Marine biodegradable polymer compounds and marine biodegradable compositions

Abstract

This invention provides a polymer compound with excellent thermal and mechanical properties that undergoes biodegradation in the ocean, and a marine biodegradable composition using the same. [Solution] A marine biodegradable polymer compound comprising a polymer-type polyvalent anion and a monovalent cation, comprising a structural unit consisting of an oligomer and a linking group containing two or more monovalent anionic substituents.

Description

[Technical Field]

[0001] This invention relates to marine biodegradable polymer compounds and marine biodegradable compositions. [Background technology]

[0002] In recent years, environmental pollution (marine pollution) and adverse effects on ecosystems caused by microplastics have become a serious problem, and various initiatives to reduce the environmental burden have begun. Among these, the development and widespread use of biodegradable resins are attracting attention.

[0003] On the other hand, while general biodegradable resins exhibit high biodegradability in environments with many microorganisms responsible for decomposition, such as soil and sludge, they have the drawback of being difficult to decompose in environments with extremely low microbial concentrations, such as in the ocean (Non-Patent Literature 1). Furthermore, even for resins that have been reported to be biodegradable in the ocean, such as polycaprolactone (PCL) and polyhydroxyalkanoic acid (PHA), it has been found that the rate of decomposition varies greatly depending on the type of seawater. It has been reported that various factors such as the presence and number of decomposing bacteria in the seawater, salt concentration, pH, water temperature, dissolved oxygen concentration, and dissolved organic carbon content are influencing this (Non-Patent Literature 2).

[0004] Furthermore, although starch-based resins have been put into practical use and are on the market as biodegradable resins, single starch materials are significantly inferior in terms of physical properties. Therefore, most are mixed compositions with polyester resins that are difficult to biodegrade in the ocean, such as polybutylene adipate / terephthalate (PBAT) or polylactic acid (PLA). As a result, even starch-based resins tend to have significantly reduced biodegradability in the ocean.

[0005] Under these circumstances, there is a need to develop materials that maintain their physical properties, decompose reliably in any type of seawater, act as decomposition accelerators for resins that do not biodegrade easily in seawater, and reduce environmental impact. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Hideki Takada, "Current Status, International Trends, and Countermeasures Regarding Microplastic Pollution," Journal of the Japan Society of Waste Management and Resource Recycling, Vol. 29, No. 4, pp. 261-269, 2018. [Non-Patent Document 2] Akira Ebisu et al., "Decomposition of Biodegradable Plastics in Seawater," *Fisheries Engineering*, Vol. 40, No. 2, pp. 143-149, 2003. [Overview of the project] [Problems that the invention aims to solve]

[0007] This invention has been made in view of the above circumstances, and aims to provide a polymer compound that exhibits excellent thermal and mechanical properties and induces biodegradation in the ocean, and a marine biodegradable composition using the same. [Means for solving the problem]

[0008] As a result of diligent research to solve the aforementioned problems, the present inventors have found that marine biodegradable polymer compounds consisting of a polymer-type polyvalent anion comprising a repeating structure of a structural unit consisting of an oligomer containing repeating units and a linking group having two or more monovalent anionic substituents, and a monovalent cation, as well as polymer compounds in which the polymer-type polyvalent anion is bonded via a divalent or higher cation, exhibit excellent thermal and mechanical properties and high marine biodegradability.

[0009] Furthermore, by using this material in combination with resin, particularly biodegradable resin, we discovered that the material undergoes primary decomposition in seawater first, resulting in (1) the formation of pores in the resin material, increasing the specific surface area of ​​the resin and promoting the growth of microorganisms responsible for decomposition, and (2) the primary decomposition promoting secondary decomposition, i.e., biodecomposition by microorganisms. As a result, we found that the biodecomposition of the resin material in the ocean can be promoted, thus completing the present invention.

[0010] That is, the present invention provides the following marine biodegradable polymer compounds and marine biodegradable compositions. 1. A marine biodegradable polymer compound comprising a polymeric polyvalent anion containing a structural unit composed of an oligomer and a linking group containing two or more monovalent anionic substituents, and a monovalent cation. 2. The marine biodegradable polymer compound according to 1, wherein the monovalent cation is a proton, a monovalent metal cation or a monovalent organic cation. 3. The marine biodegradable polymer compound according to 1 or 2, wherein the oligomer has repeating units bonded by an ester bond, an amide bond or an ether bond. 4. The marine biodegradable polymer compound according to any one of 1 to 3, wherein the number average molecular weight of the oligomer is 400 to 10,000. 5. The marine biodegradable polymer compound according to any one of 1 to 4, wherein the number of structural units composed of the oligomer and the linking group is 2 to 50. 6. The marine biodegradable polymer compound according to any one of 1 to 5, wherein the content of the oligomer component is 30 to 99% by mass, and the content of the linking group component is 1 to 70% by mass. 7. The marine biodegradable polymer compound according to any one of 1 to 6, wherein the terminal is a carboxy group, a hydroxy group or an amino group. 8. The marine biodegradable polymer compound according to any one of 1 to 7, wherein the number average molecular weight is 800 to 200,000. 9. The marine biodegradable polymer compound according to any one of 1 to 8, wherein the monovalent anionic substituent is bonded to the linking group via 1 to 30 atoms. 10. The marine biodegradable polymer compound according to any one of 1 to 9, wherein the proportion of the monovalent cation other than the proton is 1 to 100%. 11. A marine biodegradable polymer compound in which the polymeric polyvalent anion containing a structural unit composed of an oligomer and a linking group containing two or more monovalent anionic substituents is bonded via a divalent or higher cation. 12. The marine biodegradable polymer compound according to 11, wherein the content of the divalent or higher cation is 1 to 100 eq / 10 5 g. A marine biodegradable composition containing any one of the marine biodegradable polymer compounds from 13.1 to 12. A marine biodegradation promoter containing the marine biodegradable composition of 13. A molded article obtained from the marine biodegradable composition of 13.

Advantages of the Invention

[0011] The marine biodegradable polymer compound of the present invention can achieve both good thermal and mechanical properties and biodegradability. Further, when the marine biodegradable polymer compound comes into contact with seawater, it gradually dissolves in seawater or exhibits hydrophilicity. Therefore, the composition and molded article containing this compound are promoted in biodegradation in the ocean and are useful for preventing marine pollution. Since the marine biodegradable polymer compound has marine biodegradability, the composition and molded article containing this compound are promoted in biodegradation in the ocean and are useful for preventing marine pollution. By using the marine biodegradation promoter containing the marine biodegradable polymer compound of the present invention, an environmentally friendly composition and molded article can be obtained.

Embodiments for Carrying Out the Invention

[0012] [Marine Biodegradable Polymer Compound] The first aspect of the marine biodegradable polymer compound of the present invention is a polymeric polyvalent anion comprising a structural unit composed of an oligomer and a linking group containing two or more monovalent anionic substituents, and a monovalent cation.

[0013] Examples of the monovalent anionic substituent include carboxylic acid anion (-COO - ), sulfonic acid anion (-SO3 - ), sulfate anion (-O-SO3 - ), phosphate anion (-P(=O)(OH)-O - ), etc. Among these, carboxylic acid anion, sulfonic acid anion, and sulfate anion are preferred, and carboxylic acid anion is particularly preferred from the viewpoint of environmental consideration.

[0014] The monovalent cation is preferably a proton, a monovalent metal cation, or a monovalent organic cation. Hereinafter, a compound in which the monovalent cation is only a proton will be referred to as marine biodegradable polymer compound A, and a compound in which the monovalent cation includes cations other than protons will be referred to as marine biodegradable polymer compound B.

[0015] The structural units are preferably bonded by ester bonds, amide bonds, or ether bonds. The content of structural units bonded by ester bonds, amide bonds, or ether bonds is preferably 5 mol% or more, more preferably 20 mol% or more, even more preferably 50 mol% or more, and most preferably 70 mol% or more, of the total structural units contained in the polymer-type polyvalent anion. If the content of structural units bonded by ester bonds, amide bonds, or ether bonds is within the above range, good biodegradability is achieved. Furthermore, the bonding is preferred in the order of ester bonds, amide bonds, and ether bonds, as this order makes it easier to achieve both biodegradability and thermal and mechanical properties.

[0016] The upper limit of the number-average molecular weight of the oligomer is preferably 10,000, 7,500, 5,000, and 3,000, in that order, and the lower limit is preferably 400, 800, and 1,000, in that order. If the number-average molecular weight of the oligomer is within the above range, it exhibits excellent reactivity, and it is possible to achieve both the thermal and mechanical properties and biodegradability of marine biodegradable polymer compounds A and B.

[0017] In the polymer-type polyvalent anion, the lower limit of the number of structural units consisting of oligomers and linking groups is preferably 2, more preferably 3, and the upper limit of structural units is preferably 50, more preferably 20, and even more preferably 10. If the number of structural units is within the above range, it is possible to achieve both biodegradability and thermal and mechanical properties.

[0018] The polymer-type polyvalent anion has an oligomeric structure containing repeating units linked by ester, amide, or ether bonds, and has a first acidic group in its side chain, with one or more further acidic groups located 1 to 30 atoms away from the first acidic group. Any structure is acceptable, but a preferred structure is one composed of repeating oligomers with a number-average molecular weight of 400 to 10,000 and linking groups having two or more acidic groups. Here, a linking group means a structure that is bonded to two or more oligomers, thereby linking the oligomers together. The two or more oligomers constituting such a polymer-type polyvalent anion may be the same oligomer or different oligomers. In addition, components other than oligomers and linking groups may be included for the purpose of adjusting physical properties and biodegradability.

[0019] The content of the oligomer component is preferably 30% by mass or more, more preferably 50% by mass or more, even more preferably 70% by mass or more, and most preferably 80% by mass or more, in the polymer-type polyvalent anion. The content of the linking group component is preferably 70% by mass or less, more preferably 50% by mass or less, even more preferably 30% by mass or less, and most preferably 20% by mass or less, in marine biodegradable polymer compounds A and B. Within the above ranges, the properties derived from the oligomer are exhibited while the linking group provides an improvement in physical properties and biodegradability.

[0020] The polymer-type polyvalent anion may have a linear, branched, cyclic, or a combination thereof structure, but from the viewpoint of biodegradability and physical properties, it is preferably linear or branched, and more preferably linear. A linear polymer-type polyvalent anion can be obtained, for example, by selecting a bifunctional compound from the examples of oligomers described later and a bifunctionally reactive compound from the examples of binders and reacting them. A branched marine biodegradable polymer compound A can be obtained, for example, by selecting at least one of three- or more functional compounds from the examples of oligomers described later and a trifunctionally reactive compound from the examples of binders and reacting them.

[0021] The polymer-type polyvalent anion may have any functional group at its terminus, but from the viewpoint of compound stability and reactivity, it is preferable to have a carboxyl group, a hydroxyl group, or an amino group, more preferably a hydroxyl group or an amino group, and even more preferably a hydroxyl group. Such a polymer-type polyvalent anion can be obtained, for example, by selecting an oligomer having the desired functional group from the examples of oligomers described later and reacting it with an excess amount of the binder, or by selecting a binder from the examples of binders described later that generates the desired functional group upon reaction and reacting it with an even greater excess amount of the oligomer.

[0022] The terminal functional groups may be further chemically modified as needed. For example, the ends may be encapsulated with low-reactivity substituents for purposes such as improving chemical stability, adjusting hydrophobicity and hydrophilicity, or improving heat resistance. The end encapsulant can be arbitrarily selected from monocarboxylic acids, monoacid chlorides, monoesters, monoisocyanates, monoalcohols, monoamines, monoepoxides, etc., depending on the purpose, as long as it is reactive with the terminal substituents. Specific examples include: aliphatic carboxylic acids having 1 to 20 carbon atoms such as formic acid, acetic acid, and stearic acid; acid chlorides of the aliphatic carboxylic acids; aromatic carboxylic acids having 7 to 20 carbon atoms such as benzoic acid, 4-methylbenzoic acid, 4-hexylbenzoic acid, and naphthalenecarboxylic acid; acid chlorides of the aromatic carboxylic acids; aliphatic isocyanates having 1 to 20 carbon atoms such as methyl isocyanate and ocdadodecyl isocyanate; aromatic isocyanates having 7 to 20 carbon atoms such as phenyl isocyanate and 4-butylphenyl isocyanate; Examples include fatty acid alcohols having 1 to 20 carbon atoms such as methanol, ethanol, and stearyl alcohol; aromatic alcohols having 7 to 20 carbon atoms such as benzyl alcohol and 3-phenyl-1-propanol; fatty acid amines having 1 to 20 carbon atoms such as methylamine, ethylamine, and stearylamine; aromatic amines having 7 to 20 carbon atoms such as benzylamine and 4-phenyl-1-butylamine; and epoxides having 2 to 20 carbon atoms such as 1,2-epoxyheptane, 1,2-epoxyhexane, 1,2-epoxydecane, and 1,2-epoxy-5-hexene. From the viewpoint of imparting hydrophobicity, environmental impact, and reactivity, the end-capping agent is preferably aliphatic carboxylic acid having 6 to 20 carbon atoms, acid chlorides of the aliphatic carboxylic acid, acid esters of the aliphatic carboxylic acid, or aliphatic isocyanates having 6 to 20 carbon atoms, and more preferably aliphatic carboxylic acid having 10 to 18 carbon atoms and its acid chlorides.

[0023] From the viewpoint of achieving both thermal and mechanical properties and biodegradability, the oligomer constituting the polymer-type polyvalent anion is preferably bonded by at least one of ester bonds, amide bonds, ether bonds, and urethane bonds in the repeating units constituting the oligomer, more preferably bonded by at least one of ester bonds and amide bonds, even more preferably bonded by only one of either ester bonds or amide bonds, and most preferably bonded by only ester bonds.

[0024] Therefore, from the viewpoint of achieving both thermal and mechanical properties and biodegradability, the oligomer is preferably a polyester, more preferably a polyester with a structure in which a lactone or lactide is ring-opened polymerized, or a polyester with a structure in which a polyhydric alcohol and a polyhydric carboxylic acid are polycondensed, and even more preferably a polyester with a structure in which a polyhydric alcohol and a polyhydric carboxylic acid are polycondensed.

[0025] In the polyester having a structure formed by polycondensation of a polyhydric alcohol and a polyhydric carboxylic acid, the alcohol residue constituting the polyester may be aliphatic, aromatic, or contain both. However, from the viewpoint of thermal and mechanical properties and biodegradability, it is preferable that it be aliphatic only or contain both aliphatic and aromatic residues.

[0026] In the case of a polyester having a polycondensed structure of a polyhydric alcohol and a polyhydric carboxylic acid, if the alcohol residues constituting the polyester include both aliphatic and aromatic residues, from the viewpoint of thermal and mechanical properties and biodegradability, the range of the ratio of aliphatic alcohol residues to aromatic alcohol residues is preferably 10:90 to 95:5, more preferably 20:80 to 90:10, even more preferably 30:70 to 85:15, and most preferably 40:60 to 80:20.

[0027] In the polyester having a structure obtained by polycondensation of the polyhydric alcohol and the polyhydric carboxylic acid, the carboxylic acid residue constituting the polyester may be aliphatic, aromatic, or contain both. However, from the viewpoint of thermal and mechanical properties and biodegradability, it is preferable that it be aliphatic only or contain both aliphatic and aromatic residues, and more preferably aliphatic only.

[0028] In the case of a polyester having a polyhydrate alcohol and a polycarboxylic acid structure formed by polycondensation, if the carboxylic acid residues constituting the polyester include both aliphatic and aromatic residues, from the viewpoint of thermal and mechanical properties and biodegradability, the molar ratio of aliphatic carboxylic acid residues to aromatic carboxylic acid residues is preferably 10:90 to 95:5, more preferably 20:80 to 90:10, even more preferably 30:70 to 85:15, and most preferably 40:60 to 80:20.

[0029] The oligomer may be a commercially available product or a synthesized product. Examples of commercially available products include Kuraray Polyol P-1010, P-2010, P-2011, P-2012, P-2020, P-2050, P-510, P-520, C-590, C-1090, F-510, F-1010 (manufactured by Kuraray Co., Ltd.), Praxel 210B, 220N, 308 (manufactured by Daicel Corporation), polyethylene glycol 1540, polypropylene glycol, diol type 1000, polypropylene glycol, triol type 300 (manufactured by Fujifilm Wako Pure Chemical Industries Ltd.), poly(propylene glycol) bis(2-aminopropyl ether) 400, poly(propylene glycol) bis(2-aminopropyl ether) 2000 (manufactured by Sigma-Aldrich, Inc.), etc. As an example of how oligomers can be synthesized, two or more suitable raw materials can be selected from divalent or higher carboxylic acids, divalent or higher alcohols, divalent or higher amines, divalent or higher isocyanates, lactones, lactams, etc., and obtained by polycondensation or polyaddition reactions. For example, polyester polyols can be obtained by polycondensation of a divalent or higher carboxylic acid and a divalent or higher alcohol, polyamide polyamines by polycondensation of a divalent or higher carboxylic acid and a divalent or higher amine, polyurethane polyols by polyaddition of a divalent or higher isocyanate and a divalent or higher alcohol, ring-opening polymerization type polyesters by ring-opening polymerization of a divalent or higher alcohol and a lactone, and ring-opening polymerization type polyamides by ring-opening polymerization of a divalent or higher amine and a lactam. However, the combination is not limited to these, and three or more raw materials with different functional groups, or two or more different raw materials having the same functional group, may be used simultaneously. The aforementioned divalent or higher carboxylic acids, divalent or higher alcohols, divalent or higher amines, divalent or higher isocyanates, lactones / lactides, and lactams may be derivatized, for example, by acid halides, esters, or halides, in order to enhance reactivity. Known methods can be used for the polycondensation and polyaddition reactions, and metal catalysts or organic catalysts may be used to enhance reactivity as needed.

[0030] Examples of divalent or greater carboxylic acids include oxalic acid, malonic acid, fumaric acid, maleic acid, succinic acid, adipic acid, sebacic acid, 1,2,3-propanetricarboxylic acid, aconitic acid, malic acid, citric acid, phthalic acid, isophthalic acid, terephthalic acid, franzicarboxylic acid, 5-sulfoisophthalic acid, 1,3,5-benzenetricarboxylic acid, 2,6-naphthalenedicarboxylic acid, biphenyldicarboxylic acid, trimetic acid, pyromellitic acid, etc. Succinic acid, adipic acid, sebacic acid, terephthalic acid, franzicarboxylic acid, 5-sulfoisophthalic acid, and 2,6-naphthalenedicarboxylic acid are particularly preferred, with succinic acid, adipic acid, and terephthalic acid being more preferred.

[0031] The aforementioned amines with a valency of 2 or higher include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-butanediamine, 1,5-diaminopentane, 1,6-diaminohexane (hexamethylenediamine), 1,7-diaminoheptane, 1,8-diaminooctane, 1,10-diaminodecane, 1,12-diaminododecane, 3,3-diaminodipropylamine, tris(3-aminopropyl)amine, 3,3'-diaminobenzidine, 1, Examples include 4-cyclohexadiamine, spermine, spermidine, triethylenetetramine, 1,4-phenylenediamine, 1,2-diphenylethylenediamine, and orthotolidine. Ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-butanediamine, hexamethylenediamine, and 1,4-phenylenediamine are particularly preferred, with ethylenediamine, 1,4-butanediamine, and hexamethylenediamine being more preferred.

[0032] Examples of the divalent or higher isocyanates include hexamethylene diisocyanate (HDI), pentamethylene diisocyanate (PDI), isophorone diisocyanate (IPDI), cyclohexane-1,4-diisocyanate, methylenebis(4-cyclohexyl isocyanate), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymeric MDI, xylene diisocyanate, 1,4-phenylene diisocyanate, and others, with HDI, PDI, MDI, and TDI being particularly preferred.

[0033] Examples of the aforementioned lactones and lactides include β-propiolactone, γ-butyrolactone, ε-caprolactone, δ-hexanolactone, mevalonate lactone, 1,3-dioxan-2-one, 1,4-dioxan-2-one, 1,4-dioxan-2,5-dione, γ-heptanolactone, γ-hexanolactone, glycolide, lactide, and 1,6-dioxacyclodecane-2,7-dione, with ε-caprolactone, glycolide, and lactide being particularly preferred.

[0034] Examples of the lactams include β-propiolactam, ε-caprolactam, ω-heptalactam, ω-octalactam, and ω-laurinlactam, with β-propiolactam and ε-caprolactam being particularly preferred.

[0035] The linking group constituting the polymer-type polyvalent anion is bonded to two or more oligomers, and any structure is acceptable as long as two or more oligomers are bonded to each other via the linking group. However, from the viewpoint of thermal and mechanical properties and biodegradability, it is preferable that the linking group has 1, 2, 3, 4, or 5 acidic groups, more preferably 1, 2, or 3 acidic groups, and even more preferably 2 acidic groups.

[0036] When the linking group has two or more acidic groups, from the viewpoint of thermal, mechanical, and biodegradability, each acidic group is preferably located between the nearest adjacent acidic group via 1 to 30 atoms, more preferably via 2 to 20 atoms, and even more preferably via 3 to 10 atoms.

[0037] The linking group preferably does not have repeating units and has a molecular weight of 1000 or less, more preferably 700 or less, and even more preferably 500 or less.

[0038] The structure of the linking group may be linear, branched, or cyclic, but from the viewpoint of reactivity and chemical stability, it is preferable to have a cyclic structure, and more preferably to have an aromatic ring.

[0039] The method for introducing the linking group into the polymer-type polyvalent anion is not particularly limited, but an example is a method using a linking agent that can become a linking group by reacting with an oligomer. Examples of such linking agents include bifunctionally reactive linking agents such as pyromellitic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 4,4'-carbonyldiphthalic anhydride, and bicyclo[2.2.2]octo-7-ene 2,3,5,6-tetracarboxylic dianhydride, bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic dianhydride, 4,4'-biphthalic anhydride, 3,4'-biphthalic anhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, dicyclohexyl-3,4,3',4'-tetracarboxylic dianhydride, ethylene glycol Examples of dihydrotrimellitate dihydroanhydrides and glycol derivatives of acidic dicarboxylic acids such as ethylene glycol bis(5-sulfoisophthalate) and ethylene glycol bis(4-sulfo-6-carboxy-2-naphthoate) are used as linking agents. Trifunctional linking agents include melistic anhydride, trihydrotrimellitate dihydroanhydrides and glycerol tris(5-sulfoisophthalate) and glycerol derivatives and trimethylolpropane derivatives of acidic dicarboxylic acids such as trimethylolpropane tris(4-sulfo-6-carboxy-2-naphthoate). From the viewpoint of thermal and mechanical properties and biodegradability, pyromellitic dianhydride, naphthalene-1,4,5,8-tetracarboxylic acid dianhydride, bicyclo[2.2.2]octo-7-ene-2,3,5,6-tetracarboxylic acid dianhydride and glycerol tris(5-sulfoisophthalate) are preferred, with pyromellitic dianhydride being more preferred.

[0040] One example of a method for synthesizing marine biodegradable polymer compound A is a method of reacting the oligomer with the binder. For example, when using an acid anhydride and a diol oligomer or diamine oligomer, known methods generally used for the reaction of acid anhydrides with alcohols or amines can be used, such as heating and mixing the two. When using a diol oligomer or diamine oligomer and a dicarboxylic acid having an acidic group, known methods generally used for the reaction of alcohols with carboxylic acids or carboxylic acid derivatives, such as direct polycondensation, a method of converting the carboxylic acid portion to an acid halide and heating and mixing it with the oligomer, or a method of converting the carboxylic acid portion to an ester and performing transesterification in the presence of the oligomer using a metal catalyst, or known methods generally used for the reaction of amines with carboxylic acids or carboxylic acid derivatives can be used.

[0041] From the viewpoint of thermal, mechanical, and biodegradable properties, the number-average molecular weight of marine biodegradable polymer compound A is preferably in the order of 800, 1000, 2000, and 4000 for the lower limit, and in the order of 200,000, 100,000, 50,000, and 20,000 for the upper limit.

[0042] The marine biodegradable polymer compound A preferably has a relative biodegradation rate of 40% or more relative to cellulose. In this invention, relative biodegradation rate of cellulose refers to the degree of decomposition of cellulose after 60 days of immersion in seawater. The marine biodegradable polymer compound A is more preferably 50% or more relative to cellulose, even more preferably 60% or more, and most preferably 80% or more. The relative biodegradation rate of cellulose can be measured by ASTM D6691, known marine biodegradation test methods, or BOD modified based on these, and if the sample to be measured is solid, it should be powdered before measurement.

[0043] Marine biodegradable polymer compound B is a compound in which some or all of the protons of the acidic group of marine biodegradable polymer compound A are replaced by monovalent cations other than protons. In other words, marine biodegradable polymer compound B is a salt compound consisting of a polymer-type polyvalent anion, which is a structure in which the protons of the acidic group of marine biodegradable polymer compound A are freed, and a countercation of the anionic group.

[0044] Marine biodegradable polymer compound B can be synthesized, for example, by neutralizing some or all of the acidic groups of marine biodegradable polymer compound A using a base in a known acid-base reaction commonly used for neutralization. Marine biodegradable polymer compound B is preferably obtained in which 1 to 100% of the protons of marine biodegradable polymer compound A are substituted with other monovalent cations. The properties of marine biodegradable polymer compound B can be adjusted by the proton substitution rate, with hydrophilicity improving as the substitution rate increases. For applications requiring hydrophilicity, substitution rates of 50% or more, 70% or more, and 90% or more are preferred in that order, while for applications requiring hydrophobicity, substitution rates of 50% or less, 30% or less, and 10% or less are preferred in that order.

[0045] In the marine biodegradable polymer compound B, the monovalent cation that replaces the proton can be a monovalent metal cation or a monovalent organic cation. Examples of the monovalent metal cation include lithium ions, sodium ions, potassium ions, rubidium ions, cesium ions, francium ions, etc. Examples of the monovalent organic cation include ammonium ions, methylammonium ions, ethylammonium ions, anilinium ions, pyridinium ions, dimethylammonium ions, diethylammonium ions, trimethylammonium ions, triethylammonium ions, etc. Of these, sodium ions, potassium ions, and ammonium ions are preferred from the viewpoint of safety, environmental impact, and ease of handling, and sodium ions and potassium ions are more preferred.

[0046] The marine biodegradable polymer compound B preferably has a relative biodegradation rate of 40% or more relative to cellulose. In this invention, relative biodegradation rate of cellulose refers to the degree of decomposition of cellulose after 60 days of immersion in seawater. The marine biodegradable polymer compound B is more preferably 50% or more relative to cellulose, even more preferably 60% or more, and most preferably 80% or more. The relative biodegradation rate of cellulose can be measured by ASTM D6691, known marine biodegradation test methods, or BOD modified based on these, and if the sample to be measured is solid, it should be powdered before measurement.

[0047] From the viewpoint of thermal and mechanical properties, biodegradability, and reactivity, the number-average molecular weight of marine biodegradable polymer compound B is preferably in the order of 800, 1000, 2000, and 4000 for the lower limit, and in the order of 200,000, 100,000, 50,000, and 20,000 for the upper limit.

[0048] A second aspect of the marine biodegradable polymer compound of the present invention is a structure in which polymer-type polyvalent anions constituting marine biodegradable polymer compound A or B are linked via divalent or higher cations (hereinafter also referred to as marine biodegradable polymer compound C). That is, marine biodegradable polymer compound C has a structure in which polymer-type polyvalent anions derived from marine biodegradable polymer compound A or B are crosslinked by polyvalent cations.

[0049] From the viewpoint of thermal and mechanical properties, biodegradability, and reactivity, the lower limit of the number average molecular weight of the polymer-type polyvalent anion is preferably 800, 1000, 1500, and 2000 in that order, and the upper limit is preferably 100,000, 50,000, 20,000, and 10,000 in that order.

[0050] The aforementioned divalent or higher cation is not particularly limited, but examples include polyvalent ammonium cations obtained from the aforementioned divalent or higher amine, and calcium ions, beryllium ions, magnesium ions, strontium ions, barium ions, zinc ions, aluminum ions, iron ions, copper ions, platinum ions, gold ions, titanium ions, nickel ions, cobalt ions, manganese ions, zirconium ions, ruthenium ions, rhodium ions, palladium ions, scandium ions, gallium ions, indium ions, radium ions, and the like. Among these, polyvalent metal cations such as ethylenediammonium, calcium ions, beryllium ions, magnesium ions, strontium ions, barium ions, zinc ions, and aluminum ions are mentioned. Of these, calcium ions, magnesium ions, and aluminum ions are preferred. The aforementioned divalent or higher cation may be used alone or in combination of two or more types.

[0051] The polyvalent ion equivalents in the aforementioned marine biodegradable polymer compound C are 1 to 100 eq / 10 5 g is preferred, but considering biodegradability in seawater and mechanical properties, 2-80 eq / 10 5 g is more preferable, 10-70 eq / 10 5 g is even more preferable. If the ion equivalent is within the above range, it is preferable because it has good biodegradability and its mechanical properties are not impaired. The ion equivalent is measured by inductively coupled plasma mass spectrometry (ICP-MS) when the ion is a metal, and by liquid chromatography-mass spectrometry (LC-MS) when the ion is an organic cation.

[0052] Marine biodegradable polymer compound C is a compound in which at least two of the polymer-type polyvalent anions are bonded via a metal cation. In marine biodegradable polymer compound C, only one type of polymer-type polyvalent anion may be present, or multiple different types may be present. Marine biodegradable polymer compound C may also simultaneously contain anions derived from anionic compounds other than the polymer-type polyvalent anions (hereinafter also referred to as other anionic compounds). Examples of other anionic compounds include polymer compounds with anionic groups at their terminals and a number average molecular weight of 500 to 10000, carboxylic acid anions with a molecular weight of 1000 or less, amino acid anions with a molecular weight of 1000 or less, amino acid derivative anions with a molecular weight of 1000 or less, and sulfonic acid anions with a molecular weight of 1000 or less.

[0053] Examples of polymer compounds having anionic groups at their termini and a number-average molecular weight of 500 to 10000 include compounds obtained by reacting the oligomer or its derivative with divalent carboxylic acid anhydrides such as succinic anhydride, maleic anhydride, phthalic anhydride, and naphthic anhydride, followed by neutralization, and compounds obtained by reacting the oligomer or its derivative with an SO3 Lewis base complex, followed by neutralization. Preferably, the oligomer is reacted with succinic anhydride, maleic anhydride, or phthalic anhydride, followed by neutralization, and more preferably, the oligomer is reacted with succinic anhydride or maleic anhydride, followed by neutralization.

[0054] The carboxylic acid anions include 1,5-naphthalenedisulfonic acid, ethanedisulfonic acid, monoethyl phosphate, malic acid, aspartic acid, glutamic acid, succinic acid, adipic acid, sebacic acid, terephthalic acid, isophthalic acid, caproic acid, enanthic acid, caprylic acid, octyl acid, pelargonic acid, capric acid, undecylenic acid, lauric acid, myristic acid, pentadecyl acid, palmitic acid, palmitoleic acid, margaric acid, stearic acid, isostearic acid, oleic acid Anions such as licinic acid, vaccenic acid, ricinoleic acid, linoleic acid, linolenic acid, eleostearic acid, oxystearic acid, arachidic acid, meadic acid, arachidonic acid, eicosapentaenoic acid, behenic acid, docosahexaenoic acid, lignoceric acid, nervonic acid, cerotic acid, montanic acid, melissic acid, coconut oil fatty acid, and palm oil fatty acid are examples, with lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, and linoleic acid anions being particularly preferred.

[0055] The aforementioned amino acid anions or amino acid derivative anions include anions of amino acids such as alanine, leucine, arginine, lysine, asparagine, methionine, aspartic acid, phenylalanine, cysteine, proline, glutamine, serine, glutamic acid, threonine, glycine, tryptophan, histidine, tyrosine, and isoleucine, as well as sarcosine derivatives (caproyl sarcosine, lauroyl sarcosine, myristoyl sarcosine, palmitoyl sarcosine, coconut oil fatty acid sarcosine, etc.) and glutamine. Acid derivatives (caproyl glutamic acid, lauroyl glutamic acid, myristoyl glutamic acid, palmitoyl glutamic acid, stearoyl glutamic acid, coconut oil fatty acid acyl glutamic acid, cocoyl glutamic acid, acyl glutamic acid, dilauroyl glutamic acid, etc.), glycine derivatives (lauroyl glycine, myristoyl glycine, palmitoyl glycine, palmitoyl methylglycine, coconut oil fatty acid acyl glycine, cocoyl glycine, etc.), alanine derivatives (lauryl methylalanine, myristoyl methylalanine) Lysine derivatives (such as cocoyl alanine, coconut oil fatty acid methyl alanine), lysine derivatives (such as lauroyl lysine, myristoyl lysine, palmitoyl lysine, stearoyl lysine, oleyl lysine, acylated lysine, etc.), aspartic acid derivatives (such as lauroyl aspartic acid, myristoyl aspartic acid, palmitoyl aspartic acid, stearoyl aspartic acid, etc.), taurine derivatives (such as lauroyl taurine, lauroyl methyl taurine, myristoyl taurine, myristoyl methyl taurine, palmitoyl Examples include anions of amino acid derivatives having hydrocarbon groups, such as toylmethyltaurine, stearoyltaurine, stearoylmethyltaurine, etc., and proline derivatives (lauroylproline, myristoylproline, palmitoylproline, etc.). Anions of caproylsarcosine, lauroylsarcosine, myristoylsarcosine, palmitoylsarcosine, caproylglutamic acid, lauroylglutamic acid, myristoylglutamic acid, palmitoylglutamic acid, and stearoylglutamic acid are particularly preferred.

[0056] Examples of the sulfonic acid anions include alkyl sulfonic acids (lauryl sulfonic acid, myristyl sulfonic acid, cetyl sulfonic acid, stearyl sulfonic acid, oleyl sulfonic acid, etc.), dodecylbenzene sulfonic acid, dialkyl succinate sulfonic acid, monoalkyl succinate sulfonic acid, naphthalene sulfonic acid, olefin sulfonic acid, alkyl isethionic acid (lauroyl isethionic acid, myristoyl isethionic acid, palmitoyl isethionic acid, stearoyl isethionic acid, etc.), and dialkyl sulfosuccinates (dihexyl sulfosuccinate, dioctyl sulfosuccinate, didecyl sulfosuccinate, diisobutyl sulfosuccinate, etc.), with lauryl sulfonic acid, myristyl sulfonic acid, cetyl sulfonic acid, and stearyl sulfonic acid anions being particularly preferred.

[0057] When marine biodegradable polymer compound C is mixed with other resins, it is preferable that it has a softening point or melting point suitable for the melting temperature of those resins. The polymer compound is solid at room temperature, and more specifically, the lower limit of the softening point or melting point is preferably 40°C, 50°C, and 60°C in that order, and the upper limit is preferably 250°C, 180°C, 160°C, and 140°C in that order. If the other resin is a biodegradable resin, it is preferable that the softening point or melting point is within the range of 40 to 200°C, more preferably 50 to 160°C, and even more preferably 60 to 140°C.

[0058] The marine biodegradable polymer compound C preferably has a relative biodegradation rate of 40% or more relative to cellulose. In this invention, relative biodegradation rate of cellulose refers to the degree of decomposition of cellulose after 60 days of immersion in seawater. The marine biodegradable polymer compound C is more preferably 50% or more relative to cellulose, even more preferably 60% or more, and most preferably 80% or more. The relative biodegradation rate of cellulose can be measured by ASTM D6691, known marine biodegradation test methods, or BOD modified based on these, and if the sample to be measured is solid, it should be powdered before measurement.

[0059] Marine biodegradable polymer compound C can be produced by a method that includes a step of crosslinking the polyester-type polyvalent anion contained in marine biodegradable polymer compound A or B using a polyvalent salt.

[0060] The aforementioned crosslinking treatment methods include a method in which a powder or solution of polyvalent salt is added dropwise to a medium in which marine biodegradable polymer compound B is dissolved or dispersed, and precipitates or settles while performing a bonding treatment; a method in which a powder or solution of polyvalent salt is added dropwise to a molten solution of marine biodegradable polymer compound B, and a bonding treatment is performed; and a method in which a solution in which marine biodegradable polymer compound B is dissolved is added dropwise to a solution in which a powder of polyvalent salt or a polyvalent metal salt is dissolved, and precipitates or settles while performing a bonding treatment.

[0061] As a preferred example, a solution is prepared by dissolving or dispersing marine biodegradable polymer compound B in water, an organic solvent, or a mixture thereof, or by heating marine biodegradable polymer compound B to dissolve or disperse it. At this time, heating may be done as necessary to improve solubility and dispersibility, or to reduce the viscosity of the molten liquid. Next, a solution containing a divalent or higher salt is added to the obtained solution, dispersion, or molten liquid and stirred. Alternatively, a solution, dispersion, or molten liquid in which marine biodegradable polymer compound B is dissolved in a solution containing a divalent or higher salt may be added and stirred.

[0062] Examples of the polyvalent salts include organic salts such as the salts of the polyvalent amines, and metallic salts such as calcium salts, strontium salts, magnesium salts, barium salts, radium salts, lead salts, zinc salts, nickel salts, iron salts, copper salts, cadmium salts, cobalt salts, manganese salts, aluminum salts, gallium salts, indium salts, and thallium salts. However, from the standpoint of environmental impact, safety, and versatility, ethylenediammonium salts, calcium salts, magnesium salts, and aluminum salts are preferred, and calcium salts and magnesium salts are more preferred when considering the environment of seawater. Specific examples of the polyvalent salts include ethylenediamine hydrochloride, ethylenediamine sulfate, calcium chloride, calcium sulfate, calcium carbonate, calcium hydroxide, calcium oxide, magnesium chloride, magnesium sulfate, magnesium carbonate, magnesium hydroxide, magnesium oxide, aluminum sulfate, sodium aluminum sulfate (sodium alum), potassium aluminum sulfate (potassium alum), etc. However, from the viewpoint of solubility in water, ease of handling, and cost, ethylenediamine hydrochloride, calcium chloride, magnesium chloride, and aluminum sulfate are preferred, and calcium chloride and magnesium chloride are more preferred.

[0063] Furthermore, neutralization and bonding via a cation of two or more valent values ​​can be achieved simultaneously by neutralizing the acidic group of marine biodegradable polymer compound A with a base of two or more valent values.

[0064] A preferred example of this method is to prepare a solution by dissolving or dispersing marine biodegradable polymer compound A in water, an organic solvent, or a mixture thereof, or a molten solution by heating and dissolving marine biodegradable polymer compound A. At this time, heating may be done as necessary to improve solubility or to reduce the viscosity of the molten solution. Next, a solution of a divalent or higher base is added to the obtained solution, dispersion, or molten solution and stirred. Alternatively, a solution, dispersion, or molten solution of marine biodegradable polymer compound A dissolved in a solution of a divalent or higher base may be added and stirred.

[0065] Examples of the divalent or higher bases include the polyvalent amines as organic bases, and magnesium hydride, strontium hydride, calcium hydride, barium hydride, magnesium methoxide, calcium methoxide, strontium methoxide, barium methoxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium oxide, strontium oxide, calcium oxide, barium oxide, magnesium carbonate, strontium carbonate, calcium carbonate, barium carbonate, magnesium bicarbonate, strontium bicarbonate, calcium bicarbonate, and barium bicarbonate. However, ethylenediamine, calcium hydride, calcium methoxide, calcium hydroxide, and barium hydroxide are preferred in terms of solubility in water, reactivity, cost, etc., and calcium hydroxide is more preferred.

[0066] The concentration of the polyvalent salt in the solution containing the polyvalent salt, or the concentration of the base in the solution containing a base of 2 or more valents, is preferably 1 to 40% by mass, and more preferably 10 to 30% by mass. The solvent of the solution is preferably a lower alcohol solvent such as water, methanol, ethanol, 1-propanol, 2-propanol, amphiphilic solvents such as acetone, acetonitrile, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, or a mixture thereof. However, a mixture of other organic solvents is also acceptable as long as the salt can be dissolved to the desired concentration without dissolving the particles.

[0067] Furthermore, if the polyvalent salt or divalent or more base is highly reactive and reacts even in a solid state, it may be used in powder form without a medium, or dispersed in a small amount of a medium.

[0068] In this way, the polymer-type polyvalent anions contained in marine biodegradable polymer compound A or B can be bonded via divalent or higher cations, and the target marine biodegradable polymer compound C, which has gradually become insoluble, is obtained as precipitate, sediment, or bulk. The processing time is preferably 0.5 to 24 hours, and more preferably 1 to 12 hours.

[0069] In this case, for the purpose of controlling the particle size and shape (such as spherical) of the precipitate or sediment, a surfactant or polymer stabilizer may be dissolved in at least one of a solution containing marine biodegradable polymer compound A or B, and a solution containing a divalent or polyvalent base or polyvalent salt.

[0070] Heating may be performed when precipitating or precipitation the target marine biodegradable polymer compound C. Heating may be performed when mixing a solution containing a dissolved or dispersed marine biodegradable polymer compound A or B, or a molten marine biodegradable polymer compound A or B, with a solution containing a polyvalent salt or a base of two or more progenitors, or when stirring after mixing, or both. The heating temperature is preferably 15 to 150°C, more preferably 20 to 100°C, and more preferably 40 to 80°C.

[0071] After processing, marine biodegradable polyester C can be obtained by washing the resin as needed. Washing can be carried out by conventional methods, such as removing the solvent after bonding and adding water, followed by centrifugation or decantation.

[0072] After washing, marine biodegradable polyester C can be obtained by drying as needed. Drying can be carried out by conventional methods, such as spray drying, vacuum drying, or freeze-drying. The drying process may also involve stirring or heating, and if heating is used, a temperature of 30 to 200°C is preferred, 40 to 190°C is more preferred, and 60 to 180°C is even more preferred.

[0073] After drying, heating may be performed to improve fluidity when extracting marine biodegradable polyester C, in which case a temperature of 20 to 180°C is preferred, 30 to 160°C is more preferred, and 40 to 140°C is even more preferred.

[0074] Furthermore, the obtained marine biodegradable polyester C may be subjected to surface treatment or pulverization to adjust its particle size using known equipment, if necessary.

[0075] The marine biodegradable polymer compound C may have at least one of its ends that are not bonded to the polymer-type polyvalent anions via a divalent cation sealed with a sealing segment group.

[0076] By selecting the appropriate sealing segment group, multiple effects can be incorporated in single materials and composite materials (marine biodegradable compositions) using this material, such as adjustment of melt temperature and melt viscosity, adjustment of crystallinity, adjustment of microbial adhesion and biodegradability, adjustment of physical properties such as resin tensile strength, flexural strength, and elasticity, improvement of compatibility with resins, adjustment of hydrophobicity, adjustment of water repellency, adjustment of adhesion, and adjustment of plasticity. This allows for improvements in both the biodegradability and physical properties of marine biodegradable compositions. Since the organic anion that forms the sealing segment is desirable to have a structure that is biodegradable in the ocean, it is desirable to select a sealing segment group with a molecular weight of 5000 or less that is biodegradable in the ocean. For example, when prioritizing the biodegradation rate in the ocean and maintaining average physical properties, a molecular weight of 2500 or less is preferred, and a molecular weight of 1000 or less is more preferred.

[0077] Specifically, the sealing segment group is preferably one having a monovalent hydrocarbon group with 3 or more carbon atoms, more preferably one having a monovalent hydrocarbon group with 6 or more carbon atoms, even more preferably one having a monovalent hydrocarbon group with 10 or more carbon atoms, and most preferably one having a monovalent hydrocarbon group with 12 or more carbon atoms. The upper limit of the number of carbon atoms in the monovalent hydrocarbon group is not particularly limited, but is preferably 30 or less, more preferably 25 or less, and even more preferably 20 or less.

[0078] The sealing segment group is preferably a monovalent organic anion selected from a carboxylic acid anion having 3 or more C3 monovalent hydrocarbon groups, a sulfonic acid anion having 3 or more C3 monovalent hydrocarbon groups, a sulfate ester anion having 3 or more C3 monovalent hydrocarbon groups, and a phosphate ester anion having 3 or more C3 monovalent hydrocarbon groups. Of these, it is preferably a monovalent organic anion derived from a carboxylic acid having 3 or more C3 monovalent hydrocarbon groups, and more preferably a monovalent organic anion derived from a fatty acid having 3 or more C3 monovalent hydrocarbon groups or an amino acid derivative having 3 or more C3 monovalent hydrocarbon groups.

[0079] End encapsulation can be performed using at least one end encapsulant selected from carboxylic acids having three or more C3 or more monovalent hydrocarbon groups, salts of the carboxylic acid, sulfonic acids having three or more C3 or more monovalent hydrocarbon groups, salts of the sulfonic acid, sulfate esters having three or more C3 or more monovalent hydrocarbon groups, salts of the sulfate esters, phosphate esters having three or more C3 or more monovalent hydrocarbon groups, and salts of the phosphate esters. End encapsulation can be performed by adding the end encapsulant to a solution containing polymer compound A or B, and then binding with polyvalent metal ions.

[0080] As the end-capturing agent, acid compounds or salt compounds described in paragraphs

[0029] to

[0044] of Japanese Patent Application Publication No. 2021-191810 are preferred.

[0081] [Marine biodegradable composition] The marine biodegradable composition of the present invention comprises at least one selected from the marine biodegradable polymer compounds A, B, and C.

[0082] The marine biodegradable polymer compound may be used as the main raw material, or it may be used as an additive in combination with other resins. The other resins are not particularly limited, but are preferably biodegradable resins. In this case, the composite resin will be a composition that promotes biodegradation in the ocean. Furthermore, in order to adjust the physical properties and handling characteristics of the composition, multiple types of resins may be used in combination as the other resins.

[0083] Other resins include polyethylene, polyester, polypropylene, polyethylene terephthalate, polystyrene, polyurethane, epoxy resin, chlorinated polyethylene resin, chlorinated polypropylene resin, modified nylon resin, phenolic resin, silicone resin, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, styrene-maleic acid resin, styrene-butadiene resin, butadiene resin, acrylonitrile-butadiene resin, poly(meth)acrylonitrile resin, (meth)acrylamide resin, bioPET, biopolyamide, biopolycarbonate, biopolyurethane, polyvinyl alcohol, polybutylene adipate / terephthalate, polyethylene terephthalate succinate, biopolybutylene succinate, polylactic acid blend, starch blend polyester resin, polybutylene terephthalate succinate, polylactic acid, polyhydroxyalkanoic acid, etc. However, considering the reduction of environmental impact and the effect of promoting marine biodegradability, resins with high biodegradability are particularly preferred.

[0084] Furthermore, the biodegradable resins include polycaprolactone, poly(caprolactone / butylene succinate), polybutylene succinate (PBS), poly(butylene succinate / adipate) (PBSA), poly(butylene adipate / terephthalate) (PBAT), poly(butylene succinate / carbonate), polyethylene terephthalate copolymer, poly(ethylene terephthalate / succinate), poly(tetramethylene adipate / terephthalate), polyethylene succinate, polyvinyl alcohol, polyglycolic acid, glycolic acid / caprolactone copolymer, glycolic acid / trimethylene carbonate copolymer, etc., which are resins derived from petroleum; (polylactic acid / polybutylene succinate-based) block copolymer, (polylactic acid / polycaprolactone) copolymer, (polylactic acid / polyether) copolymer Examples include resins whose raw materials are partially derived from biomass, such as polylactic acid blend PBAT, lactic acid / glycolic acid copolymer, biopolybutylene succinate, poly(butylene succinate / adipate), starch blend polyester resin, and poly(butylene terephthalate succinate); resins whose raw materials are 100% derived from biomass, such as polyhydroxyalkanoates like polyhydroxybutyrate, polyhydroxyvaleric acid, polyhydroxycaprylic acid, poly(hydroxybutyrate / hydroxyhexanoate) (PHBH), poly(3-hydroxybutyrate / 4-hydroxybutyrate) (P3HB4HB), and poly(hydroxybutyrate / hydroxyvaleric acid) (PHBV), and polylactic acid (PLA); and resins derived from natural polymers such as cellulose, cellulose acetate, cellulose ester resin, starch, esterified starch, and chitosan. These may be used individually or in combination of two or more.

[0085] Of these, it is preferable to combine a biodegradable resin, selected from resins that are biodegradable in soil or compost but have poor biodegradability in the ocean, such as polycaprolactone, PBS, PBSA, PBAT, poly(tetramethylene adipate / terephthalate), poly(butylene succinate / carbonate), PHBH, PHBV and other polyhydroxyalkanoates, PLA, cellulose, starch, chitosan and other resins derived from natural polymers, with the marine biodegradable polymer compound. Among these, PBSA, PBS, PBAT, PLA and starch-derived resins are particularly preferred as the biodegradable resin.

[0086] Furthermore, considering the reduction of environmental impact, the raw materials for the resin to be combined are preferably 20% or more biomass-derived, more preferably 50% or more biomass-derived, and most preferably 100% biomass-derived.

[0087] The marine biodegradable composition of the present invention may contain a solvent. The solvent may dissolve the resin matrix while leaving the marine biodegradable polymer compound as particles, or it may dissolve both the resin and the marine biodegradable polymer compound. By appropriately adjusting these, the composition can be used as a molded product formed into a film by casting, or as a paint, ink, surface treatment agent, etc. Preferred solvents include, for example, water, formic acid, hexane, heptane, acetonitrile, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dimethyl sulfone, acetone, methyl ethyl ketone, diethyl ketone, acetophenone, dimethyl ether, dipropyl ether, tetrahydrofuran, chloroform, methylene chloride (dichloromethane), trichloroethylene, dichloroethylene, tetrachloroethane, chlorobenzene, methanol, ethanol, n-propanol, isopropanol, butanol, pentanol, hexafluoroisopropanol, methyl glycol, methyl triglyceride, hexyl glycol, phenyl glycol, ethylene glycol, propylene glycol, phenol, cresol, polyethylene glycol, benzene, toluene, and xylene. These may be used individually or in combination of two or more.

[0088] When a solvent is used, the total concentration of the resin and marine biodegradable polymer compound in the composition is preferably 0.5 to 90% by mass, more preferably 1 to 80% by mass, even more preferably 5 to 60% by mass, and most preferably 10 to 50% by mass. Furthermore, the ratio of the marine biodegradable polymer compound to the resin is preferably 99:1 to 10:90 by mass ratio, more preferably 97:3 to 40:60, even more preferably 95:5 to 50:50, and most preferably 90:10 to 60:40.

[0089] The lower limit of the softening point of the composition is preferably 50°C, 60°C, and 70°C, in that order, and the upper limit is preferably 250°C, 200°C, and 180°C, in that order. Preferably, the softening point is in the range of 50 to 250°C, more preferably 60 to 200°C, and even more preferably 70 to 180°C.

[0090] Furthermore, the marine biodegradable composition of the present invention does not need to contain a solvent. In this case, the resin may be heated and melted, and a non-melting marine biodegradable polymer compound may be added and mixed thereto, or the resin and the marine biodegradable polymer compound may be melted together and mixed.

[0091] In the marine biodegradable composition of the present invention, the content of the marine biodegradable polymer compound is preferably 1 to 60% by mass, more preferably 3 to 50% by mass, even more preferably 5 to 45% by mass, still more preferably 7 to 40% by mass, and most preferably 10 to 35% by mass. On the other hand, the resin content is preferably 40 to 99% by mass, more preferably 50 to 97% by mass, even more preferably 55 to 95% by mass, still more preferably 60 to 93% by mass, and most preferably 65 to 90% by mass. By including the marine biodegradable polymer compound within the above range, the marine biodegradable composition of the present invention can be used as a marine biodegradation accelerator that promotes biodegradation in seawater while maintaining the physical properties of the biodegradable resin. The marine biodegradable polymer compound may be used alone or in combination of two or more types.

[0092] The tensile strength of the test specimen obtained from the composition is preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more, compared to a blank resin test specimen that does not contain the marine biodegradable polymer compound of the present invention, when the content of the marine biodegradable polymer compound in the composition is 10% by mass. Furthermore, when the content of the marine biodegradable polymer compound in the composition is 30% by mass, the tensile strength is preferably 65% ​​or more, more preferably 70% or more, and even more preferably 80% or more.

[0093] The marine biodegradable composition of the present invention may optionally contain additives such as antioxidants, mold release agents, release agents, surface modifiers, hydrophobic agents, water-repellent agents, hydrophilic agents, dyes and pigments, colorants, heat stabilizers, light stabilizers, weather resistance improvers, antistatic agents, antifogging agents, lubricants, antiblocking agents, hardening agents, softening agents, compatibilizers, flame retardants, flow improvers, plasticizers, dispersants, antibacterial agents, fillers, and metal deactivators. The content of these additives is not particularly limited as long as it does not impair the effects of the present invention, but is preferably about 0.1 to 50 parts by mass per 100 parts by mass of resin.

[0094] If the marine biodegradable composition contains a solvent, it can be prepared, for example, by adding the resin, the marine biodegradable polymer compound, and the additives as needed to the solvent simultaneously or in any order and mixing them. If the marine biodegradable composition does not contain a solvent, for example, the resin may be melted, and the marine biodegradable polymer compound and the additives as needed may be added simultaneously or in any order and mixed; or the resin and the marine biodegradable polymer compound may be heated to melt them together and mixed, and the additives as needed may be added and mixed.

[0095] [Molded body] By molding using the aforementioned marine biodegradable composition, a molded article can be obtained in which the marine biodegradable polymer compound is dispersed or dissolved in the resin. If the composition contains a solvent, the composition can be used as is for molding; if the composition does not contain a solvent, the resin in the composition, or the resin and marine biodegradable polymer compound, can be melted by heat before molding.

[0096] Examples of the shape of the molded article include film-like, fibrous, plate-like, foamed molded article-like, and other shapes depending on the application. The molding method is not particularly limited, and various conventionally known molding methods can be used. Specific examples include blow molding, injection molding, extrusion molding, compression molding, melt extrusion molding, solution casting molding, and calendering.

[0097] [Application] The marine biodegradable polymer compound and marine biodegradable composition of the present invention can be used as raw materials for plastic molded products and as various additives for molded products such as liquids, coating films, films, plate materials, paper, etc. When used as a raw material for plastic molded products, it can be used as raw materials for general-purpose applications such as films, packaging, containers, trays, laminates, adhesives, coating materials, medical, fibers for clothing, shoes, belts, tires, tubes, shock absorbers, fishing lines, fishing nets, etc. and materials for marine applications, etc., and can be preferably used as raw materials for materials for marine applications, etc. Further, when used as an additive, for example, light scattering agents, optical filter materials, colorants, cosmetics, absorbers, adsorbents, inks, adhesives, electromagnetic wave shielding materials, fluorescent sensors, biological markers, recording materials, recording elements, polarizing materials, drug carriers for drug delivery systems (DDS), biosensors, DNA chips, test drugs, fired porous formed products, antiblocking agents, screen printing, offset printing, process printing, gravure printing, tampo printing, coaters, printing ink additives used in inkjet, etc., writing implement ink additives for marking pens, ballpoint pens, fountain pens, brush pens, magic pens, etc., stationery additives such as crayons, paints, erasers, etc., paint additives used in brush coating, spray coating, electrostatic coating, electrocoating, flow coating, roller coating, dip coating, etc., and can be widely used as additives for paints used in marine applications such as hull paints, etc.

Examples

[0098] Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following Examples and Comparative Examples, the metal ion equivalent was measured by emission analysis using ICP-MS (ICPE-9820 manufactured by Shimadzu Corporation) after heating and decomposing the target substance with nitric acid or aqua regia. The organic cation equivalent was measured using LC-MS / MS (Triple Quad 3500 manufactured by AB SCIEX) by immersing the target substance in a solution containing brine or a chelating agent to depolymerize it. The number average molecular weight and the number of anionic groups were measured using a nuclear magnetic resonance apparatus (JNM-ECZ400S manufactured by JEOL Ltd.), 1It was calculated from the integrated value of the peaks in 1H-NMR.

[0099] [1] Synthesis of marine biodegradable polymer compound A

[0100] [Example 1-1] Synthesis of marine biodegradable polymer compound A-1 100 g of polyester diol (Kuraray Polyol P-1010, manufactured by Kuraray Co., Ltd.), 16.4 g of pyromellitic dianhydride, and 11.6 g of acetonitrile were charged into a 500 mL reaction vessel and stirred at 130 °C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-1. Marine biodegradable polymer compound A-1 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 4700 by 1H-NMR measurement.

[0101] [Examples 1-2] Synthesis of marine biodegradable polymer compound A-2 In a 500 mL reaction vessel, 50.0 g of dimethyl adipate, 23.9 g of dimethyl terephthalate, 45.5 g of 1,4-butanediol, and 0.47 g of titanium tetraisopropoxide were charged and stirred at 160°C under a nitrogen atmosphere for 6 hours to obtain oligomer A-2. In a 500 mL reaction vessel, 90.0 g of oligomer A-2, 15.8 g of naphthalene-1,4,5,8-tetracarboxylic dianhydride, and 10.6 g of acetonitrile were charged and stirred at 130°C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-2. Marine biodegradable polymer compound A-2 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 5400 by 1H-NMR measurement.

[0102] [Examples 1-3] Synthesis of marine biodegradable polymer compound A-3 In a 500 mL reaction vessel, 15.0 g of dimethyl adipate, 50.3 g of dimethyl succinate, 45.8 g of 1,4-butanediol, and 0.49 g of titanium tetraisopropoxide were charged and stirred at 160°C under a nitrogen atmosphere for 6 hours to obtain oligomer A-3. In a 500 mL reaction vessel, 90.0 g of oligomer A-3, 15.2 g of pyromellitic dianhydride, and 10.5 g of acetonitrile were charged and stirred at 130°C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-3. Marine biodegradable polymer compound A-3 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 5700 by 1H-NMR measurement.

[0103] [Examples 1-4] Synthesis of marine biodegradable polymer compound A-4 In a 500 mL reaction vessel, 100 g of polyethylene glycol 1540 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 12.4 g of bicyclo[2.2.2]octo-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, and 11.2 g of acetonitrile were charged and stirred at 130 °C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-4. Marine biodegradable polymer compound A-4 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 6700 by 1H-NMR measurement.

[0104] [Examples 1-5] Synthesis of marine biodegradable polymer compound A-5 In a 500 mL reaction vessel, 100 g of poly(propylene glycol) bis(2-aminopropyl ether) 400 (manufactured by Sigma-Aldrich), 43.6 g of pyromellitic dianhydride, and 14.4 g of acetonitrile were charged and stirred at 130 °C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-5. Marine biodegradable polymer compound A-5 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1The number-average molecular weight was confirmed to be 2900 by 1H-NMR measurement.

[0105] [Examples 1-6] Synthesis of marine biodegradable polymer compound A-6 In a 500 mL reaction vessel, 40.0 g of dimethyl adipate, 44.6 g of dimethyl terephthalate, 51.7 g of 1,4-butanediol, and 0.52 g of titanium tetraisopropoxide were charged and stirred at 160°C under a nitrogen atmosphere for 6 hours to obtain oligomer A-6. In a 500 mL reaction vessel, 50 g of oligomer A-6, 50 g of polyester diol (Kuraray Polyol P-1010, manufactured by Kuraray Co., Ltd.), 15.6 g of pyromellitic dianhydride, and 11.6 g of acetonitrile were charged and stirred at 130°C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-6. Marine biodegradable polymer compound A-6 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 4000 by 1H-NMR measurement.

[0106] [Examples 1-7] Synthesis of marine biodegradable polymer compound A-7 In a 500 mL reaction vessel, 50.0 g of dimethyl adipate, 37.2 g of dimethyl terephthalate, 45.3 g of 1,4-butanediol, and 0.54 g of titanium tetraisopropoxide were charged and stirred at 160°C under a nitrogen atmosphere for 6 hours to obtain oligomer A-7. In a 500 mL reaction vessel, 100 g of oligomer A-7, 6.50 g of pyromellitic dianhydride, and 10.7 g of acetonitrile were charged and stirred at 130°C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-7. Marine biodegradable polymer compound A-7 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 10700 by 1H-NMR measurement.

[0107] [Examples 1-8] Synthesis of marine biodegradable polymer compound A-8 72.6 g of sodium 5-sulfoisophthalate, 8.00 g of ethylene glycol, and 0.81 g of concentrated sulfuric acid were added to a 500 mL reaction vessel and stirred at 250 °C for 4 hours under a nitrogen atmosphere. After cooling to room temperature, the mixture was washed with a 50% by mass aqueous solution of 2-propanol and vacuum-dried to obtain L-1. Next, 60.0g of polyester diol (Kuraray Polyol P-510, manufactured by Kuraray Co., Ltd.), 56.0g of L-1, 13.2g of 4-dimethylaminopyridine, and 24.9g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride were added to a 500mL reaction vessel. 11.6 g of dichloromethane was added and stirred under a nitrogen atmosphere at 25°C for 24 hours. By removing the by-products by filtration, marine biodegradable polymer compound A-8 was obtained. Marine biodegradable polymer compound A-8 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 9300 by 1H-NMR measurement.

[0108] [Examples 1-9] Synthesis of marine biodegradable polymer compound A-9 100 g of polyester diol (Kuraray Polyol F-1010, manufactured by Kuraray Co., Ltd.), 17.4 g of pyromellitic dianhydride, and 11.7 g of acetonitrile were charged into a 500 mL reaction vessel and stirred at 130 °C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-9. Marine biodegradable polymer compound A-9 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 4700 by 1H-NMR measurement.

[0109] [Examples 1-10] Synthesis of marine biodegradable polymer compound A-10 In a 500 mL reaction vessel, 100 g of polyester diol (Kuraray Polyol P-2011, manufactured by Kuraray Co., Ltd.), 10.4 g of pyromellitic dianhydride, and 11.0 g of acetonitrile were charged and stirred at 130 °C under a nitrogen atmosphere for 3 hours to obtain marine biodegradable polymer compound A-10. Marine biodegradable polymer compound A-10 consists of a repeating structure of oligomers and linking groups having two or more acidic groups. 1 The number-average molecular weight was confirmed to be 49,700 by 1H-NMR measurement. A 300 μm thick film was produced by press-molding the marine biodegradable polymer compound A-10 at 120°C.

[0110] [Comparative Example 1-1] Synthesis of Polymer Compound X-1 100 g of polyester diol (Kuraray Polyol P-1010, manufactured by Kuraray Co., Ltd.), 20.5 g of succinic anhydride, and 12.1 g of acetonitrile were charged into a 500 mL reaction vessel and stirred at 130 °C for 3 hours under a nitrogen atmosphere to obtain marine biodegradable polymer compound X-1. Marine biodegradable polymer compound X-1 is linear, 1 The number-average molecular weight was confirmed to be 1200 by 1H-NMR measurement.

[0111] [Comparative Example 1-2] Polymer Compound X-2 A solid resin obtained by heating 100g of a 50% by mass polyacrylic acid aqueous solution (Mw~5000) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to evaporate the water and drying it under reduced pressure at 120°C for 2 hours was used as comparative polymer compound X-2.

[0112] Table 1 below shows the marine biodegradable polymer compounds A-1 to A-10 and X-1 to X-2 together.

[0113] [Table 1]

[0114] [2] Synthesis of marine biodegradable polymer compound B

[0115] [Example 2-1] Synthesis of marine biodegradable polymer compound B-1 50.0 g of marine biodegradable polymer compound A-1 was added to a 500 mL reaction vessel and melted at 120 °C. Subsequently, 10.7 g of 30% by mass sodium hydroxide aqueous solution and 39.3 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-1 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-1 were replaced with sodium ions.

[0116] [Example 2-2] Synthesis of marine biodegradable polymer compound B-2 50.0 g of marine biodegradable polymer compound A-2 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 13.0 g of 30% by mass potassium hydroxide aqueous solution and 37.0 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-2 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-2 were replaced with potassium ions.

[0117] [Examples 2-3] Synthesis of marine biodegradable polymer compound B-3 50.0 g of marine biodegradable polymer compound A-3 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 6.20 g of a 30% by mass potassium hydroxide aqueous solution and 43.8 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-3 as a 50% by mass aqueous dispersion, in which 50% of the protons of the acidic groups of marine biodegradable polymer compound A-3 were replaced with potassium ions.

[0118] [Examples 2-4] Synthesis of marine biodegradable polymer compound B-4 50.0 g of marine biodegradable polymer compound A-4 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 10.4 g of 30% by mass potassium hydroxide aqueous solution and 39.6 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-4 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-4 were replaced with potassium ions.

[0119] [Examples 2-5] Synthesis of marine biodegradable polymer compound B-5 50.0 g of marine biodegradable polymer compound A-5 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 18.2 g of 30% by mass potassium hydroxide aqueous solution and 31.8 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-5 as a 50% by mass aqueous dispersion, in which 70% of the protons of the acidic groups of marine biodegradable polymer compound A-5 were replaced with potassium ions.

[0120] [Examples 2-6] Synthesis of marine biodegradable polymer compound B-6 50.0 g of marine biodegradable polymer compound A-6 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 14.4 g of 30% by mass potassium hydroxide aqueous solution and 35.6 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-6 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-6 were replaced with potassium ions.

[0121] [Examples 2-7] Synthesis of marine biodegradable polymer compound B-7 50.0 g of marine biodegradable polymer compound A-7 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 0.51 g of 28% by mass aqueous ammonia and 49.9 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-7 as a 50% by mass aqueous dispersion, in which 30% of the protons in the acidic groups of marine biodegradable polymer compound A-7 were replaced with ammonium ions. Subsequently, 30.0 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-7 was taken out, heated to evaporate the water, and dried under reduced pressure at 120°C for 2 hours to obtain marine biodegradable polymer compound B-7 as a solid resin.

[0122] [Examples 2-8] Synthesis of marine biodegradable polymer compound B-8 50.0 g of marine biodegradable polymer compound A-8 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 22.5 g of 30% potassium hydroxide aqueous solution and 27.5 g of water were added and stirred for 30 minutes to produce marine biodegradable polymer compound B-8, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-8 were replaced with potassium ions. It was obtained as a mass% aqueous dispersion.

[0123] [Examples 2-9] Synthesis of marine biodegradable polymer compound B-9 50.0 g of marine biodegradable polymer compound A-9 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 15.9 g of 30% by mass potassium hydroxide aqueous solution and 34.1 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-9 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-9 were replaced with potassium ions.

[0124] [Example 2-10] Synthesis of marine biodegradable polymer compound B-10 50.0 g of marine biodegradable polymer compound A-10 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 10.1 g of 30% by mass potassium hydroxide aqueous solution and 39.9 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound B-10 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound A-10 were replaced with potassium ions. Subsequently, 10.0 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-10 was taken out, heated to evaporate the water, and dried under reduced pressure at 120°C for 2 hours to obtain marine biodegradable polymer compound B-10 as a solid resin. A film with a thickness of 300 μm was produced by press molding the solid resin of marine biodegradable polymer compound B-10 at 120°C.

[0125] [Comparative Example 2-1] Synthesis of Polymer Compound Y-1 50.0 g of marine biodegradable polymer compound X-1 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 19.5 g of 30% by mass potassium hydroxide aqueous solution and 30.5 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound Y-1 as a 50% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound X-1 were replaced with potassium ions. Subsequently, 30.0 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound Y-1 was taken out, heated to evaporate the water, and dried under reduced pressure at 120°C for 2 hours to obtain marine biodegradable polymer compound Y-1 as a solid resin.

[0126] [Comparative Example 2-2] Synthesis of Polymer Compound Y-2 30.0 g of marine biodegradable polymer compound X-2 was added to a 500 mL reaction vessel and melted at 120°C. Subsequently, 81.7 g of 30% by mass potassium hydroxide aqueous solution and 8.25 g of water were added and stirred for 30 minutes to obtain marine biodegradable polymer compound Y-2 as a 25% by mass aqueous dispersion, in which 100% of the protons in the acidic groups of marine biodegradable polymer compound X-2 were replaced with potassium ions. Subsequently, 48.0 g of a 25% by mass aqueous dispersion of marine biodegradable polymer compound Y-2 was taken out, heated to evaporate the water, and dried under reduced pressure at 120°C for 2 hours to obtain marine biodegradable polymer compound Y-2 as a solid resin.

[0127] Table 2 below shows the marine biodegradable polymer compounds B-1 to B-10 and Y-1 to Y-2 together.

[0128] [Table 2]

[0129] [3] Synthesis of marine biodegradable polymer compound C

[0130] [Example 3-1] Synthesis of marine biodegradable polymer compound C-1 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-1 and 42.9 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-1, in which 100% of the acidic groups were bonded via calcium ions.

[0131] [Example 3-2] Synthesis of marine biodegradable polymer compound C-2 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-2 and 37.0 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-2, in which 100% of the acidic groups were bonded via calcium ions.

[0132] [Example 3-3] Synthesis of marine biodegradable polymer compound C-3 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-3 and 22.1 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-3, in which 50% of the acidic groups were bonded via calcium ions.

[0133] [Examples 3-4] Synthesis of marine biodegradable polymer compound C-4 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-4 and 29.6 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-4, in which 100% of the acidic groups were bonded via calcium ions.

[0134] [Examples 3-5] Synthesis of marine biodegradable polymer compound C-5 In a 500 mL reaction vessel, 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-5, 78.0 g of a 25% by mass aqueous solution of aluminum chloride, and 5.56 g of myristoyl sarcosine were added and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-5, in which 70% of the acidic groups were bonded via aluminum ions.

[0135] [Examples 3-6] Synthesis of marine biodegradable polymer compound C-6 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-6 and 58.8 g of a 25% by mass aqueous solution of strontium chloride were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-6, in which 100% of the acidic groups were bonded via strontium ions.

[0136] [Examples 3-7] Synthesis of marine biodegradable polymer compound C-7 70 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-7 and 3.94 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-7, in which 30% of the acidic groups were bonded via calcium ions.

[0137] [Examples 3-8] Synthesis of marine biodegradable polymer compound C-8 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-8 and 55.0 g of a 25% by mass aqueous magnesium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-8, in which 100% of the acidic groups were bonded via magnesium ions.

[0138] [Examples 3-9] Synthesis of marine biodegradable polymer compound C-9 100 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-9 and 45.4 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-9, in which 100% of the acidic groups were bonded via calcium ions.

[0139] [Example 3-10] Synthesis of marine biodegradable polymer compound C-10 90 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound B-10 and 25.9 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound C-10, in which 100% of the acidic groups were bonded via calcium ions. A 300 μm thick film was produced by press-molding the marine biodegradable polymer compound C-10 at 120°C.

[0140] [Comparative Example 3-1] Synthesis of Polymer Compound Z-1 70 g of a 50% by mass aqueous dispersion of marine biodegradable polymer compound Y-1 and 38.8 g of a 25% by mass aqueous calcium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound Z-1, in which 100% of the acidic groups were bonded via calcium ions.

[0141] [Comparative Example 3-2] Synthesis of Polymer Compound Z-2 72.0 g of a 25% by mass aqueous dispersion of marine biodegradable polymer compound Y-2 and 143 g of a 25% by mass aqueous magnesium chloride solution were added to a 500 mL reaction vessel and stirred at 120°C for 30 minutes, resulting in the formation of a precipitate. After washing the precipitate with water, it was dried under reduced pressure to obtain marine biodegradable polymer compound Z-2, in which 100% of the acidic groups were bonded via magnesium ions.

[0142] Table 3 below shows the marine biodegradable polymer compounds C-1 to C-10 and Z-1 to Z-2 together. [Table 3]

[0143] [4] Biodegradability test of marine biodegradable polymer compound A [Examples 4-1 to 4-10, Comparative Examples 4-1 to 4-2] The following seawater biodegradation tests were conducted on marine biodegradable polymer compounds A-1 to A-10 and marine biodegradable polymer compounds X-1 to X-2 using the method described below. Solid samples were pre-ground and sieved to obtain powder particles of 20 μm or less. Microcrystalline cellulose (Avicel PH-101, manufactured by Sigma-Aldrich) was used as a control material, and the relative biodegradation of the cellulose was evaluated. The results are shown in Table 4.

[0144] <Testing methods and conditions> Method for measuring biodegradability: Measurement of oxygen consumption using a closed-loop respirator (refer to ASTM D6691). Test equipment: OxiTop IDS (manufactured by WTW) Culture temperature: 30±1℃, dark place Biodegradation (%)=(BOD O -BOD B ) / ThOD×100 BOD O : Biochemical oxygen demand for testing or confirmation of plant source activity (measured value: mg) BOD B : Average biochemical oxygen demand of a blank test (measured value: mg) ThOD: Required when the test material or control material is completely oxidized. Theoretical oxygen demand (calculated value: mg) Relative biodegradability of cellulose (%) = (Maximum biodegradability of test particles / Maximum biodegradability of cellulose) × 100 Seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) The collected seawater was filtered to remove impurities using a 10 μm filter, and then aerated at room temperature (25°C). In addition, ammonium chloride (0.05 g / L) and potassium dihydrogen phosphate (0.1 g / L) were added as inorganic nutrients.

[0145] [Table 4]

[0146] As shown in Table 4, marine biodegradable polymer compound A exhibited biodegradability, achieving a relative degradation of cellulose of 40% or more by 60 days of culture.

[0147] [5] Biodegradability test of marine biodegradable polymer compound B [Examples 5-1 to 5-10, Comparative Examples 5-1 to 5-2] The following seawater biodegradation tests were conducted on marine biodegradable polymer compounds B-1 to B-10 and marine biodegradable polymer compounds Y-1 to Y-2 using the method described below. Microcrystalline cellulose (Avicel PH-101, manufactured by Sigma-Aldrich) was used as a control material, and the relative biodegradation of the cellulose was evaluated. The results are shown in Table 5.

[0148] <Testing methods and conditions> Method for measuring biodegradability: Measurement of oxygen consumption using a closed-loop respirator (refer to ASTM D6691). Test equipment: OxiTop IDS (manufactured by WTW) Culture temperature: 30±1℃, dark place Biodegradation (%)=(BOD O -BOD B ) / ThOD×100 BOD O : Biochemical oxygen demand for testing or confirmation of plant source activity (measured value: mg) BOD B : Average biochemical oxygen demand of a blank test (measured value: mg) ThOD: Required when the test material or control material is completely oxidized. Theoretical oxygen demand (calculated value: mg) Relative biodegradability of cellulose (%) = (Maximum biodegradability of test particles / Maximum biodegradability of cellulose) × 100 Seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) The collected seawater was filtered to remove impurities using a 10 μm filter, and then aerated at room temperature (25°C). In addition, ammonium chloride (0.05 g / L) and potassium dihydrogen phosphate (0.1 g / L) were added as inorganic nutrients.

[0149] [Table 5]

[0150] As shown in Table 5, marine biodegradable polymer compound B showed biodegradability, with a relative degradation of cellulose of 40% or more by 60 days of culture.

[0151] [6] Biodegradability test of marine biodegradable polymer compound C [Examples 6-1 to 6-10, Comparative Examples 6-1 to 6-2] The following seawater biodegradation tests were conducted on marine biodegradable polymer compounds C-1 to C-10 and Z-1 to Z-2 using the method described below. Microcrystalline cellulose (Avicel PH-101, manufactured by Sigma-Aldrich) was used as a control material, and the relative biodegradation rate of the cellulose was evaluated. The results are shown in Table 6.

[0152] <Testing methods and conditions> Method for measuring biodegradability: Measurement of oxygen consumption using a closed-loop respirator (refer to ASTM D6691). Test equipment: OxiTop IDS (manufactured by WTW) Culture temperature: 30±1℃, dark place Biodegradation (%)=(BOD O -BOD B ) / ThOD×100 BOD O : Biochemical oxygen demand for testing or confirmation of plant source activity (measured value: mg) BOD B : Average biochemical oxygen demand of a blank test (measured value: mg) ThOD: Required when the test material or control material is completely oxidized. Theoretical oxygen demand (calculated value: mg) Relative biodegradability of cellulose (%) = (Maximum biodegradability of test particles / Maximum biodegradability of cellulose) × 100 Seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) The collected seawater was filtered to remove impurities using a 10 μm filter, and then aerated at room temperature (25°C). In addition, ammonium chloride (0.05 g / L) and potassium dihydrogen phosphate (0.1 g / L) were added as inorganic nutrients.

[0153] [Table 6]

[0154] As shown in Table 6, marine biodegradable polymer compound C exhibited biodegradability, achieving a relative degradation of 40% or more of cellulose by 60 days of culture.

[0155] [7] Preparation of marine biodegradable compositions and confirmation tests in seawater - 1 (1) Surface changes [Examples 7-1 to 7-12, Comparative Examples 7-1 to 7-3] PBSA (FD-92, manufactured by Mitsubishi Chemical Corporation) was pulverized using a pulverizer (Wonder Blender WB-1, manufactured by Osaka Chemical Co., Ltd.), and marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 were classified using a stainless steel sieve (mesh size 26 μm). These compounds were melt-kneaded at 140°C to a concentration of 20% by mass, and then press-molded at 150°C to produce films with a thickness of 200 μm (Examples 7-1 to 7-12, Comparative Examples 7-1 to 7-2). In addition, PBSA itself (without marine biodegradable polymer compounds) was press-molded at 150°C to produce a film with a thickness of 200 μm (Comparative Example 7-3). Furthermore, the obtained films were processed into 10 mm squares and placed in 200 mL of deionized water and 200 mL of seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]), respectively. After standing at 25°C for 7 and 30 days, the films were removed and their surfaces and appearance were observed using a scanning electron microscope. The results are shown in Table 7.

[0156] [Table 7]

[0157] Based on the results shown in Table 7, it is considered that biodegradation is accelerated by the presence of microorganisms in the seawater, in addition to the breakdown caused by seawater.

[0158] (2) Weight reduction of composite resin [Examples 8-1 to 8-12, Comparative Examples 8-1 to 8-3] Using the same method as in (1), films were prepared by adding marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 to PBSA, as well as a film of PBSA alone. The obtained films were processed into 20 mm squares, sandwiched between stainless steel nets, and immersed in seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) in a 15 L tank. The weight loss after immersion was observed after 30, 60, and 90 days. The results are shown in Table 8.

[0159] [Table 8]

[0160] Based on the results shown in Table 8, it is considered that biodegradation is accelerated by the presence of microorganisms in the seawater, in addition to the breakdown caused by seawater.

[0161] (3) Measurement of tensile strength [Examples 9-1 to 9-12, Comparative Examples 9-1 to 9-2] Using the same method as in (1), films were prepared by adding marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 to PBSA at concentrations of 10% by mass, 20% by mass, or 30% by mass, respectively, as well as a film of PBSA alone. Dumbbells were prepared from each film according to JIS K 7139-A22, and the tensile stress (yield point) was measured using a universal testing machine (AGS-X, manufactured by Shimadzu Corporation). Each sample was measured five times, and the average value was taken as the tensile stress. The results are shown in Table 9.

[0162] [Table 9]

[0163] The results shown in Table 9 confirm that the marine biodegradable polymer compound of the present invention exhibits improved mechanical properties compared to Z-1.

[0164] (4) Softening point measurement [Examples 10-1 to 10-12, Comparative Examples 10-1 to 10-2] Using the same method as in (1), films were prepared by adding marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 to PBSA at concentrations of 10% by mass, 20% by mass, or 30% by mass, respectively, as well as a film of PBSA alone. The softening points were measured using a thermomechanical analyzer (TMA4000SE, manufactured by NETZSCH Japan Co., Ltd.). Specifically, a 1.5 mm thick, 3 mm square test piece was subjected to a 0.5 g load, and the softening point was defined as the temperature at which a 150 μm penetration was observed within a temperature range of 25 to 200 °C (heating rate of 3 °C / min). The results are shown in Table 10.

[0165] [Table 10]

[0166] The results shown in Table 10 confirm that the marine biodegradable polymer compound of the present invention exhibits improved thermophysical properties compared to Z-1.

[0167] [8] Preparation of marine biodegradable compositions and confirmation tests in seawater - 2 (1) Surface changes [Examples 11-1 to 11-12, Comparative Examples 11-1 to 11-3] A biodegradable starch-based resin (Mater-Bi EF05B, manufactured by Novamont) was pulverized using a pulverizer (Wonder Blender WB-1, manufactured by Osaka Chemical Co., Ltd.), and marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 were classified using a stainless steel sieve (mesh opening 26 μm). These compounds were melt-kneaded at 140°C to a concentration of 20% by mass, and then press-molded at 150°C to produce films with a thickness of 200 μm (Examples 11-1 to 11 to 12, Comparative Examples 11-1 to 11-2). In addition, the starch-based resin itself (without particle groups) was press-molded at 150°C to produce a film with a thickness of 200 μm (Comparative Example 11-3). Furthermore, the obtained films were processed into 10 mm squares and placed in 200 mL of deionized water and 200 mL of seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]), respectively. After standing at 25°C for 7 and 30 days, the films were removed and their surfaces and appearance were observed using a scanning electron microscope. The results are shown in Table 11.

[0168] [Table 11]

[0169] Based on the results shown in Table 11, it is considered that biodegradation is accelerated by the presence of microorganisms in the seawater, in addition to the breakdown caused by seawater.

[0170] (2) Weight reduction of composite resin [Examples 12-1 to 12 to 12, Comparative Examples 12-1 to 12-3] Using the same method as in (1), films were prepared by adding marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 to starch resin, as well as films of starch resin alone. The obtained films were processed into 20 mm squares, sandwiched between stainless steel nets, and immersed in seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) in a 15 L tank. The weight loss after immersion was observed after 30, 60, and 90 days. The results are shown in Table 12.

[0171] [Table 12]

[0172] Based on the results shown in Table 12, it is considered that biodegradation is accelerated by the presence of microorganisms in the seawater, in addition to the breakdown caused by seawater.

[0173] (3) Measurement of tensile strength [Examples 13-1 to 13-12, Comparative Examples 13-1 to 13-2] Using the same method as in (1), films were prepared in which marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 were added to a starch-based resin at concentrations of 10% by mass, 20% by mass, or 30% by mass, respectively, as well as films of the starch-based resin alone. Dumbbells were prepared from various films in accordance with JIS K 7139-A22, and the tensile stress (yield point) was measured using a universal testing machine (AGS-X, manufactured by Shimadzu Corporation). Each sample was measured five times, and the average value was taken as the tensile stress. The results are shown in Table 13.

[0174] [Table 13]

[0175] The results shown in Table 13 confirm that the marine biodegradable polymer compound of the present invention exhibits improved mechanical properties compared to Z-1.

[0176] (4) Softening point measurement [Examples 14-1 to 14-12, Comparative Examples 14-1 to 14-2] Using the same method as in (1), films were prepared by adding marine biodegradable polymer compounds C-1 to C-10, A-3, B-7, and Z-1 to Z-2 to a starch-based resin at concentrations of 10% by mass, 20% by mass, or 30% by mass, respectively, as well as films of the starch-based resin alone. The softening points were measured using a thermomechanical analyzer (TMA4000SE, manufactured by NETZSCH Japan Co., Ltd.). Specifically, a 1.5 mm thick, 3 mm square test piece was subjected to a 0.5 g load, and the softening point was defined as the temperature at which a 150 μm penetration was observed within the temperature range of 25 to 200 °C (heating rate of 3 °C / min). The results are shown in Table 14.

[0177] [Table 14]

[0178] The results shown in Table 14 confirm that the marine biodegradable polymer compound of the present invention exhibits improved thermophysical properties compared to Z-1.

[0179] Based on the above results, the marine biodegradable polymer compound of the present invention dissolves or becomes more hydrophilic in seawater by being reduced in molecular weight or undergoing salt substitution through biodegradation prior to that of biodegradable resins. Therefore, by adding a marine biodegradation accelerator containing the marine biodegradable polymer compound of the present invention to resin compositions that are biodegradable in soil or compost, or resin compositions that have low biodegradability in the ocean, it becomes possible to create an uneven surface in seawater, facilitate the attachment of microorganisms, and promote biodegradation. As a result, it becomes possible to improve the overall marine biodegradability and reduce the environmental burden. By combining the marine biodegradable polymer compound of the present invention with a marine biodegradation accelerator that is biodegradable in soil or compost, seawater biodegradability can be improved. Furthermore, by appropriately changing the structure of the organic anion, multiple effects can be incorporated, such as adjusting the melting temperature and viscosity, adjusting the degree of crystallinity, adjusting microbial adhesion and biodegradability, adjusting physical properties such as resin tensile strength, flexural strength, and elasticity, improving compatibility with the resin, adjusting the degree of hydrophobicity, adjusting hydrophobicity, and adjusting adhesion and plasticity. Thus, improvements can be made to both the biodegradability and physical properties of the marine biodegradable composition.

Claims

1. A marine biodegradable polymer compound comprising a polymer-type polyvalent anion containing a structural unit consisting of an oligomer and a linking group containing two or more monovalent anionic substituents, and a monovalent cation.

2. The marine biodegradable polymer compound according to claim 1, wherein the monovalent cation is a proton, a monovalent metal cation, or a monovalent organic cation.

3. The marine biodegradable polymer compound according to claim 1, wherein the oligomer contains repeating units linked by ester bonds, amide bonds, or ether bonds.

4. The marine biodegradable polymer compound according to claim 1, wherein the number-average molecular weight of the oligomer is 400 to 10,000.

5. The marine biodegradable polymer compound according to claim 1, wherein the number of structural units consisting of the oligomer and the linking group is 2 to 50.

6. The marine biodegradable polymer compound according to claim 1, wherein the content of the oligomer component is 30 to 99% by mass, and the content of the linking group component is 1 to 70% by mass.

7. The marine biodegradable polymer compound according to claim 1, wherein the terminal end is a carboxyl group, a hydroxyl group, or an amino group.

8. The marine biodegradable polymer compound according to claim 1, wherein the number average molecular weight is 800 to 200,000.

9. The marine biodegradable polymer compound according to claim 1, wherein the monovalent anionic substituent is bonded to the linking group via 1 to 30 atoms.

10. The marine biodegradable polymer compound according to claim 1, wherein the proportion of non-proton groups among the monovalent cations is 1 to 100%.

11. A marine biodegradable polymer compound comprising a polymer-type polyvalent anion linked via a divalent or greater cation, containing a structural unit consisting of an oligomer and a linking group containing two or more monovalent anionic substituents.

12. The content of the aforementioned divalent or greater cation is 1 to 100 eq / 10 5 The marine biodegradable polymer compound according to claim 11, wherein the compound is g.

13. A marine biodegradable composition comprising a marine biodegradable polymer compound according to any one of claims 1 to 12.

14. A marine biodegradation accelerator comprising the marine biodegradable composition according to claim 13.

15. A molded article obtained from the marine biodegradable composition according to claim 13.

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