polymer composition

Abstract

The present invention relates to a polymer composition and its uses. The present invention can provide a polymer composition having excellent biodegradability and water absorption capacity, and its uses. The present invention can provide the polymer composition and its uses by controlling the ratio of amylose and amylopectin in the polysaccharide component contained in the polymer composition and the molecular weight of the polysaccharide component.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0110608, filed on September 1, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a polymer composition and its uses. [Background technology]

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

[0004] Such polymers can 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 wide variety of applications, including hygiene products such as sanitary napkins and diapers, medical products, daily necessities, agricultural materials, gardening materials, transportation materials, civil engineering and construction materials, electrical and electronic equipment-related materials, and water treatment agents.

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

[0006] Although such materials are relatively inexpensive and have excellent water absorption capacity, they remain semi-permanently even after disposal, which can cause 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 balanced physical properties. For example, the most typical physical property required for SAPs is water absorption, but currently known SAPs made from biodegradable materials either do not sufficiently secure at least one of water absorption 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 composition that can ensure excellent water absorption capacity and biodegradability at the same time, and uses thereof. [Means for solving the problem]

[0010] Of the physical properties mentioned in this specification, values ​​of physical properties that are affected by the measurement temperature are the results measured at room temperature unless otherwise specified.

[0011] As used herein, the term "room temperature" refers to a natural temperature that is not artificially heated or cooled, and may refer to, 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] Of the physical properties mentioned in this specification, values ​​of physical properties that are affected by measurement pressure are the results of measurements at normal pressure unless otherwise specified.

[0013] As used herein, the term "normal pressure" refers to a pressure that is not artificially increased or decreased, and may refer to a pressure of approximately 740 mmHg to 780 mmHg, for example.

[0014] Of the physical properties mentioned in this specification, values ​​of physical properties that are affected by the measurement humidity are the results of measurements at standard humidity, unless otherwise specified.

[0015] In this specification, the humidity under normal conditions means a relative humidity of about 40%, 50%, or 60%.

[0016] As used herein, unless otherwise specified, the term "alkyl" or "alkyl group" refers to an alkyl or 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. Such alkyl or alkyl groups may be linear, branched, or cyclic. Such alkyl or alkyl groups may be optionally substituted with one or more substituents.

[0017] Unless otherwise specified, the term "alkylene" or "alkylene group" as used herein refers to a functional group in which two hydrogen atoms have been removed from an alkane and linked to another object, and in this 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 one or more substituents.

[0018] Unless otherwise specified, the term "alkylidene" or "alkylidene group" as used herein refers to a functional group in which two hydrogen atoms have been removed from an alkane and the functional group is linked to another object, and in this case 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 one or more substituents.

[0019] As used herein, the term "hydrogel polymer" or "hydrogel polymer composition" refers to a water-absorbing material comprising a polymer; such a material may also be referred to simply as a hydrogel.

[0020] As used herein, the term "water-absorbent material" refers to a material that exhibits at least one of the properties of moisture content, centrifuge retention capacity (CRC), and absorbent capacity under pressure (AUP), as defined herein.

[0021] As used herein, the term "biodegradable material" refers to a material that exhibits a degree of biodegradation as defined herein.

[0022] The present invention relates to a polymer composition, which may be a water-absorbing material as described above and at the same time a biodegradable material.

[0023] As used herein, the term "polymer composition" refers to a material containing a polymer. The term "composition" refers to a material containing two or more components. The two or more components do not necessarily have to be different types of components. For example, a polysaccharide component, as described below, may consist of two or more molecules of a polysaccharide polymer. In such cases, a material containing only the polysaccharide component may be referred to as a polymer composition. Furthermore, the two or more components contained in a polymer composition may physically or chemically interact or react with each other, or may simply be mixed without any interaction or reaction. The term "polymer" refers to a substance formed by two or more units linked by a covalent bond. For example, the polymer may be 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. While there are no limitations on the molecular weight range, the weight average molecular weight (Mw) of the polymer may be about 500 g / mol or more. There is no particular upper limit to the weight average molecular weight, and for example, the weight average molecular weight of the polymer may be about 1,000,000 g / mol or less.

[0024] The weight average molecular weight is a value measured by the method described in "4. Measurement of molecular weight of polysaccharide component" in the Examples section of this specification.

[0025] In one example, the lower limit of the polymer content in the polymer composition 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 content may be greater than or equal to any one of the lower limits; or greater than or equal to any one of the lower limits and less than or equal to any one of the upper limits. The polymer content is based on the solid content; therefore, if the polymer composition contains a solvent, the content is the percentage by weight of the entire polymer composition excluding the solvent.

[0026] The polymer composition can include a polysaccharide component.

[0027] The term "polysaccharide component" refers to a component composed of one or more polysaccharides. That is, the polysaccharide component includes only polysaccharides. The polysaccharide component may include one or more polysaccharides. The category of two or more polysaccharides may include polysaccharides that have different chemical structures (e.g., types of repeating units) and / or polysaccharides that have the same or substantially similar chemical structures but different physical properties such as molecular weight.

[0028] The term "polysaccharide" has the meaning known in the art. Generally, polysaccharide refers to a polymer molecule in which two or more units are linked by a covalent bond. The covalent bond linking the units may be, for example, a glycosidic bond. The polysaccharide is a polymer molecule, i.e., a polymer, and may have a weight-average molecular weight within the ranges mentioned above.

[0029] 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 commonly 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.

[0030] In one example, the polymer composition may be in the form of powder or particles formed through a pulverization process or the like.

[0031] The polymer composition may contain only the polysaccharide component as a polymer, or may contain other components in addition to the polysaccharide component. Within the polymer composition, the polysaccharide component may exist in a polymerized and crosslinked state.

[0032] Examples of other components that may be included in the polymer composition together with the polysaccharide include, but are not limited to, a crosslinking agent that crosslinks the polysaccharide or a polymer different from the polysaccharide.

[0033] In one example, the lower limit of the weight percentage of the polysaccharide component in the polymer composition may be about 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, 92 wt%, 94 wt%, 96 wt%, or 98 wt%, and the upper limit may be about 100 wt%, 98 wt%, 96 wt%, 94 wt%, 92 wt%, or 90 wt%. The weight percentage may be greater than or equal to any one of the lower limits; or may be greater than or equal to any one of the lower limits and less than or equal to any one of the upper limits. The weight percentage is based on the solids content. Therefore, if the polymer composition contains a solvent, the weight percentage is the weight of the entire polymer composition excluding the solvent.

[0034] The higher the proportion of the polysaccharide component in the polymer composition, the greater the biodegradability of the polymer composition. By using a specific type of polysaccharide component as the polysaccharide component, appropriate crosslinking can be achieved, and the crosslinked material can simultaneously exhibit the desired water absorption capacity and biodegradability.

[0035] When the polymer composition is a water-absorbing material, the lower limit of the water content of the polymer composition may be about 40%, 45%, 50%, or 55% by weight, and the upper limit may be about 70%, 65%, or 60% by weight. The water content may be within a range equal to or greater than any one of the lower limits; or within a range equal to or greater than any one of the lower limits and equal to or less than any one of the upper limits.

[0036] The moisture content is the ratio of the moisture content of the polymer composition to the total weight of the polymer composition to be measured, and can be calculated based on the weight of the polymer composition containing moisture and the weight of the dried polymer composition. For example, the moisture content can be calculated based on the weight loss due to evaporation of moisture in the polymer composition during the process of drying a crumb-state polymer composition using infrared heating. The drying process for measuring the moisture content can include heating the polymer composition to about 50°C at room temperature and then vacuum drying for about 6 hours while maintaining the temperature at 50°C. The polymer composition can exhibit the moisture content before or after crosslinking.

[0037] When the polymer composition is an absorbent material, the lower limit of the centrifuge retention capacity (CRC) of the polymer composition according to EDANA (European Disposables and Nonwovens Association) method WSP 241.3 may be about 12 g / g, 13 g / g, 14 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, 35 g / g, 34 g / g, 33 g / g, or 32 g / g. The centrifuge retention capacity may be in a range equal to or greater than any one of the lower limits; or in a range equal to or greater than any one of the lower limits and equal to or less than any one of the upper limits. The centrifuge retention capacity is evaluated by the method described in "1. Evaluation of Centrifuge Retention Capacity (CRC)" in the Examples section of this specification. The polymer composition can exhibit the centrifuge retention capacity before or after crosslinking.

[0038] When the polymer composition is a water-absorbent material, the lower limit of the absorbent capacity under pressure (AUP) of the polymer composition at 0.7 psi according to EDANA (European Disposables and Nonwovens Association) method WSP 242.3 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, or 5.5 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 under pressure may be greater than or equal to any one of the lower limits; or may be greater than or equal to any one of the lower limits and less than or equal to any one of the upper limits. The absorbency under pressure is evaluated by the method described in "2. Evaluation of Absorbency under Pressure (AUP)" in the Examples section of this specification. The polymer composition can exhibit the absorbency under pressure before or after crosslinking.

[0039] When the polymer composition exhibits at least one of the above-described properties of moisture content, centrifuge water retention capacity, and water absorption capacity under pressure, the material can be defined as a water-absorbing material.

[0040] The polymer composition can exhibit excellent biodegradability. For example, the polymer composition can be both a water-absorbing material and a biodegradable material. For example, the lower limit of the biodegradability of the polymer composition can be approximately 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 can be approximately 100%, 98%, 96%, 94%, 92%, 90%, 88%, 86%, 84%, 82%, 80%, 78%, or 76%. The biodegradability can be within a range that is equal to or exceeds any one of the lower limits; or it can be within a range that is equal to or exceeds any one of the lower limits and equal to or exceeds any one of the upper limits. The biodegradability is evaluated by the method described in "3. Measurement of biodegradability" in the Examples section of this specification. The polymer composition can exhibit the biodegradability before or after crosslinking.

[0041] The polymer composition can exhibit excellent water absorption and biodegradability at the same time.

[0042] Such a polymer composition can be realized by using a polysaccharide component, as described below, as the polysaccharide component. Typically, polysaccharide-based polymer materials have excellent biodegradability but poor water absorption capacity and poor crosslinking efficiency for use as a water-absorbent material. Therefore, to form a water-absorbent material using a polysaccharide-based material, other components are generally blended with the polysaccharide rather than using only the polysaccharide. However, when a specific type of polysaccharide component is used as the polysaccharide component, an efficient crosslinking rate, as described below, can be ensured even with the polysaccharide component alone, and the polymer composition can simultaneously exhibit excellent water absorption capacity and biodegradability after crosslinking.

[0043] As mentioned above, polysaccharides are polymeric substances in which two or more units are linked by covalent bonds such as glycosidic bonds, and representative known polysaccharides include starch (green powder), dextrin, and chitosan.

[0044] The polysaccharide component may include one or more selected from the group consisting of starch (green powder), dextrin, and chitosan.

[0045] In one example, the polysaccharide component may include amylose and amylopectin.

[0046] 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 chain structure, while amylopectin has relatively short, highly branched chains. Amylose crystallizes more easily than amylopectin, and amylopectin has a relatively high solubility in water compared to amylose.

[0047] In this specification, it has been confirmed that the ratio of amylose to amylopectin in the polysaccharide component and the molecular weight of the polysaccharide component are closely related to the water absorption capacity and biodegradability of the polymer composition.

[0048] As the proportion of amylopectin in the polysaccharide component decreases and the proportion of amylose increases, the biodegradability of the material increases, but the water absorption capacity tends to decrease slightly. Also, as the molecular weight of the polysaccharide component increases, the biodegradability of the material decreases, but the water absorption capacity tends to increase. Therefore, by controlling the amounts of amylose and amylopectin and the molecular weight of the polysaccharide component, it is possible to obtain a material with excellent biodegradability and water absorption capacity.

[0049] As a result, the polymer composition may have F in a predetermined range according to the following formula 1:

[0050]

number

[0051] In Equation 1, Ap is the proportion of amylopectin in the polysaccharide component, Am is the proportion of amylose in the polysaccharide component, and Mw is the weight average molecular weight of the polysaccharide component.

[0052] F in Equation 1 is a factor determined by the relationship between 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.

[0053] Polysaccharide components in which the ratio of amylose / amylopectin and molecular weight are controlled so that F in Equation 1 falls within the range described below can be efficiently crosslinked to form materials with excellent water absorption capacity and biodegradability.

[0054] In Equation 1, Ap and Am are the proportions of amylopectin and amylose measured by the method described in "5. Measurement of amylopectin and amylose content in polysaccharide components" in the Examples section of this specification, and their units are %.

[0055] In Equation 1, Mw is the weight-average molecular weight of the polysaccharide component, and is a value measured by the method described in "4. Measurement of molecular weight of polysaccharide component" in the Examples section of this specification, and its unit is g / mol.

[0056] The lower limit of F in Formula 1 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 in Formula 1 may be within a range that is equal to or greater than any one of the lower limits listed above; or it may be within a range that is equal to or greater than any one of the lower limits listed above and equal to or less than any one of the upper limits listed above.

[0057] Within this range, the polysaccharide component can be efficiently crosslinked to form a polymer composition with excellent water absorption capacity and biodegradability.

[0058] The ranges of Mw, Am and Ap in Equation 1 can be adjusted to appropriate levels.

[0059] In one 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, / mol, 2,000,000g / 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, 10,00 0,000g / 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 ,000,000g / 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, 160,000,0 The upper limit may be about 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, 150,000,000 g / mol, 100,000,000 g / mol, 90,000,000g / mol, 80,000,000g / mol, 70,000,000g / mol, 60,000,000g / mol, 50,000,000g / mol, 40,000,000 g / mol, 30,000,000g / mol, 20,000,000g / mol, 10,000,000g / mol, 9,000,000g / mol, 8,000,000g / mol, 7,00 The Mw may be about 0,000 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 in a range that is greater than or equal to any one of the lower limits listed above; or less than or equal to any one of the upper limits listed above; or greater than or equal to any one of the lower limits listed above and less than or equal to any one of the upper limits listed above.

[0060] The lower limit of Ap in Formula 1 may be about 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%, 25%, or 20%. Ap may be within a range that is equal to or greater than any one of the above lower limits; or within a range that is equal to or greater than any one of the above upper limits; or within a range that is equal to or greater than any one of the above lower limits and equal to or less than any one of the above upper limits.

[0061] The lower limit of Am in Formula 1 may be about 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%, 25%, or 20%. Am may be within a range that is equal to or greater than any one of the lower limits described above; or within a range that is equal to or greater than any one of the upper limits described above; or within a range that is equal to or greater than any one of the lower limits described above and equal to or less than any one of the upper limits described above.

[0062] In one example, the sum of Am and Ap in the polysaccharide component may be 100%.

[0063] In one example, when the polysaccharide of the polysaccharide component is a modified polysaccharide described below, the functional group introduced into the modified polysaccharide may be introduced into either one of the amylose and the amylopectin, or may be introduced into both of them. The reaction to introduce the functional group described below can occur from both the amylose and the amylopectin, but more efficient modification may be possible when the content of amylopectin is higher than the content of amylose.

[0064] As the polysaccharide component, an appropriate type can be selected and used from the above-mentioned polysaccharides, as long as it contains at least the polysaccharides containing amylose and amylopectin.

[0065] One or more known polysaccharides may be combined to form a polysaccharide component so that F in formula 1 falls within the above-mentioned range, and this polysaccharide component may be applied to the polymer composition.

[0066] Among known polysaccharides, starch can be commonly used. When starch is used, starch having a gelatinization temperature in the range of about 50°C to 90°C and a peak viscosity (BU) in the range of 50 to 1000 can be used.

[0067] The starch may be any known starch without any particular limitation, and may be, for example, one or more types selected from potato starch, corn starch, rice starch, wheat starch, tapioca starch, polymeric starch, and the like.

[0068] Such polysaccharides may comprise at least two or more monosaccharide units linked by a covalent bond (e.g., glycosidic bond), where the monosaccharide units may be exemplified by the biomolecules described above, including, but not limited to, glucose, galactose, fructose, xylose, glucosamine, and N-acetylglucosamine.

[0069] At least one of the units contained in the polysaccharide may be a modified monosaccharide unit, which means a unit into which a functional group not present in the original unit has been introduced by chemical treatment.

[0070] Polysaccharides in which such modified polysaccharide units are present may be referred to as modified polysaccharides.

[0071] The polysaccharide component may include the modified polysaccharide.

[0072] In one example, the functional group introduced into the modified monosaccharide unit can be represented by the following Chemical Formula 1:

[0073] [ka]

[0074] In the chemical formula, M1 is hydrogen or a metal, and when M1 is a metal, the O-M1 bond is an ionic bond.

[0075] The functional group of Chemical Formula 1 may be introduced into the unit by bonding the oxygen atom on the left side of Chemical Formula 1 to the backbone of the unit.

[0076] The carbon-carbon double bond in the functional group of Chemical Formula 1 may be present in the polymer in a state where the double bond is maintained, or may be present in the polymer in a state where the double bond is participating in a crosslinking bond.

[0077] In Chemical Formula 1, M1 is hydrogen or a metal. The type of the metal is not particularly limited, and may generally be an alkali metal such as lithium, sodium, potassium, or cesium.

[0078] The polysaccharide may simultaneously have a functional group in which M1 is hydrogen and a functional group in which M1 is a metal in the above Chemical Formula 1.

[0079] The functional group can be introduced by reacting the polysaccharide with an unsaturated dicarboxylic acid or anhydride thereof to substitute the hydroxy group present in the polymer unit with the functional group. Examples of the dicarboxylic acid or anhydride include, but are not limited to, maleic acid or maleic anhydride, and salts of maleic acid can also be used.

[0080] The lower limit of the substitution rate of the functional group of Chemical Formula 1 in the polysaccharide component may be about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%, and the upper limit thereof may be about 300%, 295%, 290%, 285%, 280%, 275%, 270%, 265%, 260%, 255%, 250%, 245%, 240%, 235%, 230%, It may be about 225%, 220%, 215%, 210%, 205%, 200%, 195%, 190%, 185%, 180%, 175%, 170%, 165%, 160%, 155%, 150%, 145%, 140%, 135%, 130%, 125%, 120%, 115%, 110%, 105%, 100%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, or 40%. The substitution rate may be within a range equal to or greater than any one of the lower limits described above; or equal to or less than any one of the upper limits described above; or equal to or greater than any one of the lower limits and equal to or less than any one of the upper limits described above. Within this range of substitution rate, crosslinking of the polysaccharide component can proceed effectively, and the physical properties (e.g., water absorption capacity and / or biodegradability) of the resulting polymer material can be stably ensured.

[0081] As used herein, the substitution rate is a value indicating the degree to which hydroxyl groups present in units contained in a polysaccharide component have been substituted with a predetermined functional group (e.g., the functional group of Chemical Formula 1), and is the average value of the degree of substitution 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 Chemical Formula 1, the substitution rate for the unit is 300%. However, the substitution rate of a polysaccharide is the average value of the degree of substitution for each unit present in the polysaccharide. For example, if a polysaccharide containing five glucose units has the substitution rates of 100%, 0%, 200%, 300%, and 100%, the substitution rate of the polysaccharide is 140%, which is the average value. Such substitution rates are determined based on the average value of the degree of substitution for 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 substitution rate can be confirmed. If necessary, the polysaccharide before modification can be 1 The substitution rate can be calculated taking into account the results of H NMR analysis. 1 Methods for quantifying functional groups through 1 H NMR analysis are well known.

[0082] In one example, the unit containing the functional group of Formula 1 may be a unit represented by Formula 2 below.

[0083] [ka]

[0084] In Chemical Formula 2, R1 is a hydroxy group, an amino group, or an alkylcarbonylamino group, L1 is an alkylene group or an alkylidene group, and M1 is hydrogen or a metal.

[0085] If M1 in Chemical Formula 2 is a metal, the O-M1 bond in Chemical Formula 2 may be an ionic bond.

[0086] The specific types of metals in M1 in Chemical Formula 2 are the same as those described in Chemical Formula 1.

[0087] The specific types of alkyl, alkylene, or alkylidene groups in Chemical Formula 2 are the same as those defined above.

[0088] As described in Chemical Formula 1, the carbon-carbon double bond of the functional group of Chemical Formula 2 may exist in a state where the double bond is maintained, or may exist in a polymer in a state where the double bond participates in a crosslinking bond.

[0089] The polymer may simultaneously contain functional groups in which M1 in Chemical Formula 2 is hydrogen and functional groups in which M1 is a metal.

[0090] In chemical formula 2, when R1 is a hydroxy group, it generally represents a case where the unit is derived from a so-called glucose unit; when R1 is an amino group, it generally represents a case where the unit is derived from a so-called glucosamine unit; and when R1 is an alkylcarbonylamino group, it generally represents a case where the unit is derived from N-acetylglucosamine.

[0091] In one example, the functional group introduced into the modified polysaccharide unit may be, for example, a functional group represented by the following Chemical Formula 3:

[0092] [ka]

[0093] In Chemical Formula 3, L2 is an alkylene group or an alkylidene group, M2 is hydrogen or a metal, and when M2 is a metal, the O-M2 bond is an ionic bond.

[0094] The specific types of alkylene or alkylidene groups in Chemical Formula 3 are the same as those defined above.

[0095] The functional group of the formula 3 may be introduced into the unit by bonding L2 on the left side of the formula 3 to the backbone of the unit.

[0096] In Chemical Formula 3, M2 is hydrogen or a metal. The type of the metal is not particularly limited, and may generally be an alkali metal such as lithium, sodium, potassium, or cesium.

[0097] The polymer may simultaneously contain functional groups in which M2 in Chemical Formula 3 is hydrogen and functional groups in which M2 is a metal.

[0098] The functional group can be introduced by reacting the polysaccharide with an acetic acid chloride such as chloroacetic acid to substitute the hydroxy group present in the polymer unit with the functional group.

[0099] The lower limit of the substitution rate of the functional group of Chemical Formula 3 in the polysaccharide component may be about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%, and the upper limit thereof may be about 300%, 295%, 290%, 285%, 280%, 275%, 270%, 265%, 260%, 255%, 250%, 245%, 240%, or 255%. %, 235%, 230%, 225%, 220%, 215%, 210%, 205%, 200%, 195%, 190%, 185%, 180%, 175%, 170%, 165%, 160%, 155%, 150%, 145%, 140%, 135%, 130%, 125%, 120%, 115%, 110%, 105%, 100%, 95%, 90%, 85%, 80%, 75%, or 70%. The substitution rate may be within a range that is equal to or exceeds any one of the lower limits described above; or within a range that is equal to or exceeds any one of the lower limits described above and equal to or exceeds any one of the upper limits described above. When the functional group of Chemical Formula 3 is present, crosslinking of the polysaccharide component can proceed effectively within the range of the substitution rate, and the physical properties (e.g., water absorption capacity and / or biodegradability) of the obtained polymer material can be stably ensured.

[0100] The substitution rate is defined as the same as that for the functional group of Chemical Formula 1, and similarly, the substitution rate for the polysaccharide component is defined as the same as that for the functional group of Chemical Formula 1. 1 This can be confirmed through H NMR analysis.

[0101] In one example, the unit containing the functional group of Formula 3 may be a unit represented by Formula 4 below.

[0102] [ka]

[0103] In Chemical Formula 4, R2 is a hydroxy group, an amino group, or an alkylcarbonylamino group, L2 and L3 are each independently an alkylene group or an alkylidene group, and M2 is hydrogen or a metal.

[0104] When M2 is a metal, the O-M2 bond is an ionic bond.

[0105] The specific types of metals of M2 in Formula 4 are the same as those described in Formula 3.

[0106] In Chemical Formula 4, the specific types of alkyl, alkylene, or alkylidene groups are the same as those defined above.

[0107] In the polysaccharide, a functional group in which M2 is hydrogen in the above formula 4 and a functional group in which M2 is a metal may exist simultaneously.

[0108] The polysaccharide contained in the polymer composition may have either one of the functional group of Chemical Formula 1 and the functional group of Chemical Formula 3, or both of them may be present at the same time.

[0109] Therefore, either one of the units of Formula 2 and the units of Formula 4, or both, may be present in the polysaccharide component of the polymer composition.

[0110] In one example, the polysaccharide may be contained in the polymer composition in a crosslinked state. Therefore, the polymer composition may further contain a crosslinking agent. However, as long as the crosslinking of the polymer composition is due to self-crosslinking as described below, the crosslinking agent does not necessarily have to be contained in the polymer composition.

[0111] In one example, the crosslinked state of the polysaccharide component may be self-crosslinked. The term "self-crosslinked" may refer to crosslinking between polysaccharides within the polysaccharide component without the use of a separate crosslinking agent or crosslinking with minimal use of a crosslinking agent.

[0112] Crosslinking in this manner can provide a polymer composition that is both excellent in water absorption and biodegradability. In general, polysaccharides have low crosslinking efficiency, and even when crosslinkable functional groups are introduced, efficient crosslinking is not achieved. However, in the present invention, the self-crosslinking can be achieved effectively by using the specific polysaccharides described above.

[0113] When the polysaccharide component is self-crosslinked, the upper limit of the weight ratio of the crosslinker relative to 100 parts by weight of the polysaccharide component in the polymer composition may be about 10 parts by weight, 9 parts by weight, 8 parts by weight, 7 parts by weight, 6 parts by weight, 5 parts by weight, 4 parts by weight, 3 parts by weight, 2 parts by weight, 1 part by weight, 0.5 parts by weight, 0.1 parts by weight, 0.05 parts by weight, 0.01 parts by weight, 0.005 parts by weight, or 0.001 parts by weight, and the lower limit may be about 0 parts by weight. The content may be less than or equal to any one of the upper limits; or may be greater than or equal to or exceeding any one of the lower limits and less than or equal to any one of the upper limits. Crosslinking performed using a crosslinker in the above-mentioned ratios is also considered to be crosslinking that falls within the category of self-crosslinking.

[0114] The self-crosslinking may be carried out in any manner, for example, in the presence of an oxidizing agent such as ammonium persulfate or other initiators.

[0115] For example, when a functional group of Formula 1 is present in a polysaccharide component, in the above crosslinking environment, crosslinking or polymerization by the functional group of Formula 1 present in the polysaccharide and crosslinking or polymerization or grafting between the radical generated by oxidation with the oxidizing agent and the functional group of Formula 1 may occur, resulting in crosslinking.

[0116] In another example, the crosslinking may be performed using a crosslinking agent. In this case, the crosslinking agent is not particularly limited and may be a crosslinking agent used as a so-called internal crosslinking agent or an external crosslinking agent in the preparation of crosslinked polyacrylic acid that is generally used in so-called SAP (Superabsorbent polymer), or may be both of them.

[0117] Known examples of such crosslinking agents include polyethylene glycol diacrylate, N,N'-dimethylenebisacrylamide, trimethylolpropane tri(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol (meth)acrylate, propylene glycol di(meth)acrylate, polypropylene glycol (meth)acrylate, butanediol di(meth)acrylate, butylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, hexanediol di(meth)acrylate, triethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, dipentaerythritol pentaacrylate, glycerin tri(meth)acrylate, pentaerythritol tetraacrylate, triarylamine, ethylene glycol diglycidyl ether, propylene glycol, glycerin, and / or ethylene carbonate. In the present invention, an appropriate crosslinking agent can be selected from the above-mentioned known crosslinking agents and used as needed.

[0118] In order to perform more effective crosslinking and ensure desired physical properties, an organic acid having two or more carboxyl groups or an anhydride of the organic acid may be used as the crosslinking agent in addition to the above crosslinking agents.

[0119] When the crosslinking agent is applied, ester bonds formed by reaction of the carboxyl groups of the crosslinking agent with the hydroxyl groups in the polysaccharide component can be present in the polymer composition.

[0120] In this case, the type of organic acid is not particularly limited, but for example, an organic acid having a molecular weight (molar mass) in the range of about 90 to 300 g / mol or about 100 to 250 g / mol can be used. The lower limit of the number of carboxyl groups contained in the organic acid may be about 2 or 3, and the upper limit may be about 10, 9, 8, 7, 6, 5, 4, or 3. The number of carboxyl groups may be equal to or greater than any one of the above-mentioned lower limits; or may be equal to or greater than any one of the above-mentioned lower limits and equal to or less than any one of the above-mentioned upper limits.

[0121] Examples of such organic acids include, but are not limited to, citric acid, succinic acid, pimelic acid, and adipic acid. The organic acids or anhydrides thereof may be used as the crosslinking agent.

[0122] When the crosslinking agent is used, the upper limit of the weight ratio of the crosslinking agent relative to 100 parts by weight of the polysaccharide component may be about 10 parts by weight, 9 parts by weight, 8 parts by weight, 7 parts by weight, 6 parts by weight, 5 parts by weight, 4 parts by weight, or 3 parts by weight, and the lower limit may be about 0.5 parts by weight, 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, or 3 parts by weight. The content may be within a range that is equal to or greater than any one of the lower limits; or within a range that is equal to or greater than any one of the upper limits; or within a range that is equal to or greater than any one of the lower limits and equal to or less than any one of the upper limits. The content range of the crosslinking agent may be a combination of any one of the upper limits and any one of the lower limits.

[0123] The polymer composition may be subjected to additional treatment, such as surface cross-linking or pulverization, etc. In such a case, the polymer composition may contain the polysaccharide component in a cross-linked state and in a particulate form, or may contain the polysaccharide component in a cross-linked state and in a particulate form with a surface cross-linking agent bound to the surface.

[0124] The polymer composition exhibits excellent water absorption and biodegradability at the same time, and can be used in a variety of applications.

[0125] For example, the polymer material may be used as a water-absorbing material for hygiene products such as diapers and sanitary napkins, or other applications requiring water absorption. If necessary, the polymer composition may be subjected to an additional crosslinking, surface treatment, or physical grinding process to enhance its efficiency in use as the hygiene product or water-absorbing material.

[0126] The present invention therefore relates to absorbent materials or sanitary articles (such as diapers and sanitary napkins) comprising said polymer compositions.

[0127] The specific method of applying the polymer composition to form the water-absorbing material or sanitary product is not particularly limited, and for example, the same method of applying an existing SAP to form the water-absorbing material or sanitary product may be used. [Effects of the Invention]

[0128] The present invention can provide a polymer composition having excellent biodegradability and water absorption capacity, and uses thereof. [Brief explanation of the drawings]

[0129] [Figure 1] FIG. 1 shows the results of 1H NMR analysis of the polysaccharides produced in the production examples. [Figure 2] FIG. 2 shows the results of 1H NMR analysis of the polysaccharides produced in the production examples. [Figure 3]FIG. 3 shows the results of 1H NMR analysis of the polysaccharides produced in the production examples. [Figure 4] FIG. 4 shows the results of 1H NMR analysis of the polysaccharides produced in the production examples. [Figure 5] FIG. 5 shows the results of 1H NMR analysis of the polysaccharides produced in the production examples. DETAILED DESCRIPTION OF THE INVENTION

[0130] 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.

[0131] 1. Evaluation of Centrifuge Retention Capacity (CRC)

[0132] Centrifugal water retention capacity (CRC) was measured according to EDANA (European Disposables and Nonwovens Association) WSP 241.3. Approximately 0.2 g (W0) of the polymer composition was placed in a nonwoven envelope, 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 envelope was centrifuged at 250 G for 3 minutes to remove water, after which the mass (g, W2) of the envelope was measured. The same procedure was performed on an identical nonwoven envelope without the polymer composition, and the mass (g, W1) was measured.

[0133] The measurement results were substituted into the following formula A to calculate CRC (g / g).

[0134] The evaluation was carried out under constant temperature and humidity conditions (23±1° C., relative humidity: 50±10%).

[0135] [Formula A] CRC(g / g)={[W2(g)-W1(g)] / W0(g)}-1

[0136] 2. Evaluation of Absorbency under Pressure (AUP)

[0137] The water absorption capacity under pressure (AUP, 0.7 psi) of a polymer composition was measured according to the EDANA (European Disposables and Nonwovens Association) standard WSP 242.3. A 400-mesh stainless steel mesh was attached to the bottom of a plastic cylinder with an inner diameter of approximately 60 mm. Approximately 0.90 g (W0) of the polymer composition was uniformly spread on the 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 placed on top of the mesh to prepare a measuring device. The piston had an outer diameter slightly smaller than 60 mm and was installed so that it did not form a gap with the inner wall of the cylinder and could move up and down. The weight (unit: g) of the measuring device (W3) was measured.

[0138] A glass filter approximately 90 mm in diameter and 5 mm thick was placed inside a petri 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 sheet of filter paper approximately 90 mm in diameter was placed on top of the filter. 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.

[0139] The measured weights were substituted into the following formula B to calculate the water absorption capacity under pressure (AUP) (g / g).

[0140] [Formula B] AUP(g / g) = [W4(g) - W3(g)] / W0(g)

[0141] 3. Measurement of biodegradability

[0142] 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 a polymer composition by quantifying the amount of carbon dioxide released by microbial metabolism of the material. The polymer composition was subjected to composting conditions according to the standard and the biodegradation was measured for six months. 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 rate can be calculated using the following formulas C and D, respectively.

[0143] [Formula C] Theoretical carbon dioxide generation (ThCO2, g / container) = M T O T ×C T O T ×(44 / 12)

[0144] In formula C, M T O T is the amount (g) of total dry solids of the test material (polymer composition) added to the compost at the start of the measurement, and C T O T means the percentage of organic carbon (g / g) contained in the total dry solids of the test material.

[0145] [Formula D] Biodegradation (%)=[{(CO2) T -(CO2) B} / ThCO2]×100

[0146] In Equation D, (CO2)T is the cumulative amount of carbon dioxide evolved from the composting vessels in the test material (g / vessel), (CO2)B is the average cumulative amount of carbon dioxide evolved from the inoculum vessels (g / vessel), and ThCO2 is the theoretical carbon dioxide evolution determined from Equation C above.

[0147] 4. Molecular weight measurement of polysaccharide components

[0148] The molecular weight of the polysaccharide component was evaluated by the following method.

[0149] (1) Preparation of mobile phase

[0150] Mobile phase A was prepared by filtering 1000 mL of 150 mM NaNO3 aqueous solution containing 0.02 wt% NaN3 using a solvent clarification system (Millipore Millisolve Kit, MilliporeSigma).

[0151] (2) Preparation of sample solution

[0152] 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.

[0153] (3) GPC (Gel Permeation Chromatography) / MALS (Multi-Anglue Light Scattering Detection) conditions

[0154] Using the sample solution and mobile phase A, the molecular weight was evaluated by the following method.

[0155] Measuring instrument: Agilent GPC (Agilent 1200 series, US)

[0156] Stationary phase: Shodex OH-Pak 804 column and Shodex OH-Pak 80 column connected

[0157] Mobile phase: A; 0.02% NaN3, 150mM NaNO3 aqueous solution = 100 (v / v%)

[0158] Flow rate: 0.4mL / min

[0159] Stationary phase temperature: 25℃

[0160] Injection volume: 100μl (0.45μm filtered)

[0161] Analysis time: 120 minutes

[0162] 5. Measurement of amylopectin and amylose content in polysaccharide components

[0163] The contents of amylopectin and amylose in the polysaccharide components were evaluated according to the method described in the paper (Potato Research 31 (1988) 241-246).

[0164] First, approximately 5 mg of starch sample was dissolved in approximately 1 mL of sterile water to prepare a sample (Step 1), and then heated in a water bath at 95°C for approximately 15 minutes (Step 2).

[0165] Then, about 20 μl of the sample was placed in a cuvette (step 3), and about 980 μl of iodine solution was added and mixed (step 4).

[0166] Then, the absorbance of the sample mixed with the iodine solution was measured at wavelengths of 525 nm and 700 nm and recorded (Step 5). The absorbance was measured using an OPTIZEN POP model manufactured by KLAB.

[0167] Approximately 20 μL of water was placed in another cuvette, and 980 μL of iodine solution was added and mixed (Step 6). The absorbance of the solution in Step 6 was measured at wavelengths of 525 nm and 700 nm in the same manner as in Step 5 and recorded (Step 7).

[0168] The absorbance obtained in step 7 was subtracted from the absorbance obtained in step 5 to determine the percentage of amylose (step 8) using the following formula E:

[0169]

number

[0170] In the equation E, PA is the percentage of amylose, and OD 700 is the absorbance at 700 nm measured in step 5 minus the absorbance at 700 nm measured in step 7, and OD 525 is the absorbance at 525 nm measured in step 5 minus the absorbance at 525 nm measured in step 7.

[0171] <Production Example 1>

[0172] Starch containing a modified monosaccharide unit of the following chemical formula A (compound A) was prepared by the following method. The modified monosaccharide unit of the following chemical formula A is a monosaccharide unit into which a functional group derived from sodium acetate has been introduced.

[0173] [ka]

[0174] The starch used as the raw material had a weight-average molecular weight (Mw) of approximately 180,000,000 g / mol, an amylopectin content of approximately 81%, and an amylose content of approximately 19%. The amylose content was determined using formula E, and the amylopectin content was calculated by subtracting the amylose content from 100%.

[0175] The starch, isopropyl alcohol (IPA), and an aqueous NaOH solution (concentration: approximately 40%) were mixed in a 500 mL round bottom flask (RBF) and stirred at room temperature for approximately 20 minutes. The weight ratio of the mixture was 1:4:0.8 (starch:IPA:NaOH aqueous solution). Approximately 80 parts by weight of sodium monochloroacetate was then added to 100 parts by weight of the starch, and the mixture was heated to 60°C and stirred for approximately 1 hour. The mixture was then cooled to room temperature. After cooling to room temperature, the solvent was removed, the reactant was dissolved in water, and the mixture was precipitated in methanol to remove water-soluble impurities. The starch was recovered by filtration and dried in a vacuum oven at 40°C for approximately 12 hours to obtain the target compound (Compound A) in a solid phase.

[0176] The substitution rate of the obtained target product (compound A) 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. 1 The analysis was carried out at room temperature using a 1 H NMR spectrometer. 1 For 1 H NMR analysis, a Bruker Avance Neo instrument was used.

[0177] Specifically, 50 mg of the obtained solid phase target product (compound A) was mixed with 200 mg of a 30% D2DSO4 in D2O solution, and the mixture was stirred at 50°C for about 1 hour to induce a hydrolysis reaction. 1 H NMR analysis can be performed.

[0178] For the target substance (compound A) 1 The results of the H NMR analysis are shown in Figure 1. The substitution rate confirmed through the analysis was about 60%.

[0179] <Production Example 2>

[0180] A modified starch was produced in the same manner as in Production Example 1, except that the starch used had a weight-average molecular weight (Mw) of about 12,000,000 g / mol, an amylopectin content of about 75%, and an amylose content of about 25%.

[0181] The starch was confirmed in the same manner as in Preparation Example 1. 1 The results of 1 H NMR are shown in Figure 2 below, and the substitution rate confirmed from the results was about 60%.

[0182] <Production Example 3>

[0183] A modified starch was produced in the same manner as in Production Example 1, except that the starch used had a weight-average molecular weight (Mw) of about 2,000,000 g / mol, an amylopectin content of about 69%, and an amylose content of about 31%.

[0184] The starch was confirmed in the same manner as in Preparation Example 1. 1 The results of 1 H NMR are shown in FIG. 3, and the substitution rate confirmed from the results was about 70%.

[0185] <Production Example 4>

[0186] A modified starch was produced in the same manner as in Production Example 1, except that the starch used had a weight-average molecular weight (Mw) of about 920,000 g / mol, an amylopectin content of about 58%, and an amylose content of about 42%.

[0187] The starch was confirmed in the same manner as in Preparation Example 1. 1 The results of 1 H NMR are shown in FIG. 4, and the substitution rate confirmed from the results was about 52%.

[0188] <Production Example 5>

[0189] A modified starch was produced in the same manner as in Production Example 1, except that the starch used had a weight-average molecular weight (Mw) of about 450,000 g / mol, an amylopectin content of about 19%, and an amylose content of about 81%.

[0190] The starch was confirmed in the same manner as in Preparation Example 1. 1 The results of 1 H NMR are shown in FIG. 5, and the substitution rate confirmed from the results was about 50%.

[0191] <Production Example 6>

[0192] A modified starch was produced in the same manner as in Production Example 1, except that the starch used had a weight-average molecular weight (Mw) of about 140,000 g / mol, an amylopectin content of about 6%, and an amylose content of about 94%.

[0193] The starch was confirmed in the same manner as in Preparation Example 1. 1 As a result of 1 H NMR, the substitution rate was about 60%.

[0194] Example 1

[0195] The starch prepared in Preparation Example 1 was dissolved in distilled water, and a cross-linking agent (citric acid) was added in a ratio of about 3 parts by weight per 100 parts by weight of the starch. The mixture was stirred at room temperature for about 30 minutes, transferred to an iron tray, and dried in an oven at about 40°C for about 12 hours. The temperature was then raised to about 80°C and cross-linked for about 2 hours to prepare the desired polymer composition.

[0196] <Example 2>

[0197] A polymer composition was prepared in the same manner as in Example 1, except that the starch prepared in Preparation Example 2 was used.

[0198] Example 3

[0199] A polymer composition was prepared in the same manner as in Example 1, except that the starch prepared in Preparation Example 3 was used.

[0200] Example 4

[0201] A polymer composition was prepared in the same manner as in Example 1, except that the starch prepared in Preparation Example 4 was used.

[0202] <Example 5>

[0203] A polymer composition was prepared in the same manner as in Example 1, except that the starch prepared in Preparation Example 5 was used.

[0204] <Comparative Example 1>

[0205] A polymer composition was prepared in the same manner as in Example 1, except that the starch prepared in Preparation Example 6 was used.

[0206] The Mw, Am, and Ap values ​​of Formula 1 and the F value of the polymer compositions of the Examples and Comparative Examples, as well as the CRC, AUP, and biodegradability measured for each polymer composition, are summarized in Table 1. In Table 1, the unit of Mw is × 1,000 g / mol.

[0207] [Table 1]

[0208] From the results in Table 1, it can be seen that polymer compositions in which F in Formula 1 is 4 or more exhibit excellent water absorption properties and biodegradability at the same time, while in the case of Comparative Example 1 in which F is 3.9, biodegradability was ensured but water absorption properties were significantly reduced.

Claims

1. Contains polysaccharide components including amylose and amylopectin, The polysaccharide component is a polymer composition characterized in that F in the following formula 1 is 4 or more: [Equation 1] In Equation 1, Ap is the proportion of amylopectin in the polysaccharide component, Am is the proportion of amylose in the polysaccharide component, and Mw is the weight average molecular weight of the polysaccharide component.

2. 2. The polymer composition according to claim 1, characterized in that the centrifugation water retention capacity according to EDANA (European Disposables and Nonwovens Association) method WSP 241.3 is 12 g / g or more.

3. 2. The polymer composition according to claim 1, characterized in that the water absorption capacity under a pressure of 0.7 psi according to EDANA (European Disposables and Nonwovens Association) method WSP 242.3 is 1.5 g / g or more.

4. 2. The polymer composition according to claim 1, characterized in that the degree of biodegradation is 60% or more.

5. The polymer composition according to claim 1, wherein the polysaccharide component comprises at least one selected from the group consisting of starch, dextrin, and chitosan.

6. 2. The polymer composition of claim 1, wherein the Mw of Formula 1 is in the range of 200,000 g / mol to 1,000,000,000 g / mol.

7. 2. The polymer composition according to claim 1, wherein Ap in formula 1 is in the range of 5% to 95%.

8. 2. The polymer composition of claim 1, wherein the polysaccharide component comprises a polysaccharide containing a functional group of the following formula 1: 【Chemical 1】 Chemical formula: M １ is hydrogen or a metal, and the M １ When is a metal, O-M １ is an ionic bond, and the carbon-carbon double bond in Chemical Formula 1 can exist in a state where it participates in a cross-linking bond.

9. 2. The polymer composition of claim 1, wherein the polysaccharide component comprises a polysaccharide comprising units of the following formula 2: 【Chemistry 2】 M in chemical formula 2 １ is hydrogen or a metal, and the M １ When is a metal, O-M １ is an ionic bond, the carbon-carbon double bond of formula 2 can participate in a cross-linking bond, R １ is a hydroxy group, an amino group, or an alkylcarbonylamino group, and L １ is an alkylene group or an alkylidene group.

10. 2. The polymer composition of claim 1, wherein the polysaccharide component comprises a polysaccharide containing a functional group of the following formula 3: 【Chemistry 3】 In chemical formula 3, L ２ is an alkylene group or an alkylidene group, M ２ is hydrogen or a metal, and the M ２ When is a metal, O-M ２ The bond is an ionic bond.

11. 10. The polymer composition of claim 1, wherein the polysaccharide component comprises a polysaccharide comprising units of the following formula 4: 【Chemistry 4】 In chemical formula 4, R ２ is a hydroxy group, an amino group, or an alkylcarbonylamino group, and L ２ and L ３ are each independently an alkylene group or an alkylidene group, M ２ is hydrogen or a metal, M ２ When is a metal, O-M ２ The bond is an ionic bond.

12. The polymer composition of claim 1 , wherein the polysaccharide component is cross-linked.

13. 13. The polymer composition of claim 12, comprising ester linkages formed by reaction of hydroxy groups of the polysaccharide component with a crosslinking agent.

14. 13. The polymer composition of claim 12, wherein the polysaccharide component is cross-linked with a cross-linking agent, the cross-linking agent being an organic acid containing two or more carboxyl groups or an anhydride of the organic acid.

15. 15. The polymer composition of claim 14, wherein the organic acid has a molecular weight in the range of 90 g / mol to 300 g / mol and contains 2 to 10 carboxyl groups.

16. 15. The polymer composition according to claim 14, characterized in that the crosslinking agent is citric acid, citric anhydride, pimelic acid, pimelic anhydride, adipic acid, adipic anhydride, succinic acid or succinic anhydride.

17. 15. The polymer composition of claim 14, comprising 0.5 to 10 parts by weight of a crosslinking agent relative to 100 parts by weight of the polysaccharide component.

18. A water-absorbing material, characterized in that it comprises a polymer composition according to any one of claims 1 to 17.

19. Hygiene article, characterized in that it comprises a polymer composition according to any one of claims 1 to 17.

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