polymer materials

Abstract

The present invention can provide a polymer material, a method for producing the same, and uses thereof. The present invention can provide a polymer material produced from a biodegradable material and exhibiting balanced absorption properties. The present invention can further provide a method for producing the polymer material and uses thereof.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0008025, 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.

[0009] Absorbency is typically evaluated using CRC (Centrifugal Retention Capacity), AUP (Absorbency Under Pressure), and Vortex tests. The CRC test evaluates the water retention capacity of a polymer material without applying pressure, while the AUP test evaluates the absorption properties of a polymer material with a certain level of pressure applied. However, even in materials with excellent CRC properties, the application of pressure can cause a decrease in absorption properties, resulting in failure to maintain AUP properties.

[0010] Therefore, in order to improve the AUP characteristics of absorbent materials, a cross-linking agent is often introduced to the surface of the absorbent material to strengthen the gel strength, but this leads to a problem that the absorption time is shortened, resulting in a deterioration in the Vortex test evaluation results. Therefore, it is difficult to obtain a material that ensures a good balance of CRC, AUP, and Vortex test results, which correspond to the absorption characteristics. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention relates to a polymer material, a method for producing the same, and uses thereof. An object of the present invention is to provide a polymer material made of a biodegradable material and exhibiting balanced absorption properties. Another object of the present invention is to provide a method for producing the polymer material and uses thereof. [Means for solving the problem]

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] In the present invention, the term "hydrogel polymer material" refers to a water-absorbing material comprising cross-linked polymers, which may also be referred to herein simply as a hydrogel.

[0020] The polymer material of the present invention may be a hydrogel, which has balanced absorption properties, particularly suitable levels of centrifuge retention capacity (CRC) and absorbency under load (AUP), as well as a fast absorption time.

[0021] For example, the polymer material may have a vortex absorption time within a predetermined range for a 0.9 wt% NaCl aqueous solution. The vortex absorption time refers to the rate at which the polymer material absorbs a 0.9 wt% NaCl aqueous solution, measured according to the method described in the Examples section of this specification. The upper limit of the vortex absorption time of the polymer material may be approximately 150 seconds, 140 seconds, 130 seconds, 120 seconds, 110 seconds, 100 seconds, 90 seconds, 80 seconds, 70 seconds, or 65 seconds. Since a shorter absorption time indicates a faster absorption rate, the lower limit is not particularly limited. For example, the lower limit of the absorption time may be approximately 0 seconds, 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, or 65 seconds. The absorption time 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 still be less than or equal to any of the above upper limits.

[0022] The polymeric material may have a centrifuge retention capacity (CRC) according to EDANA (European Disposables and Nonwovens Association) method WSP 241.3 of 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 at its lower limit, and may have an upper limit of about 60 g / g, 55 g / g, 50 g / g, 45 g / g, 40 g / g, or 35 g / g. The CRC may be equal to or greater than any of the lower limits, or may be equal to or greater than any of the lower limits but less than or equal to any of the upper limits.

[0023] For example, the polymeric material may have a lower limit of absorbent capacity under pressure (AUP) at 0.7 psi according to EDANA (European Disposables and Nonwovens Association) method WSP 242.3 of 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, 10.5 g / g, 11 g / g, or 11.5 g / g, and an upper limit of 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 equal to or greater than any of the lower limits mentioned above, or may be equal to or greater than any of the lower limits mentioned above but less than or equal to any of the upper limits mentioned above.

[0024] The polymer material can exhibit at least one of the properties of centrifugal water retention capacity and absorbency under pressure while exhibiting the Vortex absorption time, or can exhibit the properties of centrifugal water retention capacity and absorbency under pressure while exhibiting the Vortex absorption time.

[0025] The polymer material of the present invention is produced using a biodegradable material as a main component, and can exhibit excellent biodegradability.

[0026] For example, the lower limit of the biodegradability of the polymer material may be about 50%, 52%, 54%, 56%, 58%, 60%, 62%, 64%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96%, 98%, or 99%, and the upper limit may be 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 may be greater than or exceeding any of the lower limits but less than or equal to any of the upper limits. The biodegradability may be measured according to the method described in the Examples of this specification.

[0027] The present invention relates to polymeric materials.

[0028] The term "polymer material" refers to a material containing a polymer. The polymer refers to a substance formed by two or more units linked by a covalent bond. In one example, the polymer refers 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 limit to 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.

[0029] The weight average molecular weight is a value measured by the method described in the examples of this specification.

[0030] In one example, the lower limit of the polymer content in the polymer material may be about 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% by weight, and the upper limit may be about 100%, 98%, 96%, 94%, 92%, or 90% by weight. The percentage may be equal to or greater than any of the lower limits, or may be equal to or greater than any of the lower limits but less than or equal to any of the upper limits.

[0031] The polymeric materials of the present invention may also include a polysaccharide component.

[0032] 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.

[0033] 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.

[0034] 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 construed 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 of the present invention are not limited to these.

[0035] When the polymeric material (e.g., the polysaccharide or polysaccharide component) is crosslinked and has absorbent properties, the polymeric material is referred to herein as a hydrogel polymeric material or hydrogel. In one example, the polymeric material may be in the form of a powder formed by a milling process or the like.

[0036] 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.

[0037] As used herein, the polymeric material may comprise at least a self-crosslinked polysaccharide component of the above types of crosslinked polysaccharides.

[0038] 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 proportion 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 proportion 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.

[0039] 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.

[0040] 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, in general, 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 balanced absorption capacity.

[0041] In the present invention, the self-crosslinking of the polysaccharide may be carried out using so-called acidic polysaccharides, which, as is well known, are polysaccharides having acidic groups, such as carboxylic groups, phosphate groups, phosphite groups, and / or sulfuric ester groups, or salts thereof.

[0042] 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.

[0043] For example, the lower limit of the degree of substitution may be about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 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 exceeding any one of the lower limits, or may be equal to or exceeding any one of the upper limits, or may be equal to or exceeding any one of the lower limits but equal to or less than any one of the upper limits. Within this range of substitution degree, crosslinking of the polysaccharide may be carried out effectively, and the physical properties of the resulting polymer material (e.g., absorbency and / or biodegradability) may be stably ensured. A high degree of substitution is advantageous in terms of absorption properties because the polysaccharide or polysaccharide component contains a large number of 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 absorption properties after crosslinking. Therefore, an appropriate degree of substitution may be selected taking these factors into consideration.

[0044] 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. 1This 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.

[0045] 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.

[0046] The type of polysaccharide having a carboxyl group is not particularly limited. For example, a polysaccharide having a carboxyl group itself, such as carboxylmethyl cellulose (CMC), which is a wood-based polysaccharide, or a polysaccharide into which a carboxyl group has been introduced through a process such as maleation or carboxyalkylation may be used to perform the self-crosslinking.

[0047] 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.

[0048] In this case, the cross-linking bond may be linked to the monosaccharide unit.

[0049] The cross-linked bond may be a bond represented by the following formula 1.

[0050] [ka]

[0051] 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-.

[0052] [ka]

[0053] X1, shown on the leftmost side in Formula 1, may be directly linked to a monosaccharide unit of the polymer chain.

[0054] In the formula 1, when X1 is an oxygen atom, starch or the like is used as the crosslinker, and NR 11 In this case, chitosan or chitin is used as a polysaccharide for the crosslinking.

[0055] 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.

[0056] 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.

[0057] When L1 in Chemical Formula 1 is Chemical Formula 2, the carbon atom 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 in Chemical Formula 2 is linked to the carbon atom of the carbonyl group on the right side of L1 in Chemical Formula 1.

[0058] There may be at least one bond of formula (1) in the self-crosslinked polysaccharide component.

[0059] 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.

[0060] 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.

[0061] 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-).

[0062] At least one or all of the leftmost oxygen atom and the rightmost oxygen atom of 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 of the ring structure or may be connected via a methylene group (-CH2-).

[0063] In the above, being linked via a methylene group (-CH2-) means that only the methylene group (-CH2-) is present between the leftmost oxygen atom of the formula 1 or the rightmost oxygen atom of the formula 1 (when L2 is not a single bond, the oxygen atom of -(CH2)-O-) and the carbon atom of the ring structure.

[0064] In this case, more specifically, the polysaccharide component may contain a unit represented by the following formula 3.

[0065] [ka]

[0066] 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).

[0067] [ka]

[0068] 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.

[0069] -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.

[0070] Such functional groups are introduced to participate in the above-mentioned self-crosslinking reaction to form crosslinked bonds, but not all of the introduced functional groups may participate in the crosslinking reaction, and in that case, some functional groups may remain.

[0071] 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.

[0072] 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.

[0073] 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-).

[0074] 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.

[0075] As described above, the self-crosslinking structure can be realized by esterifying acidic polysaccharides, particularly polysaccharides having carboxyl groups. In the present invention, by adjusting the reaction conditions, particularly the pH, in the self-crosslinking reaction, a polymer material with well-balanced absorption properties can be provided.

[0076] 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.

[0077] 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 polymer units 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] Acidic groups (such as carboxyl groups) may be introduced into the polysaccharide by reacting the polysaccharide with the treating agent under appropriate conditions.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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 the use of such solvents may not result in the desired reaction.

[0090] 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.

[0091] The ratio of hydroxide to treating agent within the mixture may also be controlled.

[0092] 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.

[0093] 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, stably maintaining reaction efficiency and workability, and suppressing unwanted side reactions.

[0094] The ratio (A / B) 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 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] Carboxyalkylation is carried out through the above process to obtain the desired polysaccharide.

[0101] 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 polysaccharide may be recovered and then the self-crosslinking step may be carried out.

[0102] 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.

[0103] The polymer material may further include a crosslinking agent bonded to the self-crosslinked polysaccharide component along with the self-crosslinked polysaccharide component. This treatment may be introduced by reacting the self-crosslinked polysaccharide component with the crosslinking agent. That is, the polymer material of the present invention can be provided in a state in which two or more polysaccharide molecules are crosslinked by the self-crosslinking described above and then additionally crosslinked by applying the crosslinking agent. This additional crosslinking is introduced to improve the gel strength of the self-crosslinked polysaccharide component and improve the absorbency under load (AUP) and / or saline flow conductivity. Typically, applying a crosslinking agent for this purpose improves the absorbency under load of the polymer material, but at the expense of a reduced absorption rate. However, the present invention can provide a material that exhibits balanced absorbency even after applying the crosslinking agent by controlling the crosslinking conditions during the self-crosslinking step.

[0104] The additional crosslinking agent may be introduced by, for example, subjecting the self-crosslinked polysaccharide component to a process such as grinding to powderize it, and then reacting the crosslinking agent with the surface of the powder. In this case, the polymer material may contain the self-crosslinked polysaccharide component in particulate form and the crosslinking agent bound to the surface of the particles. In such cases, the particle size is not particularly limited and may be controlled to an appropriate size depending on the application. Typically, the particle size may be within the range of approximately 100 μm to 1,000 μm.

[0105] The crosslinking agent may be a substance having two or more functional groups capable of reacting with the functional groups (e.g., hydroxyl, amino, 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 the functional groups (e.g., hydroxyl, amino, or carboxyl groups) of the polysaccharide component, or may have 2 or 3 functional groups.

[0106] Applicable types of crosslinking agents include at least one selected from the group consisting of multifunctional epoxy compounds, epoxy silane compounds, amino silane compounds, epichlorohydrin, acyl chloride, carbonate, diamine, diol, carbon disulfide, phosphoryl chloride, divinylbenzene, organic acids, and organic acid anhydrides.

[0107] It is advantageous to use certain types of crosslinking agents to achieve effective crosslinking and ensure desired physical properties.

[0108] 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 a carbonate-based compound.

[0109] The organic acid, anhydride of the organic acid, or organic compound may be composed of only carbon, oxygen, and hydrogen.

[0110] 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.

[0111] Such organic acids include, but are not limited to, citric acid, succinic acid, pimelic acid, and adipic acid.

[0112] The organic acids or anhydrides thereof may be used as the cross-linking agents.

[0113] As the carbonate-based compound that can be used as the crosslinking agent, for example, alkylene carbonate may be used, and for example, alkylene carbonates in which the alkylene group has 1 to 20, 1 to 16, 1 to 12, 1 to 8, 1 to 4, 2 to 20, 2 to 16, 2 to 12, 2 to 8, or 2 to 4 carbon atoms may be used.

[0114] The polymeric material treated with such a crosslinking agent exhibits adequate gel strength and can satisfy the desired absorption characteristics and biodegradability.

[0115] 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.

[0116] At such a ratio, the polymer material exhibits adequate gel strength and can satisfy the desired absorption characteristics and biodegradability.

[0117] 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.

[0118] 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.

[0119] 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.

[0120] The present invention relates to a method for producing such polymeric materials.

[0121] The method may include the steps of self-crosslinking a polysaccharide to prepare the self-crosslinked polysaccharide component, and reacting the prepared self-crosslinked polysaccharide component with the crosslinking agent.

[0122] The self-crosslinked polysaccharide component may be an acidic polysaccharide as described above (eg, an acidic polysaccharide having the degrees of substitution described above).

[0123] The self-crosslinking of the polysaccharide may be carried out at a pH adjusted to a predetermined range. For example, the lower limit of the pH at which the self-crosslinking is carried out may be about 9, 9.5, 10, or 10.5, and the upper limit may be about 11.35, 11, or 10.5. The pH 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, or may be greater than or equal to any of the lower limits but less than or equal to any of the upper limits.

[0124] Although it is unclear why the desired results are obtained through self-crosslinking in this pH range, it is believed that the pH affects the crosslinking rate of polysaccharides or the crosslinking density of the self-crosslinked polysaccharide components, and this effect is strengthened by the reaction with the crosslinking agent described below, ultimately resulting in the realization of a crosslinked structure that can exhibit balanced absorption capacity.

[0125] The method for performing the self-crosslinking is not particularly limited, but for efficient self-crosslinking, the polysaccharide may be dispersed in a solvent and then the pH may be maintained within the above range.

[0126] In this process, an aqueous solvent, such as water, may be used as the solvent. Specifically, tap water, distilled water, deionized water, or purified water may be used. It is appropriate to use substantially only the aqueous solvent (e.g., water) as the solvent during self-crosslinking. 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, being 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 ratio 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 mentioned above, but less than or equal to any of the upper limits mentioned above.

[0127] 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.

[0128] Self-crosslinking may be performed by dissolving the polysaccharide in the solvent and maintaining the pH at the aforementioned level. If necessary, an additional step, such as a stirring step, that can promote self-crosslinking may be performed. The method for maintaining the pH within the aforementioned range is not particularly limited. If the pH within the aforementioned range is achieved by adding the polysaccharide, self-crosslinking may be performed under that condition. If the desired pH is not achieved, the pH may be adjusted by adding an appropriate acid or base, taking the desired pH into consideration. In this case, the hydroxide used in the carboxyalkylation may be used as the base, and hydrochloric acid, sulfuric acid, or the like may be used as the acid, but these are not limited thereto.

[0129] A base may be applied to maintain the desired pH level. Examples of bases that can be applied in this process include NaOH, KOH, K2CO3, Na2CO3, and / or NaHCO3, but also various types of organic bases (e.g., amine-based or ammonia-based bases such as NH3, NH4OH, DIPEA (N,N-Diisopropylethylamine), TEA (triethylamine) etc.) and / or inorganic bases (Mg(OH)2, Ca(OH)2, Al(OH)3, Ca 10 Suitable types may be selected from (PO4)6(OH)2, Li2O, Na2O, K2O, CaO, etc.

[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 thickeners, plasticizers, storage stabilizers and / or antioxidants, 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] In one example, the process of obtaining the self-crosslinked polysaccharide component may be carried out at the temperature and for the time period described above while evaporating or volatilizing the solvent, thereby obtaining the desired self-crosslinked polysaccharide component.

[0136] The self-crosslinked polysaccharide component obtained as described above may be reacted with a crosslinking agent in a subsequent reaction.

[0137] After the self-crosslinking step, the polysaccharide component may be reacted with the crosslinking agent as it is, or may be reacted with the crosslinking agent after further treatment to increase crosslinking efficiency as needed. For example, after the self-crosslinking step, the polysaccharide component may be granulated and then reacted with the crosslinking agent. For example, the polysaccharide component may be granulated through an appropriate grinding and / or classification step, and the granulated polysaccharide component may be reacted with the crosslinking agent.

[0138] In this case, the process may include the steps of: granulating the self-crosslinked polysaccharide component; and reacting the surface of the granulated self-crosslinked polysaccharide component with the crosslinking agent.

[0139] The method for reacting the polysaccharide component with the crosslinker is not particularly limited. For example, a method of contacting the polysaccharide component with the crosslinker in an appropriate reaction medium such as a solvent and allowing the reaction to occur may be applied. When the particulate polysaccharide component reacts with the crosslinker, a method of spraying the crosslinker or a crosslinking liquid containing the crosslinker onto the surface of the particulate polysaccharide component to bring the crosslinker into contact with the surface and allow the reaction to proceed may also be used.

[0140] In this case, the above-mentioned crosslinking agents may be used as the crosslinking agent.

[0141] The reaction with the crosslinking agent may be carried out in the presence of additives such as a catalyst, a thickener, a plasticizer, a storage stabilizer and / or an antioxidant, if necessary.

[0142] 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.

[0143] 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.

[0144] After reaction with the crosslinking agent as described above, the desired polymer material can be obtained by further processing (for example, grinding / classifying) if necessary.

[0145] The polymeric materials are made from biodegradable materials, exhibit balanced absorption properties, and may be used in a variety of applications.

[0146] For example, the polymeric material may be used as an absorbent material for hygiene products such as diapers and sanitary napkins, or other absorbent applications, and may be subjected to further crosslinking, surface treatment, or physical grinding steps, if necessary, to enhance its efficiency for use as the hygiene product or absorbent material.

[0147] The present invention therefore relates to absorbent materials or sanitary articles (such as diapers or sanitary napkins) comprising said polymeric materials.

[0148] 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 manner in which a conventional SAP is applied to form the absorbent material or sanitary product may be similarly used. [Effects of the Invention]

[0149] The present invention can provide a polymer material, a method for producing the same, and uses thereof. The present invention can provide a polymer material produced from a biodegradable material and exhibiting balanced absorption properties. The present invention can further provide a method for producing the polymer material and uses thereof. DETAILED DESCRIPTION OF THE INVENTION

[0150] 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.

[0151] 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.

[0152] 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.

[0153] The measurement results were substituted into the following formula A to calculate CRC (g / g).

[0154] The evaluation was carried out under constant temperature and humidity conditions (23±1° C., relative humidity: 50±10%).

[0155] [Formula A] CRC(g / g)={[W2(g)-W1(g)] / W0(g)}-1

[0156] 2. Evaluation of Absorbency under Pressure (AUP) 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.

[0157] 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.

[0158] The measured weights were substituted into the following formula B to calculate the absorbency under load (AUP) (g / g).

[0159] [Formula B] AUP(g / g) = [W4(g) - W3(g)] / W0(g)

[0160] 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.

[0161] [Formula C] Theoretical carbon dioxide generation (ThCO2, g / container) = M T O T ×C T O T ×(44 / 12)

[0162] In formula C, M T O T 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.

[0163] [Formula D] Biodegradation (%)=[{(CO2) T -(CO2) B} / ThCO2]×100

[0164] In Equation D, (CO2)T is the cumulative amount of carbon dioxide generated from the composting containers contained in the test material (g / container), (CO2)B is the average cumulative amount of carbon dioxide generated from the inoculum containers (g / container), and ThCO2 is the theoretical amount of carbon dioxide generated determined from Equation C above.

[0165] 4. Evaluation of Vortex absorption time Approximately 50 mL of a 0.9 wt% NaCl aqueous solution (physiological saline) was added to a beaker, and a cylindrical stirring bar (diameter: approximately 6 mm, length: approximately 30 mm) was placed in the aqueous solution. While the stirring bar was rotating on a stirring plate at a rotation speed of approximately 600 rpm, approximately 0.1 g of the polymer material prepared in the Examples or Comparative Examples was added to the beaker. While maintaining this condition, a vortex of saline was observed on the surface of the polymer material while the polymer material was absorbing the saline. However, once absorption by the polymer material was complete, the vortex disappeared. The time from the time the polymer material was added to the time when the vortex was no longer observed was measured and defined as the absorption rate.

[0166] Example 1 A self-crosslinked polysaccharide component was prepared by self-crosslinking carboxymethyl cellulose (CMC), a wood-based polysaccharide. 20 g of CMC was dissolved in 800 mL of distilled water, spread thinly on a tray, and then dried in an oven at 40°C. Approximately 0.5 N NaOH aqueous solution was added to the mixture of CMC and distilled water to adjust the pH to approximately 10.5. After drying, the CMC was heated at 120°C for 3 hours to prepare a self-crosslinked polysaccharide component. The polysaccharide component was then crushed and classified to obtain a material with particle sizes of approximately 300 μm to 600 μm.

[0167] The resulting material was subjected to surface cross-linking. Surface cross-linking was carried out using a surface cross-linking solution prepared by dissolving 0.072 g of propylene carbonate in a solution of 0.627 g of acetone and 0.4 g of water together with 0.018 g of AlCl3. 3.6 g of the material, which had been crushed and classified to a particle size of approximately 300 μm to 600 μm, was placed on an aluminum dish, and the surface cross-linking solution was uniformly sprayed onto it. After mixing until the cross-linking agent was fully dissolved, 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 may be further crushed and classified as necessary.

[0168] Example 2. A polymer material was prepared in the same manner as in Example 1, except that succinic acid was used instead of propylene carbonate as the cross-linking agent. A surface cross-linking liquid was prepared by mixing 0.072 g of succinic acid, 1.26 g of acetone, and 0.4 g of water. The cross-linking was performed by spraying the cross-linking liquid evenly onto the surface of the self-cross-linked particulate polysaccharide component and maintaining the temperature at about 120°C for 1 hour.

[0169] Example 3 A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at 11.06 by adjusting the amount of NaOH added during self-crosslinking.

[0170] Comparative Example 1 A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at 11.37 by adjusting the amount of NaOH added during self-crosslinking.

[0171] Comparative Example 2 A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at level 7 by adjusting the amount of NaOH added during self-crosslinking.

[0172] Comparative Example 3. A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at level 9 by adjusting the amount of NaOH added during self-crosslinking.

[0173] Comparative Example 4. A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at a level of 6.56 by adding HCl during self-crosslinking.

[0174] Comparative Example 5. A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at a level of 4.41 by adding HCl during self-crosslinking.

[0175] Comparative Example 6. A polymer material was obtained in the same manner as in Example 2, except that the pH was controlled at a level of 5.24 by adding HCl during self-crosslinking.

[0176] The physical property measurement results for the polymer materials of the Examples and Comparative Examples are shown in Table 1. In the case of Comparative Examples 5 and 6, the centrifuge retention capacity (CRC) and absorbency under load (AUP), among the absorption properties, were so low that the vortex absorption time could not be measured.

[0177] [Table 1]

Claims

1. a self-crosslinked polysaccharide component and a crosslinking agent associated with the self-crosslinked polysaccharide component; A polymeric material having a Vortex absorption time of 150 seconds or less for a 0.9 wt % NaCl aqueous solution.

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

3. 2. The polymeric material of claim 1, having an Absorption Under Pressure (AUP) at 0.7 psi according to EDANA Method WSP242.3 of 10 g / g or greater.

4. 2. The polymer material according to claim 1, having a Centrifuge Retention Capacity (CRC) according to EDANA Method WSP241.3 of 20 g / g or more.

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

6. The polymeric material of claim 1, wherein the polysaccharide is an acidic polysaccharide having a degree of substitution in the range of 0.1 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 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, an acyl chloride, a carbonate, a diamine, a diol, a carbon disulfide, a phosphoryl chloride, divinylbenzene, an organic acid, and an organic acid anhydride.

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

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

13. 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.

14. cross-linking the polysaccharide under conditions of pH greater than 9 and less than or equal to 11.35 to prepare a self-cross-linked polysaccharide component; A method for producing a polymeric material comprising the step of reacting said self-crosslinked polysaccharide component with a crosslinking agent.

15. 15. A method for producing a polymeric material according to claim 14, comprising the steps of: particulating a self-crosslinked polysaccharide component; and reacting a crosslinking agent with the surface of the particulated self-crosslinked polysaccharide component.

16. An absorbent material comprising a polymeric material according to any one of claims 1 to 13.

17. A hygienic article comprising a polymeric material according to any one of claims 1 to 13.

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