bond of the following formula 2, and L2 is a single bond or -(CH2)-O-.

[0070] [ka]

[0071] X1, shown on the leftmost side in Formula 1, may be directly linked to a monosaccharide unit of the polymer chain.

[0072] In the formula 1, when X1 is an oxygen atom, starch or the like is used as the crosslinker, and NR11 In this case, chitosan or chitin is used as a polysaccharide for the crosslinking.

[0073] R 11 The alkyl group may be an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, or a methyl group, and such an alkyl group may be linear, branched, or cyclic, and may optionally be substituted with at least one substituent.

[0074] In Chemical Formula 1, when L2 is a single bond, L2 does not exist. That is, when L2 is present in Chemical Formula 1, L2 is directly linked to a monosaccharide unit of the polymer chain, and when L2 is a single bond, the oxygen atom on the left side of L2 in Chemical Formula 1 may be directly linked to the monosaccharide unit.

[0075] When the self-crosslinking of polysaccharides is carried out by polysaccharides that themselves have carboxyl groups, such as CMC (carboxylmethyl cellulose), or polysaccharides that have carboxyl groups introduced by carboxyalkylation, L1 in Chemical Formula 1 may generally be an alkylene group or an alkylidene group. When L1 in Chemical Formula 1 is a functional group represented by Chemical Formula 2, self-crosslinking is carried out by carboxyl groups introduced by maleation.

[0076] When L1 in Chemical Formula 1 is Chemical Formula 2, one of the carbon atoms of the carbonyl group in Chemical Formula 2 is linked to X1 on the left side of L1 in Chemical Formula 1, and the carbon atom on the right side of the carbon-carbon double bond is linked to the carbon atom of the carbonyl group on the right side of L1.

[0077] There may be at least one bond of formula (1) in the self-crosslinked polysaccharide component.

[0078] The type of the monosaccharide unit is not particularly limited, and may be any monosaccharide unit that normally constitutes a polysaccharide, such as a glucose unit, a glucosamine unit, or an N-acetylglucosamine unit.

[0079] Such monosaccharide units typically contain a ring structure containing carbon and oxygen atoms. The ring structure of the monosaccharide unit is typically a six-membered ring structure (containing only five carbon atoms and one oxygen atom), but may be a ring structure with six or more members. When the ring structure is six or more members, the ring atoms may be carbon atoms or heteroatoms such as oxygen or nitrogen atoms.

[0080] In the case of a self-crosslinking structure, the bond of formula (1) may be directly connected to the carbon atom of the ring structure of the monosaccharide unit as described above, or may be connected via a methylene group (-CH2-).

[0081] At least one or all of the leftmost X1 and the rightmost oxygen atom in Chemical Formula 1 (when L2 is a single bond, it means the oxygen atom connected to the right side of the carbonyl group, and when it is not a single bond, it means the oxygen atom of -(CH2)-O-) may be directly connected to a carbon atom in the ring structure or may be connected via a methylene group (-CH2-).

[0082] In the above, being linked via a methylene group (-CH2-) means that only the methylene group (-CH2-) exists between the leftmost X1 in the above formula 1 or the rightmost oxygen atom in the above formula 1 (when L2 is not a single bond, the oxygen atom of -(CH2)-O-) and the carbon atom of the ring structure.

[0083] In this case, more specifically, the polysaccharide component may contain a unit represented by the following formula 3.

[0084] [ka]

[0085] In Chemical Formula 3, R1 is a hydroxy group, an amino group, -L5-C(=O)-OH, -L5-C(=O)-O - Or a functional group of the following formula 4, where R3 is a hydroxy group, -L5-C(=O)-OH, -L5-C(=O)-O - or a functional group of the following formula 4, wherein either L3 or L4 is a single bond and the other is CHR2, and R2 is a hydroxy group, -L5-C(=O)-OH, -L5-C(=O)-O - Or a functional group of the following formula 4, wherein L5 is an alkylene group or an alkylidene group, and any of R1 to R3 is an oxygen atom of the bond of formula 1 (excluding the oxygen atom present in the carbonyl group).

[0086] [ka]

[0087] In Chemical Formula 4, X2 is an oxygen atom or NR 11 and R 11 is a hydrogen atom, an alkyl group or an alkylcarbonyl group, M1 is hydrogen or a metal, and when M1 is the metal, the O-M1 bond is an ionic bond.

[0088] In Chemical Formula 3, when R1 is an amino group, the unit is a glucosamine unit or an N-acetylglucosamine unit. In this case, the amino group may be optionally substituted with at least one substituent. In this case, examples of the substituent include an alkyl group or an alkylcarbonyl group. In this case, the alkyl group may be an alkyl group having 1 to 20, 1 to 16, 1 to 12, 1 to 8, or 1 to 4 carbon atoms, or a methyl group. Such an alkyl group may be linear, branched, or cyclic, and may be optionally substituted with at least one substituent.

[0089] -L5-C(=O)-OH or -L5-C(=O)-O in Chemical Formula 3 -The functional group of formula (I) may be, for example, a carboxyl group introduced by carboxyalkylation or a functional group obtained by ionizing the carboxyl group, and formula (II) is a functional group introduced by malonation.

[0090] Such functional groups are introduced to participate in the above-mentioned self-crosslinking reaction to form crosslinks, but not all of the introduced functional groups may participate in the crosslinking reaction, and in that case, some functional groups may remain.

[0091] In the above, when either L3 or L4 is a single bond, it means that either L3 or L4 is absent. For example, when L3 is absent, the carbon atoms connected to the left and right sides of L3 in Chemical formula 3 are directly connected, and when L4 is absent, the carbon atoms connected to the left and right sides of L4 in Chemical formula 3 are directly connected.

[0092] In the above, when either L3 or L4 is CHR2, it means that either L3 or L4 in Chemical Formula 3 is a carbon atom, and the carbon atom is substituted with a substituent R2.

[0093] In Chemical Formula 3, when any of R1 to R3 is an oxygen atom of the bond of Chemical Formula 1 (excluding the oxygen atom present in the carbonyl group), it means that any of R1 to R3 is an oxygen atom of the bond of Chemical Formula 1 linking the polysaccharides, and in this case, the oxygen atom means either the leftmost oxygen atom or the rightmost oxygen atom of Chemical Formula 1 (when L2 is a single bond, it means the oxygen atom linked to the right of the carbonyl group, and when it is not a single bond, it means the oxygen atom of -(CH2)-O-).

[0094] In Chemical Formula 4, when X2 is an oxygen atom, starch or the like is maleated as a polysaccharide, and NR 11 In the case of R, chitosan or chitin as a polysaccharide is maleated. 11The alkyl group may be an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, or a methyl group, and such an alkyl group may be linear, branched, or cyclic, and may optionally be substituted with at least one substituent.

[0095] As described above, the self-crosslinking structure can be realized by esterifying acidic polysaccharides, particularly polysaccharides having carboxyl groups.

[0096] As the acidic polysaccharide, a polysaccharide having a carboxyl group itself, such as CMC (carboxylmethyl cellulose), or a polysaccharide having a carboxyl group introduced therein through a process such as maleation or carboxyalkylation can be used. However, a polysaccharide having a carboxyl group introduced therein through a modification process may also be used to achieve the above-mentioned degree of substitution and for efficient self-crosslinking.

[0097] There are no particular limitations on the method for introducing carboxyl groups into polysaccharides. For example, a so-called maleation process may be performed to introduce functional groups such as those shown in Chemical Formula 4. This process involves reacting a polysaccharide with an unsaturated dicarboxylic acid or its anhydride to substitute the hydroxyl groups present in the monomers of the polymer with the functional groups. Examples of the dicarboxylic acid or its anhydride include, but are not limited to, maleic acid or maleic anhydride, and salts of maleic acid may also be used. Methods for performing the maleation process are well known.

[0098] The carboxyalkylation step may be carried out by reacting a polysaccharide with an alkanoic acid or a haloalkanoic acid, or a salt of the alkanoic acid or haloalkanoic acid. As is well known, an alkanoic acid is an aliphatic acid derived from an alkane, and a haloalkanoic acid refers to an alkanoic acid in which at least one hydrogen atom is substituted with a halogen atom (e.g., chlorine, fluorine, or bromine). In this specification, the alkanoic acid, haloalkanoic acid, salt of an alkanoic acid, and / or salt of a haloalkanoic acid used in the carboxyalkylation step are also referred to as a treating agent.

[0099] The alkanoic acid or haloalkanoic acid used as the treatment agent may be, for example, an alkanoic acid or haloalkanoic acid having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, and acetic acid or chloroacetic acid may be typically used.

[0100] In addition, the salt of the haloalkanoic acid or alkanoic acid may be an alkali metal salt or alkaline earth metal salt of a haloalkanoic acid or alkanoic acid having the above carbon number.

[0101] Acidic groups (such as carboxyl groups) may be introduced into the polysaccharide by reacting the polysaccharide with the treating agent under appropriate conditions.

[0102] The step of introducing the acidic group may be carried out by a known method, and if necessary, an additional step may be carried out or the conditions of the step may be adjusted for efficient progress of the carboxyalkylation step.

[0103] For example, the process may be performed on a mixture in which the treatment agent and hydroxide are dispersed in a solvent. The solvent may be, for example, an aqueous solvent such as water. The water may be tap water, distilled water, deionized water, or purified water. The hydroxide may be ammonium hydroxide or a metal hydroxide, and the metal hydroxide may be, but is not limited to, sodium hydroxide, potassium hydroxide, or lithium hydroxide.

[0104] In the reaction to the mixture, for example, it is predicted that first a gelatinization reaction of the polysaccharides occurs within the mixture, and then a carboxyl group or the like is introduced by the treating agent.

[0105] The reaction may be carried out, for example, while maintaining the torque of the reactor containing the mixture at a constant level after the gelatinization, thereby allowing the introduction of a suitable carboxyl group.

[0106] For example, gelatinization occurs when the mixture is mixed in a mixer capable of mixing the components by rotation, such as an internal mixer. During the gelatinization process, thermal energy is generated in the reactor due to the load induced by gelatinization, resulting in an increase in torque and temperature. Typically, when the torque and temperature in the reactor increase and reach a certain level, a period in which they remain constant occurs, and the point at which this period occurs is generally considered to be the point at which gelatinization is complete. By maintaining the torque at an appropriate level at and / or after the point at which gelatinization is complete, a polysaccharide having a desired degree of substitution and capable of efficiently undergoing self-crosslinking can be obtained.

[0107] In one example, the lower limit of the torque in the reactor at and / or after the completion of gelatinization may be about 5 Nm, 5.5 Nm, 7 Nm, 7.5 Nm, or 8 Nm, and the upper limit may be about 20 Nm, 19 Nm, 18 Nm, 16 Nm, 15 Nm, 14 Nm, 13 Nm, 12 Nm, 11 Nm, 10 Nm, or 9 Nm. The torque may be equal to or greater than any of the lower limits, or equal to or greater than any of the upper limits, or may be equal to or greater than any of the lower limits but equal to or less than any of the upper limits. Maintaining the torque within this range prevents excessive evaporation of the solvent and maintains stable workability while maintaining the carboxyl group substitution efficiency within a desired range.

[0108] To maintain the torque, the ratio of the solvent in the mixture may be controlled. For example, the lower limit of the ratio of the solvent in the mixture may be about 0.45, 0.5, 0.6, or 0.7 times the weight of the polysaccharide present in the mixture, and the upper limit may be about 0.75, 0.74, 0.73, or 0.72 times the weight of the polysaccharide present in the mixture. The ratio may be equal to or greater than any of the lower limits, or equal to or less than any of the upper limits, or may be equal to or greater than any of the lower limits but less than any of the upper limits. Maintaining the solvent ratio within the above range prevents excessive evaporation of the solvent while maintaining the carboxyl group substitution efficiency within a desired range, thereby maintaining a torque that allows stable workability.

[0109] In the reaction process, it is appropriate to use substantially only the aqueous solvent (e.g., water) as the solvent. In general, in addition to the aqueous solvent, alcohols, ketones, 1,4-dioxane, dimethylformamide, dimethyl sulfoxide, etc. may also be used as the solvent for carboxyalkylation, but if such solvents are used, the desired reaction may not proceed.

[0110] The mixture may be substantially free of other solvents other than the aqueous solvent (e.g., water). In this case, "substantially free of other solvents" means that the content of other solvents in the mixture other than the aqueous solvent (e.g., water) may be approximately 10 wt%, 9 wt%, 8 wt%, 7 wt%, 6 wt%, 5 wt%, 4 wt%, 3 wt%, 2 wt%, 1 wt%, 0.5 wt%, 0.1 wt%, 0.05 wt%, 0.01 wt%, 0.005 wt%, or 0.001 wt%, with the lower limit being approximately 0 wt%. The percentage may be less than or equal to any of the upper limits, or may be greater than or exceed any of the lower limits but still be less than or equal to any of the upper limits.

[0111] The ratio of hydroxide to treating agent within the mixture may also be controlled.

[0112] For example, the lower limit of the hydroxide ratio in the mixture may be about 0.5, 0.6, or 0.7 equivalents, and the upper limit may be about 1.5, 1.15, 1.1, 1, 0.9, or 0.8 equivalents. The equivalents may be less than or equal to any of the upper limits, or may be greater than or equal to any of the lower limits but less than or equal to any of the upper limits. The equivalents can be calculated using the formula A / B, where A is the number of moles of hydroxide present in the mixture and B is calculated using the formula C / 162.14, where C is the weight (units: g) of polysaccharide in the mixture. 162.14 is the molar mass (g / mol) of an anhydroglucose unit. Typically, polysaccharides contain the anhydroglucose unit or a derivative thereof, or a unit with a molar mass similar thereto. Therefore, in the present invention, if the amount of polysaccharide used to calculate the equivalent weight is representatively applied to the above formula C / 162.14, the reaction can be carried out according to the purpose by defining the equivalent weight within the above range according to this application method. Maintaining the amount of hydroxide used within the above range allows the substitution efficiency of carboxyl groups, etc., to be maintained within the desired range, while stably maintaining reaction efficiency and workability and suppressing unwanted side reactions.

[0113] The lower limit of the proportion of the treating agent in the mixture may be about 0.5, 0.6, or 0.7 equivalents, and the upper limit may be about 1.5, 1.15, 1.1, 1, 0.9, or 0.8 equivalents. The equivalent may be less than or equal to any of the aforementioned upper limits, or may be greater than or equal to any of the aforementioned lower limits but less than or equal to any of the aforementioned upper limits. The equivalent may be calculated using the formula D / B, where D is the number of moles of the treating agent present in the mixture and B is the same as in the formula for calculating the hydroxide equivalent. Maintaining the amount of treating agent used within the above ranges allows for maintaining the substitution efficiency of carboxyl groups and the like within a desired range, while stably maintaining reaction efficiency and workability and suppressing unwanted side reactions.

[0114] The ratio (A / D) of the moles of the hydroxide (A) to the moles of the treating agent (D) in the mixture may have a lower limit of about 0.5, 0.6, 0.7, 0.8, 0.9, or 0.95, and an upper limit of about 1.5, 1.4, 1.3, 1.2, 1.1, or 1.05. The ratio may be less than or equal to any of the above upper limits, or may be greater than or equal to any of the above lower limits but still be less than or equal to any of the above upper limits. Maintaining the above ratio allows for the production of a stable self-crosslinkable polysaccharide while maintaining the carboxyl group substitution efficiency within a desired range, thereby stably maintaining reaction efficiency and workability and suppressing unwanted side reactions.

[0115] In the reaction, the mixture may be present in a reactor in a predetermined ratio. For example, the lower limit of the volume ratio of the mixture in the reactor may be about 70%, 75%, 76%, or 77% based on the total volume of the reactor, and the upper limit may be about 95%, 94%, 93%, or 92%. The ratio may be less than or equal to any of the upper limits, or may be greater than or equal to any of the lower limits but less than or equal to any of the upper limits. Maintaining the ratio may stably maintain the torque in the reactor, maintain the substitution efficiency of carboxyl groups, etc., within a desired range, produce a stable self-crosslinkable polysaccharide component, stably maintain reaction efficiency and workability, and suppress unwanted side reactions.

[0116] During the reaction, the temperature in the reactor may be maintained at a constant level at and / or after the completion of the gelatinization. For example, the lower limit of the temperature may be about 90°C, 92°C, 94°C, or 96°C, and the upper limit may be about 110°C, 105°C, 100°C, 99°C, 98°C, or 97°C. The temperature may be equal to or less than any of the upper limits, or may be equal to or greater than any of the lower limits but still be equal to or less than any of the upper limits. Maintaining the temperature at the above range may stably maintain the torque in the reactor, maintain the carboxyl group substitution efficiency within a desired range, produce a stable self-crosslinkable polysaccharide, stably maintain reaction efficiency and workability, and suppress unwanted side reactions.

[0117] As described above, the carboxyalkylation may be carried out using a reactor capable of mixing the mixture by rotation. The specific type of reactor is not particularly limited, and for example, an internal mixer such as a two-roll mixer, a Banbury mixer, or an intermix mixer may be used. The torque and temperature may also be measured using sensors attached to such a mixer.

[0118] The mixing time is not particularly limited and may be controlled to a level that achieves desired gelatinization and carboxyalkylation. For example, the lower limit of the mixing time may be about 5, 7, 9, or 10 minutes, and the upper limit may be about 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 14, 13, 12, 11, or 10 minutes. The mixing time may be less than or equal to any of the upper limits, or may be greater than or equal to any of the lower limits but less than or equal to any of the upper limits.

[0119] The rotation speed of the mixer may be controlled to maintain a desired torque and / or temperature. The lower limit of the rotation speed may be, for example, about 30 rpm, 35 rpm, 40 rpm, 45 rpm, or 50 rpm, and the upper limit may be about 100 rpm, 95 rpm, 90 rpm, 85 rpm, 80 rpm, 75 rpm, 70 rpm, 65 rpm, 60 rpm, 55 rpm, or 50 rpm. The rotation speed may be less than or equal to any of the upper limits, or may be greater than or equal to or exceeding any of the lower limits while being less than or equal to any of the upper limits.

[0120] Carboxyalkylation is carried out through the above process to obtain the desired polysaccharide.

[0121] After the carboxyl group is introduced into the polysaccharide through the reaction, the self-crosslinking step described below may be carried out immediately, or if necessary, the self-crosslinking step may be carried out after the polysaccharide is recovered.

[0122] The recovery of the polysaccharide may include dissolving the reaction product in water and precipitating it using an organic solvent such as alcohol, or various other methods may be used.

[0123] After the acidic polysaccharide is obtained by the above method, it can be self-crosslinked. The method for self-crosslinking is not particularly limited, but for efficient self-crosslinking, the acidic polysaccharide may be dispersed in a solvent and then maintained at a predetermined pH range.

[0124] In the above process, the solvent may be the above-mentioned aqueous solvent, for example, water, and the water may be tap water, distilled water, deionized water, purified water, or the like.

[0125] During self-crosslinking, it is appropriate to use substantially only the aqueous solvent (e.g., water) as the solvent. Therefore, the solvent used during self-crosslinking may be substantially free of other solvents other than the aqueous solvent (e.g., water). In this case, "substantially free of other solvents" means that the content of other solvents other than the aqueous solvent (e.g., water) in the solvent is approximately 10 wt%, 9 wt%, 8 wt%, 7 wt%, 6 wt%, 5 wt%, 4 wt%, 3 wt%, 2 wt%, 1 wt%, 0.5 wt%, 0.1 wt%, 0.05 wt%, 0.01 wt%, 0.005 wt%, or 0.001 wt%, and the lower limit is approximately 0 wt%. The percentage may be less than or equal to any of the upper limits, or may be greater than or exceed any of the lower limits, but may be less than or equal to any of the upper limits.

[0126] The amount of the solvent used in the above process may be 5 to 15 times the weight of the polysaccharide used. The dissolution of the polysaccharide in the solvent may be carried out under normal temperature and pressure conditions, but is not limited thereto.

[0127] Self-crosslinking may be achieved by dissolving the polysaccharide in the solvent and maintaining the pH at a certain level. If necessary, additional steps may be carried out to promote self-crosslinking, such as a stirring step.

[0128] The lower limit of the pH maintained during the process may be about 4, 4.5, 5, 5.5, or 6, and the upper limit may be about 10, 9.5, 9, 8.5, 8, 7.5, 7, or 6.5. The pH may be less than or equal to any of the upper limits mentioned above, or may be greater than or equal to or exceeding any of the lower limits but less than or equal to any of the upper limits mentioned above. By maintaining such a pH range, the desired self-crosslinking can be effectively achieved.

[0129] The method for maintaining the pH within the above range is not particularly limited. If the pH within the above range is achieved by adding an acidic polysaccharide, self-crosslinking can be performed under that condition. If the desired pH is not achieved, the pH can be adjusted by adding an appropriate acid or base taking the desired pH into consideration. In this case, the base may be, for example, the hydroxide used in the carboxyalkylation, and the acid may be, for example, hydrochloric acid or sulfuric acid, but is not limited thereto.

[0130] A catalyst may be added during the reaction, if necessary. For example, an ester catalyst that promotes the reaction between a carboxyl group and a hydroxyl group may be added. Examples of such catalysts include, but are not limited to, 4-methylaminopyridine, magnesium acetate, tetra-n-butyl titanate, lead acetate, sodium acetate, potassium acetate, antimony trioxide, and / or N-methylimidazole. The catalyst may be added in a catalytic amount, for example, in a ratio of 0.1 to 5 moles per mole of polysaccharide used in the reaction. The lower limit of the catalyst use ratio may be about 0.1 moles, 0.5 moles, 1 mole, or 2 moles, and the upper limit may be about 5 moles, 4.5 moles, 4 moles, or 3.5 moles. The ratio may be less than or equal to any of the above upper limits, or may be greater than or exceed any of the above lower limits but less than or equal to any of the above upper limits.

[0131] The reaction may be carried out in the presence of a heat stabilizer, if necessary. Suitable heat stabilizers include organic or inorganic phosphorus compounds such as phosphoric acid, organic esters of phosphoric acid, phosphorous acid, or organic esters of phosphorous acid, such as phosphoric acid, alkyl phosphates, or aryl phosphates, which are commercially known as heat stabilizers.

[0132] The reaction may be carried out in the presence of additives such as a thickener, a plasticizer, a storage stabilizer and / or an antioxidant, if necessary.

[0133] The crosslinking reaction may be carried out at a predetermined temperature. For example, the lower limit of the temperature at which the reaction is carried out may be about 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, or 120°C, and the upper limit may be about 300°C, 280°C, 260°C, 240°C, 220°C, 200°C, 180°C, 160°C, 140°C, 130°C, 125°C, or 125°C. The temperature may be equal to or less than any of the above upper limits, or may be equal to or greater than any of the above lower limits but equal to or less than any of the above upper limits. The reaction temperature may be controlled by, for example, supplying hot air, irradiating with infrared rays, irradiating with ultrashort waves, or irradiating with ultraviolet rays.

[0134] The reaction time is not particularly limited, and for example, the lower limit of the reaction time may be about 20, 40, 60, 80, 100, or 120 minutes, and the upper limit may be about 500, 480, 460, 440, 420, 400, 380, 360, 340, 320, 300, 280, 260, 240, 220, 200, or 180 minutes. The reaction time may be less than or equal to any of the upper limits, or may be greater than or equal to or exceeding any of the lower limits but less than or equal to any of the upper limits.

[0135] The above method results in the desired self-crosslinked polysaccharide component.

[0136] The polymer material may further include a crosslinking agent reacted with the self-crosslinked polysaccharide component along with the self-crosslinked polysaccharide component. Such a treatment agent may be introduced by reacting the self-crosslinked polysaccharide component with the crosslinking agent. That is, the polymer material of the present invention may be provided in a state in which two or more polysaccharide molecules are crosslinked by the self-crosslinking described above, and then additional crosslinking is performed by applying the crosslinking agent. Such additional crosslinking is introduced to improve the gel strength of the self-crosslinked polysaccharide component and to improve absorbency under load (AUP) and / or saline flow conductivity.

[0137] The additional cross-linking agent may be introduced by, for example, subjecting the self-cross-linked polysaccharide component to a process such as grinding to turn it into a powder, and then reacting the cross-linking agent with the surface of the powder. In this case, the polymer material may contain the self-cross-linked polysaccharide component in particulate form and the cross-linking agent bound to the surface of the particles. In such a case, the particle size is not particularly limited and may be controlled to an appropriate size depending on the application.

[0138] Such a crosslinking agent may have two or more functional groups capable of reacting with functional groups (such as hydroxyl groups, amino groups, or carboxyl groups) of the polysaccharide component. The crosslinking agent may have 2 to 10, 2 to 9, 2 to 8, 2 to 7, 2 to 6, 2 to 5, 2 to 4, or 2 to 3 functional groups capable of reacting with functional groups (such as hydroxyl groups, amino groups, or carboxyl groups) of the polysaccharide component, or may have 2 or 3 functional groups.

[0139] Applicable types of crosslinking agents include at least one selected from the group consisting of multifunctional epoxy compounds, epoxysilane compounds, aminosilane compounds, epichlorohydrin, aldehyde compounds such as formaldehyde and glutaraldehyde, acyl chloride, carbonate, diamine, diol, carbon disulfide, phosphoryl chloride, divinylbenzene, organic acids, and organic acid anhydrides.

[0140] It is advantageous to use certain types of crosslinking agents to achieve effective crosslinking and ensure desired physical properties.

[0141] In one example, the cross-linking agent may be an organic acid having two or more carboxyl groups, an anhydride of the organic acid, or an organic compound having two or more formyl groups or aldehyde groups.

[0142] The organic acid, anhydride of the organic acid, or organic compound may be composed of only carbon, oxygen, and hydrogen.

[0143] The type of organic acid that can be used as the crosslinking agent is not particularly limited, but an organic acid having a molecular weight of about 90 g / mol to 300 g / mol or about 100 g / mol to 250 g / mol may be used. The organic acid may have 2 to 10, 2 to 9, 2 to 8, 2 to 7, 2 to 6, 2 to 5, 2 to 4, or 2 to 3 carboxyl groups, or may have 2 or 3 carboxyl groups.

[0144] Such organic acids include, but are not limited to, citric acid, succinic acid, pimelic acid, and adipic acid.

[0145] The organic acids or anhydrides thereof may be used as the cross-linking agents.

[0146] The type of organic compound having two or more aldehyde groups that can be used as the crosslinking agent is not particularly limited, but an organic compound having a molar mass of about 90 g / mol to 200 g / mol or about 90 g / mol to 150 g / mol may be used. The organic compound may have 2 to 10, 2 to 9, 2 to 8, 2 to 7, 2 to 6, 2 to 5, 2 to 4, or 2 to 3 aldehyde groups, or may have 2 or 3 aldehyde groups.

[0147] Such organic compounds include, but are not limited to, glutaraldehyde.

[0148] In one example, the cross-linking agent may be an oxidized polysaccharide (including an oxidized disaccharide). The definition of polysaccharide is as described above. When a polysaccharide component is oxidized, the hydroxyl groups contained in the polysaccharide are first converted to carbonyl groups to form the aldehyde groups, and further oxidation may produce carboxyl groups. The aldehyde groups and carboxyl groups can participate in a cross-linking reaction and may therefore be used as the cross-linking agent. Methods for oxidizing polysaccharides are well known.

[0149] Applicable oxidized polysaccharides include, but are not limited to, oxidized starch, oxidized dextrin, oxidized chitosan, oxidized chitin, oxidized sucrose, and / or oxidized maltose.

[0150] The oxidized polysaccharide may be, for example, a component having 2 to 10, 2 to 9, 2 to 8, 2 to 7, 2 to 6, 2 to 5, 2 to 4, or 2 to 3 aldehyde groups (formyl groups or aldehyde groups) and / or carboxyl groups, or 2 or 3 groups, and having a molar mass within a predetermined range.

[0151] In another example, the lower limit of the ratio of aldehyde groups and / or carboxyl groups per mole of the oxidized polysaccharide may be about 0.01 mol, 0.05 mol, 0.1 mol, 0.15 mol, 0.2 mol, 0.25 mol, or 0.3 mol, and the upper limit may be about 0.9 mol, 0.85 mol, 0.8 mol, 0.75 mol, 0.7 mol, 0.65 mol, 0.6 mol, 0.55 mol, 0.5 mol, 0.45 mol, 0.4 mol, 0.35 mol, or 0.3 mol. The molar ratio of aldehyde groups and / or carboxyl groups per mole of the oxidized polysaccharide may be equal to or greater than any of the above-mentioned lower limits, or equal to or less than any of the above-mentioned upper limits, or may be equal to or greater than any of the above-mentioned lower limits but equal to or less than any of the above-mentioned upper limits. The ratio is based on the oxidized polysaccharide. 1 This can be confirmed through H NMR analysis. 1 The carboxyl groups and / or aldehyde groups present in the polysaccharide can be quantified through H NMR analysis, and the ratio can be confirmed. 1 Methods for quantifying functional groups through 1 H NMR analysis are well known.

[0152] The lower limit of the molar mass of the oxidized polysaccharide may be about 100 g / mol, 150 g / mol, 200 g / mol, 250 g / mol, or 300 g / mol, and the upper limit may be about 1000 g / mol, 950 g / mol, 900 g / mol, 850 g / mol, 800 g / mol, 750 g / mol, 700 g / mol, 650 g / mol, 600 g / mol, 550 g / mol, 500 g / mol, 450 g / mol, 400 g / mol, or 350 g / mol. The molar mass may be equal to or greater than any of the lower limits, equal to or less than any of the upper limits, or equal to or greater than any of the lower limits but equal to or less than any of the upper limits. Among polysaccharides, disaccharides typically exhibit molar masses within the above ranges.

[0153] The polymeric material treated with such a crosslinking agent exhibits adequate gel strength and can satisfy the desired absorption characteristics and biodegradability.

[0154] The weight ratio of the crosslinking agent in the polymeric material relative to 100 parts by weight of the self-crosslinked polysaccharide component may be, at least, about 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 parts by weight, and at most, about 20, 18, 16, 14, 12, 10, 8, or 6 parts by weight. The ratio may be greater than or equal to any of the lower limits, less than or equal to any of the upper limits, or greater than or equal to any of the lower limits but less than or equal to any of the upper limits. Typically, the disaccharides of the polysaccharides have a molar mass within the ranges specified above.

[0155] At such a ratio, the polymer material exhibits adequate gel strength and can satisfy the desired absorption characteristics and biodegradability.

[0156] The polymeric material comprises a polysaccharide component as described above (a polysaccharide component that is self-crosslinked and bound to the crosslinker), and may further comprise other components as needed.

[0157] In one example, the percentage of the polysaccharide component (self-crosslinked and bound to the crosslinker) in the polymeric material may be as low as 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 92%, 94%, 96%, or 98% by weight, and as high as 100%, 98%, 96%, 94%, 92%, or 90% by weight. The percentage may be less than or equal to any of the aforementioned upper limits, or may be greater than or equal to or exceeding any of the aforementioned lower limits while still being less than or equal to any of the aforementioned upper limits.

[0158] Although there is no particular limitation on the proportion of the polysaccharide component in the polymer material, the higher the proportion, the greater the biodegradability of the polymer material. However, in the case of conventional absorbent materials using polysaccharide components, if the proportion of the polysaccharide component is increased too much in consideration of biodegradability, there is a problem that the absorption capacity decreases. However, in the present invention, the proportion of the polysaccharide component can be maintained at a high level, and the desired absorption capacity can be stably achieved.

[0159] The polymeric materials exhibit excellent absorbability and biodegradability at the same time and may be used in a variety of applications.

[0160] For example, the polymeric material may be used as an absorbent material for hygiene products such as diapers and sanitary napkins, or other applications requiring absorption. If necessary, the polymeric material may be subjected to additional crosslinking, surface treatment, or physical grinding steps to enhance its efficiency for use as the hygiene product or absorbent material.

[0161] The present invention therefore relates to absorbent materials or sanitary articles (such as diapers and sanitary napkins) comprising said polymeric materials.

[0162] There are no particular limitations on the specific manner in which the polymer material is applied to form the absorbent material or sanitary product, and for example, the same manner in which a conventional SAP is applied to form the absorbent material or sanitary product may be used. [Effects of the Invention]

[0163] The present invention can provide a polymer material having excellent biodegradability and absorbability, and uses thereof. [Brief explanation of the drawings]

[0164] [Figure 1] FIG. 1 shows the 1H NMR spectrum of the substance obtained in the preparation example. [Figure 2] FIG. 2 is a 1H NMR spectrum of the substance obtained in the preparation example. [Figure 3] FIG. 3 is a 1H NMR spectrum of the substance obtained in the preparation example. DETAILED DESCRIPTION OF THE INVENTION

[0165] The present invention will be described in detail below through examples and comparative examples, but the scope of the present invention is not limited to the following examples.

[0166] 1. Evaluation of Centrifuge Retention Capacity (CRC) Centrifugal water retention capacity (CRC) was measured in accordance with EDANA (European Disposables and Nonwovens Association) WSP 241.3. Approximately 0.2 g (W0) of the obtained polymer material was placed in a nonwoven bag, sealed, and then immersed in saline. The saline solution used was a 0.9 wt% NaCl aqueous solution. This condition was maintained for approximately 30 minutes, and the bag was then centrifuged at 250 G for 3 minutes to remove water, after which the mass of the bag (g, W2) was measured.

[0167] The same procedure was carried out on the same nonwoven bag that did not contain the polymer material, and the mass (g, W1) was measured.

[0168] The measurement results were substituted into the following formula A to calculate CRC (g / g).

[0169] The evaluation was carried out under constant temperature and humidity conditions (23±1° C., relative humidity: 50±10%).

[0170] [Formula A] CRC(g / g)={[W2(g)-W1(g)] / W0(g)}-1

[0171] 2.Absorbency under Pressure (AUP) evaluation The absorbency under load (AUP, 0.7 psi) of polymeric materials was measured according to the EDANA (European Disposables and Nonwovens Association) WSP 242.3 standard. A 400-mesh stainless steel wire mesh was attached to the bottom of a plastic cylinder with an inner diameter of approximately 60 mm. Approximately 0.90 g (W0) of polymeric material was evenly spread on the wire mesh at a temperature of 23±2°C and a relative humidity of 50%, and a piston capable of uniformly applying a load of approximately 0.7 psi was attached on top of the mesh to prepare a measuring device. The piston had an outer diameter slightly smaller than 60 mm and was positioned so that it could move up and down without forming a gap with the inner wall of the cylinder. The weight (unit: g) of the measuring device (W3) was then measured.

[0172] A glass filter approximately 90 mm in diameter and 5 mm thick was placed inside a petroleum dish approximately 150 mm in diameter, and physiological saline (0.9 wt% NaCl aqueous solution) was applied so that it was flush with the top surface of the glass filter. A piece of filter paper approximately 90 mm in diameter was placed on top of it. The measuring device was placed on the filter paper, and the physiological saline was allowed to absorb for 1 hour under a load of 0.7 psi. After 1 hour, the measuring device was lifted and its weight W4 (g) was measured.

[0173] The measured weights were substituted into the following formula B to calculate the absorbency under load (AUP) (g / g).

[0174] [Formula B] AUP(g / g) = [W4(g) - W3(g)] / W0(g)

[0175] 3. Measurement of biodegradability Biodegradation was measured according to the method specified in ISO 14855-1 (2005). This standard is a method for measuring the aerobic biodegradation of plastic materials under composting conditions, and calculates the biodegradation of polymer materials by quantifying the amount of carbon dioxide released by microbial metabolism of the material. The polymer materials were subjected to composting conditions according to the standard and the biodegradation was measured for six months, and the biodegradation was calculated as the ratio of the theoretical amount of carbon dioxide generated to the actual amount of carbon dioxide generated. The theoretical amount of carbon dioxide generated and the biodegradation degree were calculated using the following formulas C and D, respectively.

[0176] [Formula C] Theoretical carbon dioxide generation (ThCO2, g / container) = M T O T ×C T O T ×(44 / 12)

[0177] In equation C, MTOT is the amount (g) of total dry solids of the test material (polymer material) added to the compost at the start of the measurement, and C T O Tmeans the percentage of organic carbon (g / g) contained in the total dry solids of the test material.

[0178] [Formula D] Biodegradation (%)=[{(CO2) T -(CO2) B} / ThCO2]×100

[0179] In formula D, (CO2) T is the cumulative amount of carbon dioxide generated from the composting container contained in the test material (g / container), and (CO2) B is the average cumulative amount of carbon dioxide evolved from the inoculum container (g / container), and ThCO2 is the theoretical amount of carbon dioxide evolved as determined from Equation C above.

[0180] 4. Molecular weight measurement of polysaccharide components The molecular weight (weight average molecular weight, unit: g / mol) of the polysaccharide component was evaluated by the following method.

[0181] (1) Preparation of mobile phase Mobile phase A was prepared by filtering 1000 mL of 150 mM NaNO3 aqueous solution containing 0.02 wt% NaN3 through a solvent clarification system (Millipore Millisolve Kit, MilliporeSigma).

[0182] (2) Preparation of sample solution 25 mg of the sample to be measured for molecular weight was taken and mixed with 5 mL of 150 mM NaNO3 aqueous solution containing 0.02 wt% NaN3, heated at 80°C for 20 hours, and then filtered through a 0.4 μm nylon syringe filter to prepare a sample solution.

[0183] (3) GPC (Gel Permeation Chromatography) / MALS (Multi-Anglue Light Scattering Detection) conditions Using the sample solution and mobile phase A, the molecular weight was evaluated by the following method.

[0184] Measuring instrument: Agilent GPC (Agilent 1200 series, US) Stationary phase: Shodex OH-Pak 804 column and Shodex OH-Pak 80 column connected Mobile phase A: 0.02% NaN3, 150mM NaNO3 aqueous solution = 100 (v / v%) Flow rate: 0.4mL / min Stationary phase temperature: 25℃ Injection volume: 100μl (0.45μm filtered) Analysis time: 120 minutes

[0185] Production example 1. A polysaccharide (modified chitosan) (compound A) containing a modified monosaccharide unit of the following formula A was produced by the following method. The modified monosaccharide unit of the following formula A is a monosaccharide unit into which a maleic acid group has been introduced.

[0186] [ka]

[0187] 15 g of chitosan and 300 mL of DMSO (dimethyl sulfoxide) were placed in a 500 mL RBF (Round Bottom Flask) and gelatinized by stirring at 65°C for 30 minutes. Approximately 30 g of maleic anhydride was added to the gelatinized chitosan and reacted at 65°C for 3 hours. After the reaction was complete, the temperature was lowered to room temperature (approximately 25°C) and acetone was added to produce a precipitate. The precipitate was collected and dried in a vacuum drying oven at 40°C for one day to obtain the target product (Compound A) in a solid phase.

[0188] The degree of substitution of the target product (compound A) obtained is 1 It can be determined through H NMR analysis. 1 H NMR analysis included a Varian Unity Inova (500 MHz) spectrometer with a triple-resonance 5 mm probe. 1This is carried out at room temperature (approximately 25°C) using a H NMR spectrometer. 1 For 1 H NMR analysis, a Bruker Avance Neo instrument was used.

[0189] 50 mg of the target substance (compound A) in the solid phase obtained above was mixed with 200 mg of a 30% DCl in DO solution, and the mixture was stirred at 50°C for about 1 hour to induce a hydrolysis reaction. 1 H NMR analysis may be performed.

[0190] 1 The degree of substitution of the maleic acid group on the chitosan was confirmed by H NMR analysis. 1 1H NMR spectrum. Referring to Figure 1, peaks were observed at 6.3 ppm and 5.8 ppm, corresponding to the vinyl groups of the maleic acid groups, confirming that maleic acid groups had been introduced into the chitosan. The degree of substitution of maleic acid groups (-OCOCH=CHCOOH) in the maleated chitosan was determined based on the integral ratio of the peaks. The degree of substitution determined by this method was approximately 0.94.

[0191] Production example 2. A polysaccharide (modified starch) (compound B) containing a modified monosaccharide unit of the following formula B was prepared by the following method. The modified monosaccharide unit of the following formula B is a monosaccharide unit into which a maleic acid group has been introduced.

[0192] [ka]

[0193] 15 g of starch and 50 mL of DMSO (dimethyl sulfoxide) were placed in a 500 mL RBF (Round Bottom Flask) and gelatinized by stirring at 65°C for 2 hours. Potato starch was used as the starch. Approximately 30 g of maleic anhydride was added to the gelatinized starch and reacted at 65°C for 3 hours. After the reaction was completed, the temperature was lowered to room temperature, and acetone was added to produce a precipitate. The precipitate was collected and dried in a vacuum drying oven at 40°C for 1 day to obtain the target product (compound B) in a solid phase.

[0194] 50 mg of the target substance (compound B) in the solid phase obtained above was mixed with 200 mg of a 30% DCl in DO solution, and the mixture was stirred at 50°C for about 1 hour to induce a hydrolysis reaction. 1 H NMR analysis may be performed.

[0195] The degree of substitution of the target compound (compound B) was the same as in Production Example 1. 1 The degree of substitution was confirmed by H NMR analysis, and it was found to be about 0.8. 1 1 H NMR analysis results.

[0196] Production example 3. Oxidized polysaccharides (oxidized disaccharides) (oxidized maltose) were prepared as follows. 20 g of maltose was dissolved in 100 mL of distilled water in a 500 mL RBF (Round Bottom Flask). Covered with foil to protect from light, approximately 0.5 to 0.75 equivalents of NaIO4 was added and stirred at room temperature (approximately 25°C) for approximately 24 hours. Barium acetate was then added and stirred, and the filtered solution was dried to obtain oxidized polysaccharides (oxidized maltose). Figure 3 shows the structure of the target product (oxidized maltose). 1 The results of H NMR analysis show that the degree of aldehyde group formation in oxidized maltose is 1 This can be confirmed by examining the 1 H NMR analysis. 1The integration value of the peak observed in the 8.0-8.5 ppm range in the H NMR analysis (the peak corresponding to the aldehyde group) is set to 1, and the integration values ​​of other peaks are set based on this. The integration value of the peak observed in the 3.0-4.0 ppm range is then divided by 14 to determine the value. The peak observed in the 3.0-4.0 ppm range is a peak derived from the ring structure of oxidized maltose, and the value 14 is therefore a value related to the number of hydrogen atoms present in the ring structure, divided by 14. Therefore, the integration value of the peak observed in the 8.0-8.5 ppm range (the peak corresponding to the aldehyde group) and the integration value of the peak observed in the 3.0-4.0 ppm range are divided by 14 and compared to determine the proportion of aldehyde groups in oxidized maltose. As a result of confirming this method, the oxidized maltose contains about 0.3 moles of aldehyde groups per mole.

[0197] Example 1 Carboxymethyl cellulose (CMC) was self-crosslinked to prepare a self-crosslinked polysaccharide component. The CMC used was a carboxymethyl cellulose (CMC) that, when prepared into a 1 wt% aqueous solution, had a viscosity of about 1600 cP to 1700 cP and a degree of substitution (DS) of about 0.7 to 0.8. The viscosity of the aqueous solution was measured using a Brookfield viscometer-DV2T instrument, using a V-74 spindle, a speed of 50 rpm, and a measurement temperature of 25°C. The degree of substitution (DS) refers to the degree of substitution of carboxyl groups present in the CMC, and was measured in accordance with Preparation Examples 1 and 2. 1The results were obtained through H NMR analysis. 20 g of the CMC was dissolved in 800 mL of distilled water, spread thinly on a tray, and then dried in an oven at approximately 40°C. The mixture of CMC and distilled water was adjusted to approximately pH 10.5 by adding approximately 1N NaOH aqueous solution. After drying, the CMC was heated at 120°C for 3 hours to produce a self-crosslinked polysaccharide component, which was then crushed and classified to obtain a material with a particle size of approximately 300 μm to 600 μm.

[0198] The resulting material was subjected to surface cross-linking. Surface cross-linking was carried out using a surface cross-linking solution prepared by dissolving 0.18 g of the compound (oxidized maltose) from Preparation Example 3 together with 0.018 g of AlCl3 in a solution of 0.6 g of acetone and 0.6 g of water. 3.6 g of the material ground and classified to a particle size of approximately 300 μm to 600 μm was placed on an aluminum dish, and the cross-linking solution was uniformly sprayed onto it. After mixing until the cross-linking agent was thoroughly mixed, the mixture was heated at 120°C for 30 minutes to obtain a polymer material containing a self-cross-linked polysaccharide component and a cross-linking agent bonded to the component. The resulting material was further ground and classified as necessary.

[0199] Example 2. A polymer material was produced in the same manner as in Example 1, except that the CMC used had a viscosity of about 9000 cP to 10000 cP in an aqueous solution containing 1 wt % of the CMC and a degree of substitution (DS) of 0.65 to 0.75. The viscosity and degree of substitution were measured in the same manner as in Example 1.

[0200] Example 3. A polymer material was produced in the same manner as in Example 1, except that the target product of Production Example 1 (compound A) was used instead of CMC.

[0201] Example 4. A polymer material was produced in the same manner as in Example 1, except that the target product of Production Example 2 (compound B) was used instead of CMC.

[0202] Comparative Example 1 The polymer material was prepared in the same manner as in Example 4, but without the surface cross-linking step after the self-cross-linking step.

[0203] The physical properties of the polymer material were measured and the results are shown in Table 1 below.

[0204] [Table 1]

Claims

1. a self-crosslinked polysaccharide component; a cross-linking agent associated with said self-cross-linked polysaccharide component.

2. 10. The polymeric material of claim 1, wherein the self-crosslinked polysaccharide component is in particulate form and the crosslinking agent is attached to the surface of the particulate form.

3. 2. The polymeric material of claim 1, having a centrifugal water retention capacity of at least 10 g / g according to EDANA (European Disposables and Nonwovens Association) method WSP 241.

3.

4. 2. The polymeric material of claim 1, having an absorbency at 0.7 psi according to EDANA (European Disposables and Nonwovens Association) method WSP 242.3 of at least 3 g / g.

5. The polymer material according to claim 1, which has a biodegradability of 50% or more.

6. 10. The polymeric material of claim 1, wherein the self-crosslinking of the polysaccharide component is carried out using an acidic polysaccharide having a degree of substitution in the range of 0.4 to 2.

5.

7. 2. The polymer material of claim 1, wherein the self-crosslinked polysaccharide component comprises a polymer chain comprising monosaccharide units linked by glycosidic bonds and a bond of the formula 1 below connecting the polymer chains. 【Chemistry 1】 In Chemical Formula 1, X １ is an oxygen atom or NR １１ and R １１ is a hydrogen atom, an alkyl group, or an alkylcarbonyl group, and L １ is an alkylene group, an alkylidene group, or a bond represented by the following formula 2, and L ２ is a single bond or -(CH ２ )-O-. 【Chemistry 2】

8. 8. The polymeric material of claim 7, wherein the monosaccharide unit has a ring structure containing carbon and oxygen atoms as ring atoms, and the bond of formula (I) is connected to the carbon atom of the ring structure directly or via a methylene group.

9. The polymer material according to claim 1 , wherein the polysaccharide component comprises a unit represented by the following formula: 【Transformation 3】 In Chemical Formula 3, R １ represents a hydroxy group, an amino group, -L ５ -C(=O)-OH, -L ５ -C(=O)-O － or a functional group of the following formula 4, R ３ represents a hydroxy group, -L ５ -C(=O)-OH, -L ５ -C(=O)-O － or a functional group of the following formula 4, ３ and L ４ is a single bond, and the other is CHR ２ and R ２ represents a hydroxy group, -L ５ -C(=O)-OH, -L ５ -C(=O)-O － or a functional group of the following formula 4, ５ is an alkylene group or an alkylidene group, １ ~R ３ is an oxygen atom in the bond of the formula (1) (excluding the oxygen atom present in the carbonyl group). 【Chemistry 4】 In Chemical Formula 4, X ２ is an oxygen atom or NR １１ and R １１ is a hydrogen atom, an alkyl group, or an alkylcarbonyl group, and M １ is hydrogen or a metal, and the M １ When is a metal, the O-M １ The bond is an ionic bond.

10. 2. The polymer material according to claim 1, wherein the crosslinking agent is at least one selected from the group consisting of a polyfunctional epoxy compound, an epoxy silane compound, an amino silane compound, epichlorohydrin, formaldehyde, glutaraldehyde, sucrose oxide, acyl chloride, carbonate, diamine, diol, carbon disulfide, phosphoryl chloride, divinylbenzene, organic acid, and organic acid anhydride.

11. The polymeric material of claim 1 , wherein the crosslinking agent is an organic acid having at least two carboxyl groups, an anhydride of the organic acid, or an organic compound having at least two aldehyde groups.

12. The polymeric material of claim 1 , wherein the cross-linking agent is an oxidized polysaccharide.

13. 2. The polymer material of claim 1, wherein the cross-linking agent is at least one selected from the group consisting of oxidized starch, oxidized dextrin, oxidized chitosan, oxidized chitin, oxidized sucrose, and oxidized maltose.

14. 13. The polymeric material of claim 12, wherein the oxidized polysaccharide contains aldehyde groups in the range of 0.01 moles to 0.9 moles per mole.

15. 13. The polymeric material of claim 12, wherein the molar mass of the oxidized polysaccharide is in the range of 100 g / mol to 1000 g / mol.

16. 10. The polymeric material of claim 1, comprising 0.01 to 20 parts by weight of a cross-linking agent per 100 parts by weight of the self-cross-linked polysaccharide component.

17. An absorbent material comprising a polymeric material according to any one of claims 1 to 16.

18. A hygiene article comprising the polymeric material according to any one of claims 1 to 16.

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